Conversation & E-mails with an Engineer about Geo Heat Pumps February 02 2018, 2 Comments

I had occasion to speak about renewable heating with a community leader after a regular monthly police precinct meeting.

We talked generally about climate change and both stated our opposition to fracking. Then I said the next big thing coming down the road is a statewide push for non-fossil-fuel heating with geothermal heat pumps. He said he understood the geothermal ground loop brought 55 degree water into the house, but he didn’t get how that could heat a home.

I asked him if he knew how a heat pump worked. He said yes, he was an engineer. He interrupted several times as I explained how a refrigerator, one example of a heat pump, moved warm air out of the ice box and into the air in the kitchen. Had he noticed the heat around the refrigerant coils? Not really. However, that's how a geothermal heat pump works: it extracts the heat from the loop fluid, amplifies it and then sends it into the air handler.

He still didn't get it, so he asked me to send him some links to websites that explain it. I sent him an email titled "How heat pumps generate heat" attached with a PDF excerpted from the NYSERDA engineers and architects geothermal heat pump training given by my friend Jay Egg. I also sent him these links that I checked out to make sure they were pertinent:

How-the-Heck-Does-a-Heat-Pump-Get-Heat-from-Cold

heat-pumps-work-cold-weather/.

Both articles explain how heat pumps work, but are focused on air source heat pumps. I told him geothermal heat pumps start with lower temperatures in the summer (and higher ones in the winter) and don't require a defrost cycle, so they are more efficient.

I also sent him a link to the NY-GEO website and asked him to let me know what he thought.

His response was interesting, so I will quote it verbatim:

I understand you are promoting non-fossil fuel heating systems.

While I think that is a noble cause, I believe it is disingenuous because of the electric heating coil back up. Most heat pump systems are useless below 20 degrees, even with new LEED construction. Plus, unless you are replacing an existing cooling system, there really is no benefit. I have no central air in my home.

The recent sub-freezing temperatures proved heat pumps are not the most economical heating method here on Long Island. Anyone who has them dreads very cold weather.

Solar panels are a mature, proven technology. Unfortunately they are still rather expensive, and I would not install them unless I get 100% of the savings.

Since most heat pump systems require duct work, my home would not be a good candidate.
When new home [sic] are built here on Long Island, the main selling point is gas heat. Yes, I know where natural gas comes from.

Oil has it's [sic] issue with storage, as the cold weather also affected outdoor tanks. And delivery during snow storms. Upstate, the fuel of choice for heating is propane. It does not coagulate in sub-freezing temperatures.
I have a very unique system. I have gas steam heat that does not require ANY electric hook up. I have heat and hot water with a power outage. Not very common today. Plus, I also have a gas stove, gas dryer and a natural gas BBQ.

There is no simple, easy answer. What I DO know is that here on Long Island, we get our electric supply from #6 high sulpher [sic] oil fired power plants, plus a smattering of natural gas turbines. Not very eco-friendly.

Block Island now gets 100% of it's electric from windmills.

2/3rds of Con Ed's power for all of New York City comes from unit 2 and 3 of Indian Point nuclear. Unit one has been expired for some time. Two and Three are not too far behind. I am not a fan of generating power from using a nuclear power plant to make steam.

Many coal fired plants are being retired around the country. You and I both know there is no such thing as "clean coal".

Northport plant is now over 60 years old. They won't upgrade it without a certiari. They want a 50% reduction in their property taxes, to be initiated over a 10 year period. Both the Town and the Northport school district have it in litigation. They will lose. And we, the ratepayers will foot the bill. Google "Stony Point power plant" to see what happened to last coal fired plant in New York State.

If transmission lines were added from Canada, Hydro Quebec would sell us plenty of electricity. Marcy South is not enough. Plus, PSEG does not get many credits from PASNY.

In short, here on Long Island, there are no easy answers to electricity generation, or heating homes. I believe natural gas is our best fuel of choice until a new technology comes along.

Perhaps we will see new technologies in the near future...

Doing some research, I find this:

Hi [Name withheld],

The second most asked question we get from homeowners after "will I really save money?" is "how much does it cost to install?".

Today I'm going to give you the quick breakdown on how much central ducted heat pumps cost.

There are two types of machines.

Add on heat pumps that work in line with your current furnace as a backup

Full replacement heat pumps which replace your current hot air furnace entirely with electric backup

The add on machines are less expensive and are popular with home owners who's [sic] furnace is reasonably new or still in good shape.

Cost for an add on machine ranges from $9,000 to $12,500

Why the range? Because there are different sized units as well as different levels of efficiency. We sell York and Daikin central ducted heat pumps. Both offer a good, better and best option which falls somewhere in that price range.

Cost for a full replacement heat pump is $10,500 to $13,000

A note about full replacement heat pump. In some cases your home may also require an electrical service upgrade. This is something that would be determined with an in-home visit from one of our representatives. The upgrade can be done by our electricians and built into the one invoice.

Financing the Purchase of your Heat Pump

Something not known by all home owners is you can financing [sic] the purchase and install of a new heat pump for up to 10 years with Nova Scotia Power. We have a detailed article on the program at our website. Click here to learn more about how you can finance a heat pump.

It was clear from this reply that he hadn't bothered to look at the PDF or links I so painstakingly vetted for him. Despite the subject of our discussion being geothermal heat pumps, he simply based his opinion on a letter from someone selling air source heat pumps. Perhaps this was the person he contacted before he chose his current heating system.

I was nonplussed by my acquaintance's response. He seemed to ask questions, but then not listen to the answers. I debated whether to continue the conversation. After two weeks or so, I wrote this reply:

Hi [Name withheld],

Sorry you didn't take a good look at the links I sent.

You write "The recent sub-freezing temperatures proved heat pumps are not the most economical heating method here on Long Island. Anyone who has them dreads very cold weather."

Who have you talked with on Long Island? The letter from [Name withheld] does not address geothermal heat pumps (GHPs). Daikin and York manufacture only air source heat pumps, NOT geothermal.

With all this topsy-turvy, deep-dive temperature weather this winter my geothermal heat pump has been working great! This is why I promote them: I've enjoyed one for almost seven years. People I've referred love theirs. So do Canadians.

Here are the two significant differences between air source and geothermal. Air source heat pumps:

  1. rely on outside ambient heat (which, in winter, is colder than that underground) and
  2. require a defrost cycle to keep the outdoor coils from freezing and shutting the system down. That happened to me once when I was staying with friends who had air source. (They had to call a technician to come to thaw out the coil.)
GHPs rely on underground heat that stays relatively constant at 52-57 degrees on Long Island (according to the EPA, see attached map). There is also no need for a defrost cycle since the geothermal heat pump is inside the building.


Hope this clarifies things.

PS I have too much integrity to promote a product I don't find economical or practical.

I have not heard back from him.