Energy-Efficient Upgrades in Urban Low-Income Multifamily Housing: Energy Burdens and Lessons Learned for Best Sustainability Practices

Round 1

Reviewer 1 Report

Comments and Suggestions for Authors

Overall, the article evaluates an energy efficiency upgrade program in low-income multifamily housing using a Community-Based Participatory Research (CBPR) approach, which is innovative and practical. However, the article falls short in sample size, actual energy-saving effects, stratified analysis of energy burden, actual cost savings, and quantitative analysis of changes in residents' behavior. It is recommended that the authors address these issues to further enhance the quality and academic value of the article.
1. The article evaluates an energy efficiency upgrade program in low-income multifamily housing in Detroit using a Community-Based Participatory Research (CBPR) approach, but the small sample size limits the generalizability and statistical significance of the results.
2. While discussing the impact of Energy Conserving Measures (ECMs) on residents' energy use, the article provides survey results on residents' satisfaction with the upgrades but lacks a detailed analysis of the actual energy consumption and cost savings associated with these measures. 
3. While analyzing residents' energy burden, the article mentions the definition and calculation method of energy burden but lacks a stratified analysis of energy burden across different income levels. For example, although the study found that low-income residents had a high energy burden, no detailed comparison was made across different income brackets (e.g., below 10,000-20,000.
4. While discussing the economic feasibility of energy efficiency upgrades, the article mentions the theoretical energy savings achievable through these measures but lacks a detailed analysis of actual cost savings.
5. While discussing residents' feedback on energy efficiency upgrades, the article provides qualitative feedback but lacks a quantitative analysis of changes in residents' behavior.

Author Response

Comment 1: The article evaluates an energy efficiency upgrade program in low-income multifamily housing in Detroit using a Community-Based Participatory Research (CBPR) approach, but the small sample size limits the generalizability and statistical significance of the results.

Response 1:  We recognize the sample size is a limitation but the value of the work is reflected in the number of participants who elected to lend their time and homes to this study based on their energy experiences. We have added additional discussion to the limitations section on page 26, line 690, as follows:

“The overall size of our sample of participants was relatively limited at 39, but this was due in part to a limited budget for this research. Costs included staff time, transportation, and participant incentives. However, given the paucity of research in this field, we feel that evidence from this work may be of use for promoting sustainability and equity in the future.”

Comment 2: While discussing the impact of Energy Conserving Measures (ECMs) on residents' energy use, the article provides survey results on residents' satisfaction with the upgrades but lacks a detailed analysis of the actual energy consumption and cost savings associated with these measures. 

Response 2: Thank you so much for this comment. As we discuss in our revised text, multiple factors influence energy consumption in a household and isolating the effect of the ECMs on energy consumption poses challenges because of weather, not knowing how much electricity participants consume on a day to day basis from appliances etc. We did our best to analyze potential cost savings and also report participant experiences with the measures as these are also important qualitative measures of impact.

The new text on page 23, line 600 reads: "Multiple factors influence energy consumption in a household, and isolating the effect of the upgrades on energy consumption poses challenges because of weather, uncertainty about how much electricity residents consume daily due to appliance use, and other factors. Yet, our analysis of both potential cost savings and participant experiences with measures provides qualitative and quantitative measures of impact."

Comment 3: While analyzing residents' energy burden, the article mentions the definition and calculation method of energy burden but lacks a stratified analysis of energy burden across different income levels. For example, although the study found that low-income residents had a high energy burden, no detailed comparison was made across different income brackets (e.g., below 10,000-20,000.)

Response 3: Our small sample size limits the ability to make meaningful conclusions with stratified analysis, especially because only 2 people reported earnings in the higher income category and 20 in the lower income category. In addressing this comment, we noticed an error in Table 2 (page 11)  where 2 participants should not have been included and therefore have made the correction. In addition, for one of the participants, income information was reported, and therefore, we have corrected the table to address this.

Comment 4: While discussing the economic feasibility of energy efficiency upgrades, the article mentions the theoretical energy savings achievable through these measures but lacks a detailed analysis of actual cost savings.

Response 4: We provided theoretical energy savings because we can’t confidently attribute cost savings specifically to the ECMs given other determinants of energy consumption. In Table 7 (page 18), we compare average monthly electricity costs before and after the energy efficiency upgrades were installed. Since this is a community-based project where electricity bills were collected from residents in person, we do not have detailed electricity consumption data for every household in each month and experienced difficulty accessing bills from the utility’s website, even with participants present. We have pointed out this information in the limitations section on page 26, paragraph 2, in lines 690-693. Thank you for this comment.

