Over the holidays I have read a lot of commentary on Alberta’s energy future. I keep seeing individuals demanding that Alberta concentrate on wind and solar for its energy future. The people making these statements are mostly activists and journalists, rather than policy types. As a numbers person, I feel it is incumbent on me to inject some actual numbers into this discussion. This blog post will explain why solar and wind, alone, can’t address Alberta’s energy needs, but rather will serve as part of a larger energy mix.
To understand this topic let’s start with some simple statistics. In 2018, Alberta’s average internal load was 9714 megawatts (MW), its winter peak demand was 11,205 MW and its summer peak demand was 11,169 MW. As for the provinces generating capacity according to the Alberta Electric System Operator on January 1, 2019 their internal capacity was:
For those wondering about the “other” it is mostly biomass with minimal solar. So currently 81% of Alberta’s capacity is made up by the combustion of fossil fuels.
Now for a quick proviso. These demand numbers are current and do not reflect any significant implementation of policies to reduce Alberta’s reliance on fossil fuels for other energy uses. If Alberta chooses to further encourage the use of electric vehicles and reduce the reliance on natural gas for heating and hot water then these demand numbers will necessarily increase substantially.
Another thing to understand about Alberta is that its electricity system is severely limited with respect to import/export capacity. It has interties in three directions: to BC, Montana and Saskatchewan. But these interties are severely limited. As described in a report from the University of Victoria:
Currently, BC and Alberta share a single transmission connection (called an intertie) with a design capacity of 1200 MW. However, due to constraints of the Alberta electricity grid, this intertie is limited to a maximum of 780 MW.
Meanwhile the intertie from from Montana is 300 MW and from Saskatchewan is only 153 MW. That means that at a maximum, Alberta can import 1250 MW. This represents less than 12% of the winter peak load (why I use winter peak will be come clear later in this article).
So here is the renewables challenge: Alberta needs to figure out how to generate nearly 11,000 MW of electricity using only renewables. Well Alberta’s geography doesn’t help it. It has a strictly limited hydro capacity, most of which has already been exploited. It has no access to tidal, wave or offshore wind which leaves: solar, wind and geothermal as its non-nuclear choices.
A further thing to understand about renewable energy generation: it is highly intermittent. There will be days when the wind blows and others when it won’t. The way to address this intermittency is two-fold: storage and redundancy. Storage is easy to understand. Energy can be stored in batteries or in facilities that rely on momentum, compression or gravity. Redundancy is the bigger consideration.
There are two critical features of redundancy: geographic and physical. With respect to physical redundancy you can overbuild solar facilities so they produce excess energy when the sun is shining to make up for the hours when the sun isn’t shining. Geographic redundancy involves building over a variety of areas with the assumption that the wind will always be blowing somewhere and it is always close to midday someplace on the planet. Unfortunately for Alberta geographic redundancy is not on their side. Consider this solar insolation map of Alberta:
As you can see, the only area where utility-grade solar makes sense is a limited geographic area south of Calgary. Unfortunately this essentially eliminates Alberta’s ability to build any significant geographic redundancy into their solar facilities.
Next let’s consider wind. Here is a map of wind capacity factors for Alberta:
Alberta has more geographic diversity for wind but most of the good spots are either in the mountains or in the windy south of the province. For cost-effective facilities it is hard to get the diversity necessary to provide good redundancy.
What does this mean from a practical perspective? Well let’s take a look at the performance of solar and wind facilities in Alberta from this past December. Here is a graph of the Alberta solar generation (next three graphs are courtesy of Reliable AB Energy)
That top line is the nameplate capacity of the facilities while the actual generation is the small peaks. As is evident from the graph, solar production this December was abysmal. As for annual numbers, the National Energy Board has calculated capacity for areas where Alberta has potential utility-scale solar and indicates the capacity factors range from 13% in Collin Lake to 18% at Peigan Timber. These capacity numbers are incredibly problematic. What they mean is that for Collin Lake if you wanted to generate 1000 MW of power you would need to build 7.7 – 1000 MW facilities. These would generate a lot of power during their good days and virtually none on their bad days.
Wind is better but still not ideal.
There are days when the wind does approach its capacity while others, where no power is generated. Overall, in 2018 the wind in Alberta operated at 32% of capacity so once again wind would only work if it was massively overbuilt.
How about the two together? On December 19th, at midday, wind and solar would have done a pretty reasonable job, but for much of December 13th Alberta essentially no electricity from its solar and wind facilities. For a more comprehensive picture lets look at February 2019 (one of the coldest Februaries on record.)
For much of the month, wind and solar capacity were near zero. No reasonable combination of wind, solar, storage and imports would have allowed Alberta to function during that month.
What this data shows is that if Alberta is going to forge a fossil fuel-free path to energy independence, wind, water and sun will simply not do the job in Alberta.
Alberta needs to look at regionally-appropriate energy alternatives. It needs to modernize its transmission system and massively upgrade its system of inter-provincial interties. While Alberta couldn’t reasonably design and build energy storage facilities capable of meeting its demand it doesn’t have to, because British Columbia has already done so through its large-reservoir hydro network.
If British Columbia and Alberta worked together they could create a system that took advantage of Alberta’s abundant wind and reasonable solar resources along with BC’s hydro and wind. The problem with BC is that it needs its hydro to operate, but if it could import from Alberta when the wind was blowing, then it could save that water behind its dams for when the wind was not blowing to sell back to Alberta.
Additionally, Alberta needs to come up with dispatcheable, fossil fuel-free power in the form of geothermal and/or nuclear power plants. I know the latter will be divisive but the alternative (letting Albertans freeze in the dark) would be more divisive. Any activist who is serious about breaking Alberta’s fossil fuel addiction needs to be working towards upgrading Alberta’s transmission system; improving its inter-provincial interties; and developing geothermal and nuclear alternatives to fossil fuels. Water, wind and sun alone will not do the job in Alberta no matter what the activists tell you.