When you think about how your electricity is generated you probably think it comes mainly from hydropower
. But did you know that Avista also uses natural gas as a fuel to generate electricity? In fact, it makes up 36% of our company owned electric power plants
. Natural gas generation is a dependable source of energy because the fuel can be stored to generate electricity anytime, and it has about half the carbon emissions of other fossil fuels, such as coal.
Avista and Portland General Electric co-own a combined cycle natural gas plant called Coyote Springs, located in Boardman, Oregon. The plant has 2 main generation units, and Avista owns Unit 2.
A combined cycle plant has a gas turbine and a steam unit all in one. These types of units are considered very efficient because they use the waste heat from the gas turbine to create steam, instead of exhausting it back into the atmosphere.
Unlike a simple cycle gas plant, which can be fired up quickly to meet the electricity generation needs of customers, the combined cycle plant at Coyote Springs is considered a “base load” facility because the natural gas generator needs to run consistently in order to provide heat for the steam generator.
Like a car, there are certain maintenance activities that need to take place after a number of years. This year, unit 2 had its first scheduled major maintenance since the unit went in service in 2002.
The project involves overhauling the natural gas and steam generators in unit 2. From start to finish, the project takes approximately six weeks to complete and a great deal of collaboration and teamwork.
The end result of the maintenance is that Unit 2 at Coyote Springs will continue to have the capacity to generate an average of 280 megawatts of power for our customers – that’s enough electricity for just over 210,000 homes.