Comment 5: While discussing residents' feedback on energy efficiency upgrades, the article provides qualitative feedback but lacks a quantitative analysis of changes in residents' behavior.

Response 5: Please see above responses.

 

Reviewer 2 Report

Comments and Suggestions for Authors

Review 9 April 2025

Dear Authors,

 

Your paper is important for reducing energy consumption and better managing it. As your reviewer will also give this area, including from the household side (you can see: https://doi.org/10.3390/en17112483).

My main notes:

Note 1: Abstract: After the sentence “This study examines the energy-related experiences of low-income families in Detroit, Michigan, who received energy-conserving measures (ECMs) such as efficient light bulbs, faucets, thermostats, and refrigerators in 26 2022.” Add the new sentence (lines) about scope of research (sample).How many of participants were?

Note 2: Introduction; After the lines” The goal of this study is to examine energy and cost savings resulting from a utility offered energy efficiency program carried out in a low-income multifamily community of  town home-style units in Detroit, Michigan.? Please add the research questions RQs: in the form: RQ1…? RQ2…? And RQ3…….

Note 3: Before the section: Materials and Methods, please add the new section: Relater work. In this new section do the short literature review, show the key problem of fields research of other authors.

Note 4: Materials and Methods. In this section must me more  information about the research structure and the statistical significance of your research. Subsections; Survey analysis must be strongly improved.

Note 5: 3.1. Survey analysis. For 39 participant you use results in % ,  it's too small a sample to show percentages, leave the numbers.

Note 6: In tables don’t use % for me. Table 1 for N=7 in % why for 7 participant you use %, this information is not important to your analysis.

Table 3, the same situation, N=1 and 2.6% for answer: Don’t know 1 (2.6%) Somewhat disagree etc. etc.

Table 4 the same situation 1 (2.6%)

Too small sample to show shares, do a different analysis, not percentage.

Fig. 2 Reports on which energy conserving measures (ECMs) were most beneficial by 39 residents… I see on the picture (Fig. 2) the maximum 25 where is the rest

 

Note 7: The section about costs.

This is an important section, but is it strongly connected with the previous results of your research, for me these are two areas of work, one about consciousness and the other about economics, how did you connect them, are these drawings in the appendix (maybe add them to the text).

Note 8. Add the nea section: Limitation of research and future reserach (before Conclusion)

Not 9: Please add more paper to references.

If you create the Related Works section after the Introduction, it will be even better.

Best wishes

Reviewer

Author Response

Comment 1: Your paper is important for reducing energy consumption and better managing it. As your reviewer will also give this area, including from the household side (you can see: https://doi.org/10.3390/en17112483).

Response 1: Thank you very much for this compliment.  We are happy to see this other reference from work in this area and have cited it in the related works paragraph of the introduction section, beginning on page 2, line 80, as seen in the tracked changes.

“A study in Poland suggests financial assistance, subsidies, and tax incentives combined with narratives that promote energy-saving behaviors are socially desirable ways to drive energy-efficient behaviors among low-income residents and help overcome cognitive and behavioral barriers to energy efficiency.”

Comment 1.1: Abstract: After the sentence “This study examines the energy-related experiences of low-income families in Detroit, Michigan, who received energy-conserving measures (ECMs) such as efficient light bulbs, faucets, thermostats, and refrigerators in 26 2022.” Add the new sentence (lines) about scope of research (sample).How many of participants were?

Response 1.1: Thank you for your comment. We have updated the abstract to include more detailed information about the number of participants, as follows on page 1, lines 28 and 29 as follows.

“39 residents completed surveys and provided energy usage data before and after the upgrades; 12 residents provided hourly energy usage.”

Comment 2: Introduction; After the lines” The goal of this study is to examine energy and cost savings resulting from a utility offered energy efficiency program carried out in a low-income multifamily community of  town home-style units in Detroit, Michigan.? Please add the research questions RQs: in the form: RQ1…? RQ2…? And RQ3…

Response 2: Research questions have been added in this section on page 3, beginning on line 117, using the suggested format. Thank you for your comment. 

“RQ1: What energy and monetary savings could public housing residents obtain from participating in a utility-offered energy efficiency program?

