Conclusions of Law
1. It would be unfair to ask customers in one energy service territory to pay for a program that largely benefits customers elsewhere.
2. For now, the Energy Division and the energy utilities should use a given water agency's average energy intensity for the purposes of ex ante evaluation.
3. The utilities shall not count embedded energy savings created during the pilot programs towards their goals.
4. We should reduce the size of SCE's toilet program, from $728,700 to $200,000 (which allows for approximately 550 direct toilet installs), and limit it to multi-family low-income installations to complement changes we are making in the PG&E toilet program (limiting PG&E to single-family installations). We should also change the EM&V study associated with this program to more accurately develop the data we need in order to determine if such a program is likely to be cost effective.
5. The funding of PG&E's toilet program should be commensurate with the multi-family high-efficiency toilet program of SCE and limited to single-family installations.
6. The Commission should direct PG&E to include pump efficiency improvements and water and wastewater treatment options in the evaluation of emerging technologies.
7. We should direct SCE to expand its leak detection proposal from a paper EM&V study to include a pilot program in its service area, and increase the proposed budget by 50% (to $300,000) to fund these added activities. In addition to the paper study, the commission expects that the program portion will include real applications of leak detection such as detecting and fixing leaks within a water system where costs and water and energy savings are quantified.
8. We should approve two embedded energy foundational studies to address the added information required to perform cost-effectiveness calculations:
1. A Statewide/Regional Water-Energy Relationship Study designed to establish the relationship between annual climate and hydrology variation, regional and statewide water demand variations and statewide energy use by the water system; and
2. A Water Agency/Function Component Study which includes a redefined Load Profile Study designed to establish detailed annual and daily profiles for energy use as a function of water delivery requirements for a full range of local, regional, state and federal water agencies within the California water system.
9. Since the studies approved herein are part of the overall evaluation work and will provide a significant fraction of the basis for energy savings estimates, the Energy Division should manage them.
10. We should approve a modest ($50,000) study of the recycled water pilot program with the intent of finding out (1) how successful the program was in convincing customers to shift water supplies, (2) how much water was shifted from fresh to recycled water, and (3) how much energy was saved by shifting from fresh to recycled water.
11. We should direct the utilities to fund and the Energy Division to manage a statewide and regional water-energy use relationship study, described in this decision, in order to obtain necessary information in this area from an unbiased, independent source.
12. We should direct the utilities to fund and Energy Division to manage the water agency functional component study described in this decision.
13. The Commission should modify the utilities' program offerings to ensure greater diversity in terms of customer classes involved, and programs tested.
14. The Commission should approve the modified programs.
IT IS ORDERED that:
1. The Commission is dedicated to allowing utilities to incorporate water conservation strategies in their energy efficiency programs to the extent that the cost-effectiveness of these strategies can be accurately measured.
2. The Pacific Gas and Electric Company (PG&E), the San Diego Gas & Electric Company (SDG&E), the Southern California Edison Company (SCE), and the Southern California Gas Company (SoCalGas) (collectively, "the energy utilities") shall implement one-year pilot programs commencing July 1, 2008, or sooner if the Energy Division determines that it is feasible to do so, to conserve water and improve the efficiency of water use, and provide funds for evaluations and studies as approved in this order and set forth in the following table:
Table 7
3. In the period running from January 1, 2008 to July 1, 2008, the energy utilities and Energy Division shall retain consultants and work together to refine pilot program details. In addition, during this period, the Energy Division and its consultants shall begin collecting baseline data needed for a meaningful "before and after" assessment of the pilot programs.
4. The Executive Director may hire and manage one or more contractors to assist the Energy Division staff in conducting the evaluations of the pilot programs and the studies described in this decision. Such costs shall be paid from funds authorized in this decision as shown in Table 8 (Ordering Paragraph 5) below. The Executive Director, with the approval of the Commission's General Counsel, (1) may contract directly with outside consultants for these services, or (2) may arrange for one or more of the utilities to contract with outside consultants for the provision of the required services to the Energy Division. Contracting through the utilities for services for Energy Division shall be subject to the agreement on terms, conditions and documentation for the contract arrangement that are acceptable to the utility and the Executive Director. However, the Energy Division will be Contract Manager and will retain all contract management responsibilities for these contracts, with the utilities funding the contract utilizing their authorized energy efficiency program funds as described above.
