California has some of the most comprehensive and ambitious clean energy policies in the world.  Senate Bill 100[1] commits California to get 100 percent of its electricity from clean sources by 2045. James Temple of the MIT Technology Review calls this bill “one of the world’s most aggressive clean energy policies,” and Danny Cullenward, an energy economist and lawyer at Carnegie Institution for Science describes the bill as “the most important climate law in U.S. History.”[2]

California has made remarkable progress in growing clean energy’s share of electricity generation and has adopted aggressive greenhouse gas emission reduction targets. Yet, most buildings remain reliant on fossil fuels, especially for space and water heating. Installing heat pump technologies will be instrumental to meeting California’s decarbonization goals as they offer a low- or no-carbon pathway for meeting critical building functions (for example, water and space heating) that have traditionally been achieved through appliances known to emit greenhouse gasses.

Opinion Dynamics developed a market baseline and market characterization of the California heat pump market including air source heating and cooling heat pumps, ground source heating and cooling heat pumps, heat pump water heaters, heat pump pool heaters, and heat pump clothes dryers. We took a comprehensive approach to studying the market and explored the barriers to heat pump deployment in a variety of residential settings including single-family homes, multifamily buildings, market-rate homes, and affordable housing. We also examined how the feasibility of heat pump installations in these building types can vary between retrofit and new construction scenarios.

We collected important primary data for this study on air source heat pumps and heat pump water heater costs that can be used to update and bolster adoption models. Finally, in this study, we gathered best practices from program staff in other jurisdictions with mature heat pump programs. The baseline measurements for key metrics developed by this study will serve as a point of comparison to measure market impacts from heat pump programs over time and provide key information to guide heat pump program design and implementation strategies.

A key challenge with this study was recruiting busy trade allies to spend up to an hour on the phone with our interview staff or a couple of hours in the Delphi panel. We met the study goals by reacting to this challenge nimbly and adapting our recruitment approaches. First, we paused contacting HVAC contractors during a heat wave and wildfires that made them busier than usual and resumed at an appropriate time. Second, we leveraged contacts’ networks and used snowball sampling to reach additional contacts. Third, we offered flexibility in our incentive, providing options for a check or donation on their behalf. As a result, we were able to successfully recruit respondents for this work.

The comprehensive market information gathered through this effort will be critical for understanding the potential for heat pump adoption across different residential buildings in California. The findings inform every aspect of the market including avoiding natural gas infrastructure, designing new construction buildings, modeling heat pump systems in Title 24 compliance software, purchasing them from suppliers, installing them in retrofit scenarios, and maintaining them once installed. Other findings included technical limitations of heat pumps, contractor misperceptions, and customer concerns. The primary cost data will be used to improve heat pump adoption models, necessary market interventions, and contractor training. The baselines established in this study will be a point of comparison to measure market impacts from heat pump programs over time. Finally, this study provides actionable information for utilities on effective heat pump program design strategies, including incentive structures, targeted marketing, and trade ally support.


[1] SB 100, Pavley. California Renewables Portfolio Standard Program: emission of greenhouse gases. https://leginfo.legislature.ca.gov/faces/billNavClient.xhtml?bill_id=201720180SB100

[2] Temple, James. “California advances an ambitious climate policy that should be a model for the world.” MIT Technology Review, August 28, 2018. https://www.technologyreview.com/2018/08/28/2152/california-advances-an-ambitious-climate-policy-that-should-be-a-model-for-the-world/