Hydrochar enhanced biogas production, HyBio

With new technology, we aim to explore the possibility of significantly increasing methane production during anaerobic digestion.

Recent studies have shown that hydrochar can induce biogas production when mixed with the substrate before entering the digester. In a study conducted in 2023 at Karlstad University in collaboration with C-green and Karlskoga Energy & Environment, the results showed that the methane potential increased by 90% when hydrochar produced from municipal digestate was mixed with the substrate. This novel technology now needs to be investigated with various types of substrates and hydrochars to gain a better understanding of the process.

In addition to standard batch reactor experiments, continuous trials are also planned. Through a collaborative project involving academia, local government, conversion companies, and the forest industry, a new consortium is being formed to explore the possibilities and limitations of this innovative technology.


Maria Sandberg

Karlstad University

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Project information


Karlstad University
C-Green AB
Stora Enso Skoghall Aktiebolag
Karlstad municipality

Time schedule

December 2023 - December 2025

Total cost of project

2 016 874 SEK

Swedish Energy Agency project number