5. The energy utilities shall contribute the following amounts to support the pilot programs, evaluations and studies, from the utilities' unspent energy efficiency funds from prior years:
Table 8
6. In order to ensure that the Commission, the energy utilities, and participating water agencies develop the information necessary to judge the cost-effectiveness of water conservation programs that might later be included in energy utility energy efficiency portfolios, the Energy Division shall administer the approved evaluations and studies.
7. The energy utilities shall perform any necessary process evaluations (assessments of the effectiveness of program design and implementation), and utilize a portion of approved program funding for this purpose.
8. Proposed pilot programs, evaluations and studies not expressly approved in this order are denied.
9. The consolidated proceedings are closed.
This order is effective today.
Dated December 20, 2007, at San Francisco, California.
MICHAEL R. PEEVEY
President
DIAN M. GRUENEICH
JOHN A. BOHN
RACHELLE B. CHONG
TIMOTHY ALAN SIMON
Commissioners
Appendix A
QUESTIONS THE WATER-ENERGY PILOT PROPOSES TO ANSWER
Overview
The pilots proposed by the utilities would be designed to explore the potential for a water embedded energy savings program by examining, in sequence, the: 1) technical potential; 2) economic potential; and 3) programmatic potential for carrying out an effective water embedded energy savings strategy.
· Technical potential refers to the expected ability of various measures to achieve water-embedded energy savings and to the ability to evaluate and attribute the energy and cost savings from measures. In other words, technical potential involves what measures work, to what extent, and if and how they can be measured.
· Economic potential refers to the expected ability of various measures to achieve cost-effective savings as defined by various cost tests (to determine which measures are cost-effective).
· Programmatic potential refers to the expected ability of measures to be effectively delivered as a utility program. In other words, can the cost-effective measures be successfully implemented in the given time frame?
The pilots would provide resources to support both on-the-ground implementation of water conservation measures and a Water-Energy Study (study) that will be overseen by a Blue Ribbon Panel (composition to be determined). For the study, the study design would ultimately be approved by the Blue Ribbon Panel, but the study is expected to run concurrently with the on-the-ground implementation to examine multiple issues using multiple inputs, including data available from natural fluctuations in water use and data from the pilot implementation. Issues included in the study would include evaluating the on-the-ground implementation programs implemented as part of the pilot, analyzing existing data, examine methods for quantifying energy and water relationships, survey the existing body of research on the topic, etc. The study would develop information and methodologies to be used in broad rollout statewide of a program to deliver energy savings.
Together, these two elements of the pilots (on-the-ground implementation and the study) would provide answers to a set of questions listed below. The utilities noted that because this is a pilot exploring new ground, they do not know what information they would encounter and cannot guarantee that they would answer the questions, even though both the study and the on-the-ground implementation would be designed to obtain the data needed to do so.
Technical potential
Measures
1) Which measures or bundle of measures have the technical ability to be deployed effectively at a programmatic level (e.g. which measures are commercially available and viable)?
How pilot would answer: Screening of available measures by third party contractor for technical feasibility, as part of the study. All measures deployed in pilot would be evaluated for effectiveness (or a subset of the measures, if it is determined that it is not cost-effective to evaluate all measures independently and the evaluations of some measures could be generalized to others).
2) How can the additional water-embedded energy savings be calculated for existing energy programs that already save on-site water?
How pilot would answer: The study would develop a methodology for calculating energy savings for representative sample of existing programs. The methodology would be applied to the on-the-ground measures and developed with the intent for use in a statewide program rollout of water-embedded energy.
3) What emerging (water-saving) technologies (including existing technologies used in different ways and truly new technologies) might be effective in the near term and in which sectors could they be deployed?
How pilot would answer: Screening of available technology as part of the WES.
Verification and Attribution
4) What methods are available for quantifying the amount and the value of water-embedded savings? What are the costs and validity (level of accuracy) of these methods? Are the methods at the project, program, or water utility subarea level? How can such methods be developed, improved or refined to provide greater resolution?
How pilot would answer: As part of the study, existing methods would be identified, or new methods developed, based on available information regarding energy costs related to pumping, transporting, storing and treating water and wastewater. The new methods would be applied to the on-the-ground implementation of measures.
