The Interior Department officials later Monday will announce measures they say should ultimately expedite solar energy projects on federal lands.

Although nearly 200 solar plant projects have applied for leases, none have been processed. Secretary Ken Salazar, however, has made expanding renewable energy leasing both on federal property a top priority and the announcement should help to clear the bottlenecked permitting program.

One of the initiatives proposes solar energy zones on federal lands in the Western U.S., said Serena Ingre, a spokeswoman with the Natural Resources Defense Council, or NRDC. The environmental advocacy group has been working to balance regional environmental concerns of land conservation with a federal goal of expanding renewable energy to reduce greenhouse gas emissions thought to contribute to climate change.

Many solar projects have been blocked at the local level, putting at risk the Obama Administration's plan to double renewable energy production by 2012. For example, in March, U.S. Sen. Dianne Feinstein, D-Calif., wrote to Interior Secretary Ken Salazar pledging to fight against building a solar project on 600,000 acres of federal land between the Mojave desert preserve and the Joshua Tree National Park. The area lies in a California-designated renewable zone where companies have applied to establish hundreds of solar projects.

Interior officials say that because the the solar projects are large-scale commercial activities, often requiring exclusive use of the federal lands and official land use changes, the environmental assessments and public comment processes are lengthy exercises.

Establishing solar energy zones would expedite the permitting and environmental assessment processes, describing low-conflict areas of natural resources that aren't located in proximity to wilderness areas or threatened species, said Ingre.

Companies such as First Solar (FSLR), Stirling Energy Systems, Brightsource Energy, Solel, Solar Millennium (S2M.XE), FPL Group (FPL) and PG&E (PCG) are awaiting project permit approvals.

The Interior Department isn't expected to make a final determination on renewable energy zones until later this year.

-By Ian Talley, Of Dow Jones Newswires, 202-862-9285; ian.talley@dowjones.com