Power outage solar backup
Mark and I are in the
research stages of putting together a very small solar backup for use
outages, and I'm
hoping that some of the more technical folks among you can give us the
benefit of your wisdom. During three power outages over the last
few months, we've figured out that running the generator for an hour a day keeps the
farm ticking along, but that we miss two major creature comforts ---
lights on winter evenings and more steady access to the internet.
Luckily, these gadgets
don't draw much juice --- about 25 watts apiece for our laptops,
another 23 watts for the router, and 13 watts for a CFL. We
figure that if we increase efficiency by buying a car charger for the
laptops (deleting the inefficiencies from converting DC to AC to DC)
and buy a couple of DC LED lights, we could coast along on very little
electricity, allowing us to work and play online for perhaps 3 hours
per day on a solar system costing less than $300.
simple solar system that doesn't seem to require much technical
know-how consists of a 600 watt Duracell Power Pack (basically, a 12
volt, 28 amp-hour, AGM battery; a controller; and a 600 watt inverter
combined into one unit, costing roughly $125) along with a 25 to 30
watt solar panel (roughly $150.) Many solar panels come with the
right connectors, so the system would be basically plug and play.
The flaw I see in the
combo above is that the solar panel might not fully charge the battery
in a single day of sun --- some websites say the system will charge up
in 5 to 7 hours, but other sites think the system will take 16 to 18
hours to charge. We can't just add a larger solar panel for
quicker charging since the manufacturer notes that you can't hook a
panel larger than 30 watts directly to the power pack without adding an
external charge controller.
So here are my questions:
- Is it okay to shop around and find the cheapest 30 watt solar
panel, or are cheaper solar panels going to burn out quickly? Are
there solar panel categories I should be aware of in the low end,
- We're willing to pay a bit extra for plug and play (and
portability), but don't want to be seriously ripped off. Would it
be smarter to do more research and buy the battery, inverter, and
charge controller separately?
- If we bought an external charge controller and a 50 watt solar
panel, would the larger panel charge our power pack faster? My
very vague understanding makes me think it wouldn't, that the charge
controller would just filter out the extra power from the larger solar
panel since it's more than the battery can handle.
- One website notes that this system would give us around 160
watt-hours per day. I'm not actually sure where people came up
with that figure --- does it make sense? Does that mean that I
could run a single 25 watt laptop for 6 hours?
questions all come down to one major one --- is this a bad idea?
We like the modular nature of the system, especially since Mark thinks
we could use the power pack with pedal power, a bit like this article describes. But we
don't want to spend a few hundred bucks on a dud.
DIY types will enjoy our homemade chicken
waterer kit that
allows you to build your own automatic chicken waterer in less than an
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