Tribes and utilities have long struggled to provide electricity to widely dispersed residents of reservations. The Navajo Tribal Utility Authority is using photovoltaics to help solve this problem.

The Navajo Nation reservation covers parts of New Mexico, Arizona, and Utah. Between 10,000 and 30,000 Navajos living across this vast area have no electricity, making their homes even more isolated. Residents have no access to electric light, radios, televisions, and computers.

The new program will give some tribal members an opportunity to live in an electric world for the first time. NTUA is buying 200 PV systems to install at private residences. Each system will serve a single home. Utility officials have identified households to receive the units.

T-lines too costly
Jimmie Daniels, NTUA solar program manager, said the utility decided to offer this alternative power source to customers because of the prohibitive cost of stringing wire over parts of the reservation terrain. "The only way for many of these people to have electricity is to provide each household with its own photovoltaic unit," he said. That's why NTUA is investing $2 million in this PV project.

"The people are so pleased to have the units," said Sandia Engineer Marlene Brown. "Before, many of them used generators for limited power or had no power at all. Now they have power provided by a clean, quiet source."

The new program is benefiting from lessons learned during earlier PV projects on the reservation. In the early 1990s, NTUA and Sandia set up a solar electric home experiment, with a $300,000 grant from the U.S. Department of Energy aiding in the effort. This led to installation of 72 individual PV systems.

Bigger systems
"Based on results of that effort, the new systems are somewhat bigger with about 600 watts of photovoltaic collectors," said Roger Hill of Sandia's Renewable Energy Department. "They will be able to convert about 3 kilowatthours per day on average in the winter. That's enough electricity to power a single household for a day, if the family members are conservative in their use of electricity."

An earlier project had also revealed a problem with equipment failure due to lack of maintenance. The new program features a lease-purchase agreement, and NTUA performing maintenance to ensure the system keep operating. After 15 years, the customer assumes ownership and responsibility for maintaining the system.