Dynamic Thermal Simulation & Systems Sizing Report · 5 Executive Summary This report has been...

Dynamic Thermal Simulation & Systems Sizing

Report

Hillside Cottage Sevenmarks Hampshire

Project Number: GRL14-007

Revision: Draft/For Comment

Date: 06.02.2015

© Richard Tibenham Consulting 2015. All rights reserved.

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This report has been produced by: Richard Tibenham (Director) Greenlite Energy Assessors 11 Yarborough Terrace, Lincoln. LN1 1HN T: 01522 581234 E: [email protected] For: Ian de-Peyrecave Perry+Bell Ltd 21 Woodstock Street London W1C 2AP

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Contents:

Executive SummaryExecutive SummaryExecutive SummaryExecutive Summary

1.01.01.01.0 IntroductionIntroductionIntroductionIntroduction 6666

2.02.02.02.0 Simulated ParametersSimulated ParametersSimulated ParametersSimulated Parameters 7777 2.12.12.12.1 Location/weather fileLocation/weather fileLocation/weather fileLocation/weather file 7777

2.22.22.22.2 GeometryGeometryGeometryGeometry 8888

2.32.32.32.3 Construction FabricConstruction FabricConstruction FabricConstruction Fabric 9999

2.42.42.42.4 Construction DetailingConstruction DetailingConstruction DetailingConstruction Detailing 14141414

2.52.52.52.5 Air tightnessAir tightnessAir tightnessAir tightness 14141414

2.62.62.62.6 HVAC Systems; OverviewHVAC Systems; OverviewHVAC Systems; OverviewHVAC Systems; Overview 15151515

2.72.72.72.7 MVHR Unit & Earth Tube ModellingMVHR Unit & Earth Tube ModellingMVHR Unit & Earth Tube ModellingMVHR Unit & Earth Tube Modelling 17171717

2.82.82.82.8 DHW Heating System DHW Heating System DHW Heating System DHW Heating System 25252525

2.92.92.92.9 Internal Gains; Occupants, Internal Gains; Occupants, Internal Gains; Occupants, Internal Gains; Occupants, Lighting & EquipmentLighting & EquipmentLighting & EquipmentLighting & Equipment 34343434

2.102.102.102.10 Humidity Gains and CO2 levelsHumidity Gains and CO2 levelsHumidity Gains and CO2 levelsHumidity Gains and CO2 levels 41414141

2.112.112.112.11 Control of Windows and DoorsControl of Windows and DoorsControl of Windows and DoorsControl of Windows and Doors 42424242

3.03.03.03.0 Simulation ResultsSimulation ResultsSimulation ResultsSimulation Results 43434343 3.13.13.13.1 Study into Local Space Heating DemandStudy into Local Space Heating DemandStudy into Local Space Heating DemandStudy into Local Space Heating Demand 54545454

3.23.23.23.2 Study into Internal TemperaturesStudy into Internal TemperaturesStudy into Internal TemperaturesStudy into Internal Temperatures 55555555

3.33.33.33.3 StudStudStudStudy into performance of Earth Tube and MVHR unity into performance of Earth Tube and MVHR unity into performance of Earth Tube and MVHR unity into performance of Earth Tube and MVHR unit 57575757

4.04.04.04.0 SSSStudy oftudy oftudy oftudy of Suitable Sizing of Suitable Sizing of Suitable Sizing of Suitable Sizing of the the the the Thermal StoreThermal StoreThermal StoreThermal Store 62626262 4.14.14.14.1 Investigation into the relationship of Thermal Store Capacity and Investigation into the relationship of Thermal Store Capacity and Investigation into the relationship of Thermal Store Capacity and Investigation into the relationship of Thermal Store Capacity and 63636363

Auxiliary Energy Inputs based on Solar Thermal Inputs AloneAuxiliary Energy Inputs based on Solar Thermal Inputs AloneAuxiliary Energy Inputs based on Solar Thermal Inputs AloneAuxiliary Energy Inputs based on Solar Thermal Inputs Alone

4.24.24.24.2 Investigation into the Effect of Additional Insulation to the Thermal StoreInvestigation into the Effect of Additional Insulation to the Thermal StoreInvestigation into the Effect of Additional Insulation to the Thermal StoreInvestigation into the Effect of Additional Insulation to the Thermal Store 67676767

4.34.34.34.3 Investigation into the Inclusion of Photovoltaic Array Inputs via Immersion Investigation into the Inclusion of Photovoltaic Array Inputs via Immersion Investigation into the Inclusion of Photovoltaic Array Inputs via Immersion Investigation into the Inclusion of Photovoltaic Array Inputs via Immersion 71717171

HeatersHeatersHeatersHeaters

4.44.44.44.4 Investigation into the Effect of a Dual Store SystemInvestigation into the Effect of a Dual Store SystemInvestigation into the Effect of a Dual Store SystemInvestigation into the Effect of a Dual Store System 77777777 5.05.05.05.0 Conclusions & rConclusions & rConclusions & rConclusions & recommendationsecommendationsecommendationsecommendations 79797979 5.15.15.15.1 ConclusionsConclusionsConclusionsConclusions 79797979

5555.2.2.2.2 RecommendationsRecommendationsRecommendationsRecommendations 80808080

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Schedule of Revisions:Schedule of Revisions:Schedule of Revisions:Schedule of Revisions:

Revision:Revision:Revision:Revision: DateDateDateDate Notes:Notes:Notes:Notes: Assembled by:Assembled by:Assembled by:Assembled by:

Draft/for Comment

06.02.15 Based on documentation provided by client. Suitable assumptions made where information is not yet available and described within report.

RT

Prepared by: Richard Tibenham ....................................................

Director

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Executive Summary This report has been commissioned by Ian de-Peyrecave to aid in the design of Hillside Cottage, Four Marks, Hampshire. The building is designed around the philosophy of very low energy demand, of which, a substantial proportion is to be generated using on site active solar thermal systems. This philosophy shall be achieved through the reduction of energy demand using Passivhaus design and construction principles; namely very high levels of thermal insulation, thermal bridge free junction detailing, very high levels of air tightness, predominantly south orientated glazing and a mechanical ventilation system with heat recovery and an earth tube frost protection supply routing. Heating to the dwelling shall be achieved through the use of a low temperature hot water radiator circuit, utilising over-sized low temperature radiators operating at 45°C. An array of evacuated tube solar thermal collectors shall be located on the roof of the building, to provide for domestic hot water generation, and supplement to some degree energy generation for space heating. The principle purpose of this report is to investigate appropriate sizing of this active solar thermal system in the context of the building’s space heating and domestic hot water loads. A detailed dynamic thermal simulation has been conducted using IES Virtual Environment software, in order to establish the buildings space heating demand and in order to investigate further a range of aspects of the design, including space heating system design & sizing and overheating analysis. Further detailed modelling of the solar thermal system has been conducted using Valentin T*Sol simulation software, owing to the approximations for solar thermal systems modelling applied within the IES software. It is concluded that where a 1500ltr thermal store is included, approximately 50% of the building’s domestic hot water and space heating demands shall be met through local renewable solar systems. In addition, energy equal to approximately 25% of the domestic hot water and space heating demand is likely to be available for export to the electrical grid during the summer, resulting in a net energy provision from renewable technologies of around 75% of the annual space heating and domestic hot water energy demand.

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1.0 Introduction Hillside Cottage, located within the village of Four Marks, Hampshire is the proposed dwelling for owner/builder, architect and client, Ian de-Peyrecave. The dwelling is built into a hillside over three floors and includes four bedrooms, two reception rooms, four en-suite bathrooms and two kitchens (main kitchen and utility). The building is located with the longitudinal axis of the building running directly east-west, with the front elevation of the building orientated due south. The roof, at a 30° pitch, features a vertical element at the top for the locating of winter sun optimised solar thermal collectors. The design intent of the building is to operate with a very low energy demand, and to provide for much of this demand through onsite renewable energy generation. It is designed with the intent of potential future off-grid operation. The building is built using Passivhaus design principles, featuring very high efficiency thermal insulation, very high levels of air tightness, thermal bridge free detailing, triple glazing, a mechanical ventilation system with earth tube and predominantly south facing glazing. It is intended that the building shall provide for as much of the energy demand as is feasibly possible through onsite solar technologies. Solar thermal collectors shall be located on the vertical element of the roof in order to optimise winter time gains. A solar PV array shall be present on the 30° pitched roof for supplementing hot water and space heating generation all year round, but shall produce the highest yield during the summer months. Both systems shall supply heat to one or more thermal stores, from which a low temperature hot water (LTHW ) circuit shall run, feeding over-sized low temperature (45°C) radiators. Domestic hot water (DHW) shall also run from the same thermal store(s). This report investigates the design of the building through the investigation of the heating demand likely from such a specification and a detailed study of the available solar energy at the site. Conclusions are drawn concerning the specification of plant required to yield as much solar energy as is feasibly possible. A full description of this process is laid out across the following sections of the report.

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2.0 Simulated Parameters

2.12.12.12.1 Location/weather file;Location/weather file;Location/weather file;Location/weather file;

The proposed site of the building is located at Four Marks, Hampshire, approximately fourteen miles east of Winchester and twenty-four miles north east of Southampton.

As such, the CIBSE Southampton TRY05 weather file has been selected for this simulation. The TRY (Typical Reference Year) file adopts typical weather data for this location.

A minimum temperature of -5.7°C is utilised within the heating simulation.

For overheating risk analysis, the CIBSE Southampton DSY05 weather file has been selected, accounting for ‘Design Summer Year’ weather data, which accounts for higher summer time temperatures.

Fig 1. Location mapFig 1. Location mapFig 1. Location mapFig 1. Location map

Obscured for client

confidentiality

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2.22.22.22.2 GeometryGeometryGeometryGeometry

The building has been modelled using the IES native modelling program ‘ModelIT’ and accounts for all shading surfaces to the building and local shading objects which will have an effect on solar gains to the building.

Note that trees directly to the south of the property are accounted to be removed.

Modelling of the building fabric is based upon architectural drawings provided by the client, with the addition of a speculative airing cupboard in the space beneath the lower ground floor stairs.

The building is modelled as indicated on architectural drawings, with the front elevation of the building orientated due south.

