Cogeneration, the blending technology to work at full load

ETW Energietechnik GmbH developed a new equipment that blends two gas streams of different qualities to fuel CHPs. This technology allows to calibrate the amount of biogas and natural gas to get a “homogeneous” fuel. At startups the CHP receives the perfectly balanced fuel, preventing problems caused by low CH4 concentration. That enables the operation of CHPs even with CH4 concentration lower than 30%, increasing its lifetime and availability, thus its economic feasibility. More details in the interview with Oliver Jende, Responsabile del settore vendite di ETW Energietechnik GmbH.

How does the process work?

The gas/fuel supply is composed of two parallel gas trains for Landfill gas and Natural gas respectively. After the gas trains both gases are mixed together. The dosing of Natural gas for the ideal blend is done according to the CH4 concentration in the outlet gas of the blending system.

Which gases can be blended? 

All variations of Natural and Biogas can be blended.

What are the advantages to implement this technology?

Already closed landfills struggle with shrinking gas qualities and quantities. Existing CHPs than have to be operated at reduced load or sequentially shut off when their operation becomes nfeasible. Yet, the biogas production of a landfill can hold on for many years. Enriching the “poor” biogas by blending it with natural gas enables the operation of the already existing (and financed) CHPs at full load, reducing the specific costs of cogeneration and increasing the CHP lifetime. Indeed that combination ensures energy supply of self-consumers.

Is this blending technology already tested?

Especially Landfill operators. It has been implemented in Karlsruhe where it is successfully running for 6 month.

When and in which markets will this technology be available?

This technology is available all over europe in combination with the ETW CHPs. Countries abroad upon request.

Does the technology reduce maintenance costs? How does it improve energy efficiency of CHPs? 

The ETW gas blending technology does not improve the already designed eficiency potential but enables to operate them at full load even at shrinking biogas qualities. The blender avoids the reduction of efficiency caused by an operation at a reduced load.