According to http://www.opg.com/power/thermal/repowering/
OPG has been exploring options to “repower” (change fuel in) some of its coal-fuelled electricity generating stations with natural gas and/or forest or agriculture-based biomass. Repowering these stations allows continued use of existing facilities owned by the people of Ontario, costs less than building new stations, reduces greenhouse gas emissions considerably, provides effective back up for growing intermittent renewable electricity sources like wind and solar and maintains employment and economic benefits in the station communities.
OPG is targeting the Atikokan Generating Station to be the first station converted to biomass fuel. Atikokan achieved full electricity output on wood pellets during tests in 2008. Successful tests have also been completed at the Thunder Bay, Lambton and Nanticoke generating stations.
OPG is moving ahead with planning and approvals for repowering Atikokan GS from coal to wood-fibre biomass in 2013.