Construction Geometry used within the simulations is shown below:

Fig 2. Aerial ViewFig 2. Aerial ViewFig 2. Aerial ViewFig 2. Aerial View

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Fig 3. South ElevationFig 3. South ElevationFig 3. South ElevationFig 3. South Elevation Fig 4. North ElevationFig 4. North ElevationFig 4. North ElevationFig 4. North Elevation

Fig 5. West ElevationFig 5. West ElevationFig 5. West ElevationFig 5. West Elevation Fig 6Fig 6Fig 6Fig 6. East Elevation. East Elevation. East Elevation. East Elevation

Fig 7Fig 7Fig 7Fig 7. South . South . South . South East Aerial ViewEast Aerial ViewEast Aerial ViewEast Aerial View Fig 8Fig 8Fig 8Fig 8. South West Aerial View. South West Aerial View. South West Aerial View. South West Aerial View

Fig 9. North West Aerial View Fig 10. North East Aerial

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Geometric Modelling Notes;Geometric Modelling Notes;Geometric Modelling Notes;Geometric Modelling Notes;

The architectural information submitted does not confirm the build-up of certain areas of the construction. All roofs are accounted to be warm roof constructions, including those above the Utility Kitchen and Study/Office.

Warm Roof Warm Roof

Fig 11Fig 11Fig 11Fig 11. Utility Kitchen Roof. Utility Kitchen Roof. Utility Kitchen Roof. Utility Kitchen Roof Fig 12Fig 12Fig 12Fig 12. Study Roof. Study Roof. Study Roof. Study Roof

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2.32.32.32.3 Construction FabricConstruction FabricConstruction FabricConstruction Fabric

Construction fabric used within the calculation is based upon architectural information provided by the client and amended where necessary to create a thermal envelope achieving a U-Value of 0.1 W/m².k¯¹ to the floor, roof and walls.

Glazing information is based upon architectural window schedules and information provided by the proposed glazing manufacturer, Gaulhofer (via EcoWin).

When detailed construction build-ups have been confirmed, accurate U-Value calculations can be made and used to update the simulation if necessary.

The following construction fabric has been used within this assessment. Note the descriptions provide only an approximate description of the actual build-up; necessary in order to account for thermal bridging and incontinuities in the fabric. The design U-values and thermal mass figures are of principle importance;

2.3.1 Opaque Construction Fabric2.3.1 Opaque Construction Fabric2.3.1 Opaque Construction Fabric2.3.1 Opaque Construction Fabric

Element Description Composition U-Value (W/m².K)

Thermal Mass KJ/(m².K)

External Walls

External walls (Lower GF) -100mm Outer Brick leaf -306mm Drittherm 32 Mineral wool or similar -25mm Gpypsum Plasterboard

0.100.100.100.10 19.95

External walls (Upper GF + FF) -10mm Timberboard -308mm Drittherm 32 Minerla wool or similar -25mm Gpypsum Plasterboard

0.100.100.100.10 19.95

Retaining Wall -220mm Concrete -304mm Dritherm 32 Mineral wool or similar -25mm Gypsum Plasterboard

0.100.100.100.10 19.95

Floors

Lower Ground Floor Construction

- 160mm PUR Rigid foam Insulation - 100mm Cast Concrete -50mm Screed

0.100.100.100.10 138.60

Ground Floor Construction -170mm PUR Rigid Foam Insulation -100mm Cast Concrete -50mm Screed

0.100.100.100.10 138.60

Roof

Warm Roof Construction - Tiles and felt -313mm Dritherm 32 Mineral Wool or similar -12.5mm Gypsum Plasterboard

0.100.100.100.10 9.98

Fig Fig Fig Fig 13131313. Table of Opaque Construction Elements. Table of Opaque Construction Elements. Table of Opaque Construction Elements. Table of Opaque Construction Elements

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Internal Partitions

Lightweight Partition - 3mm plaster skim -25mm Gypsum Plasterboard -70mm Void -25mm Gypsum Plasterboard - 3mm plaster skim

1.27 21.75

Insulated Plant Room Partition (Advised)*

-12.5mm Gypsum plaster board -200mm Dritherm 32 or similar -100mm Brickwork

0.14 136.00

Internal Floors

Plasterboard Ceilings -3mm Plaster skim -12.5mm Gypsum Plasteboard

3.16 6.79

Timber Intermediate Floor -10mm Synthetic Carpet -18mm Chipbaord

2.05 23.44

Doors

External doors -12mm Oak Veneer -28mm PUR foam -12mm Oak Veneer

0.63 (estimate)

20.07

Internal doors -8mm Oak veneer -30mm Chipboard -8mm Oak veneer

2.20 38.5

*It is recommended to install an insulated partition between occupied areas and the plant room in order to avoid summer time heat gains which may result from high temperatures within thermal stores.

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2.3.22.3.22.3.22.3.2 Glazing:Glazing:Glazing:Glazing:

Glazing parameters have been input based on architectural window schedule drawings and information provided by EcoWin. Certain aspects of the parameters input into the simulation have been estimated due to information not being available. In order to fully account for the windows as specified, the following information should also be provided;

• Total external dimensions

• Glazed area only

• Frame material U-values The following information has been input into the assessment;

Glazing U-Value (W/m².K) Frame Factor

g-value

LT-value

Glazing Frame Total

A1 (A) 0.50 1.23 0.86 50% 0.51 0.72

A2 (B) 0.50 1.22 0.81 43% 0.51 0.72

A3 (C) 0.50 1.18 0.79 43% 0.51 0.72

A4 (D) 0.50 1.24 0.79 39% 0.51 0.72

A5 (E) 0.50 1.25 0.79 39% 0.51 0.72

A6 (F) 0.50 1.18 0.77 40% 0.51 0.72

A7 (G) 0.50 1.17 0.74 36% 0.51 0.72

A8 (H) 0.50 0.97 0.72 47% 0.51 0.72

A9 (I) 0.50 0.97 0.72 47% 0.51 0.72

A10 (J) 0.50 1.05 0.76 47% 0.51 0.72

A11 (K) 0.50 1.04 0.71 39% 0.51 0.72

A12 (L) 0.50 0.94 0.68 44% 0.52 0.60

A13 (M) 0.50 1.09 0.76 44% 0.51 0.72

A14 (N) 0.50 1.13 0.75 40% 0.51 0.72

A15 (O) 0.50 1.23 0.79 40% 0.51 0.72

A16 (P) 0.50 1.13 0.75 40% 0.51 0.72

Fig 14Fig 14Fig 14Fig 14. Table of Glazing Elements. Table of Glazing Elements. Table of Glazing Elements. Table of Glazing Elements

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2.42.42.42.4 Construction DetailingConstruction DetailingConstruction DetailingConstruction Detailing

Fabric junctions are not accounted for within the IES software. As such, any additional heat leakage via fabric junctions should be accounted for as an addition to the fabric U-Values in which the junctions are present.

The simulation described within this report accounts for tttthermal bridghermal bridghermal bridghermal bridge free detailing e free detailing e free detailing e free detailing to all construction junctions, as would be necessary for Passivhaus design.

When construction junctions are fully defined, should these not achieve thermal bridge free detailing, these can be assessed in order to establish a Psi-Value for the junction (W/m) and subsequently incorporated into the IES simulation.

2.52.52.52.5 Ait TightnessAit TightnessAit TightnessAit Tightness

Air permeability has been modelled into all areas at a rate of 0.01ACH. This equates to the Passivhaus standard of air tightness of 0.6ACH@50Pa +/-, corrected for normal operating pressures. A reduction factor of 1/60 has been applied in accordance with the guidance of CIBSE TM23 ‘Testing Buildings for Air Leakage’.

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2.62.62.62.6 HVAC Systems; OverviewHVAC Systems; OverviewHVAC Systems; OverviewHVAC Systems; Overview

HVAC systems have been modelled into the simulation using the IES Apache HVAC System Simulation Interface, which allows much greater control of HVAC systems than modelling within the IES Apache Simulation alone. The system accounts for a thermal store, heated using solar thermal collector inputs and supplementary heat inputs from a gas fired boiler. The thermal store is used for the provision of space heating, via LTHW over-sized radiators, operating at a 45°C flow temperature. DHW services are also drawn from the same single thermal store. Mechanical ventilation is assigned based upon the PAUL Novus MVHR unit, though this is purely indicative – units providing similar levels of heat recovery may be used without detriment to the simulated thermal outcomes. The supply routing to the MVHR unit accounts for an earth tube sub-surface frost protection pipe –raising the flow temperature during the winter and reducing it during the summer. The ventilation system is assigned with controls to modulate the flow rate dependent upon temperature, moisture and CO2 concentrations –allowing automated control of the flow rate to maintain suitable internal conditions, with no need to disable the unit when windows are opened. A summer-time by-pass damper is modelled within the unit. Solar collectors are modelled upon the roof of the building – initially at the vertical inclination described on the clients drawings, however the performance at pitched orientations are also investigated.

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2.62.62.62.6.1 Space Heating Parameters.1 Space Heating Parameters.1 Space Heating Parameters.1 Space Heating Parameters After investigation of the thermal behaviour of the building, wet radiators are accounted for in the following rooms;

• -01 Reception • -01 Bedroom 4 • -01 Bedroom 3 • -01 Airing Cupboard (beneath stair, speculative) • 00 Main Reception • 00 Study Office • 00 Utility Kitchen • 00 Guest Room • 00 Lobby • 00 Master Bedroom

These are rooms which have either mechanical supply, or are on an air transition path, thus allowing warm air created via the radiators to be drawn to locations with mechanical extract. Where radiators are located within rooms with mechanical extract, this warm air is removed directly. A proportion of heat will be recovered via the heat recovery unit, however where local heating via radiators is not including within a room, space heating is purely via the ventilation system, for which the flow rate may be reduced due to low CO2 or moisture levels. Heating via air only is therefore considered less controllable than that of heating using radiators. Radiators are assigned to become active dependent upon two thermostats, located within;

• 00 Lobby (adj. Utility Kitchen) • -01 Circulation/Stair

When either of these thermostats registers a temperature

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2.72.72.72.7 MVHR Unit & Earth Tube ModellingMVHR Unit & Earth Tube ModellingMVHR Unit & Earth Tube ModellingMVHR Unit & Earth Tube Modelling Mechanical ventilation parameters are based around the PAUL Novus 300 MVHR unit, though this only provides an indication of the possible performance of an MVHR unit and is not prescriptive. Supply and extract locations are based on those shown within the clients drawings. Supply and extract rates have been assigned based on the minimum flow rates as recommended for Passivhaus design (30m³/hr/person = 8.33l/s/person), though these are assign to regulate dependent upon the system sensor inputs detailed below. The following flow rates have been assigned;

Supply Extract

Supply Zones

Min. Rate (l/s)

Design Rate (l/s)

Rate Max. (l/s) Extract Zones

Min. Rate (l/s)

Design Rate (l/s)

Rate Max. (l/s)

Reception 2.78 8.38 10.41 Airing Cup'd 4.31 13.04 16.02 Bedroom 4 2.78 8.38 10.41 Bedroom 4 En-suite 2 6 7.47 Bedroom 3 2.78 8.38 10.41 Bedroom 3 En-suite 2 6 7.47

Main Reception 2.78 8.38 10.41 00 Kitchen 3.31 10 12.46 Dining 2.78 8.38 10.41 00 Guest En-suite 2 6 7.47

Study/Office 2.78 8.38 10.41 00 Utility Kitchen 3.31 10 12.46 Guest Bedroom 2.78 8.38 10.41 01 Master En-suite 2 6 7.47

Master Bedroom 2.78 8.38 10.41 01 Void Above Entrance Hall 3.31 10 12.46

TOTAL 22.24 67.04 83.28 22.24 67.04 83.28

The system accounts for controls via;

• Internal Temperature • Relative Humidity • CO2 sensors

Assigning such controls allows the system to automatically modulate the flow rate dependent upon internal environmental conditions, with little need for user interaction. During the transition months, where windows are opened, the system will automatically reduce the flow rate, or turn off completely, if there is no need for mechanical ventilation.

