Hello. As a memorial I am trying to build a light-sensitive unit that will make an LED continuously glow at night. I want to put this in an extremely remote place and be reasonable confident that it will continue to operate indefinitely. The idea is that once it becomes dark, a photodiode will permit current to flow through the LED until dawn. Once the sun rises, a solar cell will recharge the battery. I want the circuit to be able to continue doing this without any component replacement or repairs for as long as possible (greater than five years would be ideal). Is this a feasible idea? What parts would you recommend? I need a rechargeable battery that can last an extremely long time (is there a way to substitute a capacitor?). I also need a somewhat reliable LED and solar panel. The longer the circuit can last, the better- it will be exposed to the elements, but I plan on encasing as much of the circuit as possible in resin. I am not concerned with cost. Also, if anyone has a decent circuit schematic for this sort of setup, I would appreciate it. I have a few, but options are always nice. Thank you for any advice.