Electric power generation sets and combined heat and power (CHP) modules with the new Series 4000 biogas engines. The units complete the biogas product portfolio of Tognum subsidiary MTU Onsite Energy GmbH Gas Power Systems at the top end of the range with an electrical output of up to 2 MW. These more powerful engines mean that operators of larger biogas plants can achieve even greater cost efficiency because, among other benefits, service and maintenance costs can be reduced in comparison with plants based on smaller engines and because superior power density reduces space requirements. In addition, plants based on CHP modules provide access to an extra 2.6MW of thermal energy.

The 8, 12, 16 and 20-cylinder versions of the Series 4000 will be covering an output range from around 770kW to 2,000kW. The new biogas engines benefit from the modular concept of the MTU Series 4000 engine. It is designed to run on either diesel or gas and can be used in a variety of configurations for more than 20 different applications. Instead of aluminum pistons, the biogas version has forged steel pistons and a different combustion chamber from the diesel models. It also has a fuller cam shape to provide longer valve opening. Because the calorific value of biogas is lower, the MTU engineers modified the valve timing and valve lift to achieve lower-emission combustion. The electrical efficiency is over 42 percent. Optional peripheral systems include exhaust treatment, formaldehyde catalytic converters adapted to standard engines, soundproof enclosures, emergency coolers and heat exchangers, and exhaust silencers. Other versions for running on sewage gas, landfill gas and other renewable gases are to be introduced.