Large spreads of open land frequently separate the homes on the Navajo Reservation reservation, which covers an area of 4.8 million acres.The rambling expanses make hooking into the power grid eye-poppingly expensive. Stringing power lines costs roughly $30,000 per mile. By comparison, a one-kilowatt solar generator, which can provide for basic needs, costs roughly $10,000. The solar systems are ideal for Indian reservations because they are less expensive than power lines and don't tear up the landscape, said Gregory Kiss, president of Native American Photovoltaics, the nonprofit corporation.