Fig 15Fig 15Fig 15Fig 15. Table Mechanical Supply and Extract Rates. Table Mechanical Supply and Extract Rates. Table Mechanical Supply and Extract Rates. Table Mechanical Supply and Extract Rates

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2.7.1 Internal temperature sensors -for space heating; The MVHR unit is assigned to regulate the air flow rate dependent upon internal temperature, in order to provide maximum heating via the ventilation system when required and no flow when not required. The flow rate is regulated via a thermostat located within the Lobby adjacent the Utility Kitchen. The signal is ‘ON’ until the thermostat within the Lobby registers >18°C. The control provides a signal to provide full ventilation at 18°C, as shown below:

2.7.2 Internal temperature sensors -for space cooling; A separate thermostatic control has also been located within the Main Reception to register high internal temperatures. The signal is assigned to be ‘ON’ when the internal temperature within the Main Reception is >22°C. The flow rate is assigned to be zero where the internal temperature is 26°C, allowing cooling via ventilation when necessary.

Fig 16Fig 16Fig 16Fig 16. Space Heating Thermostat Settings. Space Heating Thermostat Settings. Space Heating Thermostat Settings. Space Heating Thermostat Settings

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2.72.72.72.7.3 .3 .3 .3 Humidity sensors;Humidity sensors;Humidity sensors;Humidity sensors; Humidity sensors are assigned within all en-suite bathrooms and the airing cupboard. Controls may wish to be extended also to Kitchen areas, or these may want to use a manual control. Such a measure allows the ventilation system to react automatically to changes in humidity levels through showering etc, without the need to manually increase the ventilation rate. The humidity controls increase the flow rate where the relative humidity within these zones increases. The signal is assigned to turn ‘ON’ when the relative humidity within any zone is >45%. The flow rate is assigned to be zero where the relative humidity is 65%, as follows:

Fig 17Fig 17Fig 17Fig 17. Humidity Sensor Settings. Humidity Sensor Settings. Humidity Sensor Settings. Humidity Sensor Settings

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2.7.4 CO2 Sensors A single CO2 sensor is allocated with the Entrance Hall area. This sensor regulates the flow rate dependent upon CO2 levels in the building. Such controls allow the MVHR unit to regulate the flow rate automatically dependent upon CO2 levels – eg where there is a high occupancy rate at a party for example, the ventilation rate will increase to prevent the room from feeling stuffy. The signal is ‘ON’ where CO2 levels exceed 1000ppm. The sensor regulates the flow rate from zero where CO2 levels are 1500ppm, as follows:

Fig 18Fig 18Fig 18Fig 18. CO2 Sensor Settings. CO2 Sensor Settings. CO2 Sensor Settings. CO2 Sensor Settings

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2.7.5 Duct Mounted Heater Battery Control; A duct mounted heater battery is accounted for within the simulation. The heater battery is assigned to be regulated using a duct thermostat located within extract duct, at the point of entering the MVHR unit. The thermostat signal is ‘ON’ when the internal temperature is

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2.7.7 Earth Tube Frost Protection Duct An earth tube has been accounted for within the simulation to model the frost protection aspects of the earth tube and the ability to condition air temperatures closer to room set-point temperatures through the year. The duct is modelled as a series of 200mm dia. 1m long sub-surface modular pipes, as shown below;

An adjacent temperature condition has been assigned to the surface of the pipe using a temperature profile based on estimated soil temperatures at a 1m depth at the site, as shown below;

0

2

4

6

8

10

12

14

16

18

1 3 5 7 9 11 13 15 17 19 21 23 25 27 29 31 33 35 37 39 41 43 45 47 49 51

Te

mp

. (o

C)

Week

Soil Temperature at 1m Depth

Soil

Temperature

at 1m Depth

Fig 20Fig 20Fig 20Fig 20. Air tube External Adjacency Temperature . Air tube External Adjacency Temperature . Air tube External Adjacency Temperature . Air tube External Adjacency Temperature ProfileProfileProfileProfile

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Within the Apache HVAC systems simulation interface, these ten sections of pipe are modelled as ten separate ‘rooms’ through which the air supply to the MVHR unit must flow. As the air moves through the pipe at the flow rate required by the MVHR system, heat is extracted from the soil and into the supply air, raising or reducing the air supply temperature accordingly. The ten ‘rooms’ running into the MVHR unit, as modelled within Apache HVAC are shown below:

Fig 21Fig 21Fig 21Fig 21. Air tube modelling within Apache . Air tube modelling within Apache . Air tube modelling within Apache . Air tube modelling within Apache HVACHVACHVACHVAC

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2.72.72.72.7.8 MVHR Summer.8 MVHR Summer.8 MVHR Summer.8 MVHR Summertime Bytime Bytime Bytime By----pass Damper Controlpass Damper Controlpass Damper Controlpass Damper Control A summer-time bypass damper is present within The PAUL Novus 300 MVHR unit. It is advised that whichever unit is selected, a by-pass damper should be present. The heat recovery matrix is assigned to provide a heat recovery efficiency of 93% when active. The heat recovery matrix by-pass damper is assigned to be regulated dependent upon the extract air temperature. Where the extract air is 24°C, as follows;

Note: The ventilation system description within this element of the report is intended to aid in the The ventilation system description within this element of the report is intended to aid in the The ventilation system description within this element of the report is intended to aid in the The ventilation system description within this element of the report is intended to aid in the design of the system, but should not be considered a substitute for a complete system design. design of the system, but should not be considered a substitute for a complete system design. design of the system, but should not be considered a substitute for a complete system design. design of the system, but should not be considered a substitute for a complete system design. It is advised that an appropriate ventilation systems desIt is advised that an appropriate ventilation systems desIt is advised that an appropriate ventilation systems desIt is advised that an appropriate ventilation systems designer is appointed to undertake detailed igner is appointed to undertake detailed igner is appointed to undertake detailed igner is appointed to undertake detailed design of the system, which may be used to inform future updesign of the system, which may be used to inform future updesign of the system, which may be used to inform future updesign of the system, which may be used to inform future updates to the thermal simulation.dates to the thermal simulation.dates to the thermal simulation.dates to the thermal simulation.

Fig 22Fig 22Fig 22Fig 22. Summer. Summer. Summer. Summer----time heat Recovery Bytime heat Recovery Bytime heat Recovery Bytime heat Recovery By----pass Settingspass Settingspass Settingspass Settings

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2.82.82.82.8 DHW Heating SystemDHW Heating SystemDHW Heating SystemDHW Heating System 2.8.1 DHW Demand Calculations The domestic hot water system is assigned to draw-off hot water from the thermal store located within the plant room (via a heat exchanger) at 60°C, serving taps within the en-suite bathrooms and kitchens. A secondary circulation circuit is not accounted for, owing to the additional thermal losses from such a system. For showers and hand basins, water is likely to be blended down to approx. 45°C at point of use. For washing-up and for baths a flow temperature of up to 65°C may be desired. The following estimations of hot water use have been used within the simulation; Showers;Showers;Showers;Showers;

• 8.5 lts/min - 5 minutes per shower • 42.5ltrs per shower @ 45°C • 29.75lts per shower @60°C

Baths;Baths;Baths;Baths;

• 165 ltrs (Max.) bath at 66.6% capacity • 110ltrs in total @45°C • 77ltrs @ 60°C

Hand Hand Hand Hand basins/Sinks;basins/Sinks;basins/Sinks;basins/Sinks;

• 16ltrs @ 60°C over three periods during the day

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The profile of hot water use is assigned as follows; Master Bedroom EnMaster Bedroom EnMaster Bedroom EnMaster Bedroom En----suite;suite;suite;suite;

Day Number Showers Number Baths Mon 1 1 Tues 2 0 Weds 2 0 Thurs 1 1

Fri 1 1 Sat 2 0 Sun 1 1

Fig 23Fig 23Fig 23Fig 23. Tally of Showers/Baths in Master Bedroom Ensuite. Tally of Showers/Baths in Master Bedroom Ensuite. Tally of Showers/Baths in Master Bedroom Ensuite. Tally of Showers/Baths in Master Bedroom Ensuite

Fig 24Fig 24Fig 24Fig 24. Master Ensuite Shower Day Profile. Master Ensuite Shower Day Profile. Master Ensuite Shower Day Profile. Master Ensuite Shower Day Profile Fig 25Fig 25Fig 25Fig 25. Master Ensuite Bath Day Profile. Master Ensuite Bath Day Profile. Master Ensuite Bath Day Profile. Master Ensuite Bath Day Profile

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Bedroom 4 EnBedroom 4 EnBedroom 4 EnBedroom 4 En----suite;suite;suite;suite;

DayDayDayDay Number ShowersNumber ShowersNumber ShowersNumber Showers Number BathsNumber BathsNumber BathsNumber Baths Mon 2 0 Tues 2 0 Weds 2 0 Thurs 2 0

Fri 2 0 Sat 2 0 Sun 2 0

;

Fig 26Fig 26Fig 26Fig 26. Tally of Showers/Baths in Bedroom 4 Ensuite. Tally of Showers/Baths in Bedroom 4 Ensuite. Tally of Showers/Baths in Bedroom 4 Ensuite. Tally of Showers/Baths in Bedroom 4 Ensuite

Fig 27Fig 27Fig 27Fig 27. Ensuite 4 Shower Day Profile. Ensuite 4 Shower Day Profile. Ensuite 4 Shower Day Profile. Ensuite 4 Shower Day Profile

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Bedroom 3 EnBedroom 3 EnBedroom 3 EnBedroom 3 En----suite;suite;suite;suite;

DayDayDayDay Number ShowersNumber ShowersNumber ShowersNumber Showers Number BathsNumber BathsNumber BathsNumber Baths Mon 1 0 Tues 1 0 Weds 1 0 Thurs 1 0

