Quantifying the impact of residential space heating electrification on the Texas electric grid

Abstract In this technical analysis, we studied the effects of complete electrification of space heating in the Texas residential sector on the energy consumption, peak power demand, and grid capacity utilization in the Electric Reliability Council of Texas (ERCOT) electricity grid. We utilized the National Renewable Energy Laboratory’s (NREL) ResStock tool to develop geographically representative housing stock models and the physics-based EnergyPlus modeling software to create an aggregate building stock energy model that represents the residential sector in the ERCOT operating region. In this aggregate building energy model, we replace all natural gas and other fossil-fuel furnaces with reversible electric heat pumps of varying efficiencies that can provide heating in the winter and cooling in the summer. We integrate spatially-resolved actual meteorological weather data with the building stock energy model to simulate a specific year (2016) of hourly-resolved energy usage in the ERCOT region. We find the annual electricity consumption, peak hourly power demand for each day, and load duration curves for each of 17 regions within ERCOT. From the base case, the absolute winter peak electrical power demand in the residential sector could increase by as much as 36%, or 12 GW. These results indicate that grid capacity would need to increase by  10 GW (a  25% increase for the residential sector) to accommodate a winter peaking residential sector. Though winter electricity consumption would increase for home heating, the annual amount of electricity consumption would stay roughly the same or decrease because the higher efficiency heat pumps provide more efficient cooling than the conventional air conditioners they also replace. Using average 2018 emissions rates, we estimate a change to standard efficiency heat pumps would lead to a 4.1% reduction of CO2 emissions and a 5.8% reduction of NOx emissions from the residential sector. There is no significant change in SOx emissions in our standard efficiency scenario, but in the high and ultra-high aggregate efficiency scenarios, SOx emissions are reduced by 8.3% and 15.0% respectively.