The £1.2 million investment, which aims to dramatically cut Aberfeldy's energy costs and greenhouse gas emissions, is part of a series of energy efficiency projects worth £5 million lined up by the GIB for distilleries around Scotland.
It comes after the bank contributed £577,000 to the £1.2m cost of installing a wood-fired boiler at the Tomatin Distillery in the Highlands last year, in what was the GIB's first investment in Scotland.
The Aberfeldy investment is similarly structured and will see the distiller, owned by Bacardi, replace its inefficient, heavy fuel oil burners with biomass boilers, with no capital investment required upfront.
The new kit will be used to produce steam, needed for several parts of the whisky-making process, and use the same technology which has been applied at Tomatin. Engineering and installation work is already underway.
Bacardi, best known for its portfolio of rum brands, estimates that the project could cut the Aberfeldy distillery's carbon footprint by 90%. This would be achieved, it is calculated, by replacing 100% of the heat currently generated from fuel oil.
Tomatin, owned by Takara Shuzo of Japan, is now on track to cut greenhouse gas emissions by 80%, according to the GIB.
Stuart Lowthian, global technical director at Bacardi, said Aberfeldy project could pave the way for "further investments in sustainable power" by the spirits giant in Scotland.
He said: "This will be our second investment in biomass solutions for energy generation in the UK.
"The first was in our Bombay Sapphire gin distillery at Laverstoke Mill and we will be following up with a similar biomass investment in our tequila distillery in Mexico later this year." Edinburgh-based GIB said the investments at Tomatin and Aberfeldy are among several it has lined up for Scotch whisky distillers, with a spokeswoman confirming a further three will be unveiled in the coming weeks.
The bank is contributing half of the funding as the cornerstone investor in £50 million Energy Saving Investments (ESI) which is managed by Equitix, the London-based fund manager. The balance is coming through private investors via the Equitix Energy Efficiency Fund (EEEF).
The projects, which allow small companies to make capital investments they would otherwise find difficult to fund, are part of a wider drive by distillers to make their operations more environmentally sustainable.
Last year commercial operations began at a biomass plant which creates power and animal feed from the by-products of the whisky-making process. The Helius CoRDe plant in Rothes is a joint venture between renewables specialist Helius Energy, the Combination of Rothes Distillers (Cord) and Rabo Project Equity BV, a division of Rabobank. Diageo, Inver House, Chivas Brothers and Edrington are among the distillers involved.