CALGARY - TransCanada Corp., known for its vast network of oil and gas pipelines, is making an entry into the solar power business with the acquisition of nine Ontario projects for a total of $470 million.

The Calgary-based company (TSX:TRP) said Tuesday it has agreed to buy the projects, with a combined capacity of 86 megawatts, from Canadian Solar Solutions Inc.

"The addition of these solar projects allows us to expand and add to our diverse power generating portfolio where a third of the power we own, or have interests in, comes from alternative or renewable energy sources," TransCanada CEO Russ Girling said in a news release.

TransCanada has large wind projects in Quebec and Maine, as well as hydroelectric operations that span New Hampshire, Massachusetts and Vermont. Many of its power plants in Canada and the United States run on natural gas, which burns cleaner than coal. It is also a partner in the Bruce Power nuclear plant on the shores of Lake Huron, which currently produces 4,700 megawatts of electricity.

All of the solar projects have 20-year power purchase agreements with the Ontario Power Authority. Once the acquisition closes, the investment is expected to be immediately accretive to earnings and cash flow.

Under the deal, each of the projects will be developed and built by Canadian Solar using their photovoltaic panels. TransCanada will buy each project after it begins commercial operation and once certain milestones have been met.

The energy giant said it expects the projects will come into service between late 2012 and mid-2013 in Ontario, where the company has become the largest independent power producer in the province.

Ontario has been moving to grow its alternative energy business — solar, wind, biomass and other fuels — as it phases out coal-fired power generation.

In a research note Tuesday, Desjardins Securities said the solar power expansion could add about $60 million in annual earnings before interest, taxes, depreciation and amortization to the company, or about one per cent of forecast profit for 2013.

"Although we view (TransCanada's) entry into the fast-growing Canadian solar power market as a positive development, based on the size of capital committed to the solar projects and the potential financial impact, we would not expect a material reaction from (its) shares," Desjardins said.

Though best known for its massive pipeline network that ships Western Canadian natural gas to markets in Canada and the United States, TransCanada has also drawn public attention for its $7.6- billion Keystone XL oil pipeline proposal.

The controversial megaproject would deliver oilsands crude from northern Alberta and new U.S. supplies to refineries along the Texas Gulf Coast. It has come under fire from environmentalists and other critics, and a regulatory decision on the pipeline has been delayed by at least a year until 2013.

Canadian Solar Inc. (NASDAQ:CSIQ) is one of the world's largest solar companies, with operations in North America, Europe, Australia and Asia.

TransCanada shares rose 41 cents to C$43.85 in afternoon trading on the Toronto Stock Exchange.

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