ENMAX and Capital Power have started operations of the 800MW Shepard Energy Centre (Shepard) in east Calgary, Alberta, Canada.
The natural gas fuelled facility is ready to be connected to the provincial power grid in Alberta, the firms said.
ENMAX president and CEO Gianna Manes said: "We delivered Shepard as planned without a lost-time injury in the more than 4.3 million hours of work required to complete the project.
"With this crucial infrastructure added to Alberta’s electricity system, we will bring reliable electricity to Albertans for decades to come."
ENMAX had initially announced the project in 2007. It later turned into a joint venture as Capital Power acquired a 50% stake in it.
The power-generating centre is the largest gas-fuelled facility in Alberta, and features combined-cycle technology with dual combustion turbines.
The facility utilises the waste heat generated from each turbine for additional power generation, which makes it 30% more efficient than conventional coal-fired facilities.
It also emits less than 50% of CO2 produced by a conventional coal plant for per MWh of electricity generation.
Capital Power president and CEO Brian Vaasjo said: "We look forward to continuing to work with ENMAX to deliver Genesee 4 & 5, Alberta’s next large natural gas-fuelled generation facility near the end of the decade."