Infracapital Partners LP, a European infrastructure fund run by Prudential Plc, agreed to buy with an unidentified partner a stake in Zephyr Investment Ltd., which owns wind power plants in Britain.

The accord, signed with an unidentified investment entity advised by JP Morgan & Co. is for a third of Zephyr and valued at 145 million pounds ($286 million), the seller, Englefield Capital, said today in an e-mailed statement.

Funds and private-equity firms are investing in energy and infrastructure assets because they provide a stable return. Wind- power producers get market rates for the electricity they generate and an additional financial incentive through so-called renewables obligation certificates, which they can sell separately.

``Renewable energy promises real growth potential,'' Stephen Lilley, a director in the project and infrastructure finance team at Prudential, said in the statement.

Infracapital invests in ``cash generative'' infrastructure assets, including electricity and gas-distribution networks, renewable energy and water and sewerage companies.

Zephyr has 17 wind parks in the U.K. with a combined capacity of 391 megawatts, the statement said. Other shareholders in Zephyr include RWE AG's U.K. unit and Arcapita Bank BSC.

Englefield Capital is a private equity firm with funds of 1.76 billion euros ($2.36 billion).