It’s not that crazy of an idea especially in winter when SAD is worst and any extra power you waste in your house heats it so it isn’t really wasted.
One of my favorite places on earth is my marijuana grow and the incredible amount of beautiful light they grow under. I’ve contemplated a scaled down version in my house. I could grow plants all over the place under the lighting like being outside, no matter what the season.
"commercially available LED light sources (for horticultural or other applications) can be considered human safe when designed, installed and used in accordance with the applicable standards, regulations and manufacturer’s instruction"
Power waste is not an issue even in summer. Power production is driven by demand. Turn on more lights, and electricity companies will produce more electricity, and eventually they will make it cheap. Turn off the lights, and they'll do nothing because there's no demand.
It's much more complex than that because power supply is not perfectly elastic. Power companies have to commit ahead of time to a certain level of production. In that sense power production is driven by projected demand.
Power waste is an issue - at times where there is oversupply, wholesale power prices can actually go negative and at that point there is an excess of power in the network which cannot be stored and if it's not consumed will lead to electrical damage. So people actually get paid to waste power. Ever seen a sports stadium with all the lights blazing late at night even though noone is there? They are one of the groups who take advantage of negative power prices. There are also places where there are literally resistors placed along the ground to sink excess electricity (as heat) into the earth during these times.
When you say "eventually they will make it cheap" that seems likely to be a misconception also. Power production is not like manufacturing. Although innovation can lead to increases in efficiency and therefore reduced cost, inefficiency is not the limiting factor on power cost.
One of my favorite places on earth is my marijuana grow and the incredible amount of beautiful light they grow under. I’ve contemplated a scaled down version in my house. I could grow plants all over the place under the lighting like being outside, no matter what the season.