As wind power is a fluctuating energy source, using it for green hydrogen production requires flexible, but also reliable production models. The HyBalance project uses electrolysis to transform wind energy into hydrogen on an industrial scale. The plant is engineered to have a fast reaction time as well as a stable supply flow. 

One of the key challenges in using wind power to produce green hydrogen is dealing with the fluctuating nature of wind as an energy source. Especially when scaling hydrogen production to an industrial scale, hydrogen suppliers must develop flexible and reliable production models that can circumvent the uncertainty.  

The HyBalance project in Hobro uses Power-to-X technology to transform wind energy into hydrogen via electrolysis. There are two main commercial electrolysis technologies today: alkaline and PEM (proton exchange membrane) electrolysis.  

Alkaline technology has been used for many decades in industry to generate hydrogen in large quantities and can be considered a very mature technology. PEM technology is more recent and is characterised by a higher efficiency (more hydrogen produced per kWh of electricity), a smaller footprint (more kg of hydrogen produced per m³ of cell stack) and better capability to operate under flexible operations. These characteristics make PEM technology an excellent candidate to balance renewable power, and the PEM technology presents a high cost reduction potential through mass production. In the HyBalance project, the PEM electrolyser enables generation of 230 Nm³/h of hydrogen (+/- 500 kg/day).  

The general aims of the HyBalance project was to demonstrate the highly dynamic operation of the PEM electrolyser to provide grid balancing services, a high efficiency over long time duration and a high level of availability (thanks to a dual cell-stack design). The technology can help balance the electricity grid and the hydrogen can be used for clean transportation and industrial purposes. 

Importantly, the production model was engineered to have a fast reaction time, securing reliability and flexibility. Production can ramp up and down in under 10 seconds, demonstrating how hydrogen production can help balance the electricity grid. The project is strategically located in close proximity to relevant hydrogen end-users in high value markets, such as industry, hydrogen-refuelling stations for fuel cell cars and -buses and salt caverns for hydrogen storage. 

Denmark is in ideal site for solutions like the Hybalance Project. With ambitious climate goals and some of the best wind conditions in the world, the plan is for wind energy to make up a very large part of the energy mix in Denmark by 2050. According to Energinet.dk, the western part of the Danish electricity system produced more wind power than the total consumption in Western Denmark in 2015 for an annual total of 1,460 hours (16%). This situation makes the storage of wind energy very relevant, and hydrogen can play a pivotal role here.  

In the grander scheme, the project is a technology showcase for sustainable development pathways in Europe. For this reason, HyBalance received both European and Danish support through the Fuel Cells and Hydrogen 2 Joint Undertaking and the Danish EUDPprogram.  

With a 1.2 MW electrolyser capacity, the hydrogen produced in the HyBalance project can supply a fleet of more than 800 fuel cell electric vehicles (FCEV) and could contribute up to 0.5 per cent of the GHG reduction targets of the Danish transport sector.  When the project was concluded in October 2020, it had delivered 120 tonnes of hydrogen. Air Liquide continues to operate the site and produce hydrogen to supply its customers. 

The results from the HyBalance project shows that it is possible to store fluctuating renewable energy in the form of green hydrogen on a large scale, while delivering a stable, continuous supply of hydrogen to different end-users.  Results like these are paramount in realizing a future where green hydrogen production can reliably take place on an industrial scale and power zero-emission transportation.  But it doesn’t stop there. Getting to a place of commercialised large-scale hydrogen production will open many doors beyond securing hydrogen for mobility. For example, the hydrogen can be further processed into methanol or ammonia which can be used for agriculture and green production more generally. In other words, Hydrogen can be considered as the Lego brick in the energy system of the future, opening up a world of possibilities.