Q:
Hi Paul,
Have you been hearing about problems with geothermal systems in the mid-Hudson region? A number of energy and green design consultants have reported a significant number of systems that aren’t working properly, possibly due to design issues. I am therefore recommending that people wait until they’ve really done their homework, have the right technical team, and are sure they want this technology before making decisions. What do you think? There’s a ground-source geothermal HVAC technology called Direct Exchange, or DX, that’s getting a lot of attention in the region. I’ve heard that it’s not allowed in certain places including Connecticut, and several counties in New York, due to groundwater contamination risks. What is DX and is it safe?
—Simon Gruber, consulting partner, Hudson Valley Regional Council A:
Dear Simon,
First step: Find professionals that advise on energy efficiency and reducing energy demand before trying to sell you an expensive system.

David Squires of Oil Free Energy Solutions advises reducing energy needs: “I’m adamant: if a house is air sealed insufficiently, I’m not interested in installing geothermal.”

Seamus O’Shea from Emerald Energy Systems affirms: “Let me help you save money. Whatever is best: wind, solar, geothermal, does not matter.”

Geothermal installations are more complicated than regular HVAC, so choosing installers with references and experience is crucial.

Henry Boyd of Boyd Artesian says, “You should buy a system from someone who installs [it] themselves and services [it] later on.” Importantly, he adds: “To be a well driller you need a state license. To do drilling for geothermal you do not need a license. Now people are buying well rigs and using them for geothermal and there are many problems with potential leakage and faulty installations” (What you’ve heard about DX in Connecticut and New York probably relates to efforts to license geothermal drillers, which Boyd reports is happening.)

There’s debate about DX (sometimes called Direct Expansion) versus Water Loop systems (sometimes called Water Sourced/Based). One essential difference is that DX uses copper pipes containing refrigerant, while water loop uses plastic tubing containing a water glycol mixture.

Regionally, DX wasn’t common until recently. There are those who advocate DX and others who favor water loop. Some experts say DX is less costly to install and uses less electricity to run. Others say DX systems’ copper pipes are prone to leak and the refrigerants are environmentally hazardous.

Installers like Emerald Energy, Oil Free Energy Solutions, and Boyd Artesian are open to working with both systems, although some prefer one system over the other.

Paul Auerbach of TotalGreenUS installs both Water Loop and DX systems. He said Total Green is authorized to install both water loops and DX, but for a number of reasons prefers DX. In fact, Total Green is currently installing a deep well water loop system for a church in West New York, NJ.

Whatever the system, correct sizing and installation are most important, right after making sure your home is uber insulated and energy efficient.

If anyone would like to join the dialog please log onto the Q & A at newyorkhousemagazine.com where you can make comments.

Have a question for Paul? We encourage feedback and dialogue about subjects that appear in this column. E-mail Paul at greenadvocate@scheinmedia.com