Any Geothermal heat pump owners out here? (Asheville, Hayesville: credit, new house)

[higelj2]

Hello, I see the federal credit on a new installation geothermal unit is 30%, can anybody out there that has recently installed Geo tell me how the North Carolina credit worked for them? I read it is 35% but only to be used against your tax bill or something like that. Wondered how it really worked, considering it on a new house. Thanks, Jeff

[BrianKnight]

Hi Jeff, I dont live with one personally but have installed them in two of our homes. The North Carolina Renewable Energy Tax Credit is the state incentive that covers the credit. Here is a link to an overview on the DSIRE website.

Its actually a 35% credit with an 8400$ cap. The credit is a huge incentive because its money that comes off your total tax liability as opposed to just reducing a percentage of income. I believe there is still a 30% Federal credit in place too. This basically means the government or (us tax payers) will pay for 65% of your heating and cooling system.

Keep in mind that even with the credit there could be better cost-effective measures you could take to reduce your energy costs, namely creating an Airtight and Continuously Insulated building envelope.

Ground Source Heat Pumps tend to make the most financial sense in very large and poorly built homes (in terms of efficiency). That being said, they can be one of the best and most efficient forms of heating and cooling in our climate, if they use the right equipment, and are installed and commissioned properly.

I have a blog entry on Ground Source, Geothermal Heat Pumps in Asheville NC that goes into a bit more detail.

Some energy researchers are finding that Ground Source are not performing as advertised. This has mainly to do with the pumping energy that circulates the ground loop fluid which is rarely included in the manufacturers listed COP numbers. I would recommend avoiding open loops and ensuring that the ground loop fluid circulating pump is properly sized and separately monitored for energy use.

[higelj2]

Thanks for the info. I plan on building in the Hayesville,NC area in the next couple of years and have talked to Eco-panels about using sips. Very interested in their sips. Can a GSP be used for radiant in floor heat? just curious if that has been done or not, I have a friend that has radiant floor heat and uses a wood boiler....so I wondered if it could be done with a geothermal heat pump.

[BrianKnight]

Sounds like youve done some great research! I can definitely recommend Eco-Panels. Ive used them on three homes and been involved with two other project's roof systems. They are an excellent company and product. As with most high performance building products though, it all comes down to how things are installed in the field. Choose wisely

Yes Geothermal Heat Pumps can be used for radiant floors. You would need a "water to water" compressor unit instead of the typical "water to air" that most ground source heat pumps use. We almost did that on our current project with Geothermal but decided to stay with forced air.

Coincidentally I also have a blog entry on Asheville Radiant Floors.

Radiant floors are great and one of the more efficient ways to heat. However, financially they can make even less sense than Geothermal/Ground source heat pumps. In our climate, heat pumps are practically mandatory to handle cooling with de-humidification. They can also be used to heat so you are getting heating and cooling with one system. Radiant floors can only heat. So do you really want an entirely different mechanical system just for your heating needs?

Forced Air gets a bad rap from poorly built building envelopes and duct systems. With an Airtight and Continuously insulated building shell combined with a Manual J designed and installed duct system, you can barely feel any air blowing from registers. Homes generally needs ducts anyway to distribute the fresh outdoor air you should be supplying according to ASHRAE 62.2 ventilation standards.

Another big problem with radiant floors in efficient homes is that it can take a long time to adjust interior temperatures.

[higelj2]

Great point on the cooling needs, sounds like radiant is out for me. thanks again for the info and your time. Jeff