Home Energy Survey Results

This post reports quantitative results from both the first general home energy survey launched on November 28 and the follow-up survey on affordability launched on December 4.

Survey outreach and response

The survey was distributed through email to 4,610 people who have voluntarily subscribed to my office email list. Email reminders were sent in three waves. The third wave used a pleading subject line — “Even if home energy is not a priority for you . . ..” In addition, the survey link was posted to two Allston-Brighton group email forums and to the Belmont Parents Facebook Forum. The survey was anonymous, but the links used allowed us to identify which outreach method people were responding to, as shown in Table 1. The first email was sent on November 28 at 4PM and the survey was closed on December 2 at 8AM.

Table 1: Survey responses by date and outreach type
 28-Nov  29-Nov  30-Nov  1-Dec  2-Dec  TotalResponse
WB Office Email list 1,027        658         249         100         12,03544%
A-B email forum            17             1               18n/a
Belmont FB page            16             3               19n/a
Total 1,027         658         282         104         12,072n/a
Note: The total response was 2,083. 1 response with an unrecognizably invalid zip code and 10 apparently repetitive submissions were deleted (six out of a group 7 and 4 out of a group of five fully identical submissions). There were 74 pairs and 3 triples with the same IP address, including 16 with both the same IP address and the same browser type, but spot checking suggested that these were not all clearly duplicate responses and they were not eliminated or consolidated.


The survey asked only the following demographic questions: zip code, own or rent, and length of residence at current addressed.

The responding sample is centered in Belmont, Watertown, and Boston, but includes 116 zip codes.

Table 2: Distribution of responses by city/town (N=2,072; 116 zip codes represented)
City/TownResponseResponse %
Other 1517%
Note that “Other” includes 8 non-MA (or possible typo) zip codes.
Table 3: Distribution of responses by own/rent and length of residence (N=2,072)
< 1 year1-5 yearsOver 5 yearsTotal

Although renters are well represented in the sample, the sample is skewed toward homeowners and longer-term residents. Renters and homeowners were served a different version of the critical final question on willingness to spend more to be carbon free, so this skew does not affect that answer. As Table 4 shows, however, within both the renters and homeowner categories, the sample skews towards those who have lived longer at the same address.

Table 4: Comparison of Sample to Statewide Average — own/rent; moved in within last year
Sample (N=2,072)Statewide Census 2021
% of owners moved in within last year2%7%
% of renters moved in within last year2%11%
Statewide Source: American Community Survey Data, accessed using the census JSON API: https://api.census.gov/data/2021/acs/acs1?get=NAME,group(BG117)&for=state:25&key=Your_API_Key_Here and https://api.census.gov/data/2021/acs/acs1?get=NAME,group(B07013)&for=state:25&key=Your_API_Key_Here. Find more about ACS data here.

Building Types and Heating Sources

The sample includes a good mix of building types for both owners and renters (although rented single family homes are not common):

Table 5: Building Type by own/rent (N=2,072)
Single FamilyTwo to Four UnitsFive or More UnitsGrand Total
Grand Total47%31%22%100%

Gas heat dominates among both renters and owners in the sample. Gas dominates statewide, but the dominance is a little stronger in this sample; correspondingly, fuel oil is a little weaker in the sample. Electric resistance heat is most common in rental properties — cheap for the landlord to install, although expensive for the renter to operate. Compare statewide census data here.

Eight percent of the homes in the sample already have heat pumps as the primary heating source. That is loosely consistent with data in the state’s climate plan for 2020 which had two percent of homes with whole home heat pumps and eight percent with “partial-home” heat pumps. The state-wide data are unclear as to what portion of the “partial-home” pumps are the “primary heating source.”

Table 6: Primary Heating Source by own/rent (N=2,072)
Primary Heating SourceOwnRentGrand Total
Fuel oil17%16%17%
Utility gas67%54%65%
Electric Resistance4%14%6%
Heat Pump9%2%8%
Wood, Propane, Hybrid*, etc.1%1%1%
Grand Total100%100%100%
*The “Hybrid” category was added mid-stream, about half-way through the response process. About 15 or 20 respondents with mixed systems (for example, heat pumps together with an oil boiler for coldest weather) had complained that the survey did not give them a valid option. The survey asked people to choose their primary source of heat, but some people with mixed systems had trouble interpreting that — they might not actually know which component of their system is the primary source. They sent email inquiries and we added the hybrid option. However, only 8 among the over 1000 respondents who did see the hybrid option chose it. Most people were comfortable designating a primary source.