Fri 1 0 Sat 1 0 Sun 1 0

Hot water consumption within the Bedroom 3 en-suite is only assigned to be active outside of university term time, as follows;

Period Status Jan 1 – Jan 4 Active

Jan 4 – Mar 27 Inactive Mar 27 – Apr 26 Active Apr 26- Jun 17 Inactive Jun 17-Sept 28 Active

Sept 28 – Dec 12 Inactive Dec 12-Dec 31 Active

Fig 28Fig 28Fig 28Fig 28. Tally of Showers/Baths in Bedroom 3 Ensuite. Tally of Showers/Baths in Bedroom 3 Ensuite. Tally of Showers/Baths in Bedroom 3 Ensuite. Tally of Showers/Baths in Bedroom 3 Ensuite

Fig 29Fig 29Fig 29Fig 29. Schedule of Occupied Periods in Bedroom 3 Ensuite. Schedule of Occupied Periods in Bedroom 3 Ensuite. Schedule of Occupied Periods in Bedroom 3 Ensuite. Schedule of Occupied Periods in Bedroom 3 Ensuite Fig 28. Ensuite 3 Shower Day Profile Fig 30Fig 30Fig 30Fig 30. Ensuite 3 Shower Day Profile. Ensuite 3 Shower Day Profile. Ensuite 3 Shower Day Profile. Ensuite 3 Shower Day Profile

29

Guest Bedroom EnGuest Bedroom EnGuest Bedroom EnGuest Bedroom En----suite;suite;suite;suite;

Day Number Showers Number Baths Mon 1 0 Tues 1 0 Weds 1 0 Thurs 1 0

Fri 1 0 Sat 1 0 Sun 1 0

Hot water consumption within the Guest Bedroom en-suite is only assigned to be active, during speculative periods, as follows;

PeriodPeriodPeriodPeriod StatusStatusStatusStatus Jan 1 – Apr 15 Inactive Apr 15- Apr 18 Active Apr 18 – Jul 20 Inactive Jul 20 –Jul 25 Active Jul 25- Dec 23 Inactive Dec 23-Dec 28 Active Dec 28-Dec 31 Inactive

Fig 31.Fig 31.Fig 31.Fig 31. Tally of Showers/Baths in Guest Bedroom EnsuiteTally of Showers/Baths in Guest Bedroom EnsuiteTally of Showers/Baths in Guest Bedroom EnsuiteTally of Showers/Baths in Guest Bedroom Ensuite

Fig 32Fig 32Fig 32Fig 32. Schedule of Occupied Periods in Guest Ensuite. Schedule of Occupied Periods in Guest Ensuite. Schedule of Occupied Periods in Guest Ensuite. Schedule of Occupied Periods in Guest Ensuite Fig 33Fig 33Fig 33Fig 33. Guest Ensuite. Guest Ensuite. Guest Ensuite. Guest Ensuite Shower Day ProfileShower Day ProfileShower Day ProfileShower Day Profile

30

Hand basins/sinks; Hand basins and sinks have been assigned to use 16 ltrs of 60°C hot water at three separate intervals through each day. Depending on the amount that manual washing up etc is carried out, this speculative figure could be high or low and should be validated. Draw off is assigned at 09:00, 13:00 & 19:00.

Totals; The total hot water consumption at 60°C sums 64,240 ltrs per year, or 176 ltrs per day on average. Hot water usage depends highly on the occupant’s behaviour. Reduction in the number of baths taken, and/or water consumed by hand basins etc could reduce this figure. It may be considered to undertake a detailed audit of hot water consumption in order to more accurately access this figure. However, regardless of the figure arrived at, consumption will vary dependent upon occupancy numbers present; therefore any figure is only theoretical. The figures used within this report probably account for the upper end of expected DHW consumption. If Bedroom 4 is more regularly occupied however and more frequent use of the Guest Bedroom occurs, consumption may be greater.

Fig 34Fig 34Fig 34Fig 34. Schedule of Hand basin/sink usage. Schedule of Hand basin/sink usage. Schedule of Hand basin/sink usage. Schedule of Hand basin/sink usage

31

2.8.2 DHW/Space Heating Plant The design intent for the heating system is to provide energy inputs from a roof mounted solar thermal array into a high capacity thermal store located in the plant room. The thermal store will receive supplementary inputs from an additional heat source to cover winter time demand. This additional heat source is at present understood to be a gas fired boiler, though this may be subject to change. From the thermal store, a LTHW radiator circuit shall serve radiators identified section 2.6.1 of the report. It is suggested that this operates via a thermostatic blending valve to regulate the flow temperature to 45°C as discussed within Section 2.6.1 of the report. Domestic hot water shall enter a heat exchanger at the top of the thermal store, extracting energy from the highest temperature water, before exiting the heat exchanger via a thermostatic blending valve set to 60-65°C. The system assembly shall be similar to that pictured below (as modelled within T*Sol software);

Fig 35. Schematic of single Store Solar Thermal System

32

Domestic hot water plant has been modelled within the IES Apache HVAC systems simulation interface. Doing so allows modelling to take place where by the solar thermal collectors are able to be accounted for within the space heating system, as required. The system assembly is shown below;

The solar thermal collectors are modelled using the following parameters;

Fig 36Fig 36Fig 36Fig 36. Schematic of Heating System with ApacheHVAC. Schematic of Heating System with ApacheHVAC. Schematic of Heating System with ApacheHVAC. Schematic of Heating System with ApacheHVAC

Fig 37Fig 37Fig 37Fig 37. ApacheHVAC. ApacheHVAC. ApacheHVAC. ApacheHVAC Solar Thermal ParametersSolar Thermal ParametersSolar Thermal ParametersSolar Thermal Parameters

33

Of particular importance are;

• The collector area (modelled as 11.52m²) • Azimuth (modelled at 180°; due south) • Tilt (modelled at 90°) • The conversion efficiency at ambient temperature (modelled at 65%)

Panels should be selected with the highest conversion efficiency as available. The thermal store is assigned at 500ltrs capacity (though other capacities are assessed later within the report). Typical thermal losses from a store of this size have been accounted for. The system as modelled within the software does not completely mirror the assembly of the system in practice. Stratification is not modelled with the thermal store – the store is calculated as a volume at a single temperature. In practice, this would not occur – higher temperature water will migrate to the top of the cylinder and displace colder water to the bottom, a process known as stratification. Further, the system is modelled such that the tank is heated via the solar thermal system (at a single temperature –stratification is not modelled). The DHW is taken from the cylinder (required at 60°C) and if of an insufficiently temperature, shall be heated via the gas boiler. As the average thermal store temperature sits around 45°C, the simulation accounts for ‘top-up’ to 60°C through much of the year. This is not likely to occur in practice, as the top of the thermal store, from which DHW is extracted (via a heat exchanger), is likely to be up to 60°C via solar thermal heating inputs for much of the year. For this reason, the IES model has been used for space heating loads and a variety of further analysis which are independent from energy generation, however further analysis using T*Sol software, which does account for tank stratification, has been used for interrogation of the solar thermal system.

34

2.92.92.92.9 Internal Gains; Occupants, Lighting & EquipmentInternal Gains; Occupants, Lighting & EquipmentInternal Gains; Occupants, Lighting & EquipmentInternal Gains; Occupants, Lighting & Equipment Internal gains resulting from occupants, lighting and equipment have been modelled based on information provided by the client. As the principle purpose of this assessment is to assess the heating plant sizing for the building, equipment gains have not been accounted for, as these will displace heating demand. The following peak gains are associated with each room;

Room Lighting Equipment Occupants Power (W)

Schedule Power (W) Schedule (Nr) Schedule

-01 Reception 56 A 0 - 2 A -01 Bedroom 3 42 B 0 - 1 B -01 Bedroom 3 En-suite 21 C 0 - 1 C -01 Bedroom 4 42 D 0 - 2 D -01 Bedroom 4 En-suite 21 E 0 - 1 E -01 Corridor/Stair 0 - 0 - 0 - -01 Airing Cup’d 0 - 0 - 0 - -01 Linen Cup’d 0 - 0 - 0 - -01 Plant Room 0 - 0 - 0 - 00 Lobby 14 F 0 - 0 - 00 Guest En-suite 21 G 0 - 1 G 00 Utility Kitchen 42 H 0 - 1 H 00 Study/Office 68 I 0 - 1 I 00 Cup’d 0 - 0 - 0 - 00 Guest Bedroom 42 J 0 - 2 J 00 Larder/Riser 0 - 0 - 0 - 00 Cup’d/Riser 0 - 0 - 0 - 00 Entrance Hall 42 F 0 - 0 - 00 Kitchen 56 H 0 - 3* K 00 Dining 28 H 0 - 3* K 00 Main Reception 104 H 0 - 3* K 00 Entrance Lobby 0 - 0 - 0 - 01 Master Bedroom 42 D 0 - 2 D 01 Master En-suite 21 E 0 - 1 E

Fig 38Fig 38Fig 38Fig 38. Peak . Peak . Peak . Peak Occupancy and Lighting GainsOccupancy and Lighting GainsOccupancy and Lighting GainsOccupancy and Lighting Gains

35

2.9.1 2.9.1 2.9.1 2.9.1 Lighting SchedulesLighting SchedulesLighting SchedulesLighting Schedules The following variation profiles have been applied to lighting within each room (as indicated within fig.36 above). Lighting takes account of lesser use within the summer, using separate profiles for winter, spring/autumn &summer. A; Reception Lighting Yr; Operation Annual

Winter Autumn/Spring Summer

B; Bedroom 3 Lighting Yr; Operation Restricted to Occupied Periods Only


C; Bedroom 3 En-suite Lighting Yr; Operation Restricted to Occupied Periods Only


Fig 39Fig 39Fig 39Fig 39. Lighting Schedules. Lighting Schedules. Lighting Schedules. Lighting Schedules

36

D; Master Bedroom/Bedroom 4 Lighting Yr; Operation Annual Winter Autumn/Spring Summer

E; Master Bedroom En-suite/Bedroom 4 En-suite Lighting Yr; Operation Annual


F-Circulation Areas Lighting; Operation Annual


G- Guest En-suite Lighting Yr; Operation Restricted to Occupied Periods


37

H-Kitchen/Dining/Main Reception Lighting Yr; Operation Annual Winter Autumn/Spring Summer

I- Study Lighting Yr; Operation Restricted to Mon, Tue, Weds, Fri Only


J-Guest Bedroom Lighting Yr; Operation Restricted to Occupied Periods

Winter Autumn/Spring Winter

38

2.9.2 Occupancy Schedules The following variation profiles have been applied to occupancy gains. These profiles tie-in with the profiles also used for lighting and DHW consumption, as follows; A; Reception Occ Yr; Occupation Annual

