I attended a funeral recently, of a farming neighbour who passed away at the ripe old age of 82.
The local Vicar was a great friend of Bill’s and Bill used to mow the grass around the church. One day Bill was cycling past the vicarage and the vicar was sweeping leaves outside. ‘Look at me Bill, with all my ecclesiastical training and here I am, a road sweeper.’ To which Bill replied ‘Don’t worry Vicar, I’ve been a toilet attendant to a bunch of cows for the last 60 years!’ He will be missed..

Talk turns dirty
At the wake in the village pub we were laughing at that amusing anecdote about Bill (and others that cannot be reprinted here) and talking about cow poo, as farmers do after a couple of drinks.  As farms amalgamate and herd sizes increase, the handling of waste becomes a bigger problem too. Of course you want to make use of the nutrients in manure but in Winter the land is usually too wet to get out and spread it so we have to store it somewhere. One of my neighbours is about to build a new one million litre store at quite a cost, and this seems to be a necessary trend as new anti-pollution laws are dictating how this waste is stored in order to prevent pollution of our rivers and watercourses.

However, as the saying goes, ‘one man’s cow poo is another man’s fuel’. You haven’t heard that one? Well read on.
Biogas production from farm (and other) waste is an exciting technology that seems to have a much higher uptake in some parts of the world than others. Here’s the principle – you take any type of organic waste, cow poo, food waste, plants etc, and you place it into an anaerobic digester. This is an airtight chamber, essentially the same environment as a cow’s rumen (stomach) in which the ‘digestion’ process takes place. The product of this process is biogas, which is mostly methane, and which can be either burned as gas, or used to produce electricity.

This technology has been in use in China for  over 30 years , with many  farms and rural households making this their only source of energy other than the sun. In Germany too the adoption of biogas has been promising due partly to the state’s financial support of the small scale renewables sector. In the US however uptake has been slower because the subsidies received by biogas production are a lot less that hose for wind or solar.

Why should be care what happens to our cow’s poo I hear you ask? Well there are two reasons really. Firstly it’s just an efficient way of generating energy from a fuel source that is plentiful (unlike fossil fuels). In a way you are simply harnessing the sun’s energy that was used to grow the grass that was eaten by the cow and so on and so on. Great nutrient cycling. Another important reason for supporting this type of energy generation the fact that is it mitigating some of the methane emissions that would otherwise be contributing to global warming. Finally you end up with a by-product that is a great fertiliser. Oh, and it also reduces smells which must be a good thing if you live right next to a large dairy farm!

Small biogas plants are starting to appear all over the place now, and as well as farms, communities can benefit too. By forming an energy co-operative, some small towns are taking the bull by the horns and using local food, garden, and other wastes to power biogas plants that supply gas and/or electricity to the town.  The introduction of Feed in Tariffs (FIT) here in the UK is expected to kick start many of these types of project. FITs reward small scale generation of this type by paying a guaranteed price per KWh of electricity generated, regardless of whether you use the electricity yourself. So if you are a farm for instance, you can setup a biogas plant, use the electricity generated to power the farm dairy and export any surplus to the grid. The beauty of FITs is that you get paid for everything that you generate regardless of whether you use it or not.

One Scottish farmer is already planning to power a fleet of milk delivery vehicles using electricity from his biogas plant as well as powering all of the milking equipment on the farm.
In the future I can foresee many other projects of this type on both small and large scales. It’s such a great all round technology, you never know, next time you go to turn on a light, there may just be a cow somewhere to thank for it!