Analysis for small building homeowners

This section focuses on results for homeowners in single family and two to four unit buildings. Homeowners in larger buildings are likely to have less direct control of investments. In addition, the analysis is limited to buildings heated with gas or oil. Other than heat pumps, these are the major heating sources in the sample.

Table 7: Subsample Definition
Sample portionNumber included% of full sample
Full sample2,072100%
Owners 1,64179%
One to four unit buildings 1,37766%
Oil, gas or heat pump heating1,32064%
Oil or gas heating 1,21058%

In the subsample, the major heating distribution methods are roughly the same for the two major sources.

Small Building Homeowners Table 1: Heating Distribution Mode by Heating Source (N=1,210)
BaseboardsHot Water RadiatorsSteam RadiatorsHot Air Ducts/VentsOther/
Fuel Oil13%38%27%20%3%100%
Utility Gas13%39%19%26%3%100%
Small Building Homeowners13%39%21%25%3%100%

In this sample, almost half of the homes apparently have some form of ducting that could perhaps be used to distribute seasonally hot or cold air from heat pumps, avoiding the need to install minisplit units in multiple rooms.

Small Building Homeowners Table 2: Vents/Ducts available for heat pump use
Vents/Ducts presence for heating and/or coolingN%
Vents/ducts for heating only776%
Vents/ducts for central air only25821%
Vents/ducts for heating and central air22018%
Subtotal: Some form of vents/ducts55546%
No vents/ducts65554%
Note: Respondents were not specifically asked how their central air conditioning was distributed; we are interpreting “central air” as ducted because minisplits and window/wall air units were alternative answers for respondents.

In this sample of small building homeowners, 77% have taken some action steps towards energy efficiency — either an energy audit, weatherization, or any use of Mass Save. Another 15% are aware of Mass Save, although they cannot recall having taken any actions. Only 9% have taken no action steps towards energy efficiency and have no awareness of Mass Save.

These data may suggest uniquely high engagement with Mass Save and energy efficiency. However, since 2010, Mass Save has been spending hundreds of millions of dollars every year to do audits and support energy efficiency measures. Mass Save claims millions of participants each year. These claims involve massive double counting — in one year, 2020, Mass Save claimed 7.9 million participants in its electric programs alone. (See current Mass Save three year plan packet at page 277.) That is more participants than there are people in Massachusetts, 7.0 million in 2020, and many more participants than there are homes, only 2.7 million. An unduplicated historical count of Mass Save participants would be useful to have, but it seems possible that the present sample, as to its high level of engagement, may be representative of the state. More about Mass Save spending here.

Small Building Homeowners Table 3: Energy Efficiency Engagement
Engagement TypeCount% of
Used Mass Save68457%
Made weatherization investments70458%
Done energy audit71159%
Any of the above actions92977%
Familiar with Mass Save but taken none of above actions17715%
Unfamiliar with Mass Save and taken none of above actions1049%
Small Building Homeowners1,210100%
“Unsure” responses were treated as unfamiliar or no action.

The final critical question for homeowners in the survey was about willingness to invest to go carbon free for heating. The table below summarizes the answer to that question. It is apparent that the more familiar people are with heat pumps, the more likely they are to be willing to invest in them. One could dismiss that correlation as merely showing that those inclined to convert to heat pumps have taken the time to learn about them. But, since only 8% of the sample was categorically uninterested in investing to reduce carbon emissions, the correlation seems encouraging — as consumer awareness of heat pumps builds, more people will want to convert.

Small Building Homeowners Table 4: Familiarity with heat pumps vs. response to question “Would you spend $6000 to cut carbon emissions by converting your fossil fuel heat system to a clean heat system like electric heat pumps?”
Not familiar with heat pumps
(N=357; 30%)
Generally familiar with heat pump (N=577; 48%)Very familiar with heat pumps
(N=276; 23%)
(N=1,210; 100%)
No, fine with fossil8%6%10%8%
No, already non-fossil1%1%8%3%
Depends on bill impact27%36%30%32%
Yes, even if bills go up9%18%28%17%
Grand Total100%100%100%100%

This question, as worded, assumes what is likely a best case scenario — a $16,000 heat pump conversion with a $10,000 whole home Mass Save incentive, resulting in a net consumer cost of $6,000. That is only likely to work out in a home that is already well insulated and is equipped with ducts for heating and/or cooling. Even in those homes, upfront costs may be higher. Clearly, many home-owners have to be cost-sensitive.

