Sludge2Energy: Unlocking Clean Energy and Biochar from Dried Sludge Through Pyrolysis

The Sludge2Energy project uses a pyrolysis process to convert waste into energy-rich gases and biochar by heating dried sewage sludge in a low-oxygen environment. This approach transforms a disposal challenge into valuable energy and circular resources at a pilot scale.

Publication Date
13/02/2026
Reading Time
< 1 minute

Pyrolysis is a thermochemical conversion process. In simple terms, it heats an organic material at high temperature in the absence (or strong limitation) of oxygen. Because oxygen is limited, the material does not “burn” as in combustion—instead, it breaks down into different fractions.

Why sludge needs to be dried first

Sewage sludge typically contains a high amount of water. Drying reduces moisture, making the feedstock more stable and consistent and helping the conversion process run more efficiently. This is why pyrolysis in Sludge2Energy is linked to the project’s pre-treatment steps (such as solar drying).

What does pyrolysis produce?

When dried sludge undergoes pyrolysis, it can generate:

  • Energy carriers (typically a gas fraction that can be used for energy recovery, depending on the system design)
  • Biochar, a carbon-rich solid material that can potentially be valorised in circular applications, depending on quality and safety requirements

Why pyrolysis is central to Sludge2Energy

Pyrolysis supports the project’s ambition to move from “waste management” to resource recovery. By converting sludge into useful outputs, it can contribute to:

  • Reducing the amount of residual material requiring disposal
  • Improving the overall sustainability profile of sludge treatment pathways
  • Generating evidence on technical performance and operational requirements through pilot-scale testing

From concept to real-world validation

In Sludge2Energy, pyrolysis is not only described in theory: it is tested, monitored, and optimised through demonstration activities, generating practical knowledge for water utilities and local stakeholders interested in replicable solutions.

Last Update

13/02/2026