5) What is required to create "DEER-equivalent" data for measures designed to save water-embedded energy (e.g., the water and/or energy data about the incremental savings, incremental costs, measure life, etc.) be developed? What is required to create guidance, rules, and or protocols on determining the embedded energy?
How pilot would answer: Analyzed in the study. If there were sufficient resources and time, the study would develop the data and guidance.
6) What is the average energy intensity for participating customers that incorporates both the upstream and downstream water-embedded energy at the most specific level of measurement available (e.g., pressure zone upstream and wastewater treatment facility downstream)?
How pilot would answer: The study would analyze historical energy data from water utilities (SCADA or other source) to develop the average energy embedded in water. A pressure zone can be large or small depending on geography (e.g. several customers if the terrain is hilly or an entire city if the terrain is flat). If an area does not have such data, the study could develop baseline energy intensity.
7) What is the marginal energy associated with water use fluctuations related to customer's participation in on-the-ground implementation of water measures (e.g., changes in water volume (water savings) in their pressure zone and wastewater treatment facility)?
How pilot would answer: The study would analyze historical data from water utilities (SCADA or other source) on the marginal energy associated with participation in on-the-ground measures.
8) What are the time-dependent water savings impacts (load shapes)? What are the time-dependent energy impacts (load shapes)? What are the major characteristics of the operations of water agencies that affect the latter?
How the pilot would answer: Data provided by water utilities and analyzed in the study.
9) Are there natural gas embedded energy savings impacts? Can they be measured?
How the pilot would answer: The study would analyze data provided by water and gas utilities, and will look at impacts both in and out of the gas utilities service territory to determine if there is savings potential, especially given that the CEC report did not examine gas impacts.
10) What is the total water-embedded energy saved by measures? What is the impact at the local level and statewide? What methodologies can be developed to calculate and/or attribute those energy savings to utilities and other energy providers?
How the pilot would answer: Included in the study.
Economic Potential
1) What is the cost-effectiveness of counting the embedded energy: 1) in the utility service territory; 2) saved across all utility territories, and 3) of the entire statewide water cycle?
How the pilot would answer: The study would explore how the cost-effectiveness changes under different scenarios, as well as various policy options for attributing costs and savings (e.g. can policies be developed to allow non-utility energy providers to pay for their portion of the energy saved by a program implemented by a utility-water agency partnership?).
2) What are the water load and energy use profiles for the pressure zone and wastewater treatment facility or facilities associated with expected pilot program customers or groups of customers?
How pilot would answer: The study would develop with data to be provided by water utilities.
3) What is the average utility energy embedded in average water used by specific customers who might be likely to participate in a statewide program?
How pilot would answer: The study would analyze historical data from water utilities (SCADA or other source) to determine the average embedded energy for customers (this creates a baseline to which the data from question 4 can be compared). The average would be determined by developing estimates for the water-embedded energy for each stage in the water life-cycle, multiplying those estimates by the average amount of that energy provided by the utility (vs. other energy provider), and then adding the utility energy for each stage of the life-cycle.
4) What is the variability of utility energy embedded in water (as compared to average utility embedded energy) used by specific customers?
How pilot would answer: The study would analyze data from water utilities (SCADA and other) to determine what fluctuations exist, if any, such as seasonal variability, or differences due to pressure zone, time of day, or water-year type (e.g. dry versus wet). If the variability is small, it is likely that average utility embedded energy figures could be used to calculate accurate energy savings from water conservation measures. If the variability is large, such calculations may need factors that account for the variability.
5) What is the estimated market potential, by customer type, sub-sector and end use, for a statewide program designed to capture water embedded energy? With what precision can this potential be determined? What additional information, if any, is needed to improve the precision of the potential estimate?
How pilot would answer: Economic assessment developed as part of the study will identify which customer types have the highest embedded energy and segment them by geographic information.
6) Based on analysis of the technical and economic potential, which measures or bundles of measures, by technology and end use, should be considered for development into large-scale utility programs? Which should no longer be considered?
How pilot would answer: The utilities would conduct preliminary assessments to determine the customers and measures to include in the on-the-ground implementation portion of the pilot. The study would incorporate the results of the on-the-ground programs but will evaluate a wide variety of measures beyond just those implemented during the pilot phase.
7) Are the measures cost-effective? How do they compare to traditional energy efficiency measures? Do the measures produce additional benefits not captured by traditional energy efficiency measures and cost-effectiveness calculations?
