Geothermal heating and cooling relies on the natural, stable temperature of the earth and water under the earth. Though it can be costly to build, it can be a renewable resource, sustainable, and green.
Over time, it can also save homeowners money that they would normally spend on air conditioning and heating.
How Does Geothermal Heating & Cooling Work?
Geothermal heating and cooling doesn’t work like traditional furnaces. Where a traditional furnace burns fuel such as natural gas, wood pellets, or logs to bring in heat, a geothermal heat pump works by bringing in heat from the ground.
Just a few feet below the soil, the earth maintains a constant temperature of around 50 to 60 degrees Fahrenheit, all year round. Since it is consistent, it can be used as an effective way to heat a home.
Fluid-filled pipes are installed several feet below the soil. These pipes absorb the warmth from the nearby earth and move it into the home. There is a pump that moves the water around.
So the water will be heated by the earth, and then moved into the home where it releases the heat to the colder air. Then, the now-cold water moves back to the earth where it can absorb more heat.
In the summer, this reverses. The home is much hotter than the earth, so the water absorbs the heat from the air in the home and gets transferred to the soil.
Sometimes, the pipes are underwater instead of under the soil, but the process remains the same. Depending on the method and your location, the heating in those pipes can stay anywhere between 45 and 75 degrees.
That doesn’t mean that your home is going to be a brisk 45 with geothermal. That just provides the base heat to help reduce some of the work.
If the temperature isn’t warm enough as is, the water is vaporized before being allowed to cool back down into a liquid. That heat is then filtered through your home until it is at the temperature you wanted.
This helps you to save on electricity because there is already a base temperature to get you started. Instead of heating cold air in your home, it takes somewhat warm water and warms it up more.
Also, water is easier to heat up and cool down than air, making it a more effective way to warm up an entire home quickly. This is similar to heated floors that use water, or radiators in other countries where they pump water through hot metal.
How Much Can You Save With Geothermal?
Since there isn’t as much heat lost, and less work has to be done in heating your home, you have the potential to save a lot of money. Though installation is costly, you do get a tax credit.
This credit is anywhere between 22% to 26% of the installation cost. Sometimes, you can also get rebates or credits on your monthly utility bills, depending on where you live.
But that isn’t all that you save with this process. Geothermal heating and cooling systems are around 400% efficient. This means that, generally, for every unit of energy you put into the system, you get about 4 units of energy back.
Even high-efficiency furnaces are only about 98% effective. This means you are easily getting four times the power with the same amount of energy.
This roughly translates to about 72% savings compared to a furnace or AC unit and about 44% savings compared to air-source heating and cooling systems. Per year, this can save you about $2,200 and about $52,800 over its lifetime.
This means it takes about 7 to 10 years to recover the amount you invested. The rest after that is pure savings. Usually, with proper maintenance, the pump can last about 2 decades, but the pipes will last much longer [usually around 50 years], so your replacements could be far less costly in the future.
Who Should Consider a Geothermal System?
There are many benefits to using a geothermal system, but that doesn’t mean it works for everyone. There are times when there are cheaper and more effective options.
For example, if your home is improperly insulated, spending that money, or a chunk of that money on insulation, can easily save you 70% or 80% in energy bills, which is more effective than getting geothermal energy and solves the base problem.
Generally, the smaller the home, the fewer savings you are getting from geothermal, and the longer it takes to get your money back.
While it is a great idea, it is still too costly for many people. Plus, there are many factors that one must consider when getting geothermal, including whether you can install one in your area.
Some places don’t allow for geothermal or digging in areas, and you have to make sure there are no pipes or lines that can be damaged by the installation of these pipes.
However, this method works well for larger buildings. For example, if you own an apartment complex or a multi-family home, then geothermal can save a lot of money on heating and cooling. It can also help with places like schools and churches.
If you have a larger home or have a lot of money you can afford to spend on this system, then it may be worth it. Additionally, if you are a person that likes very hot or cold temperatures, geothermal heating and cooling is a great way for you to get the temperatures you want and save a lot of money throughout the year.
Finally, people that are planning on selling their homes at some point soon can also benefit from these systems. There is about 12% annual growth in geothermal heating and cooling, so they can boost your home sales.
What Affects the Cost of Geothermal Heating Installation?
There is a wide price range for the average geothermal heating and cooling system. Most averages call for anywhere between $25,000 to $60,000, but some say it can be much higher.
This is because there are a lot of factors that change the cost of geothermal heating and cooling installation.
- System Size – Heating pumps can only hold so much. Depending on the size and efficiency you want, you may have to get a larger or smaller pump.