Results from follow-up on cost-sensitivity

To further explore the cost-sensitivity of homeowners, we sent a follow up survey. The follow-up was sent in two waves on December 4 and December 6 to 2,362 email addresses who, according to Mailchimp, had clicked to view the previous survey. Both surveys were anonymous, but it appears likely that most of those 2,362 had responded to the previous survey (since 2,035 had responded to the first survey via the mailing).

879 people responded to the follow up survey. This was a 37% response rate — lower than expected since most were responders to the first survey. This drop off may have reflected either survey fatigue or confusion as to whether it was a new survey. Either way, the respondents to this survey are likely even more interested in home energy issues than the prior sample.

The first question in the survey was whether the respondent met all of the following criteria: (a) homeowner; (b) in a building with less than five units; (c) heating with gas or oil. 692 respondents (79%) met these criteria. These respondents are thus mostly a subsample of the 1,210 respondents who were included in the “Small Building Homeowner” tables above.

Small Building Homeowner Follow-up Table 1: I would consider replacing my current fossil heating system with a heat pump before it wears out.
Grand Total692100%
Small Building Homeowner Follow-up Table 2: How do you feel about “minisplit” units being mounted in several rooms in your home?
Not needed; have vents/ducts.16324%
I’m ok with minisplits.25236%
I’m not ok minisplits.9614%
I’m not sure how I feel.18126%
Grand Total692100%
Small Building Homeowner Follow-up Table 3: Which statement best characterizes your thought process about converting to heat pumps?
1 — I am not interested in converting to heat pumps.7110%
2 — I would compare the upfront costs to the annual heating cost savings which might come from the conversion and would move forward if it were cost effective for me and my family.23834%
3 — I would think carefully about how much we could afford to spend up front and also about whether we could absorb any heating cost increases. Cutting carbon is very important, but I can only do so much myself.33749%
4 — I am not cost sensitive for upfront costs up to $50,000 or annual heating bill increases up to $1,000 per year. I want to cut my carbon footprint and can afford do so.467%
Grand Total692100%
Note: The “not interested” option was not available to the first 86 among the total 879 respondents, so it may be slightly under-represented.

The 337 who gave response 3 to the preceding question — those who would spend to reduce carbon if they could afford it — were asked two additional questions:

Small Building Homeowner Follow-up Table 4 (N=337 — reduce carbon if affordable): How large an annual heating cost increase could you absorb?
I couldn’t. I need cost savings.165%
Zero, but break even is OK.4513%
Up to $200 per year6118%
Up to $400 per year.7021%
Up to $600 per year.8525%
I can’t guess.6018%
Grand Total337100%
Small Building Homeowner Follow-up Table 5 (N=337 — reduce carbon if affordable): How large an upfront investment could you make (NET of rebates and tax credits)?
Zero. I need a full subsidy.5416%
Up to $6,0008726%
Up to $10,0008826%
Up to $20,0005015%
Up to $30,000206%
I can’t guess.3811%
Grand Total337100%
Small Building Homeowner Follow-up Table 6 (N=258– reduce carbon if affordable; exclude unsure on affordable levels): Cross-tab of annual vs. upfront affordability
Average 1,2004,7696,79310,72715,0259,721
Average is the count-weighted average for the row (upfront affordability) or column (operating affordability)

Small Building Homeowner Follow-up Table 6 shows that, as one would expect, judgments about annual affordability are highly correlated with judgments about upfront affordability. People do not mentally combine upfront and annual affordability and trade one against the other as a business analyst might do. Additionally, it is reasonable to guess that annual cost increases correlate with upfront investments — larger homes that require large heat pumps are likely to have higher heating requirements and the possibility of higher operating cost increases (especially for gas heated homes). The exception to this would where large upfront weatherization investments cut operating costs; here we are focusing on the heat pump decision in isolation.

The following summary assumes that operating cost considerations wash out — for those who want to convert to heat pumps subject to affordability, the primary consideration is up front cost.

