N. Nevada prison’s power lies in wood piles

By Phoebe Sweet (contact)

Wednesday, Sept. 5, 2007 | 7:15 a.m.

Brush cleared from the Lake Tahoe Basin and lumber scraps from construction, once bound for landfills, will instead fuel a new power plant at a state prison south of Carson City.

The wood waste will be chipped and burned to provide heat and electricity to the medium-security Northern Nevada Correctional Center, which houses more than 1,200 inmates.

The 1 megawatt power plant will burn up to 4,750 pound s of wood chips per hour and produce enough electricity to power about 500 Northern Nevada homes. On average, it will meet three-quarters of the prison's power needs. When the plant generates more electricity than the prison needs at the time, the prison will sell it to Sierra Pacific Power Co.

After taking into account the plant's $8.2 million price tag, the on-site power plant will save the prison almost $9 million over 20 years.

The prison spends $400,000 a year on natural gas from Southwest Gas and $639,000 on electricity from Sierra Pacific . The biomass power plant will be paid off in 15 years and is expected to be in service for about 30 years.

Lori Bagwell, chief of fiscal services for the prison, said the biggest challenge has been finding wood to feed the burners.

Although there is a nearly unlimited supply of woody waste cleared as part of fire prevention measures in the forests of the Lake Tahoe Basin, getting it to Carson City is a challenge. Transporting brush out of forests in small vehicles or chipping on site adds to the cost of the fuel.

But construction waste is a simpler matter, coming straight from the Carson City landfill, where inmates sort the wood and pack it into a flatbed truck. It is taken to a Carson City company, where it is combined with other wood waste and chipped . The material is delivered to the prison in enclosed tractor trailer trucks and then burned to boil water and create steam, which turns a turbine to generate electricity.

"Emissions are very low. This whole plant is state of the art," said Steve Suwe, a spokesman for the Nevada Department of Corrections.

The plant includes a bag house to control emissions and an ash separator, and it will monitor the clarity of the air it emits.

The plant and its controls are contained within an 83-by-80 - foot metal building on the prison 's grounds.

Arizona company APS Energy Systems also installed 30 kilowatts of photo voltaic thin film solar laminates on the roof of the plant .