* Extension runs through 2025
* Xcel to buy up to 500 MW (In U.S. dollars unless noted)
WINNIPEG, Manitoba, May 28 (Reuters) - Minneapolis-based Xcel Energy (XEL.N) and Manitoba Hydro have extended by 10 years a C$3 billion ($2.9 billion) deal for Xcel to buy power from the Canadian utility, the Manitoba government said on Friday.
The extension runs from 2015 through 2025, with Xcel buying between 375 and 500 megawatts of power from provincially owned Manitoba Hydro.
Another agreement allows for an exchange of electricity between the utilities, based on summer peak use in the United States and a winter peak in Canada.
Manitoba Hydro first agreed to sell power to Xcel Energy in the early 1970s.
The extension is subject to regulatory approval.
Xcel shares on the New York Stock Exchange were up 5 cents at $20.58 on Friday.
$1=$1.05 Canadian Reporting by Rod Nickel; editing by Rob Wilson