Dublin-based NTR said construction has already started on the 13-turbine Quixwood Moor wind farm in Berwickshire, which will generate enough electricity for about 17,000 homes.
The 27 megawatt project is due to be operational early next year, ahead of the closure of the proposed grace period for the renewables obligation subsidy scheme.
NTR chief financial officer Marie Joyce said: “We are delighted to have secured this facility with RBS, which adds to our recent successful completion of a project finance facility for our Ora More wind project in Northern Ireland.
“This facility is instrumental in ensuring the delivery of construction of this wind farm in advance of the important March 2017 deadline in the UK.”
Bruce Riley, head of project finance at RBS, said NTR was an “experienced developer of wind farms”, having built and financed more than 1.7 gigawatts of projects in Ireland, the UK and US.
He added: “We are keen to continue to support NTR in their growth aspirations on future projects. This is another important milestone for RBS in demonstrating our commitment to renewables financing.”