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High Efficiency Unit Heaters

Workpaper PresentationPrepared for Cal TF PresentationSept 24, 2014

Overview

• Seeking TF approval of draft workpaper

• Measure Description

• Measure Summary

• Abstract Review Comments – Cal TF

• Abstract Review Comments – Commission Staff

• CEUS data: SCE vs. statewide

• EFLH: Connected vs. peak load, other considerations

• Savings: WP vs DEER

• IMC

Measure Description

• Unit Heater• Self-contained, automatically-controlled, vented fan-type

gas space heater designed to be installed without ducts, within the heated space

• Thermal Efficiency: 90% or above (11% improvement)• Size ranging 50~600 kBtuh

• Measure Application Type• ROB/NC

• Measure Delivery Type• Prescriptive rebate per kBtuh

• Impacted Market• Non-residential• Warehouses, distribution facilities, garages, loading

docks, & etc.

• Market Potential• Low shipping volume in CA

Measure Summary

• Gas Savings• 0.38 therms/kBtuh (CA average)• Range between 0.17 ~ 0.87 therm/kBtuh for 16 CZs• Decreased by a factor of 2.85 (peak load vs. connected

load)

• IMC• $8.17/kBtuh• Incremental equipment cost + additional material &

labor for condensing unit

• EUL• 20 years• DOE shipping data + DEER HVAC-Frnc

• Net-to-Gross: • 0.70 default value per DEER All-Default<=2yrs

Abstract Comments– Cal TF

EUL – 20 years

Oversizing

• No oversizing factor to be considered

Savings Methodology

• Engineering calculation using CEUS and other

resources

Building type

• Use warehouses

• Enclosed space with an appropriate temperature

control

Abstract Comments– Commission Staff

Calculating savings based on the actual capacity and climate zones.

Equivalent full load hours highest in SCE

EFLH: • Non-coincident peak heating load vs. Total

connected equipment load

Comparison to simplified DEER

Additional Installation Cost

Savings Calculation

𝑈𝑛𝑖𝑡 𝐻𝑒𝑎𝑡𝑒𝑟 𝐴𝑛𝑛𝑢𝑎𝑙𝑂𝑝𝑒𝑟𝑎𝑡𝑖𝑛𝑔𝐻𝑜𝑢𝑟𝑠(𝐸𝐹𝐿𝐻 )(𝐻𝑟𝑌𝑟 )=

𝐻𝑒𝑎𝑡𝑒𝑑 h𝑊𝑎𝑟𝑒 𝑜𝑢𝑠𝑒𝐻𝑒𝑎𝑡𝑖𝑛𝑔𝐸𝑈𝐼 ( 𝑘𝐵𝑡𝑢𝑆𝑞 .𝐹𝑡−𝑌𝑟 )

𝐶𝑜𝑛𝑛𝑒𝑐𝑡𝑒𝑑 h𝑊𝑎𝑟𝑒 𝑜𝑢𝑠𝑒𝐻𝑒𝑎𝑡𝑖𝑛𝑔 𝐿𝑜𝑎𝑑 (𝑘𝐵𝑡𝑢/𝐻𝑟𝑆𝑞 .𝐹𝑡 )

𝐵𝑎𝑠𝑒𝑙𝑖𝑛𝑒𝐶𝑜𝑛𝑠𝑢𝑚𝑝𝑡𝑖𝑜𝑛(𝑘𝐵𝑡𝑢𝑌𝑟 )=𝐴𝑣𝑒𝑟𝑎𝑔𝑒𝐻𝑒𝑎𝑡𝑒𝑟 𝐶𝑎𝑝𝑎𝑐𝑖𝑡𝑦 (𝑘𝐵𝑡𝑢𝐻𝑟 )×𝐴𝑛𝑛𝑢𝑎𝑙𝑂𝑝𝑒𝑟𝑎𝑡𝑖𝑛𝑔𝐻𝑜𝑢𝑟𝑠(𝐻𝑟𝑌𝑟 )

