Biogas CHP plant cuts energy consumption by 50%

The operators of a UK combined heat and power (CHP) biogas plant report they have manage to reduce the plant’s power consumption by half.

The Agrigen-Siemens plant in Suffolk has been fitted with Siemens automation technology, including a controller, distributed I/O, and visualisation software.

The plant’s height, pressure, and temperature measurements are performed using radar level transmitters, including the Siemens Sitrans LR200, which the company says is designed for flexible continuous monitoring of liquids.

‘The optimum automation concept in combination with the patented paddle mixer has reduced the plant’s electricity consumption by 50% due to energy recovery’, Siemens says.

Austrian biopower company Thöni has supplied the plant’s biogas generator, which continuously feeds both liquid and solid material into a wet fermenter.

The material is kept moving and homogenised by specially designed paddles which prevent sediments from settling on the fermenter floor and stop suspended particles from forming floating layers.

The paddle mixers are driven by a planetary gear and frequency converter, with the smaller propeller mixers also fitted with soft starters.