More capital has been raised internationally for renewable energy assets than for “conventional” energy investments this year, according to research into unlisted natural resources funds by Preqin.

It is first time that the bulk of money flowing into these funds has been directed towards green power sources, the data firm said.

Between the beginning of this year and 10 April, unlisted natural resources investment funds raised a total of $5bn (€4.4bn) of capital for renewable energy purposes, while just $2bn was raised for conventional energy, Preqin’s latest Conventional and Renewable Energy Report showed.

It said this trend looked set to continue, as there were currently more renewable energy-focused vehicles seeking investor capital, and they were targeting a higher aggregate amount of money, than conventional energy funds.

Preqin said there were currently 73 renewables-focused funds in the market targeting a combined $35bn, compared to 52 funds targeting $29bn to deploy in conventional energy.

“This may prompt more funds to take a mixed approach, investing in both renewable and conventional energy,” the data firm said, adding that this was the strategy adopted by Global Infrastructure Partners III and Brookfield Infrastructure Fund III, which were the largest infrastructure funds ever raised.

Fundraising for renewables funds was relatively constant over the past two years: $13.8bn was raised in 2015, and $12.6bn in 2016. In contrast, conventional fundraising  between the last two full years of reporting, 2015 and 2016 at  and  respectively, but fundraising for conventional energy funds fell significantly over the same period to $22.3bn in 2016, from $38.1bn in 2015.

However, Preqin said it was unlikely that this development marked a sharp shift between the strategies. More than half (52%) of investors in conventional energy also have a preference for renewables, Preqin said. In addition, 58% of renewables investors also targeted oil assets, while 61% also targeted natural gas investments.

Tom Carr, head of real assets products at Preqin, said: “Public pressure and governmental policy to address climate change has placed constraints on the fossil fuel industry, while the US shale oil boom has depressed oil prices in the mid-term. At the same time, technological breakthroughs have reduced the cost-per-unit of renewable energy sources, making them more attractive to investors.”

Both approaches are set to remain important influences on the energy market, Carr said, but he added that “the outsized dominance of conventional energy may not be as evident going forward”.