RQ2: What are the challenges associated with implementing an energy efficiency program in public housing?

Comment 3: Before the section: Materials and Methods, please add the new section: Relater work. In this new section do the short literature review, show the key problem of fields research of other authors.

Response 3: A related works paragraph has been added to the introduction of the paper, beginning on page 2, line 80. 

“Prior work in this field is relatively limited. A review of research on residential energy efficiency interventions in low-income households indicates significant variation in the impacts of these programs, driven by populations involved, installation of measures, types of measures involved, and the ways installed measures affect household behaviors [6]. In some of the reviewed studies, residential energy efficiency interventions led to savings, while other interventions led to small or negative savings [6]. A study in Poland suggests financial assistance, subsidies, and tax incentives combined with narratives that promote energy-saving behaviors are socially desirable ways to drive energy-efficient behaviors among low-income residents and help overcome cognitive and behavioral barriers to energy efficiency [7]. Ultimately, families living with low income are making difficult tradeoffs and foregoing essentials to heat and cool their homes. Frank et al use the term “heat or eat” to describe this type of dilemma, where residents must choose between spending money on heating their homes or food [8]. Hernandez and Bird cite the Low-Income Home Energy Assistance Program and Weatherization Assistance Program as the two most notable U.S. federal resources for low-income households [9]. The authors, however, note that these programs are historically vulnerable to budget cuts, weakening their reliability as resources for relief from energy hardship. Energy-efficient retrofits provide a clear path to cost savings at the household level [9]. While programs that carry out these upgrades provide viable intervention strategies, they must be refined to make the benefits more accessible and enhance sustainability at a societal level. To effectively reach those families most in need, detailed individual household energy data is needed. Reames describes the proprietary nature of energy data as a significant barrier to successful programs, where utilities are concerned about customer privacy or are not incentivized to support projects that could jeopardize revenues [10]. Considering this barrier, holistic and community-based approaches to energy efficiency can be applied to reach sustainability goals.”

Comment 4: Materials and Methods. In this section must me more  information about the research structure and the statistical significance of your research. Subsections; Survey analysis must be strongly improved.

Response 4: Thank you for this comment, we have made changes to provide more information on the research structure, including the management platform used to administer the surveys. Specifically, on page 5, line 201, we added the sentence: “We designed a survey to capture key characteristics of participants as well as their experiences with energy use and financial burden thereof prior to and after the planned upgrades (please see details below) to support evaluation.”

Comment 5: 3.1. Survey analysis. For 39 participants you use results in % ,  it's too small a sample to show percentages, leave the numbers.

Response 5: We have made all of the suggested changes to remove percentages and include numbers only. Thank you for this suggestion.

Comment 6: In tables don’t use % for me. Table 1 for N=7 in % why for 7 participant you use %, this information is not important to your analysis.

Response 6: Thank you for this suggestion. We have made the change. Because track changes of this made the paper appear cluttered, we did not track them, but changes were made where requested.

Comment 7: Table 3, the same situation, N=1 and 2.6% for answer: Don’t know 1 (2.6%) Somewhat disagree etc. etc.

Response 7: Thank you for this suggestion. We have made the change.

Comment 8: Table 4 the same situation 1 (2.6%)

Response 8: Thank you for this suggestion. We have made the change.

Comment 9: Too small sample to show shares, do a different analysis, not percentage.

Response 9: Thank you for this suggestion. We have made the change.

Comment 10: Fig. 2 Reports on which energy conserving measures (ECMs) were most beneficial by 39 residents… I see on the picture (Fig. 2) the maximum 25 where is the rest

Response 10: Thank you for this comment. Participants were able to select multiple upgrades they believed they benefited from. We asked the question of all 39 participants, but here are only reporting the ‘n’ of upgrades that were reported as beneficial. No single upgrade was perceived as the most beneficial by participants, making 21 the greatest number associated with a single upgrade.

To make this more clear in the Figure, we have changed the caption on the figure on page 16, line 468 to read, “Figure 2. Reports on which energy-conserving measures (ECMs) were most beneficial asked of 39 residents of The Villages at Parkside, Detroit, MI, 2023. The chart shows the number of study participants who selected each of the above energy-conserving measures (ECMs) as a response to the post-intervention survey question: “Which energy upgrade do you feel you benefited the most from?” Participants could select more than one ECM if they thought they benefited the most from multiple ECMs.”

