Van Oosten generates green energy from manure and organic waste
MAN Rollo supplies combined heat and power plants (CHPs). The efficient conversion of biogas to heat and electricity can be used for numerous applications. The CHPs are highly efficient and have low energy costs.
Henk van Oosten, owner of a mixed farm in Friesland, the Netherlands, has four CHPs that MAN Rollo supplied with MAN engines.
In 2006, Van Oosten started to ferment manure. He came in contact with MAN Rollo via the constructor of the fermentation plant, who had good experience with MAN biogas engines. Van Oosten started with one engine and currently has four. The engines easily meet Van Oosten’s expectations. “They are good, strong and reliable engines. Biogas can vary in quality, however, in spite of that our engines continue to run at least 8,000 operational hours per year,” says Van Oosten. The farm entered into a full-service maintenance contract with MAN Rollo for a period of ten years. “We are very satisfied with the service offered by MAN Rollo. Maintenance is carried out on time and professionally. And if we happen to encounter problems between services, a single telephone call is sufficient, also in the weekends. We have a good relationship with the MAN Rollo mechanics, they know all of the ins and outs.”
For the green energy he supplies, Van Oosten receives support from the SDE+ (encouraging sustainable energy) scheme. This means that he must meet various conditions. For instance, he must use the majority of the heat that is generated when fermenting manure. To do so, he built a dryer, which is equipped with an air scrubber, that dries the manure using the generated heat. The dry manure is then packed in containers and shipped to a company for further processing, which incidentally generates additional income. Most of the dry manure is intended for export.
He also uses some of the heat to heat his own home and to keep the manure in the three fermenters at a temperature of 32/36 degrees, which is a requirement of the bacterial process. In total, 80 to 90% of the heat is used.
6 million kWh per year
Van Oosten aims to achieve the highest possible conversion of biogas to electricity. He delivers over 6 million kWh per year to the grid, which is sufficient to supply energy to approximately 2,000 households per year. With the purchase of the new engine, Van Oosten expects a higher return.
He uses not only manure to produce green energy. “50% of the contents of a fermenter must be manure, we top this up with a variety of waste products from the food industry”, says Van Oosten. “This can be cocoa husks from the Verkade chocolate factory in Zaandam, products that are past their best by date, and, for instance, lemonade from the local Jumbo supermarket, weeds and stockbreeding waste. In principle, we use all organic waste, with the exception of animal offal.”
Higher efficiency and less emissions
“Van Oosten made a good choice when he decided to purchase the new MAN E2676LE biogas engine,” says Dennis van Leeuwen, Sales Manager Powergen at MAN Rollo. “The engine is efficient, gives a high return with less emissions. In view of the fact that the European standards related to permitted emission levels will be tightened up in 2017, this has been an appropriate decision. It is a more powerful engine with a higher mechanical efficiency. The E2676LE212 engine that has a capacity of 210 kWe replaces the old engine, an E2876LE (190kWe). The old engine had run for more than 90,000 hours and was at the end of its economic life. With the new purchase, he has killed two birds with one stone: the old plant has been replaced and the new plant complies with the more stringent emission legislation, also in the longer term.”
The new E2676LE can comply with the 1/2 TA Luft emission level without requiring flue gas scrubbing. This is a lower emission level than will be required in the Netherlands in 2017.
Van Oosten operates four MAN engines that vary in capacity. One of the engines generates 520 kWe and is as such the largest engine that MAN has supplied to the agricultural sector. “This 520 kWe engine and the delivery of the first E2676LE engine means that Van Oosten will have two firsts at a single location,” says Dennis van Leeuwen.
The engine will be delivered at the end of October with commissioning planned for the beginning of November.
Four engines, with generating capacities of 190, 210, 340 and 520 kWe
Input (per year): approximately 9,000 tonnes of fresh manure, 8,000 tonnes of other organic waste
Net output (per year): 6 million kWh electricity