S&L modernizes Lambda-1 CHP plant of the Dortmund Technical University

BHKW Uni Dortmund

Cogeneration units with Lambda-1 engines are enjoying increased popularity and regaining market share in the face of stricter exhaust emission limits and growing climate awareness.

More and more cogeneration plant operators, some of whom have been running Waukesha Lambda-1 engines for decades and often have more than 150,000 operating hours under their belt, are recognizing the advantages of modernizing their plants while retaining the engine technology - either through repair or replacement - for the next 15, 20 or 25 years.

This also applies to the Technical University of Dortmund, which has been operating 3 units with Waukesha L7042G Lambda-1 engines since 1994. Each engine with a displacement of 115 liters has an output of 670 kWm. This low specific output, combined with a speed of only 1,000 rpm, is one reason for the robustness and durability of this engine type. Although the units have a relatively modest electrical efficiency, they are characterized by a very good overall efficiency. They optimally cover the heat requirement and the contractually agreed CHP quota of the University. In addition, replacing them with lean-burn engines would necessarily require an SCR system due to the new emission limits. With the continued operation of the Lambda-1-engines in a modernized plant periphery, the emission limits of the 44th BImSchV can be complied with without any problems without additional installation and operating costs of an exhaust gas purification system. In addition, the Lambda-1 engines emit significantly less climate-impairing methane than lean-burn engines of comparable output.

Reasons enough for the Dortmund Technical University to assign S&L with the modernization of the existing plant. The first unit was already removed last year. Engine and generator were transported to the repair shop, where the engine was exchanged for a brand-new exchange engine (short block), supplemented by remanufactured components of the used engine. Meanwhile, the plant periphery and the control system were dismantled unit by unit and - while the remaining 2 units were still in operation - completely rebuilt. Currently, the first unit is being put back into operation, while the second unit is already being overhauled at the factory. The entire project is to be completed by the end of this year. Then the Dortmund Technical University can be supplied with heat and electricity for another 25 years in an environmentally friendly and climate-friendly manner.

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