being slightly electricity illiterate i approach the more knowledge endowed members of this esteemed community… pardon the play with words, it must be the child in me
i have a small pv and a fan, see images for specs please - i want to directly connect the fan to the pv as part of a compostulator [my wife’s word] which will blow air via pipes underneath garden cuttings to speedup composting.
now it seems the pv might deliver too much electricity to the fan - can i put say tinfoil over parts of the pv to curtail power output?
in anticipation.
gabriel
EDIT, I THINK I’VE SOLVED THE PROBLEM BY COVERING PART OF THE PV TO ONLY PRODUCE 12V… A WASTE OR REALESTATE BUT COST-EFFECTIVE
I would look at a little cheap buck regulator, that has a range of dc input voltages, and the output voltage for what you need. 12v in this case, for the fan.
Just to add to what Deon has posted.
The PV panel will produce power at 18V while you are using a fan that require 12V. If the voltage is too high it will damage the fan, but there is a bit of tolerance in the fan. If the current that the PV produce is too much it is not critical as it will just not be used, but the voltage can break the fan.
The buck converter will reduce the input voltage to what you want making it safe for the fan to keep working for a long time (hopefully).
What Deon said. Likely cheapest and closest to idiot proof.
Could also go completely old-school and put in a series resistor. But it would have to be a beefy one. I expect that panel to run around 20V to 22V open circuit, so you need to burn off 10V or so, at 0.64A, that is 6.4 watts of heat to get rid of, and you need around 15Ω to drop those volts. So one of these, combined with something to sink the heat into…
