The Calgary-owned utility lowered its monthly power price by 45 per cent for customers on its regulated rate option in southern Alberta.
Consumers will pay 6.555 cents per kilowatt hour in May, down from 11.
885 cent per kWh the previous month.
A year ago, the RRO was 6.626 per kWh in May.
Electricity prices in Alberta, Canadas only fully deregulated power market, have been volatile since two major coal-fired generators were taken off-line in December.
The 38-year-old Sundance 1 and 2 units were shut down on boiler issues owner TransAlta Corp. subsequently said were too costly to fix.
Power prices in Alberta averaged $48.52 per MWh in March, down from $122.45 per MWh in February, and $79.05 in January.
The outages of 560 megawatts of power during an extended cold spell in the province pulled up first quarter prices, and prompted analysts to bump up 2011 price forecasts.
An unexpected permanent shift in Albertas low cost generation availability has forced us to raise our power price outlook by as much as 50 per cent over the next few years, said Martin King, with FirstEnergy Capital Corp. early in April.
King upped his 2011 forecast to $66.77 per MWh, from $45.11 per MWh.