ENERGY SECURITYStudy Projects Geothermal Heat Pumps’ Impact on Electrical Grid, Carbon Emissions
New study gives the first detailed look at how geothermal energy can relieve the electric power system and reduce carbon emissions if widely implemented across the United States within the next few decades.
A modeling analysis led by the Department of Energy’s Oak Ridge National Laboratory gives the first detailed look at how geothermal energy can relieve the electric power system and reduce carbon emissions if widely implemented across the United States within the next few decades.
Researchers created a simulation model of the mass deployment of geothermal heat pumps, or GHPs, in commercial and residential buildings from 2022 through 2050. The simulation results indicated that if GHPs, also known as ground-source heat pumps, were deployed on a national scale along with building envelope improvements in single-family homes, the stress on the power grid would be relieved, energy costs lowered and carbon dioxide emissions reduced substantially.
“GHPs have traditionally been seen as a building energy efficiency technology,” said ORNL’s Xiaobing Liu, who served as the primary researcher on the study. “This analysis found that GHPs have a tremendous impact on electric power systems by reducing the requirements in capacity, generation, and transmission, as well as carbon emissions.”
Groundbreaking Numbers
GHPs provide an environmentally friendly, energy-efficient alternative to conventional heating, ventilation and air-conditioning, or HVAC, systems. They operate by transferring heat to and from the ground through underground pipes. The pipe system extracts heat from the ground to warm buildings in the winter while using the ground as a heat sink to cool buildings in the summer.
Liu said that mass GHP deployment in both commercial and residential buildings, coupled with building envelope improvements in single-family homes, can reduce more than 7,000 million metric tons of carbon emissions through 2050, with more than 3,000 million metric tons of reduction coming from the electric sector and the remaining coming from the replacement of natural gas for heating in the building sector.
“It is well understood that GHPs are beneficial for lowering building energy costs because of their high efficiency and ability to supply heat without fuel purchases, resulting in zero on-site emissions,” Liu said. “Until now, though, few studies have investigated the impacts of large-scale deployment of GHPs on the electrical grid.”
