Solar Air Conditioner

wmoses wrote:

Golden_HVAC wrote:
However it would be just as easy to spend $1,000 on a solar system, $400 on 4 batteries, $1,200 on a good pure sine wave inverter, and be able to run the rooftop air conditioner all day long.

That is my dream one of these days - going full solar. :)

Why dream. For the cost of a tank of gas, you can buy a solar panel. I bought a pair of 10 amp solar controllers for $13 each. These are prices that where not thinkable 20 years ago. When I bought my first pair of 45 watt panels, wiring, mounts, instructions and a 15 amp controller it was $750.

Now days you can buy a 100 watt solar panel from SunElec.com for only about $100 - $120.

THe controller you can get from AliExpress.com for $13 to get a PWM 10 - 20 amp model. If you plan on installing 300 watts, get a 20 amp controller for each 250 - 300 rated watts. You can use multiple controllers in one system.

For mounts, I used 6" long 2" angle aluminum from HOme Depot, with 3 each 3/16" holes in one side to mount to the roof, another 5/16" hole for a 1/4-20 bolt to the solar panel.

WIth the 90 watt system, it was almost a requirement to tilt the panels. Once I installed a $375 75 watt panel in 1997 and a pair of $429 120 watt panels in 1999, then I no longer needed to tilt the panels. In the meantime I installed a $300 or so controller - MPPT type rated at 50 amps. I had been thinking that I might need to expand the solar system beyond 315 watts, but that is not required, unless I start using a CPAP machine. In that case, I will need more roof space for more panels.

Fred.