10kW Ground Mounted Solar Panel System

[part-time-Farmer-NC]

I didn't see any mention of your current amps needed at a time. I know you stated you use about 600 kw a month. When sizing solar, especially without batteries wouldn't you need to factor the expected loads during peak/off peak loads? Using your 600KW @ 240 volts (2500 amps ish) number that averages to 83 (ish) amps per day not per instance.

Is 10,000 kw enough to run all/most electrical in your house? At 240v that equates to about 41 amps of current available at full power. Or 83 amps for 120 volt appliances. Heat or AC (depending on its requirements) and you have used much if not all of that, not too mention hot water heaters, electric stoves, hair dryers etc. Lights are very minimal in needs if using LED.

I have a 12000 W gen that only produces 50 amps. I can "get by" with that for an outage. Here that can be a few hours to a week (rare but it has happened).

Solar without batteries to subsidize the loads weakens the whole off grid/emergency strategy to daytime use only. The cost per KW for solar is too rich for my blood and not using the batteries restricts it to peak daytime use and costs go up substantially.

 

[ponytug]

The outgoing administration just recently added tariffs back on biracial panels. They were exempted for a while. Might explain the good pricing.

I saw a video from Germany, where they experimented, and found vertical mounting actually gave the best daily output with biracial panels.
The drop in efficiency at peak hours was more than compensated by early morning and evenings.
It also eliminated snow loads.

I would bear in mind that Germany is much farther north than much of the US, so the results may not be directly applicable, e.g. Berlin is at 52N, vs say, Portland ME, at 43N.

We are at closer to 37N here, and vertical bifacial does not win out year round, as in not even close.

That said, some of us need the power more in the winter, and it can be worth setting the panel angle steeper to increase winter production, at the expense of a small drop in summer production. I think that PVwatts is your friend on running scenarios for any specific location.

All the best,

Peter

 

[JasperFrank]

I have a friend that installs and maintains large PV solar systems. The really big ones from four to 20 acres. He works all over the USA. Once you are installing below 40 degrees Lat, adjusting for seasonal sun angle doesn't matter, according to him.

 

[orezok]

I have a friend that installs and maintains large PV solar systems. The really big ones from four to 20 acres. He works all over the USA. Once you are installing below 40 degrees Lat, adjusting for seasonal sun angle doesn't matter, according to him.

I’m at about 34 Latitude and all the solar farms (very large farms in he Mojave) have single axis control. I think your friend is mistaken. They wouldn’t spend the $$$ if it wasn’t productive

 

[MAX-24-Dean]

Here are the specs on the panels:

China 750 Watt Solar Panel Manufacturers Suppliers Factory - 750 Watt Solar Panel in Stock

We're well-known as one of the leading 750 watt solar panel manufacturers and suppliers in China. Please feel free to buy or wholesale high quality 750 watt solar panel in stock here from our factory. For price consultation, contact us.

www.jingsun-power.com

I looked at the home page only and the banner says 60 cents to 95 cents per watt.

At the link below the panels are listed by price per watt and they have lower pricing. Stock already in USA.

All Products - Solar Panels - Signature Solar

Signature Solar's premium panels deliver top-tier efficiency and durability—powering your energy needs with unmatched performance!

signaturesolar.com

 

[ericm979]

I didn't see any mention of your current amps needed at a time. I know you stated you use about 600 kw a month. When sizing solar, especially without batteries wouldn't you need to factor the expected loads during peak/off peak loads?

Only if it's off grid. Then you need batteries. Depending on the array and battery size you may want to schedule power hungry tasks for when the panels are making lots of power, so they don't cut back because the batteries are full.

On grid without batteries, the grid is your battery. If your utility has net metering then you get paid for what you put in at a rate close to your costs when you pull from the grid. So you can run the house at night on "your" power, or overproduce for your needs in the summer and get that energy back in the winter,

Some states or utilities are moving to a model where you get paid much less for the power you put into the grid than you pay to take power from the grid. California for one. They also have time based metering where power is more expensive at high demand and low solar times (late afternoon/early evening). Under a rate scheme like that you use batteries to time shift your power to ensure that you use minimal power from the grid during the high rate hours.

Moving to more efficient HVAC like mini splits and appliances like heat pump water heaters will make the solar power go farther.

Since most people finance solar installs, if you're on a scheme like CA's NEM 3.0, you just add batteries to the project. As long as it pays out in a reasonable time it doesn't matter that much. If it doesn't pay for itself then most people won't do it.

 

[Pettrix]

I looked at the home page only and the banner says 60 cents to 95 cents per watt.

At the link below the panels are listed by price per watt and they have lower pricing. Stock already in USA.

All Products - Solar Panels - Signature Solar

Signature Solar's premium panels deliver top-tier efficiency and durability—powering your energy needs with unmatched performance!

signaturesolar.com

My costs are around 0.10 cents per watt for the panels

 

[MAX-24-Dean]

Thats incredible, but the rumor is buy before January 21st. as pricing may go up.

