I installed an LED shop light-worked fine for three or four hours-then flickered a few times and then nothing. I see there is no green wire in the circuit. Could that be the problem?

 

If it was an "affordable" LED light, then... you know the rest of this little rant

 

I installed an LED shop light-worked fine for three or four hours-then flickered a few times and then nothing. I see there is no green wire in the circuit. Could that be the problem?

Bring it back to the store, ask for a refund.

 

I installed an LED shop light-worked fine for three or four hours-then flickered a few times and then nothing. I see there is no green wire in the circuit. Could that be the problem?

Return it or repair it. You are probably not the first to have the problem. If deciding to repair, it isn't likely all the LEDs went out at the same time so the problem is in the power system. "Flickered" doesn't sound like a fuse. So the problem is probably in the expensive part of the power supply.
You got a make and model (so the rest of us can avoid this fate) so we might run down a schematic?

Another option. Build your own. Electronic Goldmine has a huge LED for about $15.00 that looks like it would be better output than a 100 Watt light. Runs on maybe 24 V at maybe 3 (or more) amps. Part number G21373.
I bought one but don't have it in yet. Expecting to power it by two 12 V SLA batteries. (A tad bit of a survivalist here.)
I have similar LEDs I am happy with. Heat sink is required, fan is suggested.

 

Thanks all-yes it was on the bargain table.