Traditionally, PGE has relied on hydro resources to provide flexibility to its power infrastructure. In the past, PGE depended on contracted hydro power from the Columbia River for load-following functions, but more and more of those resources are becoming unavailable due to market reforms or are now devoted to serving local loads. Thus, new ways of achieving flexibility are needed. Due to PGE’s commitment to renewable energy and the addition of new wind and solar capacity into the system, PGE needed an efficient technology capable of quick-starting, and fast ramp-up and ramp-down rates to fulfil the grid’s need for flexibility.
In order to prepare for current and future challenges, PGE decided in February 2013 to build a 220 MW power plant adjacent to PGE’s existing natural gas-fired Port Westward and Beaver plants, located near Clatskanie in the state of Oregon. Under the name of Port Westward Unit 2, the main services of the new PGE power plant would be providing peaking power during winter and summer periods, as well as load following and renewable integration throughout the year. Yet, the most important benefit the new plant would provide PGE is to help compliance with PGE’s commitment to renewable portfolio requirements, increasing both the baseload capacity and flexible capacity at once.
“Port Westward Unit 2’s advanced technology and unique configuration allow PGE to ramp the plant up to full load in less than 10 minutes. This flexibility allows us to adjust quickly when renewable energy – like wind and solar – rise and fall with natural variability. And it also means that on peak demand days, our customers benefit from increased reliability,” says Rick Tetzloff, PGE’s project manager for the new plant.
The choice of Wärtsilä as PGE’s power plant partner was no coincidence: a Request for Proposal (RFP) was conducted pursuant to competitive bidding guidelines, in which Wärtsilä came out as the top bid by providing the best balance of cost, risk, and value while also meeting PGE’s customer needs for reliable and affordable electric power. Not only must the power plant be able to run efficiently, start fast, and ramp up and down quickly, it must also provide ancillary services, including load following, regulating margin, spinning reserve and nonspinning reserve. The Wärtsilä 50SG engine, being now the heart of PGE’s new plant, fulfils all these requirements.
The Port Westward Unit 2 power plant, equipped with 12 of the aforementioned Wärtsilä 50SG engines and its related auxiliary equipment, operates on natural gas, which became an obvious choice of fuel for PGE since the utility has access to an underground gas reservoir. The new power plant will be utilised very heavily throughout the year; making it more than merely a peaking plant. Some portion of the plant is expected to be used every week if not every day. Thus, high efficiency and reliability in line with flexibility are vital for PGE. Wärtsilä’s solution addresses these challenges and fits well into PGE’s energy generation infrastructure and portfolio.