Gas from grass

[Vanden Saab]

I wasn't sure where this lived and could not find an existing thread so if it is in the wrong place or duplicate, Mods feel free to move it.
I was listening to the head honcho from Ecotricity on the radio the other morning talking about making gas from grass using some sort of anaerobic digester. It seems they have already set up a plant to provide 5,000 homes with gas using this method. The only downside seems to be that to provide enough gas for the whole country would take by my estimation 25% of all the farming land in the UK although grass can be grown on lower quality land and with the reduction in the amount of meat being eaten no doubt more grassland will be available, there can also be rotation of crops so a farm produces food in between growing grass.
I am no 'greenie' but am I missing something or could this be one of the solutions to the energy shortage and our dependence on fossil fuels which allows us to retain our gas boilers. It seems even the by-product can be used as fertilizer...

https://www.ecotricity.co.uk/our-news/2021/ecotric...