Idaho Power plans to use less coal, more solar for 20 years

Sharon Fisher//July 8, 2019

Idaho Power plans to use less coal, more solar for 20 years

Sharon Fisher//July 8, 2019

photo of solar field
Solar fields like this one near Boise are helping Idaho Power reduce its reliance on coal-fired generation plants. Photo courtesy of the Sierra Club

Idaho Power expects to use more solar and less coal to generate electricity for the next 20 years. That’s the conclusion of the Idaho Power Integrated Resource Plan (IRP), released on July 1, which it updates every other year.

Some results were different this year, because for the first time Idaho Power used an automated tool to develop its portfolios, rather than relying on the manual process it had used in the past, said Kresta Davis-Butts, resource planning and operations hydrology senior manager for Idaho Power.

photo of kresta davis-butts
Kresta Davis-Butts

“It’s through the optimization that the resources are selected,” Davis-Butts said. “The long-term capacity expansion model optimizes what resources would fall into and out of the model.”

The result is that Idaho Power’s “preferred portfolio” of energy resources includes more solar and less coal than previous IRPs, Davis-Butts said.

photo of ben otto
Ben Otto

“Idaho Power’s 2019 Integrated Resource Plan demonstrates that replacing fossil fuels with clean energy is how to keep Idaho’s electricity affordable and reliable into the future,” said Ben Otto, energy associate for the Idaho Conservation League. “Under this plan, by 2026 IPC will exit five of the seven coal boilers they currently own and add hundreds of megawatts of clean solar power. This is a fundamental change of direction from just two years ago and shows that, despite the political rhetoric, fossil fuels are floundering and clean energy is the future.”

Idaho Power announced on March 26 a goal to provide 100% clean energy by 2045.

The 2019 Preferred Portfolio continues the trend away from existing coal units, which Idaho Power first included in the 2015 IRP with recommended early exits from Valmy units 1 and 2. The 2019 IRP recommends an additional two coal unit early exits at Jim Bridger as well as confirms the 2025 early exit date for Valmy Unit 2. Altogether, the report shows more than 1,000 MW of coal-generated power being taken offline by 2038, the report noted.

“We did see in our preferred portfolio an accelerated retirement of the two Jim Bridger coal units,” Davis-Butts said.

“Idaho Power had previously committed to exit three coal units – Boardman in 2020, Valmy No. 1 in 2019 and Valmy No. 2 in 2025,” Otto said. “The 2017 IRP assumed they would stay in the Jim Bridger coal plant for decades. This 2019 IRP makes new commitments about Jim Bridger coal, exiting one unit in 2022 and another in 2026.”

Idaho Power would be completely out of the coal-generation business by 2034, he said.

Starting in 2022, Idaho Power will also have power purchase agreements by contracting to purchase solar power from two private developers, Davis-Butts said.

“Another new thing in the 2019 IRP is Idaho Power bringing on online 120 MW of solar in 2022, with another 100 MW in 2023,” Otto said. “Importantly, this solar is not necessary to meet new demands for electricity, but rather adding to the system now displaces expensive gas-fired power. Adding solar now to keep electricity affordable is new and fundamentally different than how IPC treated solar in the past.”

As of March 31, Idaho Power had 3,595 solar photovoltaic systems with a total capacity of more than 30 MW. At that time, the company had received completed applications for an additional 436 solar PV systems, representing additional capacity of more than 7 MW.

The 2019 IRP evaluates the 20-year planning period from 2019 through 2038. During this period, Idaho Power’s load is forecasted to grow by 1% per year for average energy demand and 1.2% per year for peak-hour demand. Total customers are expected to increase from 550,000 in 2018 to 775,000 by 2038, according to the report.

Idaho Power said it anticipates adding approximately 10,900 customers each year throughout the 20-year planning period, with summer peak-hour load requirements growing nearly 50 MW per year, and the average-energy requirement growing more than 20 aMW per year.

The IRP also shows two other interesting developments for the future. One is several battery storage systems ranging from 10 to 30 MW coming online starting in 2034. Idaho Power is looking at two battery technologies — vanadium redox-flow and lithium. The model used lithium, Davis-Butts said. When the company is ready to implement batteries, it will look at the technology available at the time, she said.

“Battery storage technology is currently being adopted by utilities across the world with record-setting low prices being announced regularly,” Otto said.

Later this month, Los Angeles is expected to announce a 400 MW solar-plus-battery combination that is expected to provide 7% of the city’s electricity demand at less than 2 cents per kilowatt hour.

The other new Idaho Power effort: 5 MW “demand response” systems coming online for a number of years, totaling 50 MW, starting in 2026. As with the batteries, the model uses Idaho Power’s existing demand response programs as a model, with the details of the program to be decided later, Davis-Butts said.

“The demand response resource would be an expansion of Idaho Power’s current programs — an industry-leading irrigation program, a program for large industrial facilities and another using residential air conditioning,” Otto said. “Adding 5MW is a drop in the bucket compared to the roughly 350MW of demand response capacity IPC already operates.”

Idaho Power most recently released an IRP in June 2017.