solar backup?

seeing the thread on ecoloblue reminded me of this product that I had seen a few weeks ago and was considering buying.

mysolarbackup.com...

anyone have any experience with this item?

thanks

[edit on 9/15/2009 by LiveFreeOrDie..]

I personally have never trusted websites with that sort of design offering goods/services.

By "that sort of design" I mean very home-made looking, packed with loads of text trying SO hard to sell whatever it may be...

Just my opinion.

reply to post by LiveFreeOrDie..


Check out my thread .. there is all kinds of Alternative Energy resources in there.

You can build SP.R.E.E. for allot less.

What A Great Resource For ATS Survival

Alternative Energy DIY

S.P.R.E.E. (Solar Photovoltaic Renewable Electron Encapsulator) A Compact, Durable, and Portable Solar Energy Generator

SPREE

[edit on 15-9-2009 by The Utopian Penguin]

Stay away, looks cheesy to me . . .

It appears to be a run-of-the-mill 2000va (~1800 watts) UPS system (battery backup you would use for a large workstation or server) hooked up to a 90w solar panel for charging.

The solar panel is maybe worth $500

Notice it doesn't say anything on there about how long this "solar generator" lasts on a full charge. A typical 2000va UPS system will run about 7-10 minutes at full load (1800 watts). 1800 watts will *maybe* run your fridge and a few lamps.

Based on the unit's size I wouldn't bet much more than 10 minutes or so at full load, maybe 25 minutes at half load. It's not much bigger than a breadbox and with existing battery technology you just can't store very much power in that size container.

Your "generator" (i.e. battery pack) can produce 1800 watts but your charging capacity is only a single 90 watt solar panel. You are using up power 20 times faster than you can produce it. Once the battery runs out you have a 90w solar panel for electricity. Maybe enough for a small radio, provided it's sunny outside.

Now here's where it starts to really suck . . . (sorry my nerdy side is about to show)

So let's say it uses two 12v, 18ah (amp-hour) batteries (pretty typical for your average UPS system).

To charge the batteries:
18ah 12v battery needs 12v @ 18amps for one hour to fully charge
x2 -- two batteries means 2 hours @ 18 amps to charge
Total amp-hours needed to charge is 36ah @ 12v

Solar panel output:
90 watts, assumed to be 12 volts = 7.5 amps

So, with 36 amp-hours needed to charge your batteries, your solar panel @ 7.5 amps would take 4.8 hours to recharge the "generator" so you could get another 10 minutes of 1800w power. Keep in mind that's 4.8 DIRECT SUNLIGHT hours, and to be safe I'd add 20% to account for innefficiencies in the system, so probably more like 5.5 hours or so.

Sorry for the long technical post -- just want folks to realize solar panels, while very cool and all, really don't produce very much power per their cost. So many websites out there selling them like you can plop a couple panels on your roof and save 20% on your electricity bill -- it's just not true. You need a HUGE investment to produce enough power to run 20% of your house. Typical solar installations don't "pay themselves off" with electricity savings for 10 years or more.

thanks for the input. I agree it seems cheesy and of questionable value. thats why I didn't bite, but I figured I'd give someone thats bought it a chance to change my mind