Study 1: “Statewide and Regional Water-Energy Relationship Study”

Study 2: “Water Agency and Function Component Study and Embedded Energy-Water Load Profiles”

–

California Public Utilities Commission Embedded Energy in Water

On January 19, 2007, the CPUC opened a water-energy proceeding to consider whether/how energy “embedded in water” should be recognized as an energy efficiency resource.

Decision 12-07-050:• Authorized the IOUs to conduct water-energy pilots• Directed that three studies be conducted:

– Study 1 - Statewide and Regional Water Energy Relationship Study– Study 2 - Water Agency and Function Component Study and

Embedded Energy -Water Load Profiles– Study 3 - End-Use Water Demand Profile Study

2

–

Study 1: Intro and Purpose

Study 1: Statewide and Regional Water-Energy Relationship • Develop a predictive model of the

functional relationship between wholesale water deliveries in California and the energy used to deliver that water.

• Increase understanding of the relationship of energy and potable water systems at the wholesale level.

• Project the potential range of statewide energy impacts given a variety of future conditions.

Developing the first model to analyze and forecast energy use by wholesale water supply systems statewide

3

–

Study 1: Challenges

• Large number of systems and entities with complex relationships

• California’s water system is comprised of multiple federal, state, regional and local water agencies, joint powers authorities and special districts.

• The state’s water-energy balance is comprised of complex delivery, storage and transfer relationships among all of these entities.4

–

Study 1: Segment Focus

Energy Consuming Segments of California’s Water-Use Cycle

Source

Supply & Conveyance

Water TreatmentWater

Distribution

Wastewater Treatment

Wastewater Collection

Recycled Water Treatment

Recycled Water Distribution

End Use: Agriculture, Residential, commercial,

industrial

Source

Discharge

Focus of Study 1

“Refining Estimates of Water‐Related Energy Use in California”, Navigant Consulting for the California; Energy Commission Public Interest Energy Research division (PIER), CEC‐500‐2006‐118, 2006.

5

Systems Modeled

• Nine large or wholesale systems

• Additional supplies were added to complete the picture:– Groundwater– Local Surface Water– Recycled Water– Desalination

(Brackish and Seawater)

SWP

CVP

LAA (LADWP)

MWD

CRA

SDCWA

SCWVD

SFPUC

MID

6

–

Study 1: Model Highlights

The model is designed to be flexible and user-friendly

• Models both regional and statewide water supply and associated energy use by each wholesale water system and water supply

• Transparent, easy to understand, and easy to use – Excel based model

• Easily adjustable to evaluate a range of scenarios

• Integrates supply constraints• Monthly energy results • Projects energy use in 2020 and 2030

7

–

Study 1: Scenarios

The model will be used to analyze various future scenarios for the state water system• “Given a specific water delivery

requirements … what is the expected energy use?”

• Work plan specifies analysis of key regulatory and policy decisions inside and outside of California for example:– District Judge Wanger’s decision that required

export pumping reductions in order to protect delta smelt

– Policies promoting water conservation• The Study Team met with stakeholders to

discuss other policies to model

8

–

Study 1: Scenarios

Scenarios are designed to capture the range of future possibilities• There are too many variables and policies

to test separately for our report• Two scenarios were designed to estimate

the range of future energy impacts in 2020 and 2030– Scenario 1 – A Low-Energy Scenario that assumes low demand and a

package of policies that will reduce energy consumption– Scenario 2 – A High-Energy Scenario that assumes high demand and a

package of policies that could increase energy consumption

• These are intended to represent the range of likely outcomes to bracket the majority of other scenarios

9

–

Model’s Web Interface

10

–

Facility and Region Information

11

–

Model Input/Output:Total Energy

12

Monthly Energy Profile

13

–

Study 2: Intro and Purpose

Study 2: Water Agency and Function Component Study and Embedded Energy-Water Load Profiles• Increase understanding of the relationship

of energy and water/wastewater operations at the retail water agency/functional level.

