How to Colonize an Asteroid
How to Colonize an Asteroid
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This system is "the work horse", providing power for lights, a laptop PC, soldering iron, television, video games, a popcorn popper, and the model rocket launch controller , (among other things). OK - it's not an awesome system, I can't have all of those things operating at the same time, but it provides a usable amount of power, if managed carefully.
Power is generated by three solar arrays on the south
facing roof of the shed. Each panel is rated at about 14 volts under full
sun, at around 900ma. The panels are wired in parallel, for a total current
output under full sun of around one and a half amps. The panels are more
sensitive to ultraviolet light than they are to visible, so the cells still
put out about 60% of their rated power on a cloudy day. (Which is good here
in upstate New York, where we average 2.3 hours of full sun a day!).
The power produced by
the cells is routed through the wall of the shed to a monitoring box mounted
on the wall, which contains meters to measure the current and voltage coming
from the cells.
From there it is routed to a
terminal block where it is connected to the "Bus" in the shed - which is
the main 12vdc distribution system. Connected to the ground side of the power
bus is an 8 gauge wire which goes outside to a 4/ inch copper rod sunk 6
feet into the ground.
Throughout the shed there are
junction boxes, terminals, and cigarette lighter outlets where you can tap
the 12 volt power. Mounted in the ceiling are two automotive dome lights
(10 watts each), and a ceramic socket with a 50 watt bulb from an RV supply
store. I normally use the 50 watt light for short periods, as the 2 dome
lights do a fair job by themselves (and they consume a lot less power!).
Also connected to the bus are two 100amp-hour "gell
cell" batteries. These are basically standard lead acid batteries with a
gelled electrolyte. You will note that this system, like the radio system,
has no charge regulator. This is possible because of the extreme difference
in the current produced by the solar cells and the capacity of the batteries.
The sun would have to shine every day for at least sixty days (and I would
have to go without using the power) before the batteries would even come
close to reaching capacity. It will never happen (here). If you live in a
more sunny location than I, you need to use a charge regulator so that you
do not damage your batteries.
