because I don't have the power of infrastructure(the grid) behind my wires, had to do tight light, as little juice use as possible. Citizens 12-12 36v light engine from Cobkits. Then I researched Meanwell led drivers to find the least draw for aprrox 50w output. I'll have 2x the light on the window grow for less than 2x the juice. 4.5 amp draw from my 12v system, 16/8, easily absorbed in the spring solar bonanza