Weekdays & Weekends -

B; Bedroom 3 Occ Yr; Restricted to Occupied periods Defined in Fig. 29 Weekdays & Weekends -

C; Bedroom 3 En-suite Occ Yr; Restricted to Occupied Periods Defined in Fig. 29 Weekdays & Weekends -

Fig 40Fig 40Fig 40Fig 40. Occupancy Schedules. Occupancy Schedules. Occupancy Schedules. Occupancy Schedules

39

D; Master Bedroom/Bedroom 4 Occ Yr; Occupation Annual Weekdays & Weekends -

E; Master Bedroom En-suite/Bedroom En-suite 4 Occ Yr; Occupation Annual Weekdays & Weekends -

G-Guest En suite Occ Yr; Restricted to Occupied Periods Defined in Fig. 32 Weekdays & Weekends -

H-Kitchen/Dining/Main Reception Occ – Occupation Annual

Weekdays & Weekends -

40

I- Study Occ Yr; Operation Restricted to Mon, Tue, Weds, Fri Only Mon, Tues, Weds, Fri Thurs, Sat, Sun

Not Occupied

J- Guest Bedroom Occ yr; Restricted to Occupied Periods Defined in Fig. 32 Weekdays & Weekends -

K-Kitchen/Dining/Main Reception Occ Yr Days within periods defined within table X. Other days

41

2.10 Humidity Gains and CO2 Levels 2.10.1 Humidity gains In order to simulate the effect of humidity gains as the consequence of showing, bathing and cooking, humidity gains have been added within the simulation based upon CIBSE Guide A guidance. Showering is accounted to add 0.001kg/s up to 100% humidity based upon DHW demand profiles within en-suites. Cooking accounts for the same levels of humidity based upon the Kitchen DHW use profile. Humidity gains do not represent a cooling effect through evaporation. 2.10.2 Vapour gains The effect of drying clothes within the airing cupboard has been accounted for. It is assumed that 3.Nr 24hr periods of clothes drying will occur per week, where external temperatures are

42

2.112.112.112.11 Control of Windows & DoorsControl of Windows & DoorsControl of Windows & DoorsControl of Windows & Doors Control of Windows; Windows which are identified to be opening windows are assigned to be opened to 10° when the external air temperature is >17°C. Windows are assigned to open gradually, being fully open when the external air temperature is >19°C. When the external air temperature exceeds 22°C windows are assigned to be shut. By automating MVHR controls, the ventilation system will automatically reduce the flow rate when windows are opened, unless windows remain open and the internal temperature rises. The cooling philosophy for the building is to shut windows when external temperatures exceed 22°C and provide cooler ventilation air via the earth tube. As such, it would be prudent to provide an indicator inside the house which indicates whether it is suitable to open or close windows. Internal doors are assigned to remain shut in most cases and remain open in the case of the utility kitchen and lobby. External doors are assigned to remain shut. All internal doors account for an air gap equal to 0.5% of the door area to allow the flow of ventilation between rooms. It is of high importance that this air gap is included.It is of high importance that this air gap is included.It is of high importance that this air gap is included.It is of high importance that this air gap is included. Louvered doors are accounted for on the speculative airing cupboard.

43

3.0 Simulation Results The building has been simulated based upon the parameters detailed within Section 2 of this report. It should be observed that occupancy templates used for DHW demand may be subject to change through variations in the building’s occupancy levels and these results only provide an indicative impression of the actual scenarios. This initial assessment is based upon vertically orientated solar collectors covering 11.52m², with a 1500ltr thermal store. Further investigations into the performance of the building through changes to the specification are described with Section 4 of the report.

44

3.1 Study into Available Solar Energy The design philosophy of the building is to utilise solar energy via evacuated tube solar thermal collectors and ‘bank’ this energy using a thermal store, for use when required. As such, the solar energy which falls upon the roof of the build is of great importance, as this governs the quota of energy which is available for providing for space heating and DHW demand. Unless the thermal store is very large, where solar gains are less than space heating and DHW demand for weeks or months at a time, it is not possible to yield sufficient energy from the solar system to provide for demand. At such times, supplementary heating is necessary. A study has been conducted into the solar energy falling on the roof of the building, and that absorbed through the vertically inclined collectors. The solar energy on the roof is of interest as these calculations are independent from the calculations carried out to model the solar thermal system itself –which within IES may not be fully representative. Section 3.02 assesses this energy generation in comparison to the space heating and DHW demand. The following images display solar gains on the building in terms of total energy yield (kWh) for both clear sky days and diffuse sky (cloud cover) days;

45

Fig 41Fig 41Fig 41Fig 41. . . . Calculated solar gains on building exterior; Annual Calculated solar gains on building exterior; Annual Calculated solar gains on building exterior; Annual Calculated solar gains on building exterior; Annual –––– Clear Sky (kWh/m²)Clear Sky (kWh/m²)Clear Sky (kWh/m²)Clear Sky (kWh/m²)

Fig. 42Fig. 42Fig. 42Fig. 42 Calculated solar gains on building exterior; Calculated solar gains on building exterior; Calculated solar gains on building exterior; Calculated solar gains on building exterior; Annual Annual Annual Annual –––– Diffuse Sky (kWh/m²)Diffuse Sky (kWh/m²)Diffuse Sky (kWh/m²)Diffuse Sky (kWh/m²)

Fig.43Fig.43Fig.43Fig.43 Calculated solar gains on building exterior; January Calculated solar gains on building exterior; January Calculated solar gains on building exterior; January Calculated solar gains on building exterior; January –––– Clear Sky (kWh/m²)Clear Sky (kWh/m²)Clear Sky (kWh/m²)Clear Sky (kWh/m²)

46

Fig. 44Fig. 44Fig. 44Fig. 44 Calculated solar gains on building exterior; January Calculated solar gains on building exterior; January Calculated solar gains on building exterior; January Calculated solar gains on building exterior; January –––– Diffuse Sky (kWh/m²)Diffuse Sky (kWh/m²)Diffuse Sky (kWh/m²)Diffuse Sky (kWh/m²)

Fig. 45Fig. 45Fig. 45Fig. 45 Calculated solar gains on building Calculated solar gains on building Calculated solar gains on building Calculated solar gains on building exterior; July exterior; July exterior; July exterior; July –––– Clear Sky (kWh/m²)Clear Sky (kWh/m²)Clear Sky (kWh/m²)Clear Sky (kWh/m²)

Fig. 46Fig. 46Fig. 46Fig. 46 Calculated solar gains on building exterior; July Calculated solar gains on building exterior; July Calculated solar gains on building exterior; July Calculated solar gains on building exterior; July –––– Diffuse Sky (kWh/m²)Diffuse Sky (kWh/m²)Diffuse Sky (kWh/m²)Diffuse Sky (kWh/m²)

47

Radiation flux upon the roof (W/m²) is shown in the table below. Note the distinctively different flux profiles through the year. The main roof receives lower radiation during Nov, Dec, Jan & Feb, but significantly higher yields through the rest of the year. The radiation flux on the vertical section of the roof achieves its highest peaks during the spring and autumn, with the summer flux achieving the lowest peaks through the year. This is due to the vertical plane being orientated more directly at the sun during the winter.

Radiation flux upon the roof: AnnualRadiation flux upon the roof: AnnualRadiation flux upon the roof: AnnualRadiation flux upon the roof: Annual Radiation flux upon main roof Radiation flux upon main roof Radiation flux upon main roof Radiation flux upon main roof (W/m²)(W/m²)(W/m²)(W/m²)

Radiation flux upon vertical element of (W/m²)Radiation flux upon vertical element of (W/m²)Radiation flux upon vertical element of (W/m²)Radiation flux upon vertical element of (W/m²)

Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec Jan

900

800

700

600

500

400

300

200

100

0

Ra

dia

tio

n flu

x (

W/m

²)

Date: Mon 01/Jan to Mon 31/Dec


600

550

500

450

400

350

300

250

200

150

100

50

0

Ra

dia

tio

n flu

x (

W/m

²)


Fig 47Fig 47Fig 47Fig 47. Radiation Flux upon Roof. Radiation Flux upon Roof. Radiation Flux upon Roof. Radiation Flux upon Roof

48

The table and graph below display the available solar energy upon separate elements of the south facing roof;

Solar Energy on Roof; Cloud Cover Mix -Based on Weather Template MonthMonthMonthMonth Solar Energy & Power

Upon South Facing Main Roof

Solar Energy & Power Upon Vertical Element of

South Facing Roof

Solar Energy & Power Upon Entire South

Facing Roof Solar Energy (kWh)

Peak Solar gain (kW)

Solar Energy (kWh)


Solar Energy (kWh)


Jan 2,681.3 40.17 393.2 6.19 3,074.5 46.36 Feb 3,559.2 44.4 457.8 6.30 4017 50.7 March 5292 52.14 568 6.25 5,860 58.39 April 8,425.3 59.67 739.4 5.68 9,164.7 65.35 May 9,340.5 61.39 694.6 4.89 10,035.1 66.28 June 10,103.4 61.96 720 4.37 10,823.4 66.33 July 9,247.9 61.64 688.1 4.74 9,936 66.38 August 8,984.4 59.95 730.4 5.45 9,714.8 65.4 September 7,380.9 38.23 731.9 6.05 8,112.8 44.28 October 4,987.4 52.09 598.6 6.26 5,586 58.35 November 2,848.1 41.91 401 6.27 3,249.1 48.18 December 2,401.1 34.54 379.3 5.89 2,780.4 40.43 Total 75,251.4 n/a 7,102.3 n/a 82,353.7 n/a

0.00

2,000.00

4,000.00

6,000.00

8,000.00

10,000.00

12,000.00

Jan Feb Mar Apr May Jun Jul Aug Sept Oct Nov Dec

Available Solar Energy on Roof (kWh)

Vertical Roof Solar

Energy (kWh)

Main Roof Solar

Energy (kWh)

Fig 48. Table of Assessed Solar Energy upon Roof

Fig 49Fig 49Fig 49Fig 49. Graph of Assessed Solar Energy upon Roof. Graph of Assessed Solar Energy upon Roof. Graph of Assessed Solar Energy upon Roof. Graph of Assessed Solar Energy upon Roof

49

3.3.3.3.2 Study into th2 Study into th2 Study into th2 Study into the Assessed Space e Assessed Space e Assessed Space e Assessed Space Heating & DHW DHeating & DHW DHeating & DHW DHeating & DHW Demandemandemandemand The simulation has been used to assess the space heating loads within the building. The following results have been produced;