How pilot would answer: The study would calculate and analyze the cost-effectiveness.
Programmatic Potential
1) Which measures or bundles of measures can be delivered by a utility program? Which of these are cost effective?
How pilot would answer: The study would evaluate the potential to actually deliver measures found to have economic potential (e.g. programmatic potential entails whether sufficient numbers of customers are interested in the measures, whether they are available, whether utilities can deliver them, etc.). The WES will evaluate both on-the-ground implementation outcomes as well as measures not implemented during the pilot phase.
2) What is the estimated programmatic potential for the program, by end use and by market subsector? How much savings can be expected over time, and at what cost?
How pilot would answer: The study would use the information from the above question to determine whether there are sufficient cost-effective measures with technical, economic, and programmatic potential to put together a successful large-scale program. The study would identify both the energy and water savings that could be expected over time from such a program.
3) What are the pros and cons of various delivery channels (e.g. rebates vs. direct install)? What are potential "lessons learned"? Are there situations in which one delivery channel is preferable? Why? Should staffing (number of staff, capabilities) be included in the assessment?
How the pilot would answer: The study would evaluate the effectiveness of the on-the-ground implementation programs in the service areas of the water partners in addition to other studies that have been done. The evaluation would be both quantitative (examining results of different channels) and qualitative (interpreting results to lessons learned).
4) What program elements should be "statewide" vs. "local"? How will successful marketing approaches differ? What generalizations can be made on the trade-offs between local variation and state-wide consistency? How the pilot would answer: Through observations of the effectiveness of the pilots in the service areas of the water partners. Assessments included in the study.
(END OF APPENDIX A)
Appendix B
Additional Studies Approved in This Decision
First Study: Statewide and Regional Water-Energy Relationship
Purpose - Provide a better understanding of how energy is used in the California water industry.
Problem Statement - While researchers have documented the on-peak energy demand attributable to the water industry in California,26 no comparable documentation exists for the annual energy use by the water sector. Precipitation in California over the last several decades has ranged from drought to floods. The precipitation experienced at geographical locations across the state also varies widely during a single year. In response to these varying year-to-year and location-to-location demand profiles, the water delivery and energy use patterns of water agencies has also varied. However, the relationship between water deliveries and energy use as influenced by changing precipitation patterns is not well understood. Field measurements of water deliveries and water delivery related energy demand and consumption can provide detailed information for specific local conditions across the state. To understand how those specific local observations will vary based upon statewide conditions requires the development of a statewide water-energy model which examines how interagency water deliveries will vary based upon statewide conditions.
The parties have actively debated whether conveyance energy (e.g., Colorado River or State Water Project) should be included in the embedded water energy in Southern California. Through this study, we intend to address that issue.
Goal of the Study - Develop a model of the functional relationship between water use in California and energy used in the water sector that can be used in a predictive mode: Given a specific water delivery requirements developed from precipitation pattern information, what is the expected energy use.
Data Requirements - Historic water availability, water deliveries and use, historic energy use in the water sector, other relevant variables (climate, population, energy costs).
TASKS:
I. Data Development
California Water Use and Deliveries
Statewide: Determine agricultural and urban sectors water deliveries annually from 1980-2005.
By utility service area: Determine agricultural and urban sectors water deliveries annually from 1980-2005.
For the State Water project: Determine water deliveries annually from 1980-2005.
For the Federal Water project: Determine water deliveries annually from 1980-2005.
For the Colorado River Project: Determine water deliveries annually from 1980-2005.
California Water Related Energy Use (kWh and MMBTU)
Statewide: For the agricultural and urban sectors annually from 1980-2005
By utility service area: Determine the agricultural and urban sectors energy use annually from 1980-2005.
For the State Water Project: Determine annual energy use from 1980-2005. Note - net energy use (consumption minus generation) is the relevant indicator here.
For the Federal Water project: Determine annual energy use from 1980-2005.
For the Colorado River Project: Determine annual energy use from 1980-2005.
Independent Variables Data: Compile information on variables that are relevant to water use and energy consumption in the water area. These will include weather (evapotranspiration and heating and cooling degree days, precipitation, etc.), population, energy costs, and others. Develop this information statewide, by utility service area, and for the state, federal, and Colorado River projects.
