GardenBanter.co.uk - Solar powered air pump?

"Sam Hopkins" wrote:
Anyone know of a solar powered air pump?

No, but there's nothing to stop you from making one. The materials are
readily available (look on the net for solar panels).

However, having been involved in a project to "solarize" buoys (and
other things) for the Coast Guard, I can tell you that the technology
has been well understood for decades. A solar panel, a battery, a
voltage regulator, and a load (pump) is all that's required.

However, a very complete analysis needs to be performed before you run
out and buy stuff. The trick is to determine the amount of sunshine in
your area (available from NOAA). Then you need to find a pump of the
right capacity (gallons per hour) that runs on direct currect (DC), not
alternating current (AC, like your normal house power). The combination
of the load requirements (pump wattage and current) and the amount of
sunlight will tell you how big your panel must be. In addition, you need
to determine how much battery capacity is needed to keep your pump
running during periods of no sunshine. There are a number of resources
on the web that can lead you through this analysis. A voltage regulator
is needed to ensure that you always have the right DC voltage in the
system.

If you can't find a DC pump, you can add an inverter which converts the
DC from the panel and battery to AC and use an AC pump which is more
readily available.

I have to say, however, that pumps use a lot of power when running
compared to most other solar applications. That means the panel and the
battery must be larger than you expect. In addition, if you live up
north, you may not get enough sunshine to keep the system going,
especially in the darker winter months.

On the plus side, you can reduce your power requirements by only running
the pump part of the day. There are even devices available now that let
you run off of "city" power when you can't generate enough juice
yourself and then it switches back to solar when you're recharged.
However, these dual source systems are generally fairly expensive and
intended for larger applications.

Still, I suggest you do the investigation. There's no rocket science
involved, just basic arithmetic. Get the information from the net
(search for "solar energy calculations") and and see how it comes out.
Here's a sample web site with instructions for calculating small,
medium, and large water pumping systems:

http://www.codeso.com/Calculo01E.html

Good Luck!

Michael Fermanis
New Orleans, Louisiana USA (Remove the RICE to reply)
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