Date

Rads Ventilation System Heating

Coil Total

kWh kW peak

kW mean kWh

kW peak

kW mean kWh

kW peak

kW mean

Jan 719.70 3.07 0.97 242.50 0.91 0.33 962.20 3.98 1.29 Feb 422.10 1.61 0.06 186.60 0.90 0.27 608.70 2.51 0.33 Mar 396.80 1.40 0.53 165.00 0.83 0.22 561.80 2.22 0.75 Apr 56.80 2.03 0.08 21.20 0.83 0.03 78.00 2.86 0.11 May 16.80 0.08 0.02 0.00 0.00 0.00 16.80 0.08 0.02 Jun 15.00 0.12 0.02 0.00 0.00 0.00 15.00 0.12 0.02 Jul 18.20 0.15 0.02 0.00 0.00 0.00 18.20 0.15 0.02 Aug 15.70 0.16 0.02 0.00 0.00 0.00 15.70 0.16 0.02 Sept 15.40 0.10 0.02 0.00 0.00 0.00 15.40 0.10 0.02 Oct 110.80 2.70 0.15 7.00 0.65 0.01 117.80 3.35 0.16 Nov 487.90 1.67 0.68 116.30 0.73 0.16 604.20 2.41 0.84 Dec 579.60 1.94 0.78 225.50 0.75 0.30 805.10 2.69 1.08

Annual Annual Annual Annual TotalTotalTotalTotal 2854.92854.92854.92854.9 964.2964.2964.2964.2 3819.13819.13819.13819.1

The simulation has been used to assess the DHW loads within the building. The following results have been produced;

Date DHW Demand

kWh kW peak kW mean Jan 447.3 15.99 0.60 Feb 397.9 10.42 0.59 Mar 449.4 15.99 0.60 Apr 488.2 26.35 0.68 May 439.1 10.42 0.59 Jun 453 15.99 0.63 Jul 515.7 26.36 0.69 Aug 505.4 15.99 0.67 Sept 484.1 15.99 0.67 Oct 439.1 10.42 0.59 Nov 428.1 10.42 0.59 Dec 490.9 26.36 0.66

Annual Annual Annual Annual TotalTotalTotalTotal 5538.15538.15538.15538.1 ---- ----

Fig 50Fig 50Fig 50Fig 50. Table of Assessed Space Heating Demand. Table of Assessed Space Heating Demand. Table of Assessed Space Heating Demand. Table of Assessed Space Heating Demand

Fig 51Fig 51Fig 51Fig 51. Table of Assessed DHW Demand. Table of Assessed DHW Demand. Table of Assessed DHW Demand. Table of Assessed DHW Demand

50

The following results are achieved when both space heating demand and DHW demand are combined;

Date Space Heating Demand DHW Demand

Space Heating and DHW Combined Energy Demand

kWh kWh kWh Jan 962.20 447.3 1409.50 Feb 608.70 397.9 1006.60 Mar 561.80 449.4 1011.20 Apr 78.00 488.2 566.20 May 16.80 439.1 455.90 Jun 15.00 453 468.00 Jul 18.20 515.7 533.90 Aug 15.70 505.4 521.10 Sept 15.40 484.1 499.50 Oct 117.80 439.1 556.90 Nov 604.20 428.1 1032.30 Dec 805.10 490.9 1296.00

Annual Annual Annual Annual TotalTotalTotalTotal 3819.13819.13819.13819.1 5538.15538.15538.15538.1 9357.209357.209357.209357.20

Conclusions: Aggregated across the year, when based on the modelled parameters, DHW represents an energy demand approximately 45% more than that of space heating. During the heating season, space heating demand reaches a maximum demand within a single month approximately 54% greater than the DHW demand.

0

200

400

600

800

1000

1200

1400

1600

Jan Feb Mar Apr May Jun Jul Aug Sept Oct Nov Dec

kW

h

Month

Assessed Space Heating and DHW Demand (kWh)

DHW

Demand

(kWh)

Space

Heating

Demand

(kWh)

Fig 52Fig 52Fig 52Fig 52. Table of Assessed Combined Space Heating and DHW Demand. Table of Assessed Combined Space Heating and DHW Demand. Table of Assessed Combined Space Heating and DHW Demand. Table of Assessed Combined Space Heating and DHW Demand

Fig 53Fig 53Fig 53Fig 53. Table of Assessed Combined Space Heating and DHW Demand. Table of Assessed Combined Space Heating and DHW Demand. Table of Assessed Combined Space Heating and DHW Demand. Table of Assessed Combined Space Heating and DHW Demand

51

3.3 Study into the relationship between Energy Demand and Available Energy Generation

From section 3.01 and 3.02 of the report, we can conclude the following;

Date


Solar Energy Upon Entire South Facing Roof

(kWh) (kWh) Jan 1409.50 3,074.5 Feb 1006.60 4017 Mar 1011.20 5,860 Apr 566.20 9,164.7 May 455.90 10,035.1 Jun 468.00 10,823.4 Jul 533.90 9,936 Aug 521.10 9,714.8 Sept 499.50 8,112.8 Oct 556.90 5,586 Nov 1032.30 3,249.1 Dec 1296.00 2,780.4

Annual TotalAnnual TotalAnnual TotalAnnual Total 9357.209357.209357.209357.20 82,353.782,353.782,353.782,353.7 Conclusions: Sufficient solar energy falls upon the roof of the building within any single month to supply the energy demands calculated within the simulation. However, the efficiency of converting this energy into useful heat shall govern the ability of the building to operate using solar energy alone.

Fig 54Fig 54Fig 54Fig 54. Comparison of Combined Space and DHW Demand with Available Solar Gains on South Roof. Comparison of Combined Space and DHW Demand with Available Solar Gains on South Roof. Comparison of Combined Space and DHW Demand with Available Solar Gains on South Roof. Comparison of Combined Space and DHW Demand with Available Solar Gains on South Roof

52

3.3.3.3.4444 Assessing the Energy Generation Available from Solar TechnologiesAssessing the Energy Generation Available from Solar TechnologiesAssessing the Energy Generation Available from Solar TechnologiesAssessing the Energy Generation Available from Solar Technologies Due to the aforementioned limitations with solar thermal calculations conducted within IES, Valentin T*Sol software has been selected for detailed analysis of the solar thermal system. A system has been modelled accounting for 4Nr. IVT 18 CPC evacuated tube panels (as previously specified), at a vertical inclination, in combination with a 500ltr thermal store. The available yield from a PV array, measuring 5m x 10.6m has been calculated within IES, using the following parameters for the PV panel specification. Note that the array area indicated is for the total active area of the collectors; a reduction in the area should be applied where the panel frame reduces the collector area;

It is assumed that generation via the PV array will be fed into the thermal store via immersion heaters at 100% efficiency. The following results are calculated;

Date

Energy generation of Solar Thermal System (calculated in T*Sol)

Energy generation of Solar PV System (calculated in IES)

Total generation

through Solar Technologies

(kWh) (kWh) (kWh) Jan 229.33 297.8 527.13 Feb 249.05 391.5 640.55 Mar 361.05 576.8 937.85 Apr 383.98 895.6 1279.58 May 241.56 976.2 1217.76 Jun 242.08 1045.5 1287.58 Jul 236.64 956.9 1193.54 Aug 268.65 926.3 1194.95 Sept 298.72 773.9 1072.62 Oct 417.79 535.5 953.29 Nov 272.16 312.1 584.26 Dec 173.92 265.7 439.62

Annual TotalAnnual TotalAnnual TotalAnnual Total 3,374.933,374.933,374.933,374.93 7,953.87,953.87,953.87,953.8 11,328.7311,328.7311,328.7311,328.73

Fig 55Fig 55Fig 55Fig 55. Parameters for PV Array Input into IES Simulation. Parameters for PV Array Input into IES Simulation. Parameters for PV Array Input into IES Simulation. Parameters for PV Array Input into IES Simulation

Fig 56Fig 56Fig 56Fig 56. Total Energy Generation through Solar Technologies as Calculated within IES. Total Energy Generation through Solar Technologies as Calculated within IES. Total Energy Generation through Solar Technologies as Calculated within IES. Total Energy Generation through Solar Technologies as Calculated within IES

53

3.5 Assessing the Ability of Solar Technologies to Meet Assessed Heating Demands

From sections 3.02 and 3.04 we can deduce that;

Date


Total generation

through Solar Technologies

Energy deficit/surplus

Energy Required by Supplementary heat Source

(kWh) (kWh) (kWh) (kWh) Jan 1409.50 527.13 -882.37 882.37 Feb 1006.60 640.55 -366.05 366.05 Mar 1011.20 937.85 -73.35 73.35 Apr 566.20 1279.58 +713.38 0.00 May 455.90 1217.76 +761.86 0.00 Jun 468.00 1287.58 +819.58 0.00 Jul 533.90 1193.54 +659.64 0.00 Aug 521.10 1194.95 +673.85 0.00 Sept 499.50 1072.62 +573.12 0.00 Oct 556.90 953.29 +396.39 0.00 Nov 1032.30 584.26 -448.04 448.04 Dec 1296.00 439.62 -856.38 856.38

Annual TotalAnnual TotalAnnual TotalAnnual Total 9357.209357.209357.209357.20 11,328.7311,328.7311,328.7311,328.73 +1,971.53 2,626.19 ConclusionsConclusionsConclusionsConclusions:::: Based on the parameters input into the assessments, it can be expected that based upon the proposed specification, the building shall be self-sufficient for space heating and DHW generation from April to October. This accounts for 4Nr IVT 18 CPC collectors, orientated vertically, a 1500ltr thermal store and 53m² of PV panels at a 30° inclination. Supplementary energy inputs will be required between November and March. The solar PV system will operate at a surplus during April-October, thus allowing export to the grid. The energy generation from both the solar technologies is calculated to provide 72% of the total annual space heating and DHW energy demand.

Fig 57Fig 57Fig 57Fig 57. Total Energy Generation through Solar Technologies as Calculated within IES. Total Energy Generation through Solar Technologies as Calculated within IES. Total Energy Generation through Solar Technologies as Calculated within IES. Total Energy Generation through Solar Technologies as Calculated within IES

54

3.5.1 Study into Local Space Heating Demand The thermal simulation is assembled in order to provide a minimum internal temperature of +18°C. Based on simulation inputs described within Section 2 of the report, the following radiator and ventilation system heater battery peak heating loads have been calculated. It would be prudent to apply an over sizing factor (circa 20%) to these calculations. Also note that it is intended that the LTHW circuit shall run as 45°C, therefore all radiators should be oversized accordingly.

