Request: feedback on geothermal and/or solar systems

[Mr Info]

TBDers,

 

Interested in any feedback on geothermal and/or solar systems at your house.

Specifically: installation, ROI/payback, durability, & maintenance.

 

thx

[sherpa]

Glad to.

I've had geothermal and solar hot water, and have built a house expecting to do solar eventually. Not ignorant on the issue.

First, solar.

I don't know how much you know about it, so I will presume you don't know much. Not an insult, just establishing reasoning for what I post.

Solar efficiency is very dependent on the install. Optimally, what you want is total sun access to true south, (not magnetic-I can explain that if you want, but there is a difference), at an angle that is equal to your latitude. So if you are at 36 north latitude, you want your panel installation to reflect that, and aimed at true south. Obviously, no tree or other barriers, especially in the winter when the sun is lower.

If considering, pay close attention to the annual loss of efficiency of solar panels. Not loudly reported, but a serious issue.

Without getting into the details of converting DC from the panels through the battery/inverter process to AC for use, there needs to be a storage capacity and conversion.

In my situation, my garage is oriented true south, at about the exact slope as my latitude, framed for the increased weight of solar panels, connected to the house, and I haven't done it yet because it still isn't competitive with on the grid systems.

In other words, I have the perfect set up for photovoltaics, and haven't done it.

I have a 30x40 barn, and even looking at that, I opted for a gas powered standard generator for power, as I don't use it much.

 

Geothermal. 

I did a geothermal in the last house we built. Great system. By far, the best in the summer with dissipation of humidity, and free hot water, as the fluid goes through the water heater for pre-cooling before it is sent out to the field.

My house was set two-three degrees warmer than my neighbors, but it was far more comfortable, as geothermal really removes moisture.

The issue is the method with which you do the heat exchange, and there are many options. Dirt, ponds, deep wells etc.

The problem is that the method for dealing with that heat exchange has gotten far too expensive, for no apparent reason.

When I did our geothermal in our last house, it was about $5k for an incredibly effective system-five foot deep, packed in rock powder that would guarantee contact and heat exchange.

If you use normal dirt, it will eventually separate from the plumbing with repeated heat/cool cycles..

That's not the total cost, that's the grid plumbing to transfer the heat.

Internally, the air handler and duct work are not expensive.

When I bid for our current house, the cost tripled for the outside heat sink, so I opted not to do it.

Anyway, I'm very familiar with both.

Edited July 31, 2020 by sherpa

[apuszczalowski]

Out here I have yet to see a geothermal install done. I have read up on them and I guess it really depends on land/area. I believe the vertical install method can be much more expensive but works for smaller lots then the horizontal install. They were offering courses around here about them because they thought they were going to take off but it hasn't happened.

 

As for solar, definitely something you want to have a system designed for, by someone who knows what they are doing. A few years ago, I used to see alot of them being done because of the incentives they were giving out for them. I knew someone who had it done and his son just bought a house and applied for the same. He said the bank had no problem giving him more on his mortgage to cover it when he was approved for the incentives because they knew the incentives paid for it and then some. There were alot of companies popping up doing them, some were going door to door getting home owners to sign leases for their roof where the company would come in, pay you an amount per month and they would use your roof to install panels. These companies seem to have vanished now that the incentives were taken away by the government and I barely see them being installed when you have to pay for it yourself.

 

I think off you have the money, and it's a place you plan to stay at for a long time, it's definitely a good expense. The only downfall is probably maintenance and repair costs years down the road when things need repair or replacing. With solar, if it's installed on your roof, it's going to cost more to replace your roof because there's the extra labour of having to work around or remove the panels to replace the roof. 

[Mr Info]

@sherpa & @apuszczalowski - thx for feedback

 

I obtained 1 quote for solar & waiting on another from established companies. 
We live in an historic area so do not want visible panels on the house. It ends up the far side of the garage (facing away from the house and not visible) is south facing with no shade so that is where the panels would be placed. 
Payback would be ~10 yrs based on calculations for current kWa consumption & reduction from solar. Prob going to do it due to Solar Fed Tax Credit of 26% this year which changes to 22% next year and disappears in 2022.

Getting two quotes for geothermal system next week. This would replace current HVAC systems. Plan to use existing duct work and will ask if current hvac fans can remain. Expect this will have to be a vertical install which will make it expensive so may wait until next year and leverage the tax credit solar system this year.. 
A geothermal system will reduce energy consumption so the solar payback will be extended by a few years. But the solar system we are considering is ~33% of our energy consumption and geothermal may double that by reducing our overall consumption but still below 100%. No reason to give free power to the grid.

[sherpa]

If you're in Ashland, you're a little less than 38 north latitude, so that should be about the slope of the solar installation.  That can be tweaked a bit to obtain a little better efficiency. I'm in Charlottesville, so not much different.

If you do the geothermal, seriously consider the desuperheater for water. I did it in mine and it worked great.

Existing duct work is usable.

The ground source heat pump should cost about the same as a normal air source heat pump, but the vertical closed loop is going to be quite expensive.

I would really press for information on how they intend to ensure contact is made and maintained with the plumbing, as the heat exchange is purely by conduction, and over time heating and cooling can separate the "ground" from the plumbing. I'm sure the contractor will do a great job, but it is something I would want to know. Virginia's clay soil is pretty good at transferring thermal energy, but it can pull away. 

Good luck. I went a different route with this house, but I had no complaints with my geothermal, especially in the summer.

Edited August 1, 2020 by sherpa

[apuszczalowski]

11 hours ago, Mr Info said:

@sherpa & @apuszczalowski - thx for feedback

 

I obtained 1 quote for solar & waiting on another from established companies. 
We live in an historic area so do not want visible panels on the house. It ends up the far side of the garage (facing away from the house and not visible) is south facing with no shade so that is where the panels would be placed. 
Payback would be ~10 yrs based on calculations for current kWa consumption & reduction from solar. Prob going to do it due to Solar Fed Tax Credit of 26% this year which changes to 22% next year and disappears in 2022.

Getting two quotes for geothermal system next week. This would replace current HVAC systems. Plan to use existing duct work and will ask if current hvac fans can remain. Expect this will have to be a vertical install which will make it expensive so may wait until next year and leverage the tax credit solar system this year.. 
A geothermal system will reduce energy consumption so the solar payback will be extended by a few years. But the solar system we are considering is ~33% of our energy consumption and geothermal may double that by reducing our overall consumption but still below 100%. No reason to give free power to the grid.

The reason everyone around here was doing it was because the government program bought back the extra hydro you put into the grid, at an amount more then they charged you for hydro, so people would have them installed, still run everything on hydro from the grid, and sell back as mush as they could from what the solar generated. There were farmers putting up barns for the sole purpose of having more roof space for panels to get on the government program.

 

That government is no longer in power and the current one cut all those programs so now solar and wind turbine companies are disappearing and it's getting rare to see people wanting solar panels

[Augie]

This will be of no help to you, but I found it interesting. They installed a geothermal system at our old club pool in Florida. Not only did it heat the pool when needed, but more importantly  it COOLED it when needed making it pleasant in the summer. That was a great addition.