The funding comprises £5m in new investment from Scottish Enterprise, Scotland’s national economic development agency, and £5m from Celtic’s existing private investors, alongside £6.23m from the Grangemouth Just Transition Fund that was awarded by the Scottish Government in December.

The latest investment was announced by Scotland’s Secretary for Climate Action and Energy Gillian Martin on a visit to Celtic Renewables’ biorefinery at Grangemouth today.

Celtic Renewables will use the fresh investment to fund the planning and development of a new £120m industrial-scale biorefinery at Grangemouth with 10x the production capacity of the company’s current facility.

Celtic currently operates a commercial demonstrator biorefinery at Grangemouth. It uses ABE fermentation to produce bio-acetone, bio-butanol, and bio-ethanol from locally sourced waste and by-products including pot ale from whisky distillation and rejected potatoes.

Commenting on the news, Ms Martin said: “This investment is a clear demonstration of our commitment to securing a just transition for Grangemouth and ensuring the region remains at the heart of Scotland’s low‑carbon industrial future.

“Celtic Renewables is an outstanding example of the innovation and ambition that is driving our move towards net zero, and this further investment by Scottish Enterprise will help the company scale up, create high‑quality jobs and build new skills for the local workforce.

“During Scottish Apprenticeship Week, it is also particularly important to highlight how this package – including new support for pathways into employment – will open up opportunities for people across the area. By backing pioneering technologies and investing in our future workforce, we are laying the foundations for a more sustainable, resilient and prosperous Grangemouth.”

Celtic Renewables CEO Mark Simmers said: “Our demonstrator facility in Grangemouth is Scotland’s first biorefinery and has been operational since 2023. In that time, we’ve proven that our patented ABE fermentation process is scalable and commercially viable, de-risking future projects.

Mr Simmers continued: “Today, demand for our bio-based chemicals far outstrips current production capabilities at our demonstrator plant. Companies globally are seeking to switch to green chemicals to cut their indirect Scope 3 emissions and meet increasing customer demand for more sustainable products.

“With this latest investment, we’re now poised to take the knowledge gained at our demonstrator plant and scale to full industrial-level operations in Grangemouth.”

Scottish Enterprise chief executive Adrian Gillespie said: “Celtic Renewables is a great example of how Scottish innovation and tenacity can transform a concept into a strong commercial opportunity with significant scaling potential.

“We’ve supported the company’s growth ambitions since 2011, and it’s pleasing to see their first operational demonstrator plant here in Grangemouth as well as hearing they’re accelerating their plans for a full-scale biorefinery, which will create high-quality jobs.”

Ms Martin also used her visit to Celtic’s biorefinery to mark Scottish Apprenticeship Week and to meet the apprentices employed by Celtic Renewables who are studying at Forth Valley college.

The four apprentices are training in roles including electrical engineering, process operations and mechanical engineering while working towards their Scottish Vocational qualification. Celtic Renewables and Forth Valley College plan to expand the scheme with two new apprentice positions that are set to start this year.

Mr Simmers added: “This is the beginning of a significant new chapter for Celtic Renewables as we seek to establish Scotland as a centre for sustainable manufacturing and other breakthrough green industries.”

He explained: “With government backing, Celtic Renewables is laying down the blueprint for low-carbon chemical manufacturing in Grangemouth and in Scotland. Harnessing the area’s heritage in the in the petrochemical sector and the expertise of its workers.

“We are helping to deliver the just transition that provides certainty, long-term jobs and prosperity to the region and to all of Scotland.”

Celtic Renewables was founded in 2012 as a spinout from Edinburgh Napier University. With this latest investment, the company has secured more than £90m in total private and public funding.