"Oregon utilities asked to plan for flexible power resources to back up renewables"
As utilities add more wind power to their portfolios the Oregon Public Utilities Commission wants more planning for backup power.
By Lee van der Voo, Sustainable Business Oregon contributing writer
Oregon utilities are poised to roll up sleeves on a new question: how much “flexible capacity” do they need with wind turbines spinning intermittently and solar panels subject to rolling clouds?
First, here's a translation of the term.
"(Flexible capacity) is generating capacity that you can turn off as needed to address the ups and down of wind,” said Adam Bless, a utility analyst at the Oregon Public Utility Commission.
Such flexible power usually comes from thermal-powered sources: natural gas-fired power plants, coal-burning plants and nuclear power — sources that can power down when wind, solar and water resources are high.
An assessment of how much renewable power fluctuation is expected — day-to-day, hour-to-hour — along with a tally of flexible assets available to balance them hasn’t yet been done.
The issue reared its head in an unlikely venue. Over the last several months, as the PUC probed what looked like an unrelated topic — whether to allow utilities to provide chargers for electric vehicles — the EV charging question ignited talk about whether battery-powered vehicles could be a help to utilities looking to either ramp up power or store it when the wind blows and sun shines, or doesn’t.
"The comments that we had on the record convinced us that vehicle-to-grid (storage) is still a decade away," said Bless.
Yet with renewable power sources expanding, Bless said PUC staff pushed for, and got, a requirement that utilities start looking at how much intermittent power they need to integrate in the coming years, and what resources they have to balance it.
Right now, there’s no requirement that utilities balance their own wind, either by purchasing flexible capacity or building it into their power mix. And no one is saying that utilities might next be tasked with balancing their own resources either.
"We are requiring them to forecast their need for flexible generation and inventory their need for flexible generation, but there is no prescription” on how to address it, Bless said.
All three utilities in the PUC’s service territory — Portland General Electric, Pacific Power and Idaho Power –were planning to begin the inquiry alongside typical planning for power generation in their Integrated Resource Plans.
Steve Corson, spokesman for PGE, said planning for flexible generation is not unique — it’s been happening at the utility since 2007. But unlike the new requirement to make an hourly assessment of needs, old forecasts assessed flexible capacity monthly.