Geothermal Heating and Cooling

By Steve Panosian

Every so often I dream about building a new home. Now that it’s spring, and the New Jersey Lotto is over a billion dollars, I’ve been thinking about it again, but in a crazy way. You see, I love where we live. The property is set in the Ramapo Mountains of Northern New Jersey where we enjoy picturesque views, peacefulness, the surrounding nature and fresh air. However, my home is an ecological nightmare which is typical of older constructions and why I would rebuild from the ground up.

Technology Designer features many articles on the subject of sustainable home design, and so I reached out to a couple of people on the subject of what is new in the world of sustainable energy management to provide me with some ideas on how to spend my lotto winnings.

In speaking with Ron Kamen, of EarthKind Energy Consulting, a sustainable energy adoption expert, and Michael Murphy, of Murphy Brothers Contracting who specialize in design, permitting and building processes, my dream home will include the very latest sustainable design recommendations.

Of greatest interest is geothermal heating and cooling solutions because I do not have access to natural gas, and I want to move away from using propane. I am hearing more about the various advances in geothermal technologies aimed at improving efficiency, reducing costs, and expanding its applicability. These advancements are driving the growth of the geothermal energy sector, making it a more competitive and reliable renewable energy choice.

Michael Murphy

Ron Kamen

Steve: If I were to build a new home on my property in Northern New Jersey, what should I consider?

Ron: We should have learned a couple of thousand years ago how structures were oriented for their living situations. The fundamental natural seasonal effects of sun and heating and cooling are important in maximizing solar gain during the Winter, minimizing it during the Summer with some amount of overhangs and shading. Home construction today requires everything to be very tight with good air exchange and the use of the latest insulation products. The idea is not to lose or waste energy, so you are not trying to heat and cool the outside. Today’s window technology offerings address almost every sunlight and climate situation.

For air exchange, some type of energy recovery ventilator is needed to make sure that you get enough fresh air coming in without losing all that energy to the outside. So, orientation, insulation, infiltration and air exchanges are kind of the first things that I think about when we are going into innovative design.

Michael: First of all, you have to look at and try to find a generalization that will fit the climate that your house is in because the climate is unusual in the sense of the cataclysmic shifts between the 50-degree weather that will occur one day and the 30-degree weather the next and these temperature swings are becoming even larger now! This is common in your area, and that wreaks havoc on the material that you build with. Considering the area of the country we live in, we are more eager to embrace energy upgrades and also embrace zero carbon forms of heating and cooling houses.

Steve: What heating and cooling technology should I be looking at?

Ron: So, we touched upon the need for good insulation, good windows, good air circulation with energy recovery, and now we are into the electric and HVAC piece of it. In terms of your cost, the most efficient form of heating and cooling is geothermal. Michael will attest to the fact that its efficiency is 500 percent or better. The reason for that is because you are going down below the frost line (about four or five feet) and at that depth, the temperature is a constant 50 to 55 degrees. Geothermal systems circulate a fluid, and it comes back starting at 50 degrees, so you do not have to do much to cool a place and the same to heat a place, the system makes use of that ambient temperature from the earth.

So, every unit of electricity put into running the geothermal pumps to circulate that fluid, you are getting four or five units of energy heating and cooling out of it. So, the most efficient form of heating and cooling is geothermal, or ground source heat pump.

Installation of this system can be through trenching which is generally cheaper than drilling and least costly in terms of the capital and labor investment to be able to make geothermal happen. Interestingly – if you cannot trench because your yard is on rock – it may be less expensive to drill vertical wells. Another counter-intuitive fact – it is easiest to now drill into rock. The worst ground to dig wells into is sand, as that keeps falling back into the holes. Drilling 500 feet under the footprint of any building will carry the heating, cooling and hot water for up to 25 stories.

Michael: Another factor in rebuilding a home on your property is you can orientate it, so it captures the right arc of the sun. I was involved with geothermal systems installed very early, like 15 years ago, the first job on a house in Scarsdale, New York, although it was a whole house renovation with additions, I was impressed with what was being done with heat pump solutions. We have considerable experience with these heating and cooling systems and the evolution of technology.

 

Steve: What were the early challenges with geothermal systems that have since been addressed?

Ron: The older technology would take water out of an aquifer or out of the water system, and they were called a pump and dump system because it would pump the water, take the heat out of it, and then dump it out. The challenge with that system is issues with the filters from the sediment and scale, and this caused a lot of problems. Filters needed to be changed and if not, it would lead to a system failure.  The advances over the years are closed-loop, the system is pumping and circulating the same fluid and by doing that you do not have those issues of sediment that would cause the degradation problems from pumping and dumping.

Today, a closed-loop geothermal system is now a standard, it is a science.

Steve: For clarity, when opting for a geothermal HVAC system, what does that offset in terms of choice of energy?

Ron: You still need electricity to run it, but you would not need home heating oil, propane or natural gas. The home environment payoff is doing away with all combustible sources – furnace, hot water, and/or a stove. With geothermal, you can eliminate a furnace and water heater. However – you would need an induction stove to replace a gas one. And an electric dryer to replace a gas dryer.

If you set it up in the right way, you can cut all your combustion sources. So the passive house and the electrification of structures now means that you can eliminate the combustion which you know is pretty good in terms of carbon monoxide and some other contaminants that you’d normally have in your air supply inside which by the way, when you’re running your gas stove, everybody loves cooking with gas, well, that indoor air quality, unless you have a vent running, is so bad if you were outside it would be illegal.

You can cut that source of pollution as well as potential fire hazards too. This is a great advance.

