Stories & Features

Sixth turbine at Revelstoke part of plan to grow with B.C.

Several dams were designed to add capacity as B.C.'s power needs increase

At BC Hydro, we can't afford to play catch-up to the power needs of a growing province. It’s our responsibility to have generating capacity in place for when B.C.'s population and industrial growth demands more electricity.

Fortunately, we've built dams with the ability to grow over decades, and secured rights of way – carefully-planned corridors for power lines – years ahead of when we need them. And just this week, we took a big step toward adding 500 megawatts of power to a dam that first came into operation in 1984. That’s enough new electricity to power the equivalent of 40,000 homes.

BC Hydro has submitted an application for an Environmental Assessment Certificate to the BC Environmental Assessment Office to install a sixth generating unit at the Revelstoke Dam. When the Revelstoke powerhouse originally started operating in 1984, four generating units were installed, but it was designed for two more. A fifth turbine went into operation in 2010, and we're planning for the sixth to be ready by 2026 or earlier.

We did the same thing at Mica Dam and Powerhouse, located 135 km north of Revelstoke in the same Columbia River system. Originally operating with four units starting in the 1970s, Mica's generating capacity increased by 1,000 megawatts with the installation of units 5 and 6 in 2014 and 2015.

Map of BC Hydro's Columbia system dams and reservoirs
Map of BC Hydro dams and reservoirs in the Columbia River system, which supplies about 45% of B.C.'s electricity, enough to power the equivalent of 400,000 homes a year.

Even with Site C ready, we’ll need Revelstoke 6 running by 2026

We expect electricity demand will increase by almost 40% over the next 20 years, and with it, peak demand periods will require additional capacity if we’re to continue to provide reliable power on the coldest, darkest days of the year.

The way electricity demand works, not all of our generating units need to be running all the time. But there are times when we need the capacity to meet peak demand. Think of our electricity system as an eight-lane freeway that’s not always full, but has the ability to handle rush hour traffic.

We were just reminded of how B.C.'s demands are growing. During a chilly evening a few weeks ago, B.C. used more electricity than at any other time in our history.

To avoid a significant capacity deficit within the next decade, we need both Site C – which is already under construction – and Revelstoke Unit 6, in operation. If demand grows as currently forecast, Revelstoke Unit 6 will be needed in 2026 to cover a capacity deficit that will occur when we begin major maintenance work on the four 1970s-era units at Mica Dam.

Starting in 2026, the four Mica generating units will be out of service one at a time for 12 to 18 months, reducing Mica's capacity by 410 megawatts for up to six years. For contingency, BC Hydro is pursuing regulatory approval now so that Revelstoke Unit 6 could be in service even earlier, in case more capacity is needed sooner.

The Revelstoke Unit 6 project will see the addition of a new generating unit to an existing, empty bay in the Revelstoke powerhouse. The project, which is expected to cost up to $582 million, will also build a new capacitor station (which maintains voltage levels in power lines for greater system stability) 19 km west of Summerland.

We've worked closely with the Ktunaxa, Okanagan Nation, and Secwepemc on the application for Revelstoke 6, and have also been engaging with government and community members over the past three years.

"Not only does Revelstoke Unit 6 ensure that power is there for our customers during the winter season when electricity use in B.C. reaches its peak, it reflects our evolving relationships with area First Nations," said Chris O'Riley, BC Hydro’s deputy CEO and lead on capital infrastructure projects. "This is the first time that BC Hydro has partnered with First Nations on the preparation of our application for an Environmental Assessment Certificate."

A decision to issue an Environmental Assessment Certificate for Revelstoke 6 is expected in the fall of 2017.