Geothermal heat is both ancient, in terms of its origin, and cutting edge, in terms of its application today to home heating. Simply put, geothermal heat pumps use the heat that is naturally stored in the earth itself to regulate the temperature of a home or building, without relying on combustion from either gas or oil. Here is an overview of the pros and cons of geothermal heat pumps.
Geothermal heat pumps are suitable for small homes and large commercial spaces, with many benefits including cost and energy savings, as well as aesthetics.
- Environmentally friendly
Geothermal heat pumps are highly efficient (300-500% vs. 90% for the best furnaces) and use energy from a renewable resource.
- Cost effective
Because there is no oil or gas to purchase, geothermal heat pumps aren’t subject to the cost fluctuations from gas or oil prices. In addition, the efficiency of these systems results in 30-60% savings on heating and 25-50% savings on cooling.
- Quieter operation and minimal footprint
With no visible outdoor compressor or fan, geothermal heat pumps are quieter to operate. A loop system of pipes buried underground draws heat from the earth into the home, or releases heat from the home back into the earth.
- Not weather dependent
Unlike solar or wind, access to this type of energy is not dependent on weather, and doesn’t change throughout the year.
- Eligible for tax credits
Federal tax incentives, as well as assistance in the form of low interest loans from some utility companies, are available.
- Long lifespan and minimal maintenance issues
Indoor components last up to 25 years, and the outdoor underground loop system lasts 50 or more years, making it an investment that can pay off for generations.
- Technology behind geothermal energy will only continue to improve in efficiency
While there is much in favor of geothermal pumps, there are also some downsides to consider.
- High upfront costs
Geothermal heat pumps can cost as much as $10,000-$20,000 to install, depending on how easy it is to bury the pipes and how big the system needs to be. Keep in mind, however, that due to the substantial energy savings, the time required to recoup that initial investment is very short.
- More suitable for new home builds
Because installation can involve large scale excavation, retrofitting is more disruptive and potentially less cost effective than incorporating geothermal into a new home at the time of construction.
- Electricity is still needed to operate heat pumps
While no oil or natural gas are required for operation, electricity is still used.
- Geothermal energy using wells has certain negative ramifications
A system requiring the use of a well may be impractical in some areas where water is scarce and/or expensive because it requires a large amount of water to operate. In addition, this type of geothermal system my discharge sulfur dioxide and silica into the earth.
- Damage to underground loops can be difficult and costly to repair
Tree roots, the water table, rodents, etc. can cause damage to the parts of the system that are buried and difficult to access. Fewer technicians are available for geothermal systems than for traditional systems, so service may be more expensive.