In this episode of Green Talk, Green Building Pro Editor, Mitchell Funk talks with Mark Mizrahi, President and CEO of EnLink Geoenergy. Mark goes over geothermal heating and cooling and its application in the green building industry. Geothermal energy can be harnessed to drastically reduce water and energy use in your project, all powered by the moderate and stable temperature of the Earth. By utilizing geothermal pumps (GHPs), you can tap into one of the most efficient energy sources available. The U.S. Department of Energy estimates that GHP systems can range from 300 to 600 percent efficient, outputting more units of energy than are put in. Mark talks about the range of applications he has seen for the system including schools, commercial buildings, and homes. He concludes with valuable tips for those looking to implement a system in their next project.

Interview Transcript

From Green Building Pro, this is Green Talk.  I'm Mitchell Funk, editor for Green Building Pro, and joining me today is Mark Mizrahi, president and CEO of EnLink Geoenergy.  We're very happy to have you with us today, Mark.

Thank you, Mitchell.   Well, we're here to talk about geothermal heating and cooling.  And I wanted to start off asking just a general question for our audience today.   What is it and how does it work?

Well, geothermal heating and cooling, I like to refer to it as the original renewable.   It's been in place for 50 years, but unfortunately most people haven't heard about it.  Basically what geothermal heating and cooling does, is it harnesses the constant stable temperature of the top 500 feet of the earth's surface to heat and cool your buildings, without the need for chillers or boilers.

Fifty percent of the sun's energy is absorbed by the earth and it is stored in the form of a stable, moderate, constant temperature that's accessible anywhere in the country, any time of year, at the point of us.   And by bearing a series of pipes circulating a refrigerant through them (which is almost always just plain water) into the building, then the heat pumps can take that water that comes in at a stable temperature and make it warmer or cooler as needed.

The same system provides heating and cooling.   Once the system is filled, it consumes no water, there's no fossil fuel, and the electricity used is up to 70% less than a conventional heating and cooling system.   

So it is the most energy-efficient heating and cooling system available.  The other key feature about it is it's a base-load demand application, so it's a peak-shaving, renewable, and it can be used anywhere for any building type.

Well, to me it seems that geothermal heating and cooling is a very versatile technology, and so I wanted to continue with that and ask, Where is it applicable?  And what building systems have or can utilize this technology?

Well, it would apply to the entire building.  So anywhere that you would have a conventional heating and cooling system, you could use geothermal instead.  And it is just...again, we're not generating any kilowatts, we're just working with BTUs.  It's just a heating and cooling application.  So any type of building where you have heating and cooling, you could utilize geothermal heating and cooling instead.

And you would just be heating and cooling your building at up to seventy percent energy savings, compared to a conventional system.   This looks like a very efficient technology.  That's what was running through my head.  And what makes geothermal a smart choice over traditional chiller and boiler HVAC systems that are in place?  

Well, the energy savings certainly, the water savings...In an average size elementary school, a conventional system can consume hundreds of thousands of gallons of water per year.  Geothermal systems consume no water because they're a closed loop system.

Fossil fuel savings, there's no onsite fossil fuel use, no transmission lines of any type, and your maintenance and operating costs go way down because most of the componentry is buried beneath the Earth in the form of pipes, heat pumps and fans which are very easily maintained.

So your operating maintenance cost drops significantly as well.  So over the life cycle of the system, there are immense savings, not only from energy, but again from water maintenance and operations.  

Going off of that I wanted to talk a little bit about EnLink Geoenergy and what you guys are doing.  So I want to ask you a question about the initiatives that you guys are currently doing.

What's the latest and greatest in terms of the projects you guys are involved in?   Well, EnLink is sort of a pioneer in this area.   We've been in the business for over 15 years.   We are a leader in terms of technology development.

We have over thirteen patents that we own or co-own related to both process and products related to this system.

We are a full-service design build contractor, which means we're involved in the early stages of thermo conductivity testing and conceptual development to installation of these systems themselves and everything in between.

So we work closely with energy companies.  We work closely with designers, architects, engineers, building owners, and construction management companies throughout the entire process.

Endlink's focus is on quality systems at a cost-effective price .   And our technology and our expertise allow us to install a higher quality system at a competitive price.   I guess the last question before we go, Mark, for our audience today, if someone was looking into implementing geothermal heating and cooling in their project, what are...what is a tip you can offer them?  

I would say, well, first of all, you want to make sure you're a good candidate for the - I'll probably give more than one tip, if that's okay.   We're going to...First thing is, make sure you're the right candidate for it.  You want to evaluate the economics and make sure it's appropriate for your building type.  

The paybacks can vary and, so you'll want to pay attention to that.   Secondly, you'll want to ensure quality design, so make sure you find a certified geothermal designer who will be a mechanical engineer, but with this specialty.  And you certainly want to make sure you have a top-quality installation that is being drilled properly, grouted properly from the bottom up, and is only using the highest quality materials.

So I'd say those are the three main considerations when evaluating them.

Well, I want to thank you, Mark, for that great interview.  We get a lot of information out of you and we really appreciate it.  I wanted to touch on the fact that we also have an article from you in this month's Green Building Journal, and we very much look forward to reading it.  So, thank you very much for joining us today.

Thank you, Mitchell.  Thank you for your time.

This has been another edition of "Green Talk" by Green Building Pro.  This has been a production of CMC Media.    And for more on this series, please check out GreenBuildingPro.com.