A visit to a hybrid power plant

In Prenzlau, they have electricity in bottles. And how is dena involved?

Power to Gas technology, which is being tested at the hybrid power plant in Prenzlau, could be the solution for one of the largest challenges of the energy transition: it allows green electricity to be converted into gas, thereby making it possible to store it. During a visit to the power plant, we find out how this technology works, its significance for the future of electricity supply, and what role the dena strategy platform plays in this.

If you were travelling on Brandenburg's endless roads, you might easily overlook the fact that this is where a great deal of work is being done for the future of the energy transition. Compared to the many wind power plants, the hybrid power plant near Prenzlau is rather nondescript: a simple concrete hall, three gas tanks, and two silos — from the road, it is not much larger than a typical Brandenburg farm. However, the lettering "Hybrid Power Plant" and a few painted-on water bubbles indicate that something new is indeed going on here.

“Power to Gas makes it possible to plan for the use of renewable energy.”

Jörg Müller, ENERTRAG

Since it was commissioned in the year 2011, the power plant has been the first installation in the whole of Europe which merges wind, hydrogen, and biogas — using what is called Power to Gas technology (P2G). It allows electricity from renewable sources to be converted into gas, thereby making it possible to store it. This green energy can also be utilised when the wind isn't blowing or the sun is not shining.



How does this work?

In Prenzlau, it all seems like magic. The facility premises are almost devoid of human presence, and the operational workflows are fully automated. In the interior of the central building, loud machines whine, and innumerable pipes run along the walls. Just under the ceiling hangs a transparent water tank, from which water flows into the electrolyser: two capsules which bear the symbols O2 and H2 — oxygen and hydrogen.

How the hybrid power plant works

What happens here is that electricity, which has just been generated in three wind turbines, is used to split water in an electrolytic process. The resulting hydrogen can be stored or converted back into electricity. Furthermore, the hydrogen can also be used to drive fuel cell vehicles.

The land of potential

The power plant is powered by the wind power producer ENERTRAG . Working together with the German Energy Agency (dena) as part of the Power to Gas Strategy Platform, the company is promoting the further development of this technology. The platform is operated by dena, with a total of 30 partners from industry, research, and associations.

As part of this collaboration, dena has compiled a Potentiality Atlas to research the possibilities of Power to Gas in various regions of Germany in a targeted fashion. The atlas will make it easier to find suitable locations for similar installations.

Powered by the wind

With the rapid proliferation of renewable energy, Power to Gas technology is also gaining in significance. It is central for the second phase of the energy transition, also because it signifies the coupling of many different systems. 'Not all energy which is currently being produced is required by existing electricity consumers at that very moment — but it will be needed in other sectors at a later point in time', says ENERTRAG CEO Jörg Müller. 'Hence, the aim is to use electricity produced by renewables for mobility and heat generation. That's why it will need P2G. It makes it possible to plan the use of renewable energy.'

In Prenzlau, you can observed how the generated gas can be used for mobility. Directly at the access road, an installation for filling gas canisters is currently being constructed. However, next to it is already a valve that allows large tankers to be filled with gas. These vehicles bring the hydrogen to the filling stations in Berlin and Hamburg. This green refinery can deliver 120 cubic metres of hydrogen per hour. With this quantity of hydrogen, a car could travel for 1,200 kilometres. Hence, this gas allows for environmentally friendly transportation.

“Today, over 10,000 clients of Greenpeace Energy are meeting a percentage of their heating needs with hydrogen from the Uckermark region.”

Jörg Müller, ENERTRAG

The second use of the hydrogen can be seen at the other end of the installation. Here, a silver pipe leads from the central hall to a small adjacent building. Through this pipe, which is hardly wider than a conventional heating pipe, the hydrogen is injected into the existing gas network, allowing it to be used for generating heat. 'Today, over 10,000 clients of Greenpeace Energy are meeting a percentage of their heating needs with hydrogen from the Uckermark region', says Jörg Müller from ENERTRAG. 'This is an enormous success for climate protection and shows the path we now all need to take.'

The beginnings of a new industry

In fact, the power plant in Prenzlau works entirely without the use of fossil energy sources, thereby demonstrating that a constant supply of energy from renewable sources — in this case wind energy — is indeed possible. Although the installation is only a demonstration power plant, it is special because the power plant is already a functioning business model. This is all thanks to its integrative concept. This makes the combined power plant unique for its size and versatility.

The innovative thing about the hybrid power plant is the intelligent storage and utilisation of renewable energy. Today, there are already 20 similar power plants all over Germany. This model could even become the beginning of a new, decentralised industry — with the entire value creation chain in our own country.

The future is on the horizon

The power plant in Prenzlau is a pilot project which proves that this technology works. However, the political prerequisites for efficiently implementing the energy transition still need to be met. It is exactly this which the dena strategy platform aims to change. 'The good news is that a step-by-step decarbonisation of energy production which does not involve increasing costs is possible', says Jörg Müller. 'On the contrary, we have successfully demonstrated that a needs-based energy production using fluctuating energy sources is feasible.'

Once you climb up the small hill rising up behind the machine hall of the power plant, you immediately understand the direction in which our energy supply system could develop. From here, you see a cluster of new buildings in the middle of the fields. It consists of buildings that are being supplied with energy from the hybrid power plant. It is a view that clearly illustrates two things: from a technical standpoint, the energy transition is already possible today — and there, on the horizon, lies the future.

Further information on Power to Gas is available at www.powertogas.info .

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