Automation technology group ABB said it was buying renewable energy firm Power-One Inc for around $1 billion, an effort to step up its presence in the growing solar inverters market.

ABB said the boards of both companies had agreed that ABB will acquire Power-One at $6.35 per share in cash, a deal which includes Power-One's net cash of $266 million, ABB said in a statement on Monday.

The transaction would position ABB as a leading global supplier of solar inverters, the "intelligence" behind a solar photovoltaic system, ABB said.

Subject to shareholder and regulatory approvals, the transaction is expected to close the second half of 2013.

(Reporting by Silke Koltrowitz)