Some of the most promising areas in New Mexico for geothermal power are in the Santa Fe National Forest near the Valles Caldera National Preserve.

The Forest Service has launched a yearslong process to determine where companies can explore and potentially build utility-scale geothermal power plants in the Jemez Mountains. The plants generate electricity by recirculating water heated by the earth’s core to turn turbines. The Santa Fe National Forest and the Bureau of Land Management, which oversee geothermal leases on all federal lands, are hosting a public meeting at 5 p.m. Tuesday to discuss the geothermal leases.

Geothermal exploration will be excluded from some parts of the Jemez Mountains to protect endangered wildlife, hot springs and other protected resources. No geothermal exploration or development will be allowed, for example, in the popular 28,850-acre Jemez National Recreation Area, said forest geologist Larry Gore.

“The recreation area is not going to be touched,” Gore said. “We’ve tried to explain that, but people are still worried we’re about to sell whole Jemez to the highest bidder.”

One company, Ormat Nevada of Reno, Nev., filed notice with the BLM expressing interest in leasing 46,000 acres on the north and northwest side of the Valles Caldera for geothermal energy exploration and development. The land is part of 195,000 acres within the Santa Fe National Forest that has “significant geothermal potential,” according to the U.S. Geological Survey.

Ormat is a one-stop shop geothermal company that develops, builds, operates and owns geothermal power plants around the world. But if the Forest Service eventually approves of leasing some of the land near the Valles Caldera for geothermal development, Omart might not be interested in the leases.

The Bureau of Land Management is in charge of the geothermal leases, but the Santa Fe National Forest has to determine what areas can be leased. The Santa Fe National Forest has to first prepare an environmental assessment about the potential impacts of leasing the land for geothermal development. The EIS will include public comments received by the Forest Service through June 12.

The agency plans to complete the geothermal environmental review by November 2016. It will take several more months after that to review the leasing plans to make sure nothing was missed, Gore said.

If the Forest Service approves the leasing plans, BLM will hold a competitive bid, officials said. Companies that win the leases will have to go back to the Forest Service to have individual geothermal projects approved.

“It’s a long process and it’s all driven by economics,” Gore said.

New Mexico has vast potential, as do many Western states, for generating mass amounts of clean, renewable energy from geothermal projects. Large tracts of land were leased by companies in the 1970s and early 1980s for geothermal development, but few projects emerged, according to research by James C. Witcher of New Mexico State University. So far, greenhouses, tilapia farms and hot springs bathers have made the most use of the state’s geothermal resources.

Sheila Mallory, BLM’s deputy state director for mineral development in New Mexico, said geothermal is a great renewable source. “Typically, a power plant lasts 50 years,” she said.

Dry geothermal plants, like the ones proposed for the Jemez Mountains, inject water into a well that is heated from rocks deep underground. The hot water is collected and used to turn a turbine before being re-injected. It is a closed loop system, where the same water is heated repeatedly,” Gore said.

Geothermal plants produce electricity all the time. They have to be placed near a transmission grid to make use of the electricity.

Still, geothermal projects have met resistance. A decade ago several tribes and environmental groups opposed a geothermal power plant California’s Modoc National Forest near a lake they considered sacred. Protesters lobbied in 2013 against expanded geothermal in Hawaii. Protesters in Japan, Italy and Kenya have also protested against recent geothermal projects in their countries.

Nevada, California, Oregon and Utah remain the most “business-friendly environments” for geothermal power in the United States, according to a 2014 report from the Geothermal Energy Association.

In 2013, the 4 megawatt Dale Burgett Geothermal Plant became New Mexico’s first utility-scale geothermal plant. The plant’s second phase, the 6 megawatt Lightning Dock, is underway. Public Service Company of New Mexico is buying the Burgett energy.

Public comments on geothermal leasing in the Jemez Mountains can be faxed, emailed or mailed to the Santa Fe National Forest. Written comments may be sent via email to comments-southwestern-santafe@fs.fed.us; via fax to 505-438-5390, or via postal service to: Geothermal EIS Project, Santa Fe National Forest, 11 Forest Lane, Santa Fe, N.M. 87508.

If you go

What: Geothermal leasing in the Jemez Mountains

When: 5 p.m., Tuesday, June 2

Where: Santa Fe National Forest office, 11 Forest Lane. Off of N.M. 14, south of Santa Fe.