Is Geothermal a Realistic Way to Achieve True Energy Independence? by Sallie McBrien

Energy independence is a goal for many households and communities for a variety of reasons from simply wanting to save money each month, to the broader goal of saving the planet for future generations. To accomplish this lofty goal, there must be a way to generate energy independently of any centralized source (e.g. solar, wind, etc). For example, a successful home solar system can meet most of a home's energy needs if the system is well-placed and in direct sunlight for a large portion of the day. However, even in some of the best situations, there's likely to be some time when the house must run on power from a utility company. For a homeowner who wants to be energy independent, this can be discouraging—but it does not mean this goal is impossible. With this in mind, many seek energy-efficient home improvements in conjunction with their energy-producing improvements.

In most situations, air conditioning and heating use the most energy of all appliances in the home. Small improvements can certainly add up over time, but it may be difficult to achieve year-round energy independence if these main culprits aren't addressed. Although it may not be considered "mainstream", geothermal HVAC systems present an interesting solution to this issue.

Significantly Decreasing Home Energy Demand With Geothermal

Traditional HVAC systems account for almost half of all home energy use. HVAC energy usage is especially high in summer, when the air conditioner uses between 3,000 and 5,000 watts of energy per hour. How much energy per hour is determined by the age and size of the air conditioner. Older air conditioners tend to be more energy inefficient, both because the energy efficiency of air conditioners has been improving with time, and also because air conditioners lose efficiency as they age.

How often the air conditioner runs throughout the day depends on many other factors, including the size of the house, insulation, weather stripping, condition of the ducts, how much the homeowner runs the air conditioner, and so on. All in all, if the house is quite large and the insulation quite poor, this could amount to 28,000 watts of power each day. Even in the most optimal situations, heating and cooling can use a significant amount of energy.

Homeowners who want to reduce their home's energy usage so they can live more "off the grid" can do so by installing an energy efficient HVAC unit. However, those who aspire to go completely independent might look at a less "traditional" HVAC unit. According to the U.S. Department of Energy, geothermal units can cut a home's energy usage by as much as 65%. This enables homeowners to maintain a comfortable temperature indoors even while they remain reliant on their solar panels or other renewable-energy-generating systems.

Geothermal heating and cooling systems do not actually generate hot or cool air—or at least, not directly. Simply put, they act as a means of transportation for the constant temperatures underneath the earth. As such, the amount of energy needed to operate this kind of system is relatively minimal.

Longevity and Value

In addition to the energy efficiency of geothermal heat pumps, there are many other benefits for people that adopt this technology. Those who are looking to help the environment will want to ensure they are not contributing to unnecessary waste, and those who are looking for an economical choice will want to come out ahead financially in the long run. Luckily, both of these goals are met by geothermal HVAC systems. Geothermal heat pumps consist of two components: coils in the ground and the heat pump itself. The coils in the ground can last up to 50 years, and the heat pump can last as long as 25. Homeowners seeking a long-term investment can find what they're looking for in geothermal units while reducing their contribution to landfills. The effectiveness, longevity, and durability of these systems makes them very attractive to home buyers when the time comes to sell a house. This can increase the home's value in addition to reducing monthly bills. Geothermal heat pumps also help communities overall reduce their dependence on the electrical grid.

If you're a homeowner who would like to live energy-independently, now is the time to think about what you can do to reduce your dependence on the electrical grid. Replacing your home's HVAC system with a geothermal unit may be one of the most effective ways that you can make this happen. To find out more about how you can have a geothermal HVAC system installed in your home, contact a reputable HVAC contractor today.

Sallie McBrien is a REALTOR® with Your at Home Team, helping buyers and sellers in the Alexandria, VA area. She specializes in helping service members with relocation.

To find out how AI can make geothermal heat pumps even more effective, see the DOE announcement here.

Views: 204


You need to be a member of Home Energy Pros Forum to add comments!

Join Home Energy Pros Forum

Comment by Richard C. MacCrea on May 29, 2019 at 11:38am

We find it best to focus on cost versus return. What is the cheapest, most reliable way to save the most energy? Each house, client, and site is unique. This means each solution will be different. But we find the best solutions are usually in this order:

1. Solar orientation: If the home is about to be built or remodeled, changing the windows and roof overhang can save a LOT of energy without raising cost. 

2. Improve the envelope: Better insulation and air barriers can save a lot of energy with a small cost increase. 

3. Improve the design. Plan for more efficient function of the house systems, like placing the entire HVAC system inside the insulation envelope, shorter duct runs with fewer turns, shorter hot water pipes, etc. We also look at reducing wasted space. This step can reduce construction costs. 

4. More efficient appliances: By this time so much reduction in heating and cooling costs has been made that an expensive upgrade to the HVAC system would probably not be worth it. We usually consider a Marathon water heater, induction stove, and a convection microwave in place of a conventional oven, all for a small increase in cost.

5. Now the home is so much more efficient that it would require a much smaller solar panel system to reach net zero. These principles could help many more people afford a net zero home. 

Let's all stop thinking about a single favorite idea for saving energy, and start thinking about what choices are best for each client, site, and budget. 

Richard MacCrea

Comment by Chris Heenan on May 21, 2019 at 12:27pm

Article written by a Realtor.

WSHP have very high efficiency but

they significant install _and_ repair costs down the road.

Medium grade efficiency equipment returns investment which a WSHP may never. IF it would last 25 years then maybe you're getting closer to break even.

But companies that service higher end equipment will have higher repair costs to the homeowners.

As a state licensed HVAC contractor, I can put a WSHP in myself but there's not interest even at my own house simply for the reasons above.

Comment by Ed Minch on May 16, 2019 at 3:43pm

Some passive houses find that resistance electric heat is cost effective.  Put your money into a better envelope and you won't need better equipment

Comment by tedkidd on May 16, 2019 at 10:20am

Just put in high end air source, put some of the savings into fixing the envelope, and use the rest for a down payment on an EV &/or Solar.

Maybe not as much bragging rights at cocktail parties, but much more significant impact.


Latest Activity

Robin Henry posted a discussion

Most current can light air sealing best practices?

I haven't had to airseal any can lights in several years. I have a client who has many can lights…See More
Building Performance Association posted a blog post

August Policy & Advocacy Updates

By: Lizzie Bunnen, Government Affairs Director, AnnDyl Policy Group…See More
Building Performance Association commented on Emily Ambrose's blog post 6 Building Conferences We’re Attending
"Great picks! Thanks for including us!"
Building Performance Association liked Emily Ambrose's blog post 6 Building Conferences We’re Attending
Diane Chojnowski's 2 videos were featured
Brad Cook replied to Chris Stratton's discussion Okay to use 1" polyiso as a insulation base for 50 gallon heat pump water heater?
"Not all insulation is the same. For example, Dow's Super Tuf-R polyiso has a compression…"
David Butler replied to David Wentling's discussion ERV recommendations
"@Luke, since you work for a well-known ERV manufacturer, I'm curious if you have access to…"
Luke Langhals replied to David Wentling's discussion ERV recommendations
"Hello David -- Do you have an expected air tightness? What type of blower door test results are you…"

© 2019   Created by Building Performance Association   Powered by

Badges  |  Report an Issue  |  Terms of Service