 

Steve: What energy backup solution would you recommend for a geothermal energy system?

Ron: So, basically, it is where you are getting your electricity. Solar PV taps into the largest nuclear power plant in our solar system. You would then combine solar with some form of battery backup. Batteries are becoming cheaper. They currently can affordably address a period of hours as opposed to a period of days.

For long-term outages and energy independence like you are talking about, then you are going to need a supplemental source besides the solar and batteries to take you through the nights and take you through the longer, colder, darker days of Winter, et cetera. So, either a backup generator that is integrated with it, that is one option, or the real thing that I think is so exciting is that if you have an electric vehicle, you’d normally only be thinking about charging your electric vehicle. But you can also use that as an alternate power source. To give you a sense, a Nissan LEAF or a Ford F-150 has enough power in those batteries to support the average family for somewhere between four days and a week, depending upon your consumption and which vehicle you choose.

So now if you’re looking at where are things going and a good opportunity, it’s solar with a little bit of battery storage and using that as the kind of controller to make sure that your electricity systems are all good and then integrating that with an electric vehicle that can discharge as you need it to be able to provide you backup power.

Cool stuff, right?

Michael: With or without solar and backup, you can also have an integrated cogeneration system that would be used for heavy thermal loads. Factoring a large home with a pool, hot tub, a half dozen bathrooms, and the ability to have parties and entertain without interruption, you are not going to achieve all that with geothermal. Cogeneration is a highly efficient process that uses combustible fuel to generate two types of energy, electrical and thermal. By capturing and using heat that would otherwise go to waste, cogeneration reduces the overall fuel consumed in the process. It is one of the cleaner and most cost-effective options available for energy production.

Ron: Cogeneration combines heat and power and can provide an alternate source of electricity as well as heating that is much more efficient than just a gas furnace. It is another technology to think about, especially when dealing with heavy thermal loads.

Michael: You know what’s interesting when you look at it, the younger architects, they’re coming out of colleges today being trained on this technology and many are becoming aggressive to the point where they want to see the chain of custody of materials that are used in the project to make sure that the carbon footprint attached to the certain products isn’t going to be detrimental to the planet.

On the other hand, though, you have AI which in my estimation could end the need for an architect, and in the snap of a finger, you can do a hybrid between a Frank Lloyd Wright and Mies van der Rohe type of house. While this may be 10 years out, what AI is doing is it is moving exponentially. The move towards things being built in a factory and then assembled on the site using panelized systems and just basically buttoned all together, they’ll already have included the geothermal system.

Steve: What challenges do developers have in keeping up with changing technology?

Michael: One of the things that concern me, and I think Ron will even attest to this is that we need to expand our experienced installers and maintenance crews that can take care of this equipment because no matter what you have installed, just like your gas furnace or whatever you have, it has to be maintained. You have to have it looked at every year or maybe twice a year. You need to know the heating and cooling systems are running correctly and everything’s okay, we are woefully lacking enough trained and skilled professionals to install and support the new geothermal, solar and cogeneration systems.

It is not easy to find somebody that does a respectable job of installing geothermal and it is part of offering maintenance that goes along with it on a year-to-year basis. For a young person, it is a worthwhile investment of their time. Becoming an electrician and understanding these advanced technologies and installation can turn into starting a business.

On the other hand, people who have been doing HVAC work for a while are recognizing that they need to keep upgrading their technology, experience and training. Air conditioners are heat pumps. An air conditioner or an air source heat pump that also produces heat or a ground source heat pump, it is still basically a heat pump. So, it’s not necessarily the technology that is continuing to advance, it’s much more computer-oriented than it used to be, but it’s not as great a leap as people would think, and if you’re used to working on air conditioners, you can work on heat pumps, whether it’s an air or ground source pump.

 

Steve: Anything else you would like to share?

Ron: Heat pumps are going to continue to expand. Two years ago, air source heat pump sales started exceeding furnace sales on an annual basis in the United States, and the trend is up. With this demand trend and everything that goes into that too, everybody needs to be somewhat familiar with computers and computer controls.

There are two principal areas I see continuing to expand, controls and the electrical infrastructure. So, electricians, HVAC guys dealing with heat pumps, and then everybody dealing with computer tech is my thought.

Michael: My suggestion to them would be that there is so much information in various fields from the insulation side to the energy side to the construction side, to the sighting of the problem, my suggestion to these individuals would be that they should develop a group within their group. A group of experts that they meet with whom they can share information with people that they rely upon.

For instance, Ron came in as Murphy Brothers’ clean energy consultant. Whenever we have a project where we always pitch clean energy, we bring Ron in on it. We consider Ron part of this group of experts, my small cadre, that I can count on whether it is land use, clean energy, electricity, plumbing anything my circle I learned from and I can share.

If they are not already doing something like this, I would suggest that they start their circle of collaborative partners they meet with whom they can rely upon. The pace of change dictates because again, things are changing rapidly.

The energy movement has changed everything, think about it, the simplest thing like flushing a toilet when we were kids, three and a half gallons of water go down the drain and today, it is less than a gallon and it works well because modern technology fixed it to work that way. Minimizing wasting water, making the best use of energy by moving away from combustible sources, and overall lowering our carbon footprint are the design objectives.

Everything must work more efficiently because we are moving to an electrical-based future.

 

 

Steve Panosian is a Senior Editor for Technology Designer Magazine and Technology Insider Group. He is an independent consumer technology industry consultant specializing in the CE Home Theater and Custom Installation (CI) market withover 40 years of experience in retail sales and various manufacturing roles.