I've done it. Yet I still keep the grid connected. In case you're interested, I have 5Kw of panels connected to a charge controller. This goes to a 6KW low frequency inverter. I have 20KWH of Lifepo4 batteries. It all works. I do it because I expect the grid to go down sporadically or go off permanently.
Based off your experience, would you say it would be possible to have such a system in a colder climates where it's rainy and cloudy often?
Yes.
You need to find your lowest amount of sun hours per day. And buy enough solar panels based on that. Even if you get 1 hour per day, you can do it. You'll just need enough panels to extract. For example:
If you consume 5KWH per day and you get 1 hour of sun per day, you will need 5KW of panels in order to charge your batteries. If you get 2 hours of sun per day, then you'll only need 2.5KW of panels.
Of course, you'll need to plan some margin in there in case you don't get the same amount of sun every day. But I think you know where I'm going.
You can gang up multiple arrays using multiple chargers.
So I worked from the inverter to the batteries to the panels to determine what I needed.
Consider your house wiring. I used a 6KW inverter because I back feed the inverter to my panel on a branch circuit. My wiring and branch circuit can handle 30 amps @ 220 volts. So a 6KW inverter is as big as I can go without making major changes to my panel.
The batteries depend on how many KWH you need. By the way, I went with 48 volt batteries to keep my wiring costs lower.
Good luck.
Thanks for the info and taking your time to write that. Now I have a lot better idea of what to do.
If I was interested in having some solar installed, is there a reputable company to go through. I have 0 DIY skills and would die or make a huge mess attempting anything like this, but I also don't want to get screwed by some shady solar shlomo.
Also, any gubmint gibs-me-dats to help with the cost?
How's the longevity of your panels?
depends on the clouds
cloudy sky basically reduces everything to nothing
also, there is a sixfold DECREASE of solar energy between winter and summer .... (in most part of the world, beside equator)
so, if you have batteries (yes, 20kwh is a proper sizing for a house) also get a generator,
being grid connected is less "complicated" but a bit more expensive
also, there is a sixfold DECREASE of solar energy between winter and summer .... (in most part of the world, beside equator)
This would be a huge factor as the area where the property is gets proper frigid during winter, so thanks for the heads up.
Are there guides or other resources you recommend to start learning how to set this up?
Thanks in advance!
There are many resources. It took me a while to comb through the info I found. I found unboundsolar has pretty good resources. You need a solar calculator for where you live to determine your solar days. This will help you size your panels. Then you need a household watt calculator to estimate your power requirements. Also, your electric bill is helpful for this. Keep in mind during a crisis, you may not need as much power as you would normally use. For example, I won't run my air conditioning or my electric clothes dryer.
Electric motors, such as septic tank and well pumps have very high current requirements to start them. This will affect the type of inverter you may need. I went with a low frequency inverter because of my high current requirements for all my pumps. A high frequency inverter is much cheaper and more efficient than what I bought because I needed the instantaneous starting current a low frequency inverter offers.
Lifepo4 batteries are the best bet, they can be cycled much harder and more frequently than flooded batteries. Yes, they cost more, but I determined the cost was well worth it. Having said that, you can buy cheap (China made) banks of batteries since the individual cells are all the same. China makes them all. Sadly. I did buy batteries assembled here in the USA so I paid more probably than I needed to.
The panels, well, I bought the cheapest ones I could find. Again, most of these are made in China. The MPPT charger, I bought MidniteSolar. It seemed reasonable for the money.
Good luck.
Midnite is a great company, good stuff. The PNW has a bunch of good solar companies, all sort of interconnected over time. I ran a midnite classic for a decade.
Start browsing diysolarforum.com, it’s the greatest resource I have ever found.everything Is there.
I want to for if I get rid of my current house. Need to get a more open lot though.
I'm in a prescribed northern zone. How does latitude affect solar power and how are these calculations made?
Go on your favorite search engine and look for "off grid solar calculator". It will ask you for your zip code and may ask for your load size. You will then get your minimum number of sun hours for your area.
The calculations are based on your position on the earth. There's probably a table with this data somewhere. I frankly don't know. This is how I sized my system.
I know I use less than 20KWH per day of energy, based on my electric bill. I get more than 4 hours minimum of sunlight per day based on the calculator. This means I need 5KW of solar panels. However, you may need more if you don't have a clear area.
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