Alberta issued a request for proposals seeking enough solar-generated power to provide about 55% of the government's needs for the next two decades.

The government intends to purchase 135,000 MWh of solar electricity annually over the next 20 years. The move will allow the diversification of renewable energy sources in the province, according to an Oct. 2 statement. The government said it plans to have the contracts in place in the spring of 2019.

Alberta has aggressively sought renewable energy sources to replace its fleet of coal-fired generating plants, which is slated to be retired by 2030. The province recently awarded contracts for 600 MW of renewable electricity capacity to be added to its grid and is now soliciting 700 MW more. The bulk of Alberta's renewable energy comes from wind farms and hydroelectric projects. Solar power has been slower to catch on in the province, where winter daylight can be as brief as 7.5 hours in December. The government hopes to encourage solar generation by using it in public buildings.

"Using solar power generated in Alberta for government's electricity needs advances new economic and investment opportunities with an energy sector that is growing fast," Alberta Infrastructure Minister Sandra Jansen said in the statement. The government has obtained all of its power from renewable sources since 2009, the statement said. It started buying electricity from wind farms operated by companies like TransAlta Corp. in 2006.