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shovel · 03-12-2009, 01:34 PM

OK dumb question time (but I couldn't find useful info online..)

I would love to buy a kW of solar panel, to connect to a little 5000btu window a/c unit, to keep my bedroom cool. I live in Phoenix and my bedroom is upstairs so it stays hot all the time, and I figure if I can keep it cool for "free" during the day that will take a heck of a load off the central A/C, day and night (in the evening, it won't have to cool off all the items with mass such as furniture, clothes, etc)

However it's just simply not in the cards right now to front cost for something that will take 5+ years to pay off. I know that's not TOO long but I just can't afford it today.

What I can afford today is a ~200w panel and I already own a computer UPS. - I don't use the UPS anymore because I only have a laptop nowadays.

The UPS contains a pair of rather large sealed 12v batteries, together they are as large as the battery in my S10.

I don't know a ton about electronics, but I was thinking, can I feed a regulated 12v from the solar panels to the batteries in the UPS as a "grid tie" to partially offset the load of whatever is connected to it? Or are the batteries disconnected during normal operation?

Thanks!

03-12-2009, 01:34 PM	#1 (permalink)
shovel Master EcoModder Join Date: Feb 2009 Location: Phoenix Posts: 593 Thanks: 106 Thanked 114 Times in 72 Posts	DIY solar - to - grid tie OK dumb question time (but I couldn't find useful info online..) I would love to buy a kW of solar panel, to connect to a little 5000btu window a/c unit, to keep my bedroom cool. I live in Phoenix and my bedroom is upstairs so it stays hot all the time, and I figure if I can keep it cool for "free" during the day that will take a heck of a load off the central A/C, day and night (in the evening, it won't have to cool off all the items with mass such as furniture, clothes, etc) However it's just simply not in the cards right now to front cost for something that will take 5+ years to pay off. I know that's not TOO long but I just can't afford it today. What I can afford today is a ~200w panel and I already own a computer UPS. - I don't use the UPS anymore because I only have a laptop nowadays. The UPS contains a pair of rather large sealed 12v batteries, together they are as large as the battery in my S10. I don't know a ton about electronics, but I was thinking, can I feed a regulated 12v from the solar panels to the batteries in the UPS as a "grid tie" to partially offset the load of whatever is connected to it? Or are the batteries disconnected during normal operation? Thanks!