* Reschedules Sundance 3 work to Q2/09
* Cuts 2009 net income forecast by C$0.12 to C$0.14
* Expects corresponding rise in 2010 net income
* Shares unchanged
CALGARY, Alberta, May 20 (Reuters) - TransAlta Corp (TA.TO), Canada's largest investor-owned electricity firm, said on Wednesday it plans to speed planned maintenance on its 353-megawatt Sundance 3 power plant in Alberta, a move that may cut its 2009 profit by as much as C$28 million ($24.6 million).
The company said it will advance scheduled work on the coal-fired unit to the second and third quarters of 2009, instead of the second quarter of next year, combining the shutdown with already-planned preventive maintenance.
TransAlta said it decided to move the work ahead because power prices are currently low in Alberta as the recession cuts electricity demand. Still, the shutdown will cut its net income this year by C$24 million to C$28 million, or between 12 and 14 Canadian cents per share, but boost its 2010 earnings by a similar amount.
"Combining the Sundance 3 major maintenance outage with work required this year makes economic sense," Steve Snyder, TransAlta's chief executive, said in a statement.
The shutdown will cut TransAlta's electricity production by 380 gigawatts this year, moving that output to 2010. Changing the dates of the work will cut 2009 cash flow by C$45 million to C$50 million but boost next year's cash flow by C$60 million to C$65 million because the change, the company said, will allow it to optimize its capital spending.
The company now expects cash flow from operations this year to range between C$700 million and C$800 million and forecasts it to run between C$850 million and C$950 million in 2010.
With the change in the timing of the work, TransAlta's entire fleet of power plants is expected to post average availability - a measure of how often its generating stations are operating - of between 87 to 89 percent.
TransAlta shares were unchanged at C$20.40 on Wednesday morning on the Toronto Stock Exchange.
$1=$1.14 Canadian Reporting by Scott Haggett and John McCrank; editing by Peter Galloway