For the State, Federal, and Colorado River projects, also include water available, entitlements, requests for water, and actually delivered water. For the State project include all Table A, Article 21, and Article 55 water requests and deliveries.
II. Model Development
Use collected data to develop a model(s) of the functional relationship between water use in California and energy used in the water sector. The analysis should provide model characterizations by indicative sector: Statewide, utility service area, the State Water Project, and the Federal Water Project. Embedded energy (kWh/acre-ft, MMBTU/acre-ft) is the model expected output.
III. Report
Complete a technical report that summarizes the results of the research and technical finding during this project. The report should include historic relationships between water deliveries and energy use, and times series embedded energy values (kWh/acre foot or MMBTU/acre foot) for a range of scenarios of future conditions. The details of the model development, the methods used by the model for analysis and predictions as well as the model itself in electronic form shall be provided as part of the report.
For the State and Federal project, also assess the impact of United States. District Judge Wagner's27 current injunction against reduced pumping or increased water releases from late December through June.
For the State, Federal, and Colorado River projects, provide a response to the question: If water conservation results in reduced demand for water in the service area, will that be reflected in reduced water deliveries by the project, and reduced conveyance energy consumption?
Data Sources:
Water - Department of Water Resources - DWR maintains a data base on irrigated acreage and urban water use by data type, water year, and study area, for all of California. Urban water use is by customer class, source of supply, indoor/outdoor split, and population. All this water use data is available statewide, by hydrologic region, by planning area, by detailed analysis unit, or by county.
Energy - California Energy Commission (CEC) Demand Forecast and Utility Industrial Reporting. Energy consumption is available by industrial code (SIC 4941 - water supply, 4971 irrigation, 4952 Sewerage or NAICS 221310 - water supply, irrigation 221320 - sewerage).
Estimated Time of Completion: One year from start of project.
Second Study: Individual Water Agency and Functional Component Embedded Energy/Water Energy Load Profiles
Overview - This study is composed of two components: (1) a determination of individual water agency embedded energy determination by functional components and (2) a determination of water energy load profiles. The reason these two are combined in one study is that both utilize the same basic water and energy data, and combining them in one study will eliminate a duplication of effort in data gathering.
I. Embedded Energy Determination
Purpose - Develop representative range of energy intensities for water agencies in California, and representative ranges of energy intensities for the various functional components of the water system in California.
Problem Statement - Anecdotal evidence suggests that there is a huge range of energy in water deliveries in California - from an irrigation district that supplies agricultural water with very low embedded energy to an urban water agency with significant topography relying primarily upon groundwater high water treatment costs for both fresh water and wastewater. While there have been recent limited attempts to determine the energy intensity of water agencies in California28, there has been no systematic evaluation in this area. This information is critical for determining the cost effectiveness of utility water savings programs. The cost effectiveness calculations can be used to focus utility water-energy programs into areas that will have the highest energy savings.
Goal of the Proposal - Determine the range of energy intensities in water sector in California.
Data Used - Individual water agency historic water deliveries and use, individual water agency historic energy use.
Tasks:
I. Data Development
1. Selection - Representative water agencies will be selected for analysis after consultation with water trade groups in California. High, average, and low energy intensity water agencies from the four major types of water agencies in California: Wholesalers, retailers, wastewater, and irrigation districts, will be selected. Sufficient water agencies in each category should be analyzed in order to be statically representative of the class.
2. Water Agency Historic Water Supplied - For each water agency selected, water deliveries for an appropriate number of representative days per year will be obtained from the representative water agencies. Typically seven days is the minimal requirement: winter high water demand, winter average water demand, winter low water demand, summer high water demand, summer average water demand, summer low water demand, and summer demand during utility peak energy demand day.
3. Energy Use (kWh and MMBTU) - For the representative water days per year, energy consumption (both kWh and MMBTU) for every account for the selected water agencies will be collected from the utilities supplying the energy, or water agency energy billing records. Each water agency utility account should be assigned to a functional component of the water system (water supply, freshwater treatment, distribution system, administration, and wastewater treatment).
II. Embedded Energy Determination
I. Water Agency and Functional Component Embedded Energy Determination - The collected data should be used to develop the embedded energy in water (kWh/af or MMBTU/af) for both the system and functional components for the seven water type days: Water supply, freshwater treatment, distribution, administration, wastewater treatment, integrated system.