Room Max. Output

(kW) Max. Output

Time Mean Output

(kW)

00 Lobby 0.843 04:51,10/Jan 0.004

00 Utility Kitchen 0.442 06:27,24/Oct 0.035

00 Study/Office 0.542 17:09,11/Jan 0.033

00 Guest Room 0.575 16:57,11/Jan 0.026

01 Master Bedroom 0.524 17:21,11/Jan 0.027

-01 Bedroom 3 0.154 06:27,08/Jan 0.004

01 Bedroom 4 0.307 16:45,02/Dec 0.004

01 Reception 0.456 07:03,07/Jan 0.007

00 Main Reception 1.192 13:33,09/Jan 0.185

Ventilation System Heater Battery 0.913 00.33, 09/Jan 0.110

Fig 58. Peak and Mean Space Heating Loads by Room as Calculated within IES

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3.5.2 Study into Internal Temperatures Internal temperatures have been assessed within the simulation. The graph below indicates the internal temperatures within the building when simulated using the CIBSE Southampton Typical Reference Year 05 weather file.

A second simulation has been run using the CIBSE Southampton Design Summer Year 05 weather file, which accounts for higher summer time temperatures. The following results are achieved;


30

28

26

24

22

20

18

16

Te

mpera

ture

(°C

)


Air temperature: 00 Lobby (HILLSIDE Vertical 11.52 Panel Only U=0.10 500ltr store .aps) Air temperature: 00 Guest Ensuite (HILLSIDE Vertical 11.52 Panel Only U=0.10 500ltr store .aps)

Air temperature: 00 Utility Kitchen (HILLSIDE Vertical 11.52 Panel Only U=0.10 500ltr store .aps) Air temperature: 00 Study/Office (HILLSIDE Vertical 11.52 Panel Only U=0.10 500ltr store .aps)

Air temperature: 00 Guest Room (HILLSIDE Vertical 11.52 Panel Only U=0.10 500ltr store .aps) Air temperature: 01 Master Bedroom (HILLSIDE Vertical 11.52 Panel Only U=0.10 500ltr store .aps)

Air temperature: 00 Entrance Hall (HILLSIDE Vertical 11.52 Panel Only U=0.10 500ltr store .aps) Air temperature: 01 Master Ensuite (HILLSIDE Vertical 11.52 Panel Only U=0.10 500ltr store .aps)

Air temperature: -01 Bedroom 3 (HILLSIDE Vertical 11.52 Panel Only U=0.10 500ltr store .aps) Air temperature: -01 Bedroom 3 Ensuite (HILLSIDE Vertical 11.52 Panel Only U=0.10 500ltr store .aps)

Air temperature: -01 Bedroom 4 Ensuite (HILLSIDE Vertical 11.52 Panel Only U=0.10 500ltr store .aps) Air temperature: -01 Bedroom 4 (HILLSIDE Vertical 11.52 Panel Only U=0.10 500ltr store .aps)

Air temperature: -01 Reception (HILLSIDE Vertical 11.52 Panel Only U=0.10 500ltr store .aps) Air temperature: -01 Corridor/Stair (HILLSIDE Vertical 11.52 Panel Only U=0.10 500ltr store .aps)

Air temperature: 00 Kitchen (HILLSIDE Vertical 11.52 Panel Only U=0.10 500ltr store .aps) Air temperature: 00 Dining (HILLSIDE Vertical 11.52 Panel Only U=0.10 500ltr store .aps)

Air temperature: 00 Main Reception (HILLSIDE Vertical 11.52 Panel Only U=0.10 500ltr store .aps)


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25

24

23

22

21

20

19

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17

16

Te

mp

era

ture

(°C

)


Air temperature: 00 Lobby (HILLSIDE DSY Vertical 11.52 Panel Only U=0.10 500ltr store .aps) Air temperature: 00 Guest Ensuite (HILLSIDE DSY Vertical 11.52 Panel Only U=0.10 500ltr store .aps)

Air temperature: 00 Utility Kitchen (HILLSIDE DSY Vertical 11.52 Panel Only U=0.10 500ltr store .aps) Air temperature: 00 Study/Office (HILLSIDE DSY Vertical 11.52 Panel Only U=0.10 500ltr store .aps)

Air temperature: 00 Guest Room (HILLSIDE DSY Vertical 11.52 Panel Only U=0.10 500ltr store .aps) Air temperature: 01 Master Bedroom (HILLSIDE DSY Vertical 11.52 Panel Only U=0.10 500ltr store .aps)

Air temperature: 00 Entrance Hall (HILLSIDE DSY Vertical 11.52 Panel Only U=0.10 500ltr store .aps) Air temperature: 01 Master Ensuite (HILLSIDE DSY Vertical 11.52 Panel Only U=0.10 500ltr store .aps)

Air temperature: -01 Bedroom 3 (HILLSIDE DSY Vertical 11.52 Panel Only U=0.10 500ltr store .aps) Air temperature: -01 Bedroom 3 Ensuite (HILLSIDE DSY Vertical 11.52 Panel Only U=0.10 500ltr store .aps)

Air temperature: -01 Bedroom 4 Ensuite (HILLSIDE DSY Vertical 11.52 Panel Only U=0.10 500ltr store .aps) Air temperature: -01 Bedroom 4 (HILLSIDE DSY Vertical 11.52 Panel Only U=0.10 500ltr store .aps)

Air temperature: -01 Reception (HILLSIDE DSY Vertical 11.52 Panel Only U=0.10 500ltr store .aps) Air temperature: -01 Corridor/Stair (HILLSIDE DSY Vertical 11.52 Panel Only U=0.10 500ltr store .aps)

Air temperature: 00 Kitchen (HILLSIDE DSY Vertical 11.52 Panel Only U=0.10 500ltr store .aps) Air temperature: 00 Dining (HILLSIDE DSY Vertical 11.52 Panel Only U=0.10 500ltr store .aps)

Air temperature: 00 Main Reception (HILLSIDE DSY Vertical 11.52 Panel Only U=0.10 500ltr store .aps)

Fig 59Fig 59Fig 59Fig 59. Graph of . Graph of . Graph of . Graph of Internal Temperatures using Southampton TRY weather fileInternal Temperatures using Southampton TRY weather fileInternal Temperatures using Southampton TRY weather fileInternal Temperatures using Southampton TRY weather file

Fig Fig Fig Fig 60606060. Graph of Internal Temperatures using Southampton DSY weather file. Graph of Internal Temperatures using Southampton DSY weather file. Graph of Internal Temperatures using Southampton DSY weather file. Graph of Internal Temperatures using Southampton DSY weather file

56

Room Occupied time 26°C (%)

Occupied time >28°C

(%)

CIBSE Guide A compliant?

00 Lobby 0.0 0 0 YES 00 Guest En-suite 0.0 0 0 YES 00 Utility Kitchen 0.0 0.4 0 YES 00 Study/Office 0.0 0 0 YES 00 Guest Room 0.0 0 0 YES

01 Master Bedroom 0.0 0.2 0 YES 00 Entrance Hall 0.0 0 0 YES

01 Master En-suite 0.3 0.5 0.1 YES -01 Bedroom 3 0.0 0 0 YES

-01 Bedroom 3 En-suite 0.0 0 0 YES -01 Bedroom 4 En-suite 0.0 0 0 YES

-01 Bedroom 4 0.0 0 0 YES -01 Reception 0.0 0.4 0 YES

-01 Corridor/Stair 0.0 0 0 YES 00 Kitchen 0.5 1 0.1 YES 00 Dining 0.5 1 0.1 YES

00 Main Reception 0.3 1 0.1 YES

Room Occupied time 26°C (%)

Occupied time >28°C

(%)

CIBSE Guide A compliant?

00 Lobby 0 0 0 YES 00 Guest En-suite 0 0 0 YES 00 Utility Kitchen 0 0.2 0 YES 00 Study/Office 0 0 0 YES 00 Guest Room 0 0 0 YES

01 Master Bedroom 0 0 0 YES 00 Entrance Hall 0 0 0 YES

01 Master En-suite 0.3 0 0 YES -01 Bedroom 3 0 0 0 YES

-01 Bedroom 3 En-suite 0 0 0 YES -01 Bedroom 4 En-suite 0 0 0 YES

-01 Bedroom 4 0 0 0 YES -01 Reception 0 0.1 0 YES

-01 Corridor/Stair 0 0 0 YES 00 Kitchen 0.6 1 0 YES 00 Dining 0.5 1 0 YES

00 Main Reception 0.5 1.1 0 YES

Conclusions: Based on the parameters input into the assessments, all areas will remain above 18°C for >99.5% of occupied time. So long as windows and doors are shut during periods where external air temperatures are >22°C, over heating is highly unlikely.

Fig 61Fig 61Fig 61Fig 61. Table of Internal Temperatures using Southampton TRY weather file. Table of Internal Temperatures using Southampton TRY weather file. Table of Internal Temperatures using Southampton TRY weather file. Table of Internal Temperatures using Southampton TRY weather file

Fig 62. Table of Internal Temperatures using Southampton DSY weather file

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3.5.3 Study into the Performance of the Earth Tube and MVHR unit The PAUL Novus 300 MVHR will tolerate supply air temperatures of -8°C. Other MVHR units may not tolerate such conditions. The function of the earth tube is to provide frost protection to the MVHR unit, to avoid the risk of drawing air into the system which is too cold. It also provides the role of heating the incoming air supply to reduce heating demand, and also cooling the incoming air supply to provide space cooling via the ventilation system during the summer. The earth tube has been modelled as 10Nr 200mm dia. Chambers, through which the air supply to the MVHR unit is drawn. The graph below displays the air temperature as it passes through the duct, with the green line indicating the entry temperature and the blue line showing the exit temperature – as it passes into the MVHR unit.

Conclusions: An earth tube of 10m in length with a dia. Of 200mm will be sufficient to raise the incoming air temperature to not less than 3°C. A longer earth tube will be necessary if the MVHR unit cannot tolerate temperatures

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The flow rate through the MVHR unit is shown in the graph below;

The unit is assessed to utilise its full capacity throughout the year.


