While it’s probably still true that all politics is local, all power is not. Most businesses still rely on large, central electric-generation utilities for the juice to run their operations. But that’s changing. Faced with soaring prices, a doubling of demand in recent decades, and an aging power grid susceptible to blackouts, an increasing number of small- to medium-size businesses want local control over their power supply. That can mean literally putting it in their back yards.Among the most economical, cleanest-burning and most fuel-efficient of the new power sources now emerging is the microturbine. Commercially available for only about three years, microturbines are small combustion turbines that consume natural gas or a variety of other fuels to produce 25 to 250 kilowatts of power. About as tall as a good-sized man and two or three times as wide, these compact dynamos-cousins of the engines that power jet airplanes-can be parked right next to a business facility.
Doug Herman runs a research program at the Electric Power Research Institute (a utility-funded R&D consortium) that focuses on “distributed generation”-alternative energy technologies located onsite at customer premises instead of at a centralized power plant. He says companies producing microturbines have concentrated on selling them into niche applications where customers are looking to save money on their electric bills and be assured of reliable, uninterrupted power.
Here’s how a microturbine works. First, the natural gas is first fed to a compressor, which is powered by electricity, says Gordon Savage, vice president for business development at Simmax Energy, a Huntington Beach, CA based energy systems company. About 3 kilowatts of the 80 kilowatts the microturbine generates is used to run the compressor. The compressed gas is then injected into the microturbine. This generates hot air that is then channeled through heat exchangers, Savage explains, which eventually transfer the heat to the hotel’s boilers.
Microturbines are particularly effective for slightly larger settings like manufacturing. According to mechanical engineer Bernard Kolanowski, author of the book Guide to Microturbines, hundreds can be linked to form a formidable power supply. Microturbines can also run on fuels that might otherwise be wasted. For instance, oil and natural gas are often found together when drilling takes place. To prevent an explosion, oil companies will extract and burn off the gas at a wellhead in a process called “flaring.” Microturbines can plug into the flaring pipe and run on the gas while also cutting way down on harmful hydrocarbons produced by flaring.
This is a common practice at offshore and outlying land-based oilrigs and boosting stations that lack access to power grids. The Canadian Natural Resources oil company is running five 30-kilowatt microturbines off of the natural gas flared from its Wabasca, Alberta oil well battery, according to Dan Boonstra, the authorized service provider for western Canada for Capstone Microturbines, a leading microturbine manufacturer. This station boosts natural gas from production wells down a pipeline to various utilities. The microturbines are the sole power source for the facility, which is situated out of reach of Canada’s power grid.
Microturbines are producing power at sites other than oil and gas fields, too. In most cases, the devices are deployed in cogeneration schemes to provide electricity for a facility while exhaust energy is used to heat air or water.
Take, for instance, Alloy Processing in Compton, CA-a metal plating company that anodizes components for aerospace systems. Anodizing makes parts like the bolts in an airplane wing resistant to corrosion over time. The process requires that parts be dipped in a special solution stored in huge tanks and maintained at a temperature of about 95 degrees C all day long. The amount of electricity required for this is considerable: peak electrical demand is 600 to 700 kilowatts, 300 kilowatts of which is dedicated to heating the anodizing tanks. At Alloy Processing, this resulted in monthly electric bills of $60,000 to $65,000 in the summer and $40,000 to $45,000 for the rest of the year, according to general manager and vice president Brian Leibl.