This summer the construction of a new plant will start in Alkmaar that is going to produce hydrogen from digestate and sewage sludge, without using any fossil fuels or electrolysers. “We are going to show that green hydrogen really can be green and cheaper,” says managing director Bob Busser.
The Dutch government wants to make energy supplies more sustainable and replace the industrial use of natural gas with hydrogen. A wonderful but virtually unachievable goal if you ask Bob Busser. “That is to say, if you want to generate hydrogen exclusively with electricity. Wind and solar feed uncontrolled amounts of electricity into the grid, so sometimes there is too much and sometimes too little. In addition, due to grid congestion, distribution is a big challenge. Solving this is going to take at least another decade. That means there is not enough electricity available to produce hydrogen, and hydrogen is expensive.”
Hynoca (HYdrogen NO CArbon) is showing that things can be done differently. The company is going to use biomass to produce hydrogen. And no, they are not going to cut down trees to do that. Busser: “We are looking at biomass that has no other useful application.”
Solid and gaseaous mass
Hynoca has two residual flows in mind for the new plant in Alkmaar: digestate and sewage sludge that is dried and processed into pellets at waste processor HVC. The first step of the technology developed by Hynoca splits used biomass into a gaseous fraction and a solid fraction. The gaseous fraction is then cleaned in a number of steps, resulting in a special syngas, because the carbon is removed from the gas as a solid fraction.
Busser: “As a result, the syngas has a much higher hydrogen component than regular syngas. If we purify that further, so-called fuel grade hydrogen is created. There are also other alternatives. In the US, for example, we are working with LanzaJet on sustainable aviation fuel (SAF), a kind of organic kerosene. But that requires much larger volumes than what we are going to produce in Alkmaar. Industry can also apply the syngas directly.”
The solid fraction is called biochar and it contains a lot of carbon. “The biochar cannot react with oxygen for up to a hundred years, so it cannot convert to CO2,” Busser explains. Applications he sees are mainly in agriculture. “The carbon makes the soil airier and retains moisture in the upper soil layers, so you have less leaching of nutrients. In addition, the carbon is porous and provides a habitat for microorganisms which positively influences root growth.”
Local involvement
An additional benefit of capturing carbon in the soil are (voluntary) carbon credits. “Independent research (Carbon Life Cycle) shows that by producing 1 kg of hydrogen we avoid 12 kg of CO2 emissions. In comparison, producing hydrogen with an electrolyser results in 2 kg of CO2 emissions per kg of hydrogen, despite being produced with 100% green electricity.”
The construction of the plant in Alkmaar is expected to start next summer, and production starting a year later. The goal is to produce 30 kg of hydrogen per hour. “Those are relatively small quantities,” agrees Busser. “But with this project we mainly want to demonstrate the potential of this technology and that we can produce hydrogen cheaper than with electrolysers.”
Delivery to NXT filling station
Hynoca will initially work with waste wood. Experience has already been gained with this in aerospace in France, which, according to Busser, helps to start up the installation in a predictable manner. Once the production process is stable, it will be switched to digestate and sewage sludge. Contacts are also ongoing for the use of other residual flows, such as bulb waste and roadside grass. “The region offers plenty of opportunities to process local waste streams.”
Part of the hydrogen Hynoca produces will be delivered to the adjacent fuelling station of NXT. The rest will be sent to two other customers by tube trailer. The plant that Hynoca is going to build in Alkmaar is part of the European REFORMERS program. The goal of this program is to realize a smart energy hub where it is possible to still provide customers with sufficient energy while using less energy. “Hydrogen is part of that. With our hydrogen and the related CO2 savings, we are going to help make this project energy neutral.”
Header photo: A delegation from REFORMERS visiting the Hynoca project in France.