90

80

70

60

50

40

30

20

10

0

Vo

lum

e flo

w (

l/s)


Volume flow: layer 0/56 (HILLSIDE DSY Vertical 11.52 Panel Only U=0.10 500ltr store .aps)

Fig 64Fig 64Fig 64Fig 64. Graph of Annual Mechanical Ventilation Flow Rates. Graph of Annual Mechanical Ventilation Flow Rates. Graph of Annual Mechanical Ventilation Flow Rates. Graph of Annual Mechanical Ventilation Flow Rates

59

C02 levels within the building have been assessed. The following results are achieved;

The following results are achieved within the Entrance Hall, in which the CO2 sensor is located;


6500

6000

5500

5000

4500

4000

3500

3000

2500

2000

1500

1000

500

0

CO

2 c

on

ce

ntr

atio

n (

pp

m)


Room CO2 concentration: 00 Lobby (HILLSIDE DSY Vertical 11.52 Panel Only U=0.10 500ltr store .aps) Room CO2 concentration: 00 Guest Ensuite (HILLSIDE DSY Vertical 11.52 Panel Only U=0.10 500ltr store .aps)

Room CO2 concentration: 00 Utility Kitchen (HILLSIDE DSY Vertical 11.52 Panel Only U=0.10 500ltr store .aps) Room CO2 concentration: 00 Study/Office (HILLSIDE DSY Vertical 11.52 Panel Only U=0.10 500ltr store .aps)

Room CO2 concentration: 00 Guest Room (HILLSIDE DSY Vertical 11.52 Panel Only U=0.10 500ltr store .aps) Room CO2 concentration: 01 Master Bedroom (HILLSIDE DSY Vertical 11.52 Panel Only U=0.10 500ltr store .aps)

Room CO2 concentration: 00 Entrance Hall (HILLSIDE DSY Vertical 11.52 Panel Only U=0.10 500ltr store .aps) Room CO2 concentration: 01 Master Ensuite (HILLSIDE DSY Vertical 11.52 Panel Only U=0.10 500ltr store .aps)

Room CO2 concentration: -01 Bedroom 3 (HILLSIDE DSY Vertical 11.52 Panel Only U=0.10 500ltr store .aps) Room CO2 concentration: -01 Bedroom 3 Ensuite (HILLSIDE DSY Vertical 11.52 Panel Only U=0.10 500ltr store .aps)

Room CO2 concentration: -01 Bedroom 4 Ensuite (HILLSIDE DSY Vertical 11.52 Panel Only U=0.10 500ltr store .aps) Room CO2 concentration: -01 Bedroom 4 (HILLSIDE DSY Vertical 11.52 Panel Only U=0.10 500ltr store .aps)

Room CO2 concentration: -01 Reception (HILLSIDE DSY Vertical 11.52 Panel Only U=0.10 500ltr store .aps) Room CO2 concentration: -01 Corridor/Stair (HILLSIDE DSY Vertical 11.52 Panel Only U=0.10 500ltr store .aps)

Room CO2 concentration: 00 Kitchen (HILLSIDE DSY Vertical 11.52 Panel Only U=0.10 500ltr store .aps) Room CO2 concentration: 00 Dining (HILLSIDE DSY Vertical 11.52 Panel Only U=0.10 500ltr store .aps)

Room CO2 concentration: 00 Main Reception (HILLSIDE DSY Vertical 11.52 Panel Only U=0.10 500ltr store .aps)


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500

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CO

2 c

on

ce

ntr

atio

n (

pp

m)


Room CO2 concentration: 00 Entrance Hall (HILLSIDE DSY Vertical 11.52 Panel Only U=0.10 500ltr store .aps)

Fig 65Fig 65Fig 65Fig 65. Graph of Annual CO2 Levels by Room. Graph of Annual CO2 Levels by Room. Graph of Annual CO2 Levels by Room. Graph of Annual CO2 Levels by Room

Fig 66Fig 66Fig 66Fig 66. Graph of Annual CO2 Levels within Entrance Hall. Graph of Annual CO2 Levels within Entrance Hall. Graph of Annual CO2 Levels within Entrance Hall. Graph of Annual CO2 Levels within Entrance Hall

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Relative humidity has been assessed within the building. The following results are achieved;

Results for both CO2 and relative humidity are tabulated below; Room Relative Humidity C02 Concentration

Percentage of occupied time >65% Relative Humidity

Percentage of occupied time >75% Relative Humidity

Percentage of occupied time >1000ppm C02 Concentration

Percentage of occupied time >1500ppm

C02 Concentration

00 Lobby 0 0 3.2 0.9 00 Guest En-suite 57.7 0 0.9 0 00 Utility Kitchen 52.752.752.752.7 26.8 31.131.131.131.1 10.410.410.410.4 00 Study/Office 25.425.425.425.4 6 8.7 3.2 00 Guest Room 0 0 1.1 0.1

01 Master Bedroom 12.4 0.8 31.231.231.231.2 2.6 00 Entrance Hall 0 0 0.8 0.0

01 Master En-suite 21.3 4.1 30.9 2.3 -01 Bedroom 3 14.6 0.3 0.6 0.1

-01 Bedroom 3 En-suite 19.9 1.6 1.3 0.0 -01 Bedroom 4 En-suite 55.8 11.1 33.4 3.9

-01 Bedroom 4 13.6 0.9 33.3 3.5 -01 Reception 37.737.737.737.7 12 15 5.4

-01 Corridor/Stair 0 0 4.2 0.2 00 Kitchen 7.2 1.5 1 0.0 00 Dining 6.7 1.2 1.3 0.0

00 Reception 6.9 1.5 1.3 0.0


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90

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40

30

20

10

Pe

rce

nta

ge

(%

)


Relative humidity: 00 Lobby (HILLSIDE DSY Vertical 11.52 Panel Only U=0.10 500ltr store .aps) Relative humidity: 00 Guest Ensuite (HILLSIDE DSY Vertical 11.52 Panel Only U=0.10 500ltr store .aps)

Relative humidity: 00 Utility Kitchen (HILLSIDE DSY Vertical 11.52 Panel Only U=0.10 500ltr store .aps) Relative humidity: 00 Study/Office (HILLSIDE DSY Vertical 11.52 Panel Only U=0.10 500ltr store .aps)

Relative humidity: 00 Guest Room (HILLSIDE DSY Vertical 11.52 Panel Only U=0.10 500ltr store .aps) Relative humidity: 01 Master Bedroom (HILLSIDE DSY Vertical 11.52 Panel Only U=0.10 500ltr store .aps)

Relative humidity: 00 Entrance Hall (HILLSIDE DSY Vertical 11.52 Panel Only U=0.10 500ltr store .aps) Relative humidity: 01 Master Ensuite (HILLSIDE DSY Vertical 11.52 Panel Only U=0.10 500ltr store .aps)

Relative humidity: -01 Bedroom 3 (HILLSIDE DSY Vertical 11.52 Panel Only U=0.10 500ltr store .aps) Relative humidity: -01 Bedroom 3 Ensuite (HILLSIDE DSY Vertical 11.52 Panel Only U=0.10 500ltr store .aps)

Relative humidity: -01 Bedroom 4 Ensuite (HILLSIDE DSY Vertical 11.52 Panel Only U=0.10 500ltr store .aps) Relative humidity: -01 Bedroom 4 (HILLSIDE DSY Vertical 11.52 Panel Only U=0.10 500ltr store .aps)

Relative humidity: -01 Reception (HILLSIDE DSY Vertical 11.52 Panel Only U=0.10 500ltr store .aps) Relative humidity: -01 Corridor/Stair (HILLSIDE DSY Vertical 11.52 Panel Only U=0.10 500ltr store .aps)

Relative humidity: 00 Kitchen (HILLSIDE DSY Vertical 11.52 Panel Only U=0.10 500ltr store .aps) Relative humidity: 00 Dining (HILLSIDE DSY Vertical 11.52 Panel Only U=0.10 500ltr store .aps)

Relative humidity: 00 Main Reception (HILLSIDE DSY Vertical 11.52 Panel Only U=0.10 500ltr store .aps)

Fig 67Fig 67Fig 67Fig 67. Graph of Annual . Graph of Annual . Graph of Annual . Graph of Annual Relative Humidity Levels by RoomRelative Humidity Levels by RoomRelative Humidity Levels by RoomRelative Humidity Levels by Room

Fig 68Fig 68Fig 68Fig 68. Table of Relative Humidity and CO2 Levels beyond Acceptable Limits. Table of Relative Humidity and CO2 Levels beyond Acceptable Limits. Table of Relative Humidity and CO2 Levels beyond Acceptable Limits. Table of Relative Humidity and CO2 Levels beyond Acceptable Limits

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Conclusions: CO2 levels are shown to peak at periods where the house is fully occupied (6 people + 3 evening guests in Reception/Dining/Kitchen), however CO2 concentrations remain acceptable. High relative humidity levels occur within occupied areas such as the office/study and utility kitchen. The specification at present accounts for humidity sensors only within the en-suites and main kitchen. It is recommended that these are extended to include other occupied areas including the office/study, utility kitchen and lower ground floor reception. Of course, the ventilation system could run at a fixed rate with manual ‘boost’ for periods of post showering/high occupancy, but this would result in higher thermal losses through the ventilation system, leading to higher heating demands.

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4.0 Study into Suitable Sizing of the Thermal Store A principal element of the thermal simulation is to establish suitable sizing of the thermal store, used as part of the active solar heating system. The design philosophy is to utilise a thermal store, located within the plant room, to provide DHW at 60°+ and to provide for space heating via a LTHW circuit at 45°C. In order to generate heat, 4Nr evacuated tube solar thermal collectors (specification TBC) shall be located on the roof of the building at a vertical inclination. These panels are optimised for winter time gains, with peak gains occurring within April and September as shown with Fig. 46. In addition, 53m² (TBC) of photovoltaic panels shall also be available for providing electrical power which can be used to operate immersion heaters located within the thermal stores. The efficiency of PV panels will be around 15-18%, compared to the solar thermal panels at around 65%. Therefore, the energy generation via PV, although significantly larger in area, is around the same as that of the solar thermal collectors. However, the PV collectors have the added benefit of exported excess energy to the national grid via a two way metre. The added benefit of utilising a large quota of PV generated energy within the heating system means that both the feed-in-tariff (FiT) and abundant local renewable generation can be made viable. In such an arrangement, the solar thermal system is design to be optimised for winter-time generation, but will continue to feed into the system annually. The PV system shall also contribute a substantial quota of energy inputs into the thermal store, but will be able to export energy to the grid during the summer months where there is limited demand. The two systems have different characteristics. The solar thermal system can efficiently produce low temperature water in volume. The immersion heaters, powered by the PV array are more ideally suited to creating high temperature water, ideal for DHW consumption. Recommendations are given in this regard at the end of this section of the report. In respect of the capacity of the thermal store specified, this is a factor of the DHW and space heating demands and the generation capacity and profile available. Higher capacity thermal stores contain a high thermal mass, which takes longer to heat and longer to cool, allowing fluctuations in demand and generation profiles to be more easily ironed out. The additional thermal capacity also allows energy inputs to be input into the store for a higher proportion of the year, since there is more capacity available. However, with additional capacity comes higher thermal losses, and lower temperatures, which may be too low for DHW use. As such, an optimum sized store is calculable based upon the demand and generation profiles. This section of the report utilises system modelling within T*Sol software, gleaning DHW and space heating demand profiles from the IES model previously described.

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4.1 Investigation into the Relationship of Thermal Store Capacity and Auxiliary Energy Inputs Based on Solar Thermal Inputs Alone

T

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