" But would i actually do anything to capture and release wasted heat energy during lights on? "
Although ,not exactly sure why would you like such a thing ,I probably can imagine.
Just ,keep in mind ,that mj during the "dark" hours ,likes a temperature of 10 degrees C lower than the ambient temperature during photosynthesis.
Copper or aluminium are not the best materials for that job .
Probably the best material for that is ..
water ...
And then metal oxides /borides/carbonates ..Meaning
metal containing stone /rock ..
Like
granite .
But also you can use a thick chunk of
iron,steel or even better "
cast iron " (iron alloy containing 2.5% - 5% Carbon ).
The-
actual- term is
Heat Capacity or
Thermal Capacitance .
http://en.wikipedia.org/wiki/Heat_capacity
http://www.electronics-cooling.com/2003/05/thermal-capacitance/
As long as LEDS
do not radiate massive amounts of heat ,but instead they
conduct it via a heat sink ,which in turn it
convects the heat with ambient air and that air is moved away from the grow site for CO2 replenishment , I can hardly expect that LEDs or COBs would manage to heat a wet substrate or a massive chunk of granite or cast iron ...
(Fire places /stoves do use materials as such for that reason ,but then wood logs are being burned for some time ,generating temperatures over 400 C and massive amounts of energy are unleashed as heat) .
Frankly ,I do not see it happening with LEDs or COBs ..
Cheers.