- Loop Direction – You can get either a vertical or horizontal loop. Horizontal is usually the cheapest as you do not go straight down. However, you must have the space for this, or you will have to go vertical, which can be very costly.
- Brand – As with any product, different brands cost different amounts. A lot of the time, installers will only work with certain brands, which can up your total cost.
- Labor – Every company charges different costs for labor. Depending on the company, you may have to pay more than you expect. However, a higher cost often comes with more experience and skill, so don’t go for the cheapest option automatically.
- Location – different locations can change costs based on what is available.
- Soil Type – Depending on the type of soil, the ground may be easier or harder to dig into, costing more labor.
What Affects the Cost of Geothermal Heating Installation?
According to research, the average cost of installing a heat pump is about $25,000. However, since the factors are so variable, it is just a rough estimation, and there is a wide range of costs.
On average, you can expect to pay anywhere between $10,000 to $40,000. However, a lot of people have said that these are generous estimations, and most systems cost closer to $50,000.
What Are the Parts of a Geothermal System?
There are two types of geothermal loops. These are either vertical or horizontal. As the names suggest, one runs along the level ground a few feet under the soil, while the other goes straight down under the earth.
The horizontal one is often cheaper as they don’t have to dig so far down. These can be in the soil, or water, depending on what you have around you. Usually, they are pipes made out of plastic tubing and are filled with a mix of water and antifreeze.
Geothermal Heat Pump
The heat pump is the key part of the system. It has a compressor and a heat exchanger, allowing the system to take advantage of the constant temperature and heat the water running through the system.
The heat pump is what allows for the movement of the water through the system for heating or cooling.
The distribution system is what spreads the heat throughout your home. There are two methods, which are the forced-air system and the water-to-water system. The water-to-water is often what is used to heat flooring, as the heat is kept in the pipes which slowly release heat to the ground.
Forced-air systems transfer heat via air and ducts to move the hot air around your home after it has been heated by the water.
Open-Loop vs. Closed-Loop Systems
The last part of the system is open vs closed-loop systems. These are the two types of systems you can get.
Closed systems are made up of the water mixture in the system. They take heat from the ground and bring it inside the home or building. They can be vertical or horizontal and in water or soil.
Open-looped systems take groundwater through the pipes instead of the water mixture. These have to be installed in water or at least be able to take in groundwater.
The main difference between them is that the closed system will use the same water mixture over and over again while the open-loop system uses it once and then dumps the water into a nearby sink, like ditches or ponds.
Open loops are generally cheaper but need a constant source of water that is clean and fresh. Generally, closed-loop systems last longer and have no impact on the environment as they do not draw in or release anything.
Sometimes, open loops cannot be installed in areas due to the potential damage and the fact that they can take water away from local resources.
What are the benefits of geothermal heating and cooling?
Some benefits of geothermal heating and cooling are:
– They are 400% efficient
– Better for the environment
– Last a long time, about 25 to 50 years at a minimum
– Quiet since there are no large and loud outdoor units
– Safe as there is no combustion involved
– Provide heat and hot water
– Air isn’t recycled so you get cleaner air quality
What are the drawbacks of geothermal heating and cooling?
Some disadvantages are:
– The initial cost is high
– It may not be available to everyone who owns a home
– No one who is renting can use them
– May have to pay extra to install ductwork
– You have to find a contractor who knows these systems
– Some communities don’t allow these systems, no matter what kind
– The installation will require your yard to be ripped up, which isn’t great if you have done landscaping or have a pet
How long does it take to install geothermal heating and cooling?
Depending on the weather, ease of installation, and what all needs to be included, such as ductwork, you can expect an average of 6 to 8 weeks, but a longer time is also common due to delays and permit issues.
How long does a geothermal heating and cooling system last?
Often, with good care, your heating pump can last about 25 years before needing to be replaced. However, the whole system can last up to 50 years without a problem if taken care of properly. Some may even last longer.
Open-loop systems may have to be replaced more often as they can get sediment inside of them, which damages the pump and pipes. These may last closer to 25 years in total.
What are the maintenance requirements for geothermal heating and cooling?
There are a few basic steps you have to do to maintain your heating and cooling systems. These are:
– Keep an eye out for leaks
– Clean and check leaks in your ductwork
– Have your system cleaned by a professional occasionally
– Check the antifreeze occasionally
While you can keep an eye out for anything out of the ordinary, a regular maintenance check will cover all of these problems for you.
What are the most common problems with geothermal heating and cooling?
There can be some big and some basic problems with a geothermal heating and cooling system, the same as with any other system. These include:
– Dirty air filters
– Issues with the pump such as blocked pipes, leaks, and broken fans
– A busted or bad pump
– Irregular pressure in the loop