𝐴𝑣𝑒𝑟𝑎𝑔𝑒𝐻𝑒𝑎𝑡𝑖𝑛𝑔 𝐿𝑜𝑎𝑑(𝑘𝐵𝑡𝑢𝑌𝑟 )=𝐵𝑎𝑠𝑒𝑙𝑖𝑛𝑒𝐶𝑜𝑛𝑠𝑢𝑚𝑝𝑡𝑖𝑜𝑛 (𝑘𝐵𝑡𝑢𝑌𝑟 )×𝐵𝑎𝑠𝑒𝑙𝑖𝑛𝑒 𝐸𝑓𝑓𝑖𝑐𝑖𝑒𝑛𝑐𝑦 (80%)

h𝐻𝑖𝑔 𝐸𝑓𝑓𝑖𝑐𝑖𝑒𝑛𝑐𝑦 𝐶𝑜𝑛𝑠𝑢𝑚𝑝𝑡𝑖𝑜𝑛(𝑘𝐵𝑡𝑢𝑌𝑟 )=𝐴𝑣𝑒𝑟𝑎𝑔𝑒𝐻𝑒𝑎𝑡𝑖𝑛𝑔𝐿𝑜𝑎𝑑 (𝑘𝐵𝑡𝑢𝑌𝑟 )

h𝐻𝑖𝑔 𝐸𝑓𝑓𝑖𝑐𝑖𝑒𝑛𝑐𝑦 (90%)

𝐺𝑎𝑠𝑆𝑎𝑣𝑖𝑛𝑔𝑠 ( h𝑇 𝑒𝑟𝑚h𝑘𝐵𝑡𝑢 )=

𝐵𝑎𝑠𝑒𝑙𝑖𝑛𝑒𝐶𝑜𝑛𝑠𝑢𝑚𝑝𝑡𝑖𝑜𝑛(𝑘𝐵𝑡𝑢𝑌𝑟 )− h𝐻𝑖𝑔 𝐸𝑓𝑓𝑖𝑐𝑖𝑒𝑛𝑐𝑦𝐶𝑜𝑛𝑠𝑢𝑚𝑝𝑡𝑖𝑜𝑛(𝑘𝐵𝑡𝑢𝑌𝑟 )𝐴𝑣𝑒𝑟𝑎𝑔𝑒𝐻𝑒𝑎𝑡𝑒𝑟 𝐶𝑎𝑝𝑎𝑐𝑖𝑡𝑦 ( h𝑘𝐵𝑡𝑢 )×100 ( 𝑘𝐵𝑡𝑢

h𝑇 𝑒𝑟𝑚 )

CEUS:SCE vs. Statewide

• Utilities Areas in CEUS

• SCE: Substantially higher consumption (W/H)• SCE: Lower than PG&E (20%) for other building types• Study Sample

• 250 warehouses surveyed • 65 sites metered

• TF Feedback Requested: Use statewide data?

CEUS: Equivalent Full Load HourPeak Load vs. Connected Load

• Peak Load• Calibrated using metered data collected by fan

measurements for sample of buildings• One-hour maximum consumption, based on

simulated load profile

• Connected Load• Gathered from actual site surveys of equipment

inventories • Represents how equipment is actually sized and

placed for this building type

Equivalent Full Load Hour:Additional Considerations

• Operation depends on • Thermostat settings and setback schedules• Bldg. location and climate• Door openings• Ventilation system• Ceiling heights• Internal heating loads

• Agreed on “Connected Load”?

Comparison with Simplified DEER

• Preliminary analysis using DEER by Commission Staff

• Conditioned Storage (SCn)

• D08-NE-HVAC-airAC-SpltPkg-240to759kBtuh-9p8eer

• Measure Case: HEATING-HIR = 1.11 

• Base Case: HEATING-HIR = 1.25

• Are savings reasonable?

Consideration of Cost

• Additional labor and supporting material• Site-specific conditions dictating whether installation

cost is higher or lower than conventional unit heaters.• Condensate disposal• Replacement of existing flue• Condensate neutralizers, and outdoor-air dampers

require periodic servicing• Estimated additional $500 incremental installation

cost per unit• IMC: $6.07 (equipment) + $2.10 (installation) = $8.17

/ kBtuh

Question or Comment?