The Bank, which is Japan's largest lender, regained the crown it held 2012-2014 after topping the table with $1.88 billion of financing by the end of October.

“We have long been leading the renewable energy market especially in Europe and North America,"

Yoko Yanagida, head of Power and Infrastructure at MUFG said

“In Japan, we take pride in our renewable financing which began about 15 years ago, even before the feed-in tariffs started. That allows us to attract developers and there is demand for financing."

The first and second phases of the $3.9 billion Beatrice Cape offshore wind farm was key in pushing MUFG into the top position. The bank co-financed the wind project off the northern coast of Scotland, together with around a dozen overseas banks.

MUFG is also looking to fund more clean energy projects in developing parts of Asia such as Malaysia, Thailand and India, Yanagida said.

“Renewables in Asia, outside of Japan and Australia, still have lots of room to grow,"

she said, adding that solar projects in India and Malaysia offered plenty of potential, with wind opportunities available in Thailand and Taiwan.

MUFG had about $10 billion in outstanding loans for renewable projects at the end of March. The Americas and Asia accounted for 65 percent and 20 percent of these, respectively, while the remainder was to countries in Europe, the Middle East and Africa.

A growing number of solar projects in the Middle East may also offer opportunities, Yanagida said. Elsewhere, the U.S. will remain an active market thanks to tax credit support for wind and solar.

MUFG is also looking at wind projects in Australia, with the group also wanting to add biomass and wind projects to its portfolio in Japan, where solar has dominated most of the expansion in recent years.