Puget Sound Energy officials announced Friday the Bellevue-based utility had signed a merger agreement with a consortium of mostly foreign-based investors.

PSE, which provides electricity to Whidbey Island and much of Western Washington, said customers would benefit from the merger.

In a letter to customers posted on the PSE Website Friday, company president and CEO Stephen P. Reynolds wrote that it was “business as usual, only better.”

The merger would give the company the ability to make a needed $5 billion investment in aging infrastructure over the next five years, he wrote.

“Our employees’ focus on customer service and commitment to the local community will remain unchanged on a day-to-day basis. In the future, we will be able to meet the constantly expanding regional need for energy and do so in a way that will preserve our commitment to customers, communities and the environment,” Reynolds added. “We can move faster and with greater confidence for your benefit.”

The merger is valued at $7.4 billion.

The consortium includes Macquarie Infrastructure Partners, the Canada Pension Plan Investment Board and British Columbia Investment Management Corporation, Alberta Investment Management, Macquarie-FSS Infrastructure Trust and Macquarie Bank Limited.

PSE said the merger would not affect the utility’s current workers and management employees.

PSE’s board of directors has already approved the merger. An approval is still needed from the company’s shareholders — the company will move from a publicly traded company to a privately held utility — and the merger is also subject to approval from the Federal Energy Regulatory Commission and the Washington Utilities and Transportation Commission.

More information on the merger is available at www.pse.com.