Increasing energy productivity is the result of a combination of energy efficiency policies and innovations as well as structural changes in the economy. Had U.S. energy productivity remained at the level observed in 1980, U.S. energy consumption would have been more than double its current value, to achieve the same level of our current economic growth.1 ACEEE analysis estimates that energy efficiency is responsible for approximately 60% of the energy productivity improvements.2

Similarly, the U.S. would have produced 78% higher carbon emissions, or an additional 3,810 million metric tons of carbon dioxide in 2021, without energy efficiency investments. This highlights the extraordinary scale of energy efficiency as a tool for decarbonization.Similarly, the U.S. would have produced 60% higher carbon emissions, or an additional 3,540 million metric tons of carbon dioxide in 2018, without energy efficiency investments. This highlights the extraordinary scale of energy efficiency as a tool for decarbonization.3

Utilities and other program administrators develop and implement a diverse portfolio of programs that help different customers and sectors save energy using a variety of strategies. The cost-effectiveness of different programs can be quantified through several approaches, including by dividing the expenses by the number of kilowatt-hours saved for a levelized cost of saved electricity. The levelized costs shown above include only the program administrator costs, not any additional costs paid by customers.

Lawrence Berkeley National Laboratory considered the levelized program administrator cost of saved electricity for a variety of utility ratepayer-funded efficiency program types in 2018, finding that costs ranged from residential lighting rebate programs (1.2 cents/kWh) to HVAC retrofits (8.6 cents/kWh).4

Energy efficiency has also led to enormous bill savings across the economy. Based on some simple assumptions,5 the chart shows the total energy expenditures across the U.S. economy from 1980 to 2020, and the energy cost savings each year due to energy efficiency investments since 1980. As energy prices overall dropped since 2008 (until this year), the amount of energy saved each year grew, and the dollar savings have remained around $800 billion each year.

To put this number in context: if we had had the same level of economic growth without these savings, energy spending would have been 77%, or $774 billion, higher in 2020.

Electric vehicles (EVs) in the light duty segment (which include battery electric, plug-in hybrid, and fuel cell electric vehicles) present significant efficiency gains over conventional vehicles, with battery electric cars estimated to be twice as efficient as a conventional car on a well-to-wheel basis.6 The U.S. market for these vehicles has grown quickly in the last decade, driven in part by Zero-Emission Vehicle mandates in select states, and federal and state tax credits. In the first two quarters of  2022, the annual U.S. sales of EVs have already exceeded total sales in 2015 by more than a factor of four, to 430,000, primarily due to battery electric vehicle growth. The U.S. currently has an estimated 1.5 million electric vehicles, and there are 84 different makes and models of plug-in hybrid and battery electric vehicles on the U.S. market as of September 2022.7 8

Manufacturing makes up roughly 80% of industrial emissions, while non-manufacturing subsectors of construction, mining, and agriculture make up the balance of industrial emissions.

The chart illustrates the estimated total monetary value of health benefits ($541 million) for one year of savings (also called incremental savings) from electricity ratepayer-funded energy efficiency programs implemented in 20178, 9. This amounts to 40% of the estimated levelized total cost of the incremental electricity savings from the energy efficiency programs across all regions shown ($1.36 billion).10, 11

A building performance standard (BPS) is a policy that sets energy use or GHG emissions targets for existing buildings. BPS policies can complement codes for new buildings and be adapted based on the jurisdiction. BPS policies typically set increasing targets over time, with timelines often varying based on the size of the building or based on equity considerations, such as allowing extended timelines for compliance for affordable housing (e.g., St. Louis and DC). 12

In January 2022, the federal government launched the National BPS Coalition. Over 30 participating jurisdictions are committed to passing a building performance policy by Earth Day 2024.13

The construction of zero net energy and zero energy ready buildings is a very recent trend that still constitutes a small fraction of the building market, but is growing rapidly.14 From 2017 to 2020, the total number of residential units nearly doubled. As of July 2022, the number of verified commercial buildings has reached 154 and the number of emerging commercial buildings striving for zero net energy has reached 462, respectively representing a 30% and 70% increase since 2018.15 Certifications such as LEED Zero may help drive more net zero energy projects by facilitating recognition and incentives. States and cities are also beginning to incorporate net zero energy into codes and stretch codes.16