Stage prior to industrial application achieved
ZSW completes 250-kilowatt research plant for storing green electricity.
"The plant is a successful step in establishing the new
A further hurdle en route to achieving the marketability of Power-to-Gas technology
has been overcome: on 30 October 2012, the Zentrum für Sonnenenergie-
und Wasserstoff-Forschung Baden-Württemberg (Centre for Solar
Energy and Hydrogen Research, ZSW) inaugurated a research plant with a
connected electrical load of 250 kilowatts. The plant, which has been funded
by the German Federal Ministry for the Environment, Nature Conservation and
Nuclear Safety (BMU), converts green electricity into hydrogