Geothermal Heating and Cooling

Renewable HVAC

Geothermal Heating & Cooling (GHC) systems use thermal energy stored under the Earth’s surface to heat and cool homes with renewable thermal energy generated from fission at the center of the Earth and solar gain during the summer. 

This stored thermal energy can be converted to heating and cooling for homes and businesses using drilled wells, piping loops, and efficient heat pumps that transfer heat between the wells and the home or business.  In the winter, the GHC system moves the heat from the earth into the house or building; in the summer, they pull the heat from the house or building and “dump” it into the ground; and year-round, they can heat water. The heat pumps not only circulate the water/glycol mixture, they also act as an air conditioner in the summer and a heater in the winter using vapor compression processes.

GHC systems are the most energy-efficient, environmentally clean, and cost-effective space conditioning systems available, according to the Environmental Protection Agency.1 EPA found that GHC systems can reduce energy consumption—and corresponding emissions—by over 40% compared to air source heat pumps and by over 70% compared to electric resistance heating with standard air-conditioning equipment. EPA also found that GHC systems are 48% more efficient than the best gas furnaces on a source fuel basis, and over 75% more efficient than oil furnaces. 

 Market Potential

The potential for renewable HVAC eclipses the potential for renewable electricity in Maryland and most states. 

  • 65% of the energy consumed by businesses in the Mid-Atlantic region is used to heat and cool their buildings.
  • 62% of the energy consumed by homes in the Mid-Atlantic region is used to heat and cool the housing structures.

A lack of awareness and higher first costs seem to be holding back the GHC industry as of 2013.

 Effective Legislation

To help the State increase its ability to meet its RPS goals, MEA worked with the GHC industry and Maryland’s elected officials to pass HB 1186 on May 22, 2012.  This bill allowed Maryland to become the first state in the country to make the energy generated by GHC technologies eligible for the Renewable Portfolio Standard (RPS) as a Tier 1 renewable source. GHC system owners are also eligible for Renewable Energy Credits (RECs), equivalent to 1 MegaWatt-hour of electricity. 

 To qualify for RECs, the GHC technologies must:

  • Meet ENERGY STAR standards (see Geothermal Heat Pumps Key Product Criteria website for more information),
  • Displace electric or non-natural gas (NG) fossil fuel heating systems
    • 29% of homes in the Mid-Atlantic region use electric/non-NG fossil fuel heating
    • 46% of businesses in the Mid-Atlantic region use electric/non-NG fossil fuel heating
  • Displace old and presumed inefficient air conditioning systems
    • 44% of homes in the Mid-Atlantic region have AC units 10 years+ old
    • 74% of businesses in the Mid-Atlantic region have AC units 10+ years old

RECs from Residential GHC projects can be calculated using the ClimateMaster Savings Calculator.(From this website, click on “Calculate the Savings” in the lower right part of the page.)  RECs from Commercial GHC projects will be determined from technical engineering designs.

To estimate the value of RECs, GHC owners may be interested in the State’s Long-term Electricity  Report for Maryland (December 1, 2011) uses a complex modeling system to predict REC values through 2030.

   Sustainability Frameworks

GHC can be a major contributor to sustainability goals set by established “green building” standards such as the U.S. Green Building Council’s Leadership in Energy and Environmental Design (LEED), Net Zero Energy Homes and Buildings, and the Living Building Challenge. 

One elementary school in Richardville, Kentucky leveraged green design with solar PV and GHC to become the nation’s first Net Zero Energy School, which means that the school generates more energy than it consumes over the course of a year.   

Apply for a Geothermal Heat Pump Grant

Questions

Contact Clean Energy Program Manager Doug Hinrichs via email at dhinrichs@energy.state.md.us or telephone 443-694-1465.