Why has Yukon Energy been using thermal recently?

Some people who follow our energy consumption chart have been wondering recently, “why have you been using so much thermal these past few months?”

There are a few reasons for this. However, before we get into them, let’s celebrate that on average, over 90% of the electricity we generate comes from renewable sources. This makes the Yukon one of the top jurisdictions in renewable electricity generation in Canada. We use thermal (LNG and diesel) to ensure we have the electricity we need when there aren’t enough renewable resources available, during emergencies and during winter peaks.

In July, we had to run our diesel generators in Dawson City so that we could safely complete upgrades at our Callison substation. This meant disconnecting Dawson from the main grid and supplying electricity to Dawson residents via our diesel generators in downtown Dawson city. Having local diesel generators allows us to complete these critical projects, while still ensuring residents have the electricity they need.

In August and September, we have had to use thermal for two main reasons:

1. We have had an abnormally dry August and September

As seen in the Canadian Drought Outlook, conditions across the Yukon have ranged from abnormally dry to moderate drought. As a result of these dry conditions, our reservoir at Aishihik has not filled as quickly as it normally does. The Aishihik hydro plant plays an important role in the winter, providing approximately 40% of the electricity Yukoners need when demand for electricity is highest. It is also our primary hydroelectric facility that stores energy for use in the winter. For this reason, we have been using LNG to conserve water now, to ensure we have enough water for use in the winter. 

2. Our Mayo A hydro plant is offline

In June of this year, there was a small rockslide behind the Mayo A hydro plant. While there was no risk to public safety, out of an abundance of caution for worker safety, we made the decision to shut the Mayo A plant down. This means that electricity that would have been generated by the Mayo A plant in August and September is now being generated using LNG. We are currently working on removing the excess rock on the top layer of the slope to minimize the risk of future rockslides, and to get the Mayo A plant up and running this winter.