?? How many PV Panels needed to heat the house ?

Post by **davidmcbeth3** » Fri. Aug. 18, 2023 5:11 pm

Assuming burning rate of 1 ton a month. Calc out to about 7500 Kwh OF ELECTRICTIY

How many PV panels (or kwh PV system) needed to heat house with only electric heat ?

Remember , its in the winter time...so PV systems in NE will not produce rated amt but lower output.

If member has PV system and knows output (summer or winter kwh / mo.) please note time period of kwh output and size of system.

Post by **LTStorm07** » Sat. Aug. 19, 2023 6:14 pm

When you get a system sized, the solar companies can tell you the average it'll produce per year. You have to be careful because a lot of the fly by night companies over promise and under deliver. They tend to size them for 120% average year usage. Certain power companies only let you install a system that is 120% based on last 12months of usage. So if you were going to switch, you'd have to be pulling the electric before it is sized. I certainly wouldn't consider switching unless you have heatpumps. With using 7500kwh a month, that is a monster usage per month. Even with 0.15 cents per kw, that's over $1000 a month. You would need to figure how much coal per winter you use and then figure out electric on that. If you truly needed something to fit your size, I'd bet it would be 30-45,0000kwh and probably $100k+ installed. To give you an example, a system producing an average of 23,500-25,000 kwh (19.2kwh system where I live) a year will run you around 90k now, maybe more installed. That was the price this past spring. I have a 19.2kw system (48 panels) I had installed spring of '22 when it was a lot cheaper. Maybe you could do it yourself a lot cheaper, but there is a lot of paperwork involved for permits, applications to power company, approvals, etc. I didnt want to deal with all that and had a local well known company do mine.

Post by **LTStorm07** » Sat. Aug. 19, 2023 6:16 pm

Forgot to add, mine is a ground mount with perfect direction and angle. It makes quite a difference. I have many family and friends who have solar as well locally, hence first hand knowledge this stuff.

Post by **davidmcbeth3** » Sat. Aug. 19, 2023 7:42 pm

LTStorm07 wrote: ↑Sat. Aug. 19, 2023 6:16 pm Forgot to add, mine is a ground mount with perfect direction and angle. It makes quite a difference. I have many family and friends who have solar as well locally, hence first hand knowledge this stuff.

Whats the output of your system in Nov-Feb ?

Post by **LTStorm07** » Sat. Aug. 19, 2023 8:03 pm

Oct: 1.9mwh
Nov: 1.6mwh
Dec: 1.1 mwh
Jan: 912 kwh
Feb: 1.7 mwh

I have no trees or anything shading it either.

Post by **davidmcbeth3** » Sat. Aug. 19, 2023 8:53 pm

Neat. Then for 100% electric heat (= to one ton of coal per mo) one would need about a 140 kwh system to be totally off the grid and heat with electrical heat (baseboard I guess) for the winter months.

" You might expect to pay $172,500.00 for such a system." https://quotes.solarproof.com.au/system-sizes/150 ... s-figures/

Interesting

Post by **LTStorm07** » Sat. Aug. 19, 2023 11:49 pm

Keep in mind that's without batteries. Batteries cost as much as the system itself lol. That's why I mentioned if you use heat pumps, the cost would be cut down drastically. I have an efm 520, a new lennox top of line efficiency heat pump, and a newer modulating condensing propane boiler. It's all configured in a hydroair setup so I can actually heat with any of the 3. I tend to use the heat pump all of the time and then when it needs AUX, the efm 520 feeds the hot water coil at the end of the air handler. The efm also heats the dwh in indirect hwh.

Post by **davidmcbeth3** » Mon. Aug. 21, 2023 5:38 am

https://www.google.com/shopping/product/1?client= ... LMQ9pwGCAU

Lennox heat pump , at low low cost of $13,000. That's about 7+ years of coal fuel.

Post by **davidmcbeth3** » Mon. Aug. 21, 2023 12:51 pm

Thinking more .. for all electric heat ... 7000 kwh/mo. would equate to 7000 kwh/mo*5 mos (where heat is needed, est) = 35000 kwh .. one would need a 35000 kw system.

Recalling first post of this thread: Going Solar

It looks like for each or per each 10000kw system = $33500.

Making a 35000 kw system = $117,250

Even with coal at $500 / ton, that's 2345 tons of fuel.

So what do you want ? To spend $117,250 and get "free heat" after that large expense

Or take that $117,500 and plunk it into a 5% cd and earn $5850 a year ( = to 12 tons of coal) ?

To pay for 5 tons of coal ($2500 est) with a 5% CD or something it would need a $50,000 per yr investment to pay for the coal fuel for the season.

This is all for like electric baseboard heating or similar...most electric heaters have the same efficiencies.

Now for heat pumps, if folks have values of cost and operating costs, happy to see them. We all want to save da monies.

Post by **warminmn** » Mon. Aug. 21, 2023 2:24 pm

"Making a 35000 kw system = $117,250
Even with coal at $500 / ton, that's 2345 tons of fuel."

Snip from DM above... $117,250 would be 234.5 tons of coal, not 2345. Im not sure you have the KW stuff right either but will let those with these systems comment on that.

Post by **davidmcbeth3** » Mon. Aug. 21, 2023 3:27 pm

warminmn wrote: ↑Mon. Aug. 21, 2023 2:24 pm "Making a 35000 kw system = $117,250
Even with coal at $500 / ton, that's 2345 tons of fuel."

Snip from DM above... $117,250 would be 234.5 tons of coal, not 2345. Im not sure you have the KW stuff right either but will let those with these systems comment on that.

Correction agreed with ... only 58.5 years of coal fuel for 4 tons/year.

A typo ... my cat will be admonished