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How to select best UPS and Solar to be off-grid 24 hour for 2kw

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Re: How to select best UPS and Solar to be off-grid 24 hour for 2kw

#12
post #4

That's 48kWh. You're going to be looking at a setup that's a few thousand dollars.

Few tens of thousands of dollars.

You're looking at 4 hours insolation in winter in subsaharan regions. Also assume cloud cover drops panel output to 50% for consecutive days. You're gonna need 25kW of panels and 30kWh+ of battery storage.

Re: How to select best UPS and Solar to be off-grid 24 hour for 2kw

#13

2kw draw for 24h is actually quite substantial. Don't forget regardless of how sunny it is in Africa, You will still need to have enough stored power to make it through the night. I'm not saying it is impossible but suspect it will cost more in fuel to transport the batteries and panels than it would to just run a small inverter genset instead. If your device doesn't need to be constantly powered then I would suggest…

A generator will consume roughly a liter of diesel per hour at this load. For a stationary installation, a diesel generator would be a terrible idea.

Re: How to select best UPS and Solar to be off-grid 24 hour for 2kw

#16
I've had really good results with SMA Sunny Island.

It acts as "the grid". It's connected to batteries, and gives you a 230/120V network. Then, you had a normal solar inverter. It'll recharge the batteries when the inverter gives power, and power your equipment when it does not.

Big plus is that if someday the grid arrives at your home, you can simply take it away and you won't have to touch your solar panels.

Re: How to select best UPS and Solar to be off-grid 24 hour for 2kw

#18
I would recommend watching Will Prowse YT channel. For batteries, I'd say BattleBorn. They're expensive but have a 10 year warranty and are just damn good batteries. Probably among the best you can get. They should easily last 10+ years. Will goes over everything. He tests MANY batteries, panels, inverters, etc., and goes over how to size your system based on your needs and location.

https://www.youtube.com/channel/UCoj6RxIAQq8kmJme-5dnN0Q

Re: How to select best UPS and Solar to be off-grid 24 hour for 2kw

#20
ClumsyPilot mentioned this, but it's worth repeating - if your load is expecting AC power but is converting it to DC (eg computer power supplies) you can probably save quite a bit by looking at fully-DC options so you skip the DC-AC-DC conversion stages.
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