• Determine the range of energy intensity of water operations and key drivers

• Develop 24-hour energy profiles of water and wastewater agencies

Producing the most detailed analysis to date of the range of energy intensities observed in California retail water systems

14

–

Study 2: Segment Focus

Energy Consuming Segments of California’s Water-Use Cycle

“Refining Estimates of Water‐Related Energy Use in California”, Navigant Consulting for the California; Energy Commission Public Interest Energy Research division (PIER), CEC‐500‐2006‐118, 2006.

Source

Supply & Conveyance

Water Treatment Water Distribution

Wastewater Treatment

Wastewater Collection

Recycled Water Treatment

Recycled Water Distribution

End Use: Agriculture, Residential, commercial,

industrial

Source

Discharge

Focus of Study 2

15

–

Study 2: Previous Body of Knowledge

Previous body of knowledge on the range of energy intensities is based on a few case studies. Range of Energy Intensities

(kWh/MG)

Segment or Facility Type Low HighWater Supply and Conveyance 0 14,000

Water Treatment 100 16,000Water Distribution 700 1,200

Wastewater Collection and Treatment 1,100 4,600Wastewater Discharge 0 400

Recycled Water Treatment and Distribution

400 1,200

16

–

Study 2: Previous Body of Knowledge

Previous data on 24-hour energy profiles is also based on a few case studies; data did not cover multiple facility types.

Sample Central Valley Irrigation District Power Load Shape for July 15

17

–

Study 2: Agency Selection

Study 2 selected 30 water and wastewater agencies for data collection that were deemed “representative”• These agencies collectively comprise at

least 90% of the most important types of water-energy relationships in California’s water resources

• Criteria for selection included– Types of water agencies: Urban, Agricultural, Water, Wastewater– Geographic region– Treatment technologies/requirements– Service area topology– Energy service provider

18

–

Study 2: No. California Agencies Selected

SAN JOSE WATER COMPANY

19

–

Study 2: So. California Agencies Selected

20

–

Study 2 Data issues

• Data collection from water and wastewater agencies– Resources/Time– Availability– Different formats– Agencies Unique

• Agency Profiles– System details– Results

• Water and energy metered at different time steps• Database approach: ACCESS

21

–

Data Analysis Tool: Graphical Interface

22

Summer Average Water DemandSummer High Water DemandSummer Low Water DemandWinter Average Water DemandWinter High Water DemandWinter Low Water DemandSummer Peak Energy Demand

–

Typical Load Profile

23

0

1,000

2,000

3,000

4,000

5,000

6,000

7,000

8,000

9,000

1:00

AM

2:00

AM

3:00

AM

4:00

AM

5:00

AM

6:00

AM

7:00

AM

8:00

AM

9:00

AM

10:0

0 AM

11:0

0 AM

12:0

0 PM

1:00

PM

2:00

PM

3:00

PM

4:00

PM

5:00

PM

6:00

PM

7:00

PM

8:00

PM

9:00

PM

10:0

0 PM

11:0

0 PM

12:0

0 AM

Ener

gy (k

Wh)

Distribution Pumps Raw Water Pumps

Water Treatment Plants Total System

–

Monthly Average Energy Intensity by Facility

24

–

Energy Intensity Over the Year

25

–

Status of Studies 1 and 2

• Final Draft Reports being submitted to CPUC– Includes results and recommendations

• Draft Studies to be posted on CPUC Website in mid-May• Study 1 Model and Study 2 Database Tool also available

on line • CPUC Public Workshop scheduled for May 26• Receive public comments through mid-June• Final Reports and Tools available in July

26

–

Wrap-Up

Thank you!

To stay informed log into:

http://www.energydataweb.com/cpuc/default.aspx

Subscribe to the topic: “Embedded Energy in Water Studies”

Bill BennettGEI Consultants, Inc.bbennett@geiconsultants.com(916) 631-4564

Laurie ParkNavigant Consulting Inc.LPark@navigantconsulting.com(916) 631-3274

27