In addition, for each water type day, the marginal water source should be determined after consultation with the water agency, and the embedded energy of that water source provided. A sample summary table is shown below.
2. Utility range of Embedded Energy - The data from the individual water agencies will aggregated by utility service area to develop expected range of embedded energy by utility. Sample table shown below.
III. Report
Complete a technical report that summarizes the results of the research and technical findings during this project.
Data Sources:
Water - Individual water agencies
Energy - Utility consumption data, individual water agencies
At a minimum, the three major water agency trade groups in California will be consulted.
ACWA Association of California Water Agencies - represents public water agencies in California
CASA California Association of Sanitation Districts - represents wastewater agencies in California
CWA California Water Association - represents private water suppliers in California
Each group should be asked to categorize their members as likely to be high, average, or low energy users. Representatives from each category and the four major types of water agencies (wholesale, retail, wastewater, and irrigation districts) should be selected.
Estimated Budget: $500,000
Estimated Time of Completion: Eighteen months from start of project to final report.
II. Water Energy Load Profile Determination
Purpose - Develop representative range of water energy load profiles for water agencies in California, and representative ranges of energy load profiles for the various functional components of the water system in California.
Problem Statement - Water agency energy usage varies significantly throughout the day, and by season. Energy costs also vary significantly throughout the day and by season. The development of water energy load profiles is necessary to determine when energy associated with water is likely to be saved, and the resultant time-of-day of energy savings. The water-energy load profile can be used to determine the timing of water related energy savings, and to determine the peak demand impact of water savings programs. This type of information is critical for determining the cost effectiveness of utility water savings programs.
Goal of the Proposal - Determine shape of energy load profiles in water sector in California.
Data Used - Individual water agency historic water deliveries and use, individual water agency historic energy use, historic profile of water agency energy use.
Tasks:
I. Energy Load Profile Development
1. Energy Use Profile (kWh and MMBTU by hour) - Using the representative water agencies and their data developed in the embedded energy analysis, load profiles (kW/hr and MMBTU/hr for a 24-hour period) will be developed for the water functional components: Water supply, freshwater treatment, distribution, administration, wastewater treatment, integrated system. These profiles will be developed for an appropriate number of representative days per year. Typically seven days is the minimal requirement: winter high water demand, winter average water demand, winter low water demand, summer high water demand, summer average water demand, summer low water demand, and summer demand during utility peak energy demand day. A sample data table follows.
II. Complete a technical report that summarizes the results of the research and technical finding during this project.
Data Sources:
Water - Individual water agencies
Energy - utility consumption data, individual water agencies
Energy Load Profile Shapes - utility data (may need to use representative tariff group shapes for non time-of-use energy data), CEC demand forecast.
Estimated Budget: $300,000
Estimated Time of Completion: One year from start of the project to final
report.
Additional Studies Summary and Adoption
Statewide/Regional Water-Energy Relationship - Despite extensive discussion at workshops and in the proposals, there were no parties that proposed a study to evaluate energy use in the California water system. Since this is a vitally important area, and one which will have a direct impact on whether embedded energy in water programs should be included in the overall energy efficiency portfolio, we direct the utilities to fund and the Energy Division to manage a statewide and regional water-energy use relationship study in order to obtain necessary information in this area from an unbiased, independent source.
Water Agency /Function Component - There was extensive discussion at the workshops on the need for reliable water and energy load shapes. Therefore, the Commission adopts an additional study to address this issue. Information on the range of embedded energy in water throughout the state (and identification of areas where programs are likely to have the highest impact) is needed to determine if, and under what circumstances future embedded energy programs are likely to be cost-effective.
The water agency/function component study should determine the likely range of embedded energy in water throughout the state and should provide water energy load profile shapes that would be used in the geographic specific cost-effectiveness determinations. We, therefore, direct the utilities to fund and Energy Division to manage the water agency functional component study described in the section above.
(END OF APPENDIX B)
26 "Water Supply Related Electricity Demand in California," Demand Response Research Center/California Energy Commission, Lawrence Berkeley National Laboratory, LBNL-62041, December 2006.
27 2007 NORDC v. Kempthorne, U.S. District court for the Eastern District of California, Case Number 1:05-cv-1207 OWW.
28 "Supply and Demand Side Water-Energy Efficiency Opportunities." Final Report. Prepared for PG&E by Green Buildings Studio, February 2007.
