Hydrogen from waste

Norbert Lümmen is an associate professor at the Department of Mechanical and Marine Engineering at the Western Norway University of Applied Sciences (HVL). On May 15, he spoke about hydrogen production from waste.

The transport sector in Norway has a lot of potential to contribute to the reduction of fossil fuel use. Many companies and public transport operators have plans to make a transition from mainly Diesel-powered vehicles to the use of either electric, hybrid or hydrogen-powered vehicles in the near future.

In addition, a company could choose to only use hydrogen that has been produced from renewable sources. This puts electrolysis driven by electricity produced from renewable energy sources and the gasification of biomass in focus among the existing methods for hydrogen production. Both can be conducted without the use of fossil fuels.

With regard to the desired implementation of a circular economy, where use of new materials and primary energy should be reduced to a minimum and sourced locally, the question arises, how much of the hydrogen needed for future transport solutions in Western Norway can be produced from available sources in the Bergen region?

In his presentation, Norbert looked into the potential of hydrogen production from municipal solid bio-waste by gasification and from electrolysis driven by energy recovered from waste heat available at BIR’s local waste incineration plant in Rådalen, Bergen.

BIR’s incineration plant has a capacity for 210 000 tonne of waste per year. The energy released in this combustion is used to produce high temperature and pressure steam, which is run through a turbine to generate electricity. The rejected heat can then be fed to the district heating network. During winter mode the plant generates 8 MW of electricity and 55 MW of district heat, while in the summer the plant generates 16 MW of electricity and 15 MW of district heat. Due to the lower demand of district heat in the summer, 32 MW of useful energy is wasted.

Norbert explained two different processes from which hydrogen could be produced using excess heat and waste in the incineration plant. Further details on these two processes can be found in Norbert’s presentation below.

1. Use excess heat to produce electricity for hydrogen production by electrolysis
   • Electricity from waste heat during summer mode by means of an organic Rankine cycle
   • Use of auxiliary electricity during winter mode to have year-round hydrogen production
2. Use wet organic waste fraction as fuel for hydrogen production by gasification
   • The total amount of waste that can be handled by the incineration facility increases with new process for organic waste
   • The heating value of incinerated waste improves when wet organic fraction is removed

Through the bio-waste-gasification up to 2700 tonne of hydrogen could be produced, while the waste-heat driven electrolysis could yield up to 345 tonne. This could prove to make a considerable contribution to fossil fuel reduction in the transport sector in Hordaland, and several hydrogen ferries and fast passengers boats could be supplied with hydrogen from waste. The costs of producing this hydrogen is comparable to known costs for the different methods, but with high total capital investments especially for biomass gasification.¨

Learn more in Norbert’s presentation below