Unfortunately solar has gone way up right now. $8.30 cents a watt off of e-bay is been the cheapest I've found for for the really tough cells. I've been waiting for them to go back down again and I watch vitabon's prices because he has been the cheapest I've found. I am hoping if we make a big push for solar that the cells will come down. If you find a 40 watt or greater military style for cheaper let me know, I paid $200 for mine when they were at their low.