When construction is complete in 2011, Oak Ridge National Laboratory’s biomass steam plant will be fueled by roughly 50,000 tons of waste wood per year. | Illustration Courtesy of Oak Ridge National Laboratory
Oak Ridge National Laboratory (ORNL) will be saving nearly $4 million a year by switching a portion of their current natural gas-fueled steam plant for one powered by biofuel. The move is part of an Energy Savings Performance Contract that will ultimately cut the Lab’s fossil fuel consumption by 70 percent per year saving 120,000 barrels of oil, the same amount used to power 4,500 homes in one year.
The plant will be constructed over 31 months, and should be completed in late 2011.
ORNL is working with energy services company (ESCO) Johnson Controls Inc. through an Energy Savings Performance Contract (ESPC). Under the contract, the ESCO conducts an energy audit and designs an energy improvement plan. The ESCO guarantees that any improvements will generate energy cost savings sufficient to pay for the project over the term of the contract.
“An ESPC is like buying a house,” says Robert Baugh, mechanical utilities facility manager at ORNL. “You get a mortgage, and you pay it off. In the case of an ESPC we pay off this work using the money from our energy savings.”
ORNL estimates the biomass plant will be repaid through savings in nearly 15 years.
60,000 pounds of steam an hour
ORNL’s steam plant was built in 1948, and by 1960, had five boilers producing steam to power the laboratory. A sixth boiler was added in the 1990s to accommodate the lab’s growth.
These boilers use oil or gas to heat water, which is converted into steam. The steam generated from this then leaves the plant through the 12 miles of steam distribution piping underneath ORNL’s campus. When the steam enters a building, it can be used for something as complicated as research applications or as simple as a space heater.
Although there are six boilers at the steam plant, not all are used for power production. Baugh explains that some boilers are there for redundancy, in case one of the primary boilers fail, there will be reinforcements.
The biomass steam plant will produce 60,000 pounds of steam an hour, and will be utilized as their base load boiler. The extra two boilers will be used to provide supplemental steam and redundancy.
From the Energy Savings Performance Contract, Oak Ridge National Laboratory will cut their fossil fuel consumption by 70 percent, which equals:
- 9,000 passenger vehicles.
- 120,000 barrels of oil.
- The energy used by 4,500 homes.
- 270 coal railcars.
The new plant will be fueled by waste woodchips. Because the plant will need around 50,000 tons of woodchips a year, ORNL will need to have multiple sources supplying the wood.
“ORNL will look to land clearers, sawmills, loggers, secondary producers, transfer stations, pallet recyclers and mulch manufacturers to outsource waste wood production,” says Baugh.
Baugh says that ORNL really began looking to replace the aging boilers when the ESPC program began. “It was the right thing to do at that time,” he says. “It’s a combination of cutting edge technology and energy efficiency. In addition to the biomass steam plant, the ESPC at ORNL will be making additional energy saving changes, like switching to energy efficient light bulbs and fixtures.”
“We’re extremely excited about the ESPC,” says Baugh. “Overall, it’s really positive.”