Small Building Homeowner Follow-up Table 7 (N=692): Summary of likelihood to convert results
Combined affordability and other likelihood to convert factors% of sample
1 Not interested in heat pumps10%
2 Will convert only if cost-effective based on both operating and capital costs34%
3 Will convert only if net upfront cost under $10,00033%
4 Unsure how much they can afford5%
5 Can afford net over $10K, but need minisplits and not OK or unsure about them5%
6 Can afford net over $10K, and have vents or are OK with minisplits, but will not consider replacing before failure1%
7 Can afford net between $10K and $30K, and have vents or are OK with minisplits and will consider replacing before failure6%
8 Can afford net up to $50K, and have vents or are OK with minisplits and will consider replacing before failure5%
9 All homeowners in follow up affordability survey (N=692)100%

Interpretation of affordability results

Hybrid systems — using heat pumps in the shoulder seasons but gas or oil in the depth of winter — do not cut emissions deeply because the greatest heating loads occur when the weather is cold. Since our interest is in achieving climate goals, we will compare the survey affordability statements to the costs of whole home conversions using cold-climate heat pumps that do not require fossil backup.

Whole-home conversions currently cost an average of $21,000 ($11,000 after Mass Save $10,000 incentive) in a recent study by the Massachusetts Clean Energy Center. Additionally, many homes will need to invest in weatherization before conversion. So the net project costs are likely to be over $10,000 and sometimes well over $10,000. Few of those respondents in lines 1 through 6 would go forward and only a portion of those in line 7 would go forward based on the economics. (For more on operating costs and cost-effectiveness, see this page.) The numbers are imprecise, but it would appear likely that the share of the sample for whom the economics support conversion may be on order of 10%.

In all categories, some will fail to go forward, even when the economics meet their stated parameters, because the process is complex and requires considerable effort. In practice, the number within this sample that will actually convert will almost certainly be well under 10% with current incentives.

This is a highly motivated sample. I talk a lot about climate change. People on my mailing list are diverse in their views, but skew towards having climate concerns. This sample of respondents consists of those within that universe who were willing to respond to a second home energy survey within a few days of the first. So, the statewide willingness to convert has to be considerably less. The data here are consistent with “potential studies” showing negligible annual rates of gas home conversion and low single digit annual rates of oil conversions.

Analysis for large building condo owners

This subsample selects from among the 260 homeowners who reside in buildings of 5 or more units the 177 who heat with oil or gas. These homeowners were asked the same willingness-to-invest question that the smaller building homeowners were asked. Overall, their responses show somewhat less familiarity with heat pumps and somewhat higher uncertainty, but also more willingness to absorb cost increases to go carbon free. However, as several wrote to me to point out, condo associations may be inflexible even as to individual unit changes and condo owners face daunting challenges in persuading their condo associations to invest in building-wide systems changes.

Large Building Condo Owners Table 1: Familiarity with heat pumps vs. response to question “Would you spend $6000 to cut carbon emissions by converting your fossil fuel heat system to a clean heat system like electric heat pumps?”
Not familiar with heat pumps
(N=74; 42%)
Generally familiar with heat pumps
(N=71; 40%)
Very familiar with heat pumps
(N=32; 18%)
(N=177; 100%)
No, fine with fossil1%4%9%4%
No, already non-fossil3%3%3%3%
Depends on bill impact26%21%16%22%
Yes, even if bills go up.15%23%34%21%
Grand Total100%100%100%100%

Analysis for Renters

Since renters would not generally contribute any lump sum towards carbon emissions reduction, the question to renters would how much additional rent they would pay.

Renters show much less familiarity with heat pumps and appear generally more cost-sensitive than either category of homeowners — understandably since they have no direct control over heating system decisions and no assurance that they will capture long term benefits. The questions are not directly comparable, but spending $6000 up front with the potential for increasing bills (as in the most willing category in the previous two tables) is a greater investment than the greatest investment in the table below (additional $50 per month) — yet, more owners were willing to make the top offered investment level than renters.

Renter Table 1: Familiarity with heat pumps vs. response to question “How much higher monthly rent would you pay to have zero carbon heat?”
Not familiar with heat pumps
(N=285; 66%)
Generally familiar with heat pumps
(N=112; 26%)
Very familiar with heat pumps
(N=34; 8%)
(N=431; 100%)
Zero — I wouldn’t11%7%18%10%
Under $5035%40%18%35%
Over $5012%25%18%16%
Grand Total100%100%100%100%

Given that rents fluctuate (generally rising), the question of whether one would pay a certain additional rent to be carbon free is an abstract one, less directly translatable into a practical decision than the question posed to homeowners.

Underlying Data

This Excel workbook contains the individual anonymous survey results and the tabulations presented for the first survey. The anonymous results for the follow-up survey are in this workbook.

Return to heat pump outline

Published by Will Brownsberger

Will Brownsberger is State Senator from the Second Suffolk and Middlesex District.