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Most buildings still rely on fossil energy --- such as oil, coal and natural gas --- for heating. This is because they are readily available and have higher heat value than their cleaner counterparts. However, these primary sources of energy are also high pollutants. As the grid moves towards eliminating CO 2 emission, replacing these sources of energy with cleaner alternatives is imperative. Electric heat pumps --- an alternative and cleaner heating technology --- have been proposed as a viable replacement. In this paper, we conduct a data-driven optimization study to analyze the potential of reducing carbon emission by replacing gas-based heating with electric heat pumps 1 . We do so while enforcing equity in such transition. We begin by conducting an in-depth analysis into the energy patterns and demographic profiles of buildings. Our analysis reveals a huge disparity between lower and higher income households. We show that the energy usage intensity for lower income homes is 24% higher than higher income homes. Next, we analyze the potential for carbon emission reduction by transitioning gas-based heating systems to electric heat pumps for an entire city. We then propose equity-aware transition strategies for selecting a subset of customers for heat pump-based retrofits which embed various equity metrics and balances the need to maximize carbon reduction with ensuring equitable outcomes for households. We evaluate their effect on CO 2 emission reduction, showing that such equity-aware carbon emission reduction strategies achieve significant emission reduction while also reducing the disparity in the value of selected homes by 5X compared to a carbon-first approach.
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Heating with justice: Barriers and solutions to a just energy transition in cold climates
Residential heat pumps could reduce greenhouse gas emissions, but increase energy burdens, the proportion of income households spend on utility bills. We analyze utility bills, thermostat settings and energy burdens for a sample of 51 households in Michigan, half below median income. We recruit a contractor to conduct energy assessments of these households and provide them with energy retrofit recommendations, including estimated costs and savings. We find that low-income households choose similar temperature setpoints to higher-income households, but live in less efficient homes. Below-median income households, which today experience a median energy burden of 6%, would see it rise to 10% if they shifted to electric heat pumps from natural gas. Weatherization could offset this increase, bringing burdens down to pre-electrification levels. However, median payback is 24 years, making retrofits infeasible for the poorest. Our results are indicative of an energy poverty trap that could hinder an equitable energy transition.
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- Award ID(s):
- 1952038
- PAR ID:
- 10527674
- Publisher / Repository:
- ScienceDirect
- Date Published:
- Journal Name:
- Resources, Conservation and Recycling
- Volume:
- 208
- Issue:
- C
- ISSN:
- 0921-3449
- Page Range / eLocation ID:
- 107699
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
-
Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.1016/j.resconrec.2024.107699
