Abundance raised the new cash on the crowdfunding platform Seedrs.
Abundance originally targeted £1.2m from the crowd, however, due to strong investor interest, the company exceeded its target, raising £1,575,586, it said in a statement.
More than 1000 investors took part in the round, while a substantial majority of funds invested were drawn from its existing customer base, Abundance said.
Launched in 2012, Abundance has raised £82m from its customers to finance 34 green and socially useful projects through debentures in projects ranging from farm-scale wind turbines to geothermal energy to tidal energy to social housing.
Abundance co-founder and managing director, Bruce Davis, said: "Our mission has always been to help to build a more democratic and open financial system giving people control over their money. Creating an even bigger community of investors, not only in our projects but also in us, supports our work helping the transition to a cleaner, low-carbon and socially beneficial economy.”