13 July 2022
It is apparent that global warming is resulting in more frequent and intense heatwaves in the UK. These extreme conditions cause issues for numerous industries, including renewable energy.
Many Anaerobic Digesters are prone to rapid increases in temperature as the roofs often act as thermal conductors, rapidly rising temperatures within the digesters. Unless operators are swift to react, this can raise the temperature of the substrate within the digesters and quickly upset the biology. A change of just a couple of degrees can have a dramatic impact on biology. It can take weeks to restore the biological equilibrium, resulting in crippling gas production loss and energy revenues.
In the UK, all plants are designed to be able to regulate heat through their heat exchange systems, but there is now an increasing need to have more precision control integrating chillers for extreme weather conditions.
Those plants using pre-pasteurisation or thermophilic digestion are probably more susceptible as heat is often transferred to the digesters as part of the conceptual design. Thermophilic digestion operates in a narrower range and is more sensitive to temperature changes.
Biology is not the only area of risk. Electrical components become prone to failure at higher temperatures. Air conditioning of rooms containing control panels is now a must if systems failure is to be avoided.
As an operator with a long history in successful AD operations, Agrivert has learnt to manage heat extremes at multiple plants and can offer other advice and help in managing the changing climate conditions in the UK and abroad.