Wind power storage generating heat, displacing diesel
By implementing a complex power management system in four Kuskokwim Bay-area communities, the team at Intelligent Energy Systems has started to employ wind power for heat, expanding the use of a renewable energy source typically limited to electric generation. Above, heating coils use excess wind power to warm ceramic bricks to provide space heating rather than burning fuel oil or diesel.
Photos/Courtesy/Intelligent Energy Systems
President Barack Obama has long touted an “all of the above” energy strategy for America. In Western Alaska, a small group of villages is putting the rhetoric to work.
By implementing a complex power management system in four Kuskokwim Bay-area communities, the team at Intelligent Energy Systems has started to employ wind power for heat, expanding the use of a renewable energy source typically limited to electric generation.
“With respect to villages in Western Alaska, renewables is not a luxury. It’s a necessity that has to be harnessed to make those villages sustainable,” said Dennis Meiners, a project manager for Anchorage-based Intelligent Energy Systems. “We’ve invested in infrastructure and this is a way to support it.”
Meiners’ team has been working to integrate wind energy into diesel-supported grids in Kwigillingok, Kongiganak, Kipnuk and Tuntutuliak — a collective population of about 1,700 residents.
The village governments formed the Chaninik Wind Group in 2005 as a way to pool resources and develop affordable energy solutions, Meiners said.
In Kwigillingok, five remanufactured 95-kilowatt Windmatic turbines not only offset the burning of diesel for Kwig Power Co., they also heat homes when the wind blows hard, as it often does in the flat, treeless region.
Common peak load from Kwig Power’s 100 customers is about 250 kilowatts, according to Kwig Power Manager William Igkurak, meaning the five turbines can supply the community’s power demand when they’re generating at peak capacity.
Currently, about 25 homes in “Kwig” have been outfitted with electric thermal storage units, Igkurak said.
The thermal storage units are metal, wall-mounted boxes filled with ceramic bricks that are heated by an electric coil. Rather than dump excess power generated by the turbines when the wind is really whipping, the electricity is diverted from the traditional grid to heat the storage units, ultimately reducing the diesel, or fuel oil, burned for heating in Kwig as well.
“This project is still in its infancy,” Igkurak said.
The hope is to grow the number of thermal storage units in the village to further maximize peak production of power, he said.
Even still, the project displaced about 25 percent of Kwig Power’s historic diesel consumption in its first year, he said.
Surplus electric heat costs about 10 cents per kilowatt-hour, or kwh, for residents with the storage units, according to Igkurak. He said the current price of diesel-generated electricity from Kwig Power is more than 60 cents per kwh.
For further efficiency, the “micro grid” is getting wind power storage in between the wind turbines and the thermal electric storage units thanks to Detroit, Meiners said.
The storage should allow the utility to shut down its fossil fuel power system when wind production meets demand.
By installing eight Chevrolet Volt lithium-ion battery packs, Kwig power will have enough storage to meet peak demand for 15 minutes, he said, enough time to fire up the diesel generators.
Thus, when the wind provides excess power it will go to the batteries first, and on to the thermal storage units only when the batteries are charged.
Lithium-ion batteries can be charged and discharged quickly and have a life many times longer than traditional lead-acid batteries when cycled properly, Meiners said. Together, the eight battery packs take up about as much space as two refrigerators, he said, while the same amount of lead-acid storage would fill a small room.
A Chevy Volt battery pack typically sells for $4,000 to $6,000 without the add-ons to adapt it to a vehicle.
The exact impact the batteries will have on ratepayers won’t be known for another six months, Meiners said, after the system has been tuned and in place some time. However, he expects it to eventually displace upwards of 50 percent of the utility’s diesel need, he said.
The wind system is down as the storage is integrated, Igkurak said, but it should be back up and running by the end of June.
Igkurak and Meiners emphasized that the wind-diesel system is a demonstration project.
“We would like to prove that the system works in our small community,” Igkurak said.
Purchasing, transporting and installing the batteries cost about $600,000, Meiners said.
The Chaninik Wind Group received a $750,000 grant from the Department of Energy in 2010 to help fund $2 million worth of energy improvements in the four villages. Contributions from numerous other sources rounded out project payment.
A classic example of the challenges of infrastructure work in rural Alaska, the batteries were shipped last August and arrived in Kwig in October, but were not able to be moved into place until late January when the region’s marshy ground finally froze, Meiners said.
Only about half of the project’s costs are in materials, Meiners said. The rest have gone to construction and transport costs to the remote area.
The turbines being used in the communities were originally used in small wind farms in California, Meiners said. Using the remanufactured mid-sized turbines was a way to save money, he said.
“Nobody’s making stuff for villages. It’s about adapting available technology to the situation. It’s not a market; it’s not something (General Electric) is going to invest in,” he said.
Despite being an experiment of sorts, Meiners said similar projects with larger turbines will likely be “pretty common” in rural areas like Western Alaska with good wind resources.
He estimates a 1-megawatt system could be installed for about $5 million. Such a system would displace about 100,000 gallons of diesel and be able to pay for itself within 10 years — a target timeline — he said. The initial operating life of a multi-use wind power system is about 25 years, he said.
Bigger turbines that push wind power capacity well past peak demand will be vital to fully realizing the benefits of wind in rural Alaska, according to Meiners.
“It’s a matter of gaining confidence that the technology is going to solve the problem and when the willingness to invest in it because we should be moving towards ways to install larger turbines in smaller villages, just like you install a hydro project,” He said. “You look at the whole community energy need. That’s the economic way to do it.”
Elwood Brehmer can be reached at firstname.lastname@example.org.