11.07.13 @ 20:54
Leonardo da Vinci ABLE reports

Biogas work placement BIO4GAS part I, Bavaria, Germany 20th to the 31st May, 2013

Rhodri Hardy

I had been interested in anaerobic digestion for quite a while but It was not until got an email from the NFU that I really began to focus on this particular avenue. I began to compile my application ready for the REA. A few months later I was pleased to hear from the project supervisor that I had been accepted for the programme.

The Manufacturer BIO4GAS was interested in having me. I was very impressed with the technology used in their digesters and was happy with the offer as it seemed that their product would be suitable for our farm. My initial impression of anaerobic digestion was that it was only suitable for larger scale farms and that a Large capital investment was required. Although in many cases this is true there are a number of smaller digesters that could be adopted on farms such as ours and bio4gas represent one of these.

I was both excited and apprehensive in the build-up to the training, I had only been to Germany briefly and my grasp of the language was very basic. Upon arrival I managed to navigate myself through Munich and onto my destination for the two weeks. I had one day to adjust to my surroundings which I used to explore the area. I was interested to see that many of the roofs were covered extensively with solar panels and on a short run outside town I found two digesters on separate farms. I was able to make some comparisons to the methods of agriculture in Germany to home but there were also many differences. This made me think how compatible the technology would be for British farmers? Especially given the conditions of the previous year.

My first day was spent at the office in Kaufering everybody was very welcoming. It was arranged for me to visit two working plants near Munich one during operation and another - which was one of the prototypes was having an upgrade. This meant that the digester was to be drained and I would be able to see the inner workings of the plant. Later I chatted to one of the Founders of BIO4GAS and discussed the technology, its benefits and ease of use. We also talked about the setup of our farm and the potential for a digester. It was clear to both of us that the methods of livestock production were very different and that some additional considerations must be taken into account when designing a system for our farm. We felt that the best way to understand the process of creating a plant would be to run through some hypothetical figures.

Upon the visits to the Farms I learnt a great deal, the first farm had received one of BIO4GAS's prototype BERT digesters, as with any prototype some tweaks are needed before the optimum operating conditions are understood and reached. I stayed the night in a local hotel with Peter who was my guide and helped a great deal with some translations. I also wanted to gain a further insight into German farms and farming culture so I arranged that evening to help the Farmer with the Morning Milking which meant a 5am start the following morning. This also was beneficial in terms of understanding the how his cow stalls are designed and how this design lends itself to BIO4GAS's technology.

Work then began back on site at 8.30am I had further inspections of the digester and a developing problem was identified. Sand was beginning to build up in the base of the digester - although no immediate impact could be measured further deposits could lead to the TGL modules becoming blocked and would no longer function correctly, the sand would have to be removed. I was aware from a Biomass combustion course that silicates cause issues during combustion, many farmers have had their miscanthus crops rejected due to the presence of sand in the crop, the sand was likely to have contaminated the crops residue during harvesting which is practically unavoidable.

The 2nd digester I visited was currently operational and was recording a higher than expected output. The farmer was having problems with the Gas Engine and had to top up the oil far too regularly a MAN technician from the manufacturer was being sent out to assess the problem. Both Digesters were of the same size which was one of the smallest in bio4gas's range, the inputs per day on each were 83 and 11 m3 respectively. I found the visits very beneficial they presented me a few questions and obstacles for creating a successful plant upon our farm. It was also clear that digesters can be problematic even when the plants are less than one year old and the components are new.

The next day I was given a demonstration on how site surveys are conducted and what the optimal configuration of the site would be, these surveys form the basis of the site orientation the levels of the digester components are extremely important. I was also shown the planning guidelines for positioning of each of the components. Considerations in positioning included distance to watercourses explosion risks and most importantly the costing. This explained to me the complications of plant design. The next exercise was  related to how the initial data is collected by the sales representatives and why this data was important. Some of these questions would not be applicable to British farmers and others such as those representing legislation would need to be adjusted accordingly.

In-between training exercises I took the time to compile a folder containing useful documents related to anaerobic digestion in Britain. My colleagues were interested to hear of the availability of a payment for producing heat (RHI) as well as one for producing electricity. We compared the figures to the German scheme and it seemed that they would receive less financial support to us. I also looked at the environmental policy governing the installation of a biogas plant. Fortunately for BIO4GAS the permitting seemed to be a strait forward one, requiring only a standard permit which is a great advantage over other technologies. Reading through all the governing legislations it became apparent that there were a number of grey areas that I would have to consult with more experienced persons than I, for instance I was uncertain whether the LECs were still available for CHP? And what environmental permits would be required if energy crops were used to boost methane production? This prompted me to get in contact with Farming Connect Wales who can provide a fully subsidised meeting with a planning Advisor through Welsh Assembly Government funds, I was made aware of this service when browsing through the schemes website, and I received a prompt reply and would have to complete the necessary documents on my return to Wales.

On the Friday I started to create/edit an English PowerPoint presentation which was to be used to help expand BIO4GAS into the UK. The main issue was that there needed to be an explanation of the process of anaerobic digestion (Which I felt is still an emerging technology to British farmers.) Because BIO4GAS are yet to partner with anyone in the UK obviously the explanation of Incentives, legislation and payback was also missing. In the Afternoon I was to head out to two digesters and take Gas measurements. I was taking the measurements a liaising with the farmers and the office. We Re-visited one of the sites of the previous week and took some measurements the values for oxygen, carbon dioxide methane and Hydrogen Sulphide. All the values were at the appropriate levels and the problem with the CHP unit had been fixed.

I had very much my first week with at BIO4GAS my colleagues were very helpful and there was a great working environment in both the office and at the Biogas Plant.


Fördergesellschaft für nachhaltige Biogas- und Bioenergienutzung e.V.