 

[grsthegreat]

All I can say is it cost more than I thought it would going in. I wanted this for power outage back up and to knock down our monthly bill overall, Would I recommend it as a money saver out of the gate? Heck No, but our power rate is only $.08- $ .10 per KWH. Some of the states where power can cost a lot during certain hours a hybrid with solar and batteries might make a LOT more sense.

i have one customer that had a solar system installed along with upgrading their backup generator to 24kw. he had a power outage, generator came on......house dark. batteries didnt switch over and even though generator was running, nothing was being powered. i was called to look at it...its over my head. the installers pulled the transfer switch off the wall. i had no idea where the gen power was even going. likely to inverter, but from there i have no idea. i didnt want to get in the middle of a $150,000 nightmare.

i also pay less than $0.10/kwh in north idaho. no solar for me

 

[ultrarunner]

With the kW price as high as 60 cents and getting a check each year for excess production the 6 kW system of 2008 panels and inverter keeps me smiling…

It produces all the electricity I use and then some in a 3200 square feet home.

Ground Mount works because it’s so easy to rinse the panels once or twice over a dusty summer with no rain for months.

Also no tools needed to change the tilt 2x per year.

Your mileage will vary.

 

[sd455dan]

I looked at the home page only and the banner says 60 cents to 95 cents per watt.

At the link below the panels are listed by price per watt and they have lower pricing. Stock already in USA.

All Products - Solar Panels - Signature Solar

Signature Solar's premium panels deliver top-tier efficiency and durability—powering your energy needs with unmatched performance!

signaturesolar.com

Yeah I paid about 40 cents a watt Delivered from Signature Solar and the Boviets are a Tier 1 manufacturer.

When I went to that link the same .60-.90 price per watt popped up on the left side of the screen.

Hope that includes from China shipping, tariffs , customs, taxes, and to home lift gate delivery.

 

[sd455dan]

i have one customer that had a solar system installed along with upgrading their backup generator to 24kw. he had a power outage, generator came on......house dark. batteries didnt switch over and even though generator was running, nothing was being powered. i was called to look at it...its over my head. the installers pulled the transfer switch off the wall. i had no idea where the gen power was even going. likely to inverter, but from there i have no idea. i didnt want to get in the middle of a $150,000 nightmare.

i also pay less than $0.10/kwh in north idaho. no solar for me

Wonder if that installer outfit is still in business, Pretty dumb to pull a perfectly good manual transfer switch, especially if something does go wrong with the inverter/batteries etc. Some of these fly by night installers I wouldn't trust to change a lightbulb.

 

[DarkBlack]

With the kW price as high as 60 cents and getting a check each year for excess production

You’re lucky if you can still get a profit check. They eliminated that benefit some years ago, here. Now the best you can do is offset your grid usage with production credit. No profits from excess allowed.

Even so, I’m still interested in solar systems, from a technical standpoint, but without a ridiculous 60 cents/kwh rate like you have, ROI is around 8 years here, optimistically…
S&P averages a doubling in 7 years, and has no maintenance, or land requirements. The later is the obvious better investment, for my scenario

 

[ultrarunner]

You’re lucky if you can still get a profit check. They eliminated that benefit some years ago, here. Now the best you can do is offset your grid usage with production credit. No profits from excess allowed.

Even so, I’m still interested in solar systems, from a technical standpoint, but without a ridiculous 60 cents/kwh rate like you have, ROI is around 8 years here, optimistically…
S&P averages a doubling in 7 years, and has no maintenance, or land requirements. The later is the obvious better investment, for my scenario

Im under the old tier which will eventually sunset.

My annual True Up averages about $300 to $350 positive to me.

That said the minimum monthly meter fee runs about $165 annually...

So I'm in the black $150 to $180 after deducting the annual meter fee every year since commissioned in 2017...

I watch my usage and like most have LED lamps, well insulated plus triple pane windows...

 

[Roric]

Our 7.5kw system was commissioned in Dec. 2019 and has produced 45 Mega WH, about 9000kwh per year or 750kwh per month. Our rate has gone up several times over the years, along with the list of charges added to the monthly bill.
At the start we were a bit ahead on the production/use ratio and had credits on most monthly bills.
We went to more efficient products as we replaced old ones as needed.
(Split unit for A/C, led lamps for incandescent etc.)
The electrical loads for our 2600 sq foot house include:
wall oven, free standing range, counter cook-top, 2 electric clothes dryers, rarely used garage heaters, and a counter top hot water standby heater for coffee and tea.
When we later added a plug-in-electric-hybrid and also a full EV to our garage. These put a small bill back on our table most months.
But since we got a "REC/rewards" credit of 7 cents per kwh of production check each year (the 9000X.07 equals about $600.00)
a year. Not unlike your yearly true-up payment.
This means we finish in the black for the year too.
Since I installed this array and did the labor the payback was last year.
Not bad for the snow covered tundra of Minnesota.

Regards,

R