Comment 11: The section about costs.

This is an important section, but is it strongly connected with the previous results of your research, for me these are two areas of work, one about consciousness and the other about economics, how did you connect them, are these drawings in the appendix (maybe add them to the text).

Response 11: Thank you for this comment. We have added the figures from the appendix to the text, as requested (Figure 3). 

We conducted additional analyses plotting the outside temperature against electricity use for 12 households with hourly outside temperature data and electricity use. Figure 3 illustrates that households that use space heaters extensively during the fall and winter months are particularly impacted by additional outside temperature-dependent electricity use costs  

To better connect the analyses in this paper, we have added a sentence on page 20, line 552:

“These more quantitative analyses (Figure 2) on a subset of participants in the study illustrate potential ways to capture savings and energy use, even with limited sample size, and thus complement the survey results from the larger sample."

Comment 12: Add the nea section: Limitation of research and future research (before Conclusion)

Response 12: We previously included our limitations as part of the discussion. A limitations section has been added on page 25, line 680. Thank you for your comment.

Comment 13: Please add more paper to references.

If you create the Related Works section after the Introduction, it will be even better.

Response 13: Thank you for your comment. A related works paragraph has been added to the paper with corresponding additional references. 

Round 2

Reviewer 1 Report

Comments and Suggestions for Authors

no comments

Author Response

Reviewer Comment 1: N/A

Response 1: Thank you for your feedback and support with improving this article. 

Reviewer 2 Report

Comments and Suggestions for Authors

Dear Authors,

After your corrections, the paper is already better, but I still miss a strong argument for the sufficiency of 39 study participants, as well as the lack of a Background of analysis (research) section, which results in few scientific publications in the references.

 

Author Response

Reviewer Comment 1: After your corrections, the paper is already better, but I still miss a strong argument for the sufficiency of 39 study participants, as well as the lack of a Background of analysis (research) section, which results in few scientific publications in the references.

Thanks so much for these comments.

Response 1, regarding the sufficiency of 39 participants: 

We added the following sentence to the introduction, beginning on page 3, line 122.

“Additionally, the relatively scarce evidence in this area of research and practice means that even smaller studies which engage community members in documenting their experiences with home energy improvements offer valuable insights for efforts to enhance sustainability and improve quality of life.”

We added the following sentences to the limitations on page 26, line 717. 

“ In addition, enrolling participants who face numerous challenges in addition to paying for energy and multiple demands on their time can be difficult. Given the novel and challenging context, we have a small sample size, and are unable to claim that these participants--or are findings--are representative. However, we believe that the results are a useful source of hypotheses, which larger studies can seek to test.”

Response 2, regarding background of research:

We have added a new paragraph to the introduction section, beginning on page 3, line 98  (quoted).

“Across low-income residents, homeowners and renters have low involvement in energy efficiency programs that, in theory, were designed to target their specific needs. Program materials that clearly outline the requirements and benefits of energy efficiency programs increase the likelihood that a resident will participate or make an inquiry to their landlord. According to Kleeman et al, uncertainty about eligibility is an especially important barrier to participation in low-income residential energy efficiency programs [10]. The authors note that this barrier encompasses uncertainty around income requirements, home repair prerequisites, and even permission from landlords [10], which applies specifically to residents living in units like those of our study participants. Multifamily housing poses unique challenges for the implementation of energy-efficient upgrades. A Swedish study found that, during the planning and design phase for energy-efficient renovations in public housing, a property developer, a consultant (contracted via public procurement), and the management team for a particular property generally met to make final determinations on program design and investment [11. However, life cycle costing was not applied during these planning meetings, nor was sustainability a priority, and, instead, the least expensive measures were approved [11]”.

We did cite a comprehensive review of literature in this field in the background (Berretta et al  2021). Rather than cite each of the individual studies reviewed in our paper, we felt it important to instead describe the major conclusions of that review in terms of the field, and selectively describe a few other studies. The goal of our paper is to present an original analysis of data and not to conduct a systematic review, we wished to be concise in presenting this work. We therefore hope that our addition of a limited amount of additional citations and background supporting the present work will satisfy the reviewer and editors.

Round 3

Reviewer 2 Report

Comments and Suggestions for Authors

Dear Authors

Now your paper is better.  I say "YE". This paper can be published.

Best wishes

Reviewer