John's Corner

Wind and Solar Generation Meet Peak Load

February 6th, 2019 12:30 am | by John MacCormack Ph.D. P.Eng. | Posted in Uncategorized

Over the last week Alberta experienced an annual peak demand of 11,401 MW on February 1, 2019 between 5 and 6 pm. It is instructive to see how wind and solar generation responded.

Over the year we expect wind generation to produce between 32% and 35% of its installed capacity. In the last week the average output of the wind generation has been 24.8% of the installed capacity. However, the PSTI AGT page shows us that during the peak load hour less than 7% of the 1445 MW of installed wind generation was being produced.

Wind Generation over Peak Load

Over a year we expect solar generation to produce on average between 18% and 19% of its installed capacity. However, the long nights and short days have reduced the average output of solar generation in the last week to just 3.9% of its installed capacity. During the system peak demand, solar generation produced nothing.

Solar Generation during Peak Load

The ability to generate during high load periods has had an effect on the average prices received by various generation types over the last week. Both wind and solar fared relatively poorly when compared to other types of dispatchable generators. As is often the case wind generation received the lowest average price for energy at $59.6/MWh. Solar did better receiving an average of $128.6 per MWh. But the real winner was imports which received an average of $262.9 per MWh. Hydro did second best at $226.2 per MWh.

Average Prices for Gen during Peak Load Week

The last week shows how the inability of solar and wind generation to respond to high load periods can play out and highlights the need for backup resources.