The British fund management company invests in solar projects on behalf of investors in some of its venture capital trusts, enterprise investment schemes and inheritance tax services.
Over the past two years Octopus, in partnership with its in-house solar development company Lightsource, has invested more than 300 million pounds in solar energy.
Octopus secured the funding from the Royal Bank of Scotland's corporate and institutional banking operation and Dutch bank NIBC.
The firm can now refinance six solar parks in Cornwall, Nottinghamshire, Somerset and Cambridgeshire, which have capacities ranging from 1.7 to 5 megawatts.
"RBS and NIBC's facility will enable us to continue to invest in solar on behalf of our investors and to deliver returns to them while continuing to support the UK solar market," said Matt Setchell, head of solar at Octopus.
Octopus has more than 2.7 billion pounds of assets under management.
(Reporting by Nina Chestney; Editing by David Goodman)