States, utilities, and non-governmental organizations across the country have commissioned analyses over the years to identify potential energy savings (typically for electricity) available within their jurisdictions. These studies can be used to fulfill a variety of needs, including energy efficiency program planning, state goal setting, utility resource planning, and other priorities.

This page showcases a compilation of state and local energy efficiency potential studies published since 2010 to serve as a resource for energy planners and as a baseline for future analyses. Although these studies have been completed by a variety of authors to meet numerous purposes and have important differences among them, the majority show an average annual energy efficiency potential savings rate¹ in the range of 1 to 1.5% electricity savings per year over a period of 10–20 years (see middle and bottom charts in below figure). The top chart in the below figure shows that many utilities have achieved robust savings, in some cases outperforming the identified achievable potential and suggesting the potential for even greater savings. Collectively, the potential electricity savings identified in these studies demonstrate that a high level of energy efficiency potential is available throughout the United States.

^{1_{The average annual energy efficiency potential savings rate was calculated based upon the total electricity savings percentage in the final year of the study relative to the study’s baseline forecasted sales, divided by the number of years included in the study. If the average annual energy efficiency potential savings rate was reported in the publication, that value was used in the figure. Only the economic potential is shown in the figure for studies that reported both economic and achievable potential. Utility performance data is from the 2020 American Council for an Energy-Efficient Economy’s Utility Energy Efficiency Scorecard (2018 data).}}

On This Page

• Introduction to Energy Efficiency Potential
• Important Differences Across Studies
• Energy Efficiency Potential Studies Catalog
• Submit Additional Studies

Energy efficiency reduces demand-side electricity and natural gas consumption. Energy efficiency programs can lower consumer utility costs and serve as an alternative to increased energy production. Energy efficiency potential is an estimate of how much energy efficiency is available in a utility footprint, state, or region under a given set of parameters.

There are four generalized categories of energy efficiency potential, each quantified differently. Technical potential is the total energy that could be saved by efficiency measures, without consideration of cost or willingness of users to adopt the measures. Economic potential is the subset of technical potential that is considered cost-effective compared to a supply-side energy resource alternative (i.e., energy generation). Achievable potential, a subset of economic potential, is the energy savings that could be realistically achieved given real-world constraints, including market and programmatic barriers. Some studies quantify the program potential that an individual energy efficiency measure (often a proposed utility program) could attain. Individual studies may have slight variations on these generalized categories.

There are many resources available to help energy planners conduct energy efficiency potential studies:

• DOE's Energy Efficiency Savings Opportunities and Benefits
• DOE's SEE Action Guides for States
• EPA's National Action Plan for Energy Efficiency
• National Energy Screening Project's National Standard Practice Manual for Benefit-Cost Analysis of Distributed Energy Resources 

National analyses and trends in energy efficiency potential can be found in these resources:

• DOE's U.S. Energy Efficiency Potential Maps
• Electric Power Research Institute’s U.S. Energy Efficiency Potential Through 2040: Summary Report 

The studies compiled below represent publicly available energy efficiency potential studies undertaken since 2010², but do not represent a reconciled set of analyses. With a variety of sponsoring organizations and consultants undertaking these efforts and a range of ways in which these studies are used, assumptions, methodologies, and coverage also differ.

Studies consider the energy efficiency potential of different sectors within their footprint. The figure below demonstrates the inclusion of different sectors for many of the studies included in this catalog. Most studies included energy efficiency potential in the residential, commercial, and industrial sectors. Some studies further specify savings from agriculture, street lighting, and other sectors. Additional cost-effective savings may be available with expanded sectoral coverage.

Highlighted below are other differences among the studies, which make comparisons across studies inappropriate for most purposes:

• Reported potential: While some studies analyze and report economic potential, others only report achievable potential. Policy-related energy efficiency projections are included in the catalog as achievable potential studies.
• Baseline year and study length: Studies were conducted between 2007 and 2018. The baseline year used to calculate savings potential for each study varies, as does the number of years over which savings are assumed to accumulate. These differences will have an impact on the results.
• Projection methods: Different models are used to forecast savings over time. While some models evaluate savings from individual technologies and assess cost-effectiveness on a yearly basis, others look at average potential savings across a sector or estimate savings based on similar studies. The explicit inclusion of naturally occurring savings also differs between studies.
• Avoided energy costs: The source of avoided energy costs against which efficiency measures are compared for determining cost-effectiveness differs between studies, as do the projections of those costs.
• Cost-effectiveness tests: The type of cost-effectiveness test used to screen energy efficiency opportunities differs by study, as does the application of those tests (e.g. inclusion of non-energy benefits).
• Technologies: The range of technologies included and treatment of future emerging technologies over the time period of analysis differ across the studies.
• Coverage area: Some estimates are for an entire state while others only represent a given utility’s service area.
• Annual potential savings rate: A few potential studies report an annual savings percentage (as a proportion of electricity sales) for the study period; however, many do not provide this information. To provide an illustrative common metric across studies in the catalog, the summary table below provides a calculated annual potential savings rate or the rate that was reported directly in publication. The annual savings rate was calculated based upon the percentage of the total savings in the final year of the study relative to the study’s baseline forecasted sales, divided by the number of years included in the study.

²_{Where multiple studies have been published for a given region since 2010, only the most recent report is included.}

The table below provides a high-level summary of over 100 energy efficiency potential studies conducted by state, local, and non-governmental organizations (unaffiliated with DOE) between 2010 and 2020. Details of individual studies presented here should be confirmed by reading the study.

DOE is providing links to the following studies through this online catalog but has not funded, reviewed, nor endorsed any of the methods or conclusions. All questions should be directed to the appropriate author of the published study of interest. If studies are missing or summary information is inaccurate, please contact us.

(Updated December 10, 2020)

³_{Gigawatt-hours (GWh). Where savings were not reported directly, savings were calculated either using applicable reported percentages or converting from average megawatt (aMW).}
⁴_{Average annual savings rate was calculated by dividing the total cumulative savings percentage over the period of study by the number of years in the study; the initial year of study was assumed to be the baseline.}
⁵_{Sectors include: residential (R), commercial (C), industrial (I), irrigation (Ir), agriculture (Ag), mining (Min), street lighting where specifically called out as a sector (StL), military (Mil), water/wastewater (W), government (G), distribution (D) and behavior (B), retrocommissioning and operational (BRO) as indicated.}

This catalog is intended to be a living repository of published publicly available energy efficiency potential studies.

To submit additional studies or update values included in the summary above, please email EERE.Analysis@ee.doe.gov.