Geothermal: An Understated Idea Whose Time Has Come
There are two things that have become a common theme when folks first learn about geothermal systems. First, most are amazed that there are so many of them, often nearby; and second, that there are so many different types of geothermal coupling methods. I’ve had a tremendous opportunity in recent years to share information about geothermal systems with rooms full of architects, engineers, geologists and drilling professionals.
The lack of knowledge stems from lack of educational sharing of the technology. Sure, the information is out there if you do your research, but it’s sometimes difficult to get a real idea of geothermal HVAC technology in a holistic way. As an example, I was recently on a conference call with several experts in New York. While there were geologists and engineers on the call, they were mostly concerned with the disconnect between the building system and the ground-coupled portion. Few people seem to get the whole picture.
Fundamentally, a geothermal system consists of either a central chiller plant, or distributed water source heat pumps that are connected to a geothermal exchanger or some type of earth coupling. The geothermal exchanger serves to eliminate the boiler and the cooling tower, which means essentially all of the outside equipment. Also gone are the emissions associated with combustion boilers, and the legionella concerns, water consumption, and high service and maintenance costs of a cooling tower.
I’ve found time and again that one hour is not enough to share this concept. One-hour talks and presentations pique interest, but are often forgotten as attendees head out to the next class or presentation. Six to eight hours are just enough that folks become fully converted, especially if they are attending a CEU/PDH or AIA class they’ve paid for. At that point, it really sticks.
There has been so much success with this concept that New York, Ontario and the International Ground Source Heat Pump Association (IGSHPA) have adopted a fully vetted curriculum for professionals that is designed to teach the “gospel” of geothermal technology in such a way that they understand they don’t need to be a certified expert to be a specifier of geothermal HVAC systems. With few exceptions, when these professionals leave a presentation, they’re excited and ready to specify geothermal on all projects moving forward.
The analogy is simple. Take our smartphones as an example. I don’t have to know how a smartphone works to be an expert at using it to make me successful in my business. The same analogy applies to an earth-coupled home, building, community or city. If it is specified as a geothermal exchange system, it can and will be done if the technology is applied properly.
Just to solidify the validity of this claim, consider that Stockholm, Sweden, has operated on a central surface water geothermal exchange system since 1988 (30-plus years). Or, that in the city of Hamilton, Ontario, a District Energy System provides thermal energy in the form of hot and chilled water to buildings in the downtown core and is connected to a geo-exchange field. Ball State University in Indiana converted over from a coal-fired boiler to 100-percent geothermal-sourced heating and cooling in a period of just seven years, using 3,600 boreholes. That’s a lot of drilling, but it has replaced the need for cooling towers and boilers permanently.
What is surprising is just how many systems there are currently. Though nationally the percentage is not that high, in every properly applied situation, geothermal has been successful. As I’ve traveled throughout cities in New York and Ontario over the last year, I’ve found countless decades-old geothermal systems that have operated quietly and out of the public eye. In the city of Sault Ste. Marie (I learned to say, “Soo-Saint-Mah-Ree”), Ontario, we even found out that the very building in which we were meeting, the multi-story civic center, had been operating as a “surface water geothermal system” since 1973.
In New York, the state and local jurisdictions have a mandate to reduce greenhouse-gas (GHG) emissions 80 percent by 2050, and they must change combustion heating appliances and furnaces to heat pumps to attain this goal. Government officials have stated that they can’t afford or allow any gas furnace to be replaced in kind, because they will lose that GHG reduction for another 10 to 15 years.
I’m going to share just how many systems are installed along the coast in Miami. Not by number, but in an image from a map (Florida Department of Environmental Protection) on the next page that shows the location of geothermal injection wells. In hot and humid climates that have good aquifers, most geothermal exchange systems use Class V UIC injection wells to return geothermal aquifer water back to its source after making a quick trip through the hydronic circuit of the building that it’s serving.
If you zoomed into the image, you could see that many of the structures are government owned, while others are privately owned high-rises. Applied Drilling Engineering Inc., of Florida, has experience with these systems. They have only recently gone from a reactive stance to a more proactive state, working with local mechanical, electrical and plumbing (MEP) engineers and construction folks. The result has been serious growth and a new focus. Stuart Anderson and Paul Petrey of Applied Drilling Engineering say that there’s enough geothermal drilling work in Florida to keep them (and every other driller) quite busy for the next 30 to 40 years.
In Florida, local geothermal advocates are working with water authorities, which are impressed by the tremendous water savings made possible through geothermal-sourced HVAC. I had a chance to speak with Anderson and Petrey when they attended the IGSHPA conference in Orlando, Fla., last April.
One of the main focuses they spoke of was the extraordinary need to save water. Many people don’t realize that commercial cooling towers are the second largest consumer of water in commercial buildings nationwide. Petrey shared with me that, in all of his time working with water regulating authorities in the past and currently in his position on the Well Drillers Advisory Committee (WDAC) for the Southwest Florida Water Management District, one lesson learned is that any “water saved equals new water.”
This may seem counterintuitive, considering Florida seems to be a sandbar between the Gulf of Mexico and the Atlantic Ocean. Florida’s aquifers are generally very prolific, but over-pumping has caused issues with water quality. You can be certain that water savings in other areas of the U.S. and the world are of equal importance, if not greater.
Both Petrey and Anderson cut their teeth in the petroleum industry, 35 and 41 years ago respectively. Petrey jumped into the water-well business in 2000, and Anderson became a licensed driller in 1987. They drilled their first well for a geothermal HVAC system in 2013. That particular project was for a homeowners association in Siesta Key, Fla. The customer needed a deep return well to improve the separation from the existing HVAC supply wells. That project ended up with a total open-hole depth of 1,463 feet.
They’re just finishing up on a project for the Pinellas County Safety Complex, which adds capacity to an already robust geothermal HVAC system there. That complex is a mission-critical 911 call center and police station. They chose geothermal for their new build in 2012, because they can’t afford to be out of business. Several other projects are on the books, and they are expanding to handle the volume.
If you are not already involved in geothermal HVAC drilling, take a bit of time and look into it wherever you are located. Go to the IGSHPA site and take a class for CEU credits. This technology is increasing every year, and it’s become the way to save water, provide permanent infrastructure, and eliminate cooling towers and boilers from buildings. Geothermal is where you want to be!
So, you’re in the driver’s seat on this frontier of green energy. Drillers are the key to pumping unlimited renewable solar-thermal energy from the Earth. It’s a good time to be a driller.