Green grass

Welsh scientists are working on a research project that aims to turn grass into a green transport fuel.

The £1m ’Grassohol’ research project aims to develop processes to make ethanol from perennial ryegrass – the most commonly sown grass in the UK, which is normally used for grazing or silage.

Ryegrasses with high extractable sugar contents will be used in the project, which will examine the best methods of extracting and fermenting the sugar and of maximising yields and rates of ethanol production.

The dried residue after fermentation and distillation is rich in protein and has the potential to be converted into animal feed.

One hectare of grassland could produce up to 4,500 litres of ethanol and it is envisaged that local refineries could be established on farms at a similar scale of production to wine co-operatives.

The project is led by the Institute of Biological Environmental and Rural Sciences (IBERS) at Aberystwyth University, which has incorporated the Institute of Grassland and Environmental Research.

The research includes an industrial collaboration between IBERS and two Welsh companies – Aber Instruments and the Wynnstay Group – for which the Institute has received £154,000 funding from the Welsh Assembly government’s Academic Expertise for Business (A4B) programme.

Dr Joe Gallagher from IBERS explained that biofuel production in the UK is very limited and that the bulk of bioethanol contained in transport fuels sold on UK forecourts is imported. This bioethanol is produced from food crops such as maize, wheat and sugar cane, which potentially compromises global food security.

But he said the use of ryegrass offers a far more sustainable and acceptable solution that does not compete directly with the food industry. It is cheap and easy to grow, and farmers already have the necessary expertise and equipment to manage, harvest and store grass.

He added: ’Ryegrass is ideally suited to our climate and soil conditions, its cultivation will not affect existing environmentally sensitive landscapes or biodiversity and it has a high extractable sugar content. Because of these combined properties, it offers greater potential as a feedstock for bioethanol production than many other energy crops.’

In Wales, 1.04m hectares – 62 per cent of the available land – is permanent grassland, providing a readily available resource that can be harvested over a long season.

Under the industrial collaboration, Aber Instruments will develop and adapt new equipment for monitoring the growth of yeast and other micro-organisms during fermentation, while for its part, the Wynnstay Group aims to identify suitable varieties of high-sugar ryegrass and machinery for processing the plant material.

The project forms part of a wider £1m, three-year research programme, which has received funding from DEFRA, DECC and the Biotechnology and Biological Sciences Research Council (BBSRC) via the Renewable Materials LINK programme.