Solar in BC's Climate
A solar hot water system does require the sun, and yes, even B.C.'s 'wet' coast gets enough.
Most people think that B.C. is not a good place for solar because of the weather, but this is a myth! Since the supply of solar energy comes from light generated by the sun, rather than from direct sunlight, even cloudy days can provide enough energy for up to 60 percent of domestic hot water needs. Also, our province actually gets quite a lot of sunshine, with most people in B.C. enjoying an average of 2,000 hours of sunshine per year, according to the Environment Canada Climate Weather Office. If you think of this as 12 hours of daylight per day, this is almost five and a half months of sunshine – an ample amount for solar heating to be effective. While we don’t receive the highest amount of sunshine in the world, we do have more than Germany and China, the two leading countries in solar hot water.
In Canada, there is enough solar energy to generate an average of 2500 kWh of energy per year for heating domestic hot water, which is a lot more than you’d think! In other words, a solar water heater can supplement up to half of the water heating energy needs for a typical family of four.
In Northern regions of B.C., such as Bella Coola, the sun shines for around 1,500 hours a year, while folks in Fort St. John and Dawson Creek bask in almost 2,200 sunshine hours. In Southern regions such as Victoria and Vancouver the sunshine provides roughly 2,100 hours per year.
As shown in the graph below, the average daily solar potential in Vancouver is only slightly less than that of Miami, Florida. While Miami shows greater consistency of solar potential from month to month, Vancouver has greater seasonal extremes. Taken across a whole year Vancouver’s annual daily average solar energy production is only 8% less than Miami.