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| Photo by Bill Mead on Unsplash |
This article was first published in Castanet Nov 28, 2023 / 6:00 pm
When we describe the weather in BC, we have a tendency to think of rain in Vancouver. However, much of the dry interior gets ample amounts of sunlight year round. Large swaths of the southern interior receive more sunlight than Germany, where solar provides 67 GW of power, more than 12% of Germany’s total electricity. Closer to home, BC participates in an energy market which includes Washington and Oregon. According to SEIA these states, with similar climate (a dry side and a wet side) have already moved ahead with more than 1.9 GW of current and planned utility-scale solar. Today BC sells more energy than it purchases in the market but with growing demand for electricity, BC could find itself in the position of becoming a net importer of US energy.
Over the last ten years both prices and technology have changed drastically for utility-scale solar. The cost of building utility scale solar has dropped by 84% to $0.89 per watt of solar power. According to NREL solar with battery storage is now $1.67 per watt. New technology in solar panels, such as thin-film and bifacial panels, collect a wider spectrum of radiation allowing panels to absorb more energy from the sun and enabling electricity generation on even cloudy days.
The other technological improvement is the introduction of trackers. Today 90% of utility-scale solar plants are being built with trackers. When solar is installed on the south-facing side of a roof it generates maximum power at noon, when the panel directly faces the sun. Solar installed with a tracker can rotate to catch sunrise and then follow the sun throughout the day. Single axis trackers can increase the efficiency of the solar array by as much as 20%.
It is not enough to produce sufficient electricity. You also have to deliver it during the times that it is needed. Solar energy peaks during the middle of the day, which is a good match to electricity consumption for commercial enterprises. However, residential electricity use peaks at the end of the work day (four to seven PM) as people come home from work and cook, wash dishes, and do laundry. Solar installations can include battery storage, which allows the installation to store solar energy onsite and release it to match the residential need. A solar+storage installation can save excess electricity produced at noon and then deliver it for the evening surge. Advances in battery technology make it possible not only to match a later peak but also supplement electricity overnight or on cloudy days.
It is well known that creating a resilient electrical grid with variable renewable sources requires diversity -- diversity in technology and geographical diversity. Geographical diversity is obtained by spreading renewable sources over a wide area. Technical diversity can be obtained by investing in a mix of solar and wind, backed in BC by hydro power. A prime example of complementarity between solar and hydro is the 2023 drought. This summer, due to lack of rain, most of BC’s water basins are in level 4 or level 5 drought. When water is low BC Hydro cannot draw power from its smaller dams and must place more reliance on its larger assets. Solar, however, produces peak electricity during these hot dry months, relieving BC Hydro’s systems of the need to draw down their limited reservoirs. Adding a substantial amount of solar to the provincial electrical grid would make BC more resilient in climate change driven weather conditions. A study by Johannes Schmidt on Brazil, which like BC uses hydro as the main source of electricity, found grid stability was maximized at “optimal mix of around 37% of PV, 9% of wind, and 50% of hydropower generation.”
Articles and cartoons on Teaspoon Energy by Kristy Dyer are licensed under a Creative Commons Attribution-NoDerivatives 4.0 International License You may reprint this as-is for free.
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