SCW gas is a groundbreaking technology that brings valuable things together. It is a solution for reuse of various organic waste streams. We convert these organic wastes completely into green gas and green hydrogen. Moreover, the technology works quickly, efficiently and on a large scale.

How does it work?

Water comes out of the tap as a liquid; however we also know water as a gas in the form of steam and as a solid in the form of ice. But there is also a fourth state of water: the supercritical state. Under extreme conditions (very high pressure and temperature) water acquires very special properties. This is the core of this technology.

If we mix water with organic wastes and bring it into the supercritical state, something special happens. All organic matter in the water, both recently formed organic matter and fossil-based, breaks down into gases we can put to good use: methane and hydrogen.

With the support of our partners, we have been able to develop our own research centre with reactors and advanced analysis equipment. This allows us to conduct intensive research into the processing of various waste streams and scale up the technology at the same time. Our research team now consists of more than 10 experts.

In addition to green gas and green hydrogen, green CO₂ is also released in this process. We can trap this permanently in powders that we can use in cement, for example.

Take a look at our
CO₂ CLEANUP technology

What goes into it?

We use organic wastes as the basis for SCW GAS, waste containing hydrocarbon molecules. These can be waste streams of a natural origin.

And what’s really special is that we can process a wide variety of waste streams with this technology. It can even be used for difficult, wet wastes like crude glycerol, sewage sludge, vinasse (by-product of sugar and ethanol production), organic waste, agricultural wastes and much more, wastes for which the current processing is often associated with a large carbon footprint. These feedstocks come from various sources, from household waste to industrial streams. So our technology is very versatile. What’s more, the process is fast and can be scaled up easily. And virtually all of the calorific value (energy content) of the wet wastes is converted into usable gases.

In 2019 we successfully demonstrated the entire process on an industrial scale for the first time: from feedstock mixing, conversion and gas treatment to feeding gas into the Gasunie grid (at > 70 bar). A world first! We are now focusing fully on commissioning our first industrial-scale demonstration plant in Alkmaar (approx. 20MW capacity) and on being able to process multiple waste streams.

In addition to wet organic wastes, problematic waste streams like plastic waste can also be processed. The result is ‘circular gas’: gas produced through the conversion of waste streams that originate from fossil sources like plastics and petrochemical waste for example. This is done by gasifying these wastes using supercritical water. Producing circular gas cuts carbon emissions significantly.

We believe that there is a real contribution to be made by developing innovative technologies. We are getting ever closer to scaling up the technology to an industrial level.

Gerard Essing, Founder and CEO 

What type of energy is produced?

The fuel we produce is always a mix of methane, hydrogen and CO₂ – synthetic gas, or syngas for short. We can produce a variety of end products using this syngas. In our plant in Alkmaar we convert as much of the waste as possible to green methane, which, thanks to the feedstock, we call ‘green gas’. We could however just produce green hydrogen, or a combination of green gas and green hydrogen, or green feedstock for the chemical industry.

Green gas is essentially the same as the natural gas that flows through our national gas grid. It is already widely used for heating homes and buildings, as well as a chemical building block for industry.

Gas ready for use

When our gas comes out of the plant it is already under high pressure, so it can immediately be fed into the existing pipelines – with no loss of quality or additional costs! This means that our gas can be used directly in homes anywhere in the Netherlands.

So our green gas has the potential to play an important role in the energy transition. The Netherlands intends to phase out the use of gas from the Groningen field as soon as possible. The reasons for this are clear. And yet we will still depend on gas for some time to come. With supercritical water gasification, we can quickly scale up the production of green gas and green hydrogen. Accordingly, the Dutch climate agreement states that, by 2030, the Netherlands wants to produce more than 1 billion cubic metres of gas using supercritical water gasification. That’s the equivalent of the current gas consumption of more than 800,000 homes! It’s a big challenge, and one we are taking on with a lot of energy.

The advantages at a glance:

  • it cleans up a wide variety of organic waste streams

  • this way lowering the carbon footprint of these streams

  • which are quickly and completely converted into useful substances

  • it’s an efficient process

  • that can produce green gas or green hydrogen

  • the gas can be fed directly into the existing grid

  • the technology produces reusable, green CO₂

  • it emits no harmful substances

  • it is scalable, flexible and future-proof.

Questions we commonly
get asked

Why do we still need gas?

In the Netherlands, getting the production of sustainable energy going has proved difficult.

This article tells you more.

What are sustainable gases?

When talking about sustainable gases, this generally refers to green gas or green hydrogen.

This article tells you more.

When will your technology be operational?
After building and operating various pilot installations, in 2019 we went through the entire green gas production chain for the first time on an industrial scale, from mixing the feedstocks, feeding this into the gasification chamber, conversion, gas treatment and feeding the gas into Gasunie’s national high-pressure grid. This was a key milestone, and a world first!

The experiences with testing and operating this first industrial gasifier (Model 1) and the results of research carried out by our own research centre have led to the Model 2 design. Based on the results achieved and the insights obtained, the project partners SCW and Gasunie took the decision in July 2020 to build a facility with a capacity of around 20MW. We expect to be fully operational in 2022.

Can I also invest in this?

At this stage, there is not yet an opportunity for direct private investment in SCW.

Can you process my waste too?

Right now, our research is focusing on specific waste streams we want to use when we start up the plant. Our SCW research centre can research the possibilities for processing specific industrial waste streams if a party/industry makes resources available for this.

You produce CO2. That’s bad, isn’t it?

When converting waste streams, we produce methane (which we bring up to natural gas quality), hydrogen and CO2. In Alkmaar, we use part of the CO2 in a reaction with hydrogen to produce extra methane. The CO2 that remains is green CO2 that has first been removed from the air by plants via photosynthesis. Because this is what is known as ‘short-cycle CO2’ – that’s to say it did not originate from fossil sources – you can emit this CO2 during the production of sustainable gas. We feel, however, that this is a missed opportunity to have a greater impact. We want to reuse this CO2 in our CO2 CLEANUP process and produce new valuable materials from it. With this we achieve negative emissions: we permanently capture the CO2 that has been extracted from the air by plants. In addition to these negative emissions, with our process we also avoid carbon emissions. This is because the products in which we have permanently captured CO2 replace products that currently have a high carbon footprint (like cement and concrete).

How do you cool the earth?

We use CO2 taken from the air by plants or CO2 taken from the air by direct air capture (DAC). Because we permanently capture this CO2, this reduces the amount of CO2 in the atmosphere. This is referred to as ‘negative emissions’. In addition to these negative emissions, with our process we also avoid carbon emissions. This is because the products in which we have permanently captured CO2 replace products that currently have a high carbon footprint. This ultimately achieves a double positive effect when it comes to emissions: we produce sustainable gases and at the same time contribute to cooling the earth.

Who is behind your company?

Behind our team are Gasunie New Energy, pension fund service provider PGGM and InvestNL, impact investors who want to invest in the development and roll-out of the technologies we develop with a long-term vision.

What drives you?
Making an impact! Seriously contributing to reversing global warming. As a result, we are trying to develop technologies together with our shareholders Gasunie, PGGM and InvestNL and to roll them out on a large scale as quickly as possible.

We are proud that, together with our shareholders, we have drawn up business principles where the primary objective is to achieve maximum social impact. Investing in further development and scaling up the technologies has priority over other financial indicators.

Not only are these principles set out in SCW’s articles of association, our people and our company are devoted to living up to these principles. It’s in our DNA.

News and more

Nancy Kabalt-Groot new
Supervisory board member
Check out
our cleanupdates

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