A dairy farmer in northern Germany who is producing over 250kWh of biogas is on course to achieve his five-year payback target after investing in an externally-mounted mixing system that reduces feedstock into smaller particles than standard equipment.
Bernd Wiesen, who has 110 cows at his farm in Bremerworde, uses a feedstock comprising 25% dry manure with straw, 25% grass silage and 50% maize but unlike most biogas plants that have the blend mixed first before pumping it in, Landia’s GasMix system gives him the benefit of being able to mix it inside. And for maintenance, everything can be conveniently accessed on the outside, so there are no health and safety issues with anyone required to get into the tank and no interruptions to the important gas making process.
“With GasMix, everything is so much easier for me,” said Wiesen. “I only have to spend about an hour per day operating the plant and with my computer I can see immediately how everything is working and how much power is being generated.”
From his 250kWh of biogas, Bernd earns around 18p for each kW of energy he generates. This is made up of 9p for the feed-in tariff, plus a further 6p for using the energy on his farm and supplying it (plus digestate for use as fertiliser) to his neighbour. He also receives 3p for using manure and maize that is from his own 170-hectare farm.
To move the feedstock, which includes 12 tonnes of maize and six tonnes of manure a day, the pump has to run for only five minutes an hour. Drawing sludge from the digester and then pumping it through the aspirating venturi chamber, biogas is aspirated from the top of the digester, mixed with the sludge and then injected into the tank.
Now accounting for more than 60% of his annual income, this is all a far cry from when Bernd Wiesen installed his first biogas plant back in 1995. “We knew we had to create our own electricity because oil prices kept on rising, but when we started, things didn’t smell very good at all!” he recalled. “But now my neighbours have said how very much better it is these days, which is all because of Landia’s GasMix.”
Image – Farmer Bernd with his GasMix system.
