For many Native Americans living on tribal reservations, electricity is considered a luxury. Derrick Terry, who grew up on the Navajo Nation, recalls the first Christmas there were lights on at his grandmother’s house.

“You see the Christmas lights in the distance, it’s like seeing that unicorn,” he explains. “It’s an indescribable feeling, I guess, when you first get electricity.”

The reservation where Terry grew up is roughly the size of West Virginia and sprawls across portions of the Four Corners region, including Arizona, New Mexico, and Utah. When Terry was a child, his family used a small 12-volt car battery to power their home. He remembers the battery would run low on power simply from watching TV or having the house lights on.

“And then what you would do is you would run back outside and you start the vehicle up so it can charge back up,” he says.

Terry, who is now the renewable energy specialist for the Navajo Tribal Utility Authority, says his experience is far from singular. In fact, the U.S. Department of Energy estimates that roughly 40% — or 18,000 Navajo homes — are without electricity.

Navajo engineer Sandra Begay-Campbell operates the Tribal Energy Program for Sandia National Laboratories in Albuquerque, N.M., and provides technical assistance to local tribes. According to Begay-Campbell, the main obstacle in electrifying Navajo homes is the steep cost of infrastructure. It can cost upwards of $50,000 to extend the power grid by a single mile.

“If you’re going to put in power poles, you’re going to have to go through really hard dirt roads, lot of rocks, maybe go over a mountain, go through a canyon,” she says.

With over half of all Navajos living at or below the federal poverty line, Begay-Campbell feels it’s a highly unrealistic expense. However, with the help of government grants, some Navajos have begun exploring a more cost-effective and sustainable option: solar power.

Leo Thompson is just one out of many Navajos who are reaping the benefits of solar power. Thompson, who lives just a half-mile from a power line on the Navajo Nation in Crownpoint, N.M., pays the Navajo Tribal Utility Authority $75 a month to rent and maintain his solar panel unit — a cost which is significantly less than running a power line.

“I used to use a generator for electricity, and the price went up so we decided to have solar power,” says Thompson, who also works as an electrician’s assistant.

So far, the Navajo Tribal Utility Authority has rented 260 solar panel units; however, given the relatively high upfront solar power cost, there is currently no funding for additional units.

“This is a perfect example of how important renewable energy and storage are to people in remote or impoverished areas. As solar cells and battery storage technologies progress, I see a great opportunity for these communities,” said Paul McKnight, owner of EFS Energy. “When the solar pioneers who have invested in these technologies are ready to upgrade their systems, the old equipment can be donated to such a cause as a sort of ‘trade-in’ program. Because of the long life of solar cells, they will still have many years of useful life in them. We have already seen this starting to happen with solar panels and with the new Tesla battery systems coming out now, the price of standard lead acid batteries should start to fall as well.”