MIP, which operates within the Macquarie Infrastructure and Real Assets division (MIRA) of Australia's Macquarie Group, is using investment banks JP Morgan and Credit Suisse to help handle the sale of four plants that produce renewable energy from waste in Wales, Kent and Yorkshire.

Advisors will circulate confidential information packages to potential buyers to undertake due diligence checks on the business, which sources value at more than $600 million, in early September, the sources added.

Macquarie, Credit Suisse and JP Morgan declined to comment. Wheelabrator did not respond to a request for comment.

MIRA has $129 billion of assets under management and invests in infrastructure assets including toll roads, airports, utilities and renewables.

It bought Wheelabrator Technologies, the second-largest U.S. waste-to-energy business with 25 plants across the United States and the UK, for an undisclosed price in 2019.

At $282.2 billion, more investment went into renewables globally last year than into fossil fuel and nuclear technologies, according to research by the UN Environment Programme.

Governments and companies around the world have committed to secure renewable energy to manage costs and reduce their carbon emissions, while boosting their credentials with the general public and customers.

Two of Wheelabrator's plants for sale are in a joint venture with British renewable power generator and network operator SSE, one of which is a 300 million pound ($391 million)facility still under construction.

The assets are likely to attract the interest of private equity, infrastructure and pension funds, keen to capitalise on the steady returns that renewables generate.

($1 = 0.7670 pounds)

By Arno Schuetze and Clara Denina