The family foundation of the wealthy Rockefeller dynasty has emerged as a backer of an energy project in Africa that's being spearheaded by Eddie O'Connor's Mainstream Renewable Power firm.
Last month, Dublin-based Mainstream sold a $117m stake in its African joint venture - the Lekela power platform - to investors including the World Bank.
Yesterday, Mainstream confirmed that the US-based Rockefeller Brothers Fund (RBF) had also invested in the venture as part of that stake sale.
Mainstream is investing a total of $177.5m in the Lekela platform, with $117.5m of that having been generated via the stake sale.
The funding package will enable the roll-out of 1,300 megawatts of power schemes across the African continent by 2018.
The Lekela power platform is a joint venture with Actis, a global emerging market private equity firm.
Lekela Power plans to build four more windfarms in South Africa, two windfarms and two solar plants in Egypt, and windfarms in Senegal and Ghana.
Mainstream and Lekela are aiming to help fulfil the objectives of a series of key international initiatives, including the Obama administration's Power Africa, which aims to add 30,000 megawatts of cleaner power generation through government and private partnerships, and the UN's Sustainable Energy for All, which seeks to achieve universal access to power by 2030.
Mr O'Connor - who made a fortune when he sold Airtricity to SSE in 2008 for over €1bn - said the investment by RBF is a seminal moment in the energy industry.
"The teaming up of the world's leading independent renewable power developer with a foundation started by members of the family that effectively founded the global oil industry, is a significant moment in the world's transition to a new power system based on clean energy," he said.
RBF was founded in 1940 by the sons of John D Rockefeller Jnr as a vehicle "by which they could share advice and research on charitable activities and coordinate their philanthropic efforts to better effect", according to its website.
At the end of May this year, the fund's investment assets totalled $816m (€736m).
John D Rockefeller Jnr was the only son of Standard Oil co-founder John D Rockefeller. His father became the world's richest man through his oil business, and also embarked on a philanthropic endeavour that provided the bedrock for the modern practice.
John D Rockefeller Jnr also built the famous Rockefeller Centre in New York, with construction of the huge development resulting in the iconic photo of 11 workmen sitting on a steel beam high above the city while having their lunch.
Stephen Heintz, president of the Rockefeller Brothers Fund, said he was pleased to have invested in Mainstream.
"I'm confident that if John D Rockefeller were alive today, he too would recognise the enormous opportunities in the clean energy economy and be at the forefront of the global shift to renewable resources," he said.