I think I have discovered how to maximize winter egg production, without resorting to artificial lighting. The key I believe is to keep the chickens absolutely bone dry, but allowed to run free in a covered run that maximizes air circulation and miserly winter light. My artificial run is in two sections: The "Old Section" is about 8' x 80'. The New Section is 40' x 12'. The entire complex is roofed with metal roofing, and has held up under some pretty severe weather this winter. It is the first structure of any I have ever built! I found 300' of used 6' chain link fencing on Craigslist for $100, and then found enough used metal roofing on Craigslist to roof the entire thing for another $100. The "walls" of the runs were built with "T-Posts" and the chain link. 2x6 ceiling joists (used off Craigslist of course) Totally predator proof too. We have had weeks of below zero weather and some pretty massive snowstorms, and today it is very depressingly dark and extremely cold (our ponds are all frozen). I have a heated water supply. I just dump full bags of chicken feed on the ground, and the chickens LOVE "scratching" through the deep deep dust.