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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This content will become publicly available on June 16, 2024
Equitable Network-Aware Decarbonization of Residential Heating at City Scale
Residential heating, primarily powered by natural gas, accounts for
a significant portion of residential sector energy use and carbon
emissions in many parts of the world. Hence, there is a push towards
decarbonizing residential heating by transitioning to energyefficient
heat pumps powered by an increasingly greener and less
carbon-intensive electric grid. However, such a transition will add
additional load to the electric grid triggering infrastructure upgrades,
and subsequently erode the customer base using the gas
distribution network. Utilities want to guide these transition efforts
to ensure a phased decommissioning of the gas network and
deferred electric grid infrastructure upgrades while achieving carbon
reduction goals. To facilitate such a transition, we present
a network-aware optimization framework for decarbonizing residential
heating at city scale with an objective to maximize carbon
reduction under budgetary constraints. Our approach operates on
a graph representation of the gas network topology to compute
the cost of transitioning and select neighborhoods for transition.
We further extend our approach to explicitly incorporate equity
and ensure an equitable distribution of benefits across different
socioeconomic groups. We apply our framework to a city in the
New England region of the U.S., using real-world gas usage, electric
usage, and grid infrastructure data. We show that our networkaware
strategy achieves 55% higher carbon reductions than prior
network-oblivious work under the same budget. Our equity-aware
strategy achieves an equitable outcome while preserving the carbon
reduction benefits of the network-aware strategy.
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- NSF-PAR ID:
- 10441156
- Date Published:
- Journal Name:
- CM International Conference on Future Energy Systems (e-Energy)
- Page Range / eLocation ID:
- 1 to 13
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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