Show your solar/alternative home energy source

[Bmachine]

Spurred on by some postings in another thread I figured now is a good time to start one dedicated to this subject. There have been several mentions of interesting options here and there on the forum in the past. I remember being especially interested in Robert Gransin’s geothermal installation.

We have had solar panels powering our houses for the last eight years or so. It is an immensely liberating feeling to know that, not only are we not dependent on an outside source for electrical power, but all the power we use is clean, renewable and does not use any fossil fuel.

We just had a 7.2 kW Tesla system installed on our newest house. This time we included two Powerwall batteries which can store up to 27 kW. This means that during the day the solar panels feed the house and recharge the batteries which then power the house at night. These days, with the lockdown in place, there is something really comforting in knowing that even if the power grid gets to be disrupted we are completely independent of it.



Cost wise, the system retailed for $35k including installation in December 2019. It came with a 30% tax credit which we got back recently, making for a net cost of about $24k.

 

[Bmachine]

During the day the system powers the house and recharges the batteries.



When the batteries are full, it sends any excess power back to the grid.

 

[craterface]

Love it! How much does a system like that cost? What are the current tax incentives? Is there still a 30 percent tax credit from the Federal Gov?

 

[Bmachine]

Haha, I was editing the original post to include that info right as you were typing the question.

To answer the second part, I believe that in 2020 the tax credit is now 22%.

 

[steve in reno]

During the day the system powers the house and recharges the batteries.

View attachment 88491

When the batteries are full, it sends any excess power back to the grid.

View attachment 88492

Here is my hot water system. The util rm will confuse, but there is 4 different systems in that mess.
Solar , heating , recirc , tankless loop.
I retired as a plumber, building contractor.
The gray boxes on wall each control one, or more. All made by elect friend.
Outdoors pic of panels have morning frost.
Very simple drainback system

 

[steve in reno]

 

[adawil2002]

Pulled over from the other thread.
Our photovoltaic solar panels were installed on the garage in March of 2016, it's a 9.1kWp system and helps offset the electric bill. Will pay for itself in 8 more years. We have an automatic inverter switch so if we lose grid power & the generator takes over the solar panel power turns off at the inverter. Would love to add a Tesla battery array in the future.

 

[Bmachine]

9.2kw is a pretty beefy system. Do you use electric heating?

 

[adawil2002]

9.2kw is a pretty beefy system. Do you use electric heating?

No electric heat. The system was designed based on our power consumption to make it close to net zero or +1 so we produce a little more than we need.

 

[Gransin]

I remember being especially interested in Robert Gransin’s geothermal installation.

Hi Bo, yes we have a geothermal system in our house and we love it.

It's a Finnish brand called Lämpöässä, our pump model is VMI 11: (english link)

Vmi-model series - Lämpöässä

www.lampoassa.fi

The pump gets its heat from a (220meter deep in my case) borehole and it works so well, just set and forget!
I wish I had the $$$$ to drop on a solar system just like yours and add it on top of this system, in the future...

 

[Bmachine]

I wish I had the $$$$ to drop on a solar system just like yours and add it on top of this system, in the future...

I am guessing that, as usual, costs vary widely depending on location. Over here, solar is very popular, therefore *relatively* affordable. $24k in our case and it powers everything in the house except for the stove which is still using propane gas.
On the other hand, I looked at a geothermal system like yours and I got quotes well above $100k and time table of over a year because of the strict environmental regulations.
By comparison, how much did your geothermal cost?

PS: 220m deep? That is insane. Can you see Australia from down there?

 

[Gransin]

I am guessing that, as usual, costs vary widely depending on location. Over here, solar is very popular, therefore *relatively* affordable. $24k in our case and it powers everything in the house except for the stove which is still using propane gas.
On the other hand, I looked at a geothermal system like yours and I got quotes well above $100k and time table of over a year because of the strict environmental regulations.
By comparison, how much did your geothermal cost?

$100k
That's crazy, yeah we're not anywhere near that amount over here, my parents recently had a Bosch pump + borehole installed and the bill was 15k€ with installation and everything included so that's why this is extremely popular around here, the running costs are very low once you have it installed, and all the maintenance you have to do is to inspect a filter once a year and maybe top up the fluid in the expansion tank for the borehole once every third year (if even needed).

I'd say a solar system comparable to yours is around the same amount as you paid, maybe a little higher. Since the geothermal systems are half the price, that's what most people go with when they're looking for a complete heating system. Many still add a couple of solar panels but that's just because it's fun I guess.
I'd want a solar panel setup (maybe not quite as big as yours) only for the fun and because it's interesting. Beeing more independent is also a big plus.

 

[Bmachine]

$100k
That's crazy,

Part of the problem is that we don't have enough room to do a horizontal system and that it is rocky terrain. Therefore drilling straight down is difficult and expensive.

 

[Markos]

I didn’t even realize they had vertical heat pump systems. Very cool stuff! I need to revisit the solar options. My quote was $40K, but that was about five years ago from an American made solar cell (which now went out of business I believe).

 

[Gransin]

Part of the problem is that we don't have enough room to do a horizontal system and that it is rocky terrain. Therefore drilling straight down is difficult and expensive.

Over here we have an average of 6 meters until you hit hard rock, that's what they estimate if you get a quote.
The funny thing is, it's much more expensive if you have a deep layer of dirt until you hit rock, because that upper part of the borehole needs to have a big thick expensive steel sleeve inserted to prevent the water pipes from getting crushed. So at least here, drilling straight down into rock, is cheaper than drilling a borehole through a layer of dirt.

It usually takes one workday for a small crew to come out and drill, put down the sleeve, dig for the pipes and finish everything off, then another crew comes out and installs the pump.

Drilling action + installed pump at my parents:

 

[Bmachine]

Over here we have an average of 6 meters until you hit hard rock, that's what they estimate if you get a quote.
The funny thing is, it's much more expensive if you have a deep layer of dirt until you hit rock, because that upper part of the borehole needs to have a big thick expensive steel sleeve inserted to prevent the water pipes from getting crushed. So at least here, drilling straight down into rock, is cheaper than drilling a borehole through a layer of dirt.

It usually takes one workday for a small crew to come out and dig, drill, put down the sleeve, the pipes and finish everything off, then another crew comes out and installs the pump.

Very interesting. Economies of scale at work. In our area, geothermal is sadly much less used than on the east coast or, obviously, Finland in this case. Hence the cost difference.

 

[steve in reno]

We have geothermal here but not much. We have very high mineral content and it crusts the pipes interior so much the maintenance is too high.
We do have a geothermal plant that puts out a good amount of electricity. No idea of its depth needed for use.

 

[steve in reno]

Just checked my temps and the 400 gal tank is at 125 degrees, which will give enough heat for the entire night. It has been partly cloudy for last few days which cuts into the heat. The storage tank sensor turns off all of system when temp goes to 150 degrees. That is 2.5 days of heat. I can run hotter, but it lessens life of tank which is a high performance rubber(?) tank that was custom made for this purpose. ($600). I replaced 4 years ago and is the first money I have spent in 18 years of use on this house, other than sensors. I have never had to replace a pump motor, 2 homes and 30 years pf service.
I have a radiator style heater in the lvrm that heats entire home. It is quiet and cheap to operate.

 

[CSteve]

Just checked my temps and the 400 gal tank is at 125 degrees, which will give enough heat for the entire night. It has been partly cloudy for last few days which cuts into the heat. The storage tank sensor turns off all of system when temp goes to 150 degrees. That is 2.5 days of heat. I can run hotter, but it lessens life of tank which is a high performance rubber(?) tank that was custom made for this purpose. ($600). I replaced 4 years ago and is the first money I have spent in 18 years of use on this house, other than sensors. I have never had to replace a pump motor, 2 homes and 30 years pf service.
I have a radiator style heater in the lvrm that heats entire home. It is quiet and cheap to operate.

We were early on to passive solar. In 1978 we built a 1650 sq foot house. Located in Bucks County PA north of Philadelphia. Three levels, slab on grade, no attic. Open from the first level to the roof, double glass walls on the south side, two small windows on the north side, slightly larger ones on the east and west walls. 2x6 or 2x12 studs/rafters. An early heat pump for an all electric house. We are in the woods so shade in the summer, full sun in the winter. For the first 35 years we had a Danish wood stove. Burned two cords a winter($450 average cost for two over those years).

We were never cold or hot. Just right as baby bear said.

We stopped using the wood stove a couple of years ago. I am 78 and the stacking and hauling and maintaining the stove got to be a little much.

Our first heat pump lasted 27 years. The second one is still humming, much more efficient.

So here's the result. I averaged in the cost of two cords of wood per winter. Over the course of 42 years our monthly electric bill has averaged $137.00 per month.

That's $137.00 a month to run the entire house. Everything.

 

[Stan]

Three of my neighbors have photovoltaic cells on the roof. One of which was installed yesterday.
I think, when I ran the numbers, I would not live long enough for the ROI.