0
\$\begingroup\$

I would like to set up something where I use a miniature solar cell (like this) to power a push solenoid (something like this), so that when light hits the cell, the solenoid pushes. I know basically nothing about engineering, but I know that the 4 watts produced by the solar cell are not enough to push a 7 watt solenoid. How could I accomplish something like this?

\$\endgroup\$
  • \$\begingroup\$ Add another power source and use the cell just for trigger (relay or something). \$\endgroup\$ – Eugene Sh. Jun 1 '16 at 20:26
1
\$\begingroup\$

It's much worse than you realize. First, the 4 you see is not 4 watts, it's 4 volts with no current. If you short-circuit the output you can get about 50 uA. Figure something on the order of 20 to 30 uA at something like 4 volts, or about 100 uW (microwatts).

There is simply no way do what you want with what you have. If you want to drive a 7 watt solenoid, you'll have to use a 7 watt solar panel. Or, if you're really desperate, you could use about 70,000 of those solar cells (I'm not recommending this, mind you, just tossing out suggestions).

If you have a separate source of power for the solenoid, you could use the solar cell to drive the gate of a power MOSFET which would turn on the solenoid, but that's really about as good as you're going to get.

\$\endgroup\$
0
\$\begingroup\$

It is easy enough to construct a solution to CONTROL a solenoid when light is detected by your miniature PV device or any other kind of light sensor. However the POWER to pull in the solenoid must have a separate and independent source.

There are hundreds of example circuits like this online showing light-sensing circuits operating relays, solenoids, motors, etc. The concept is the same for whatever kind of load.

\$\endgroup\$

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service, privacy policy and cookie policy

Not the answer you're looking for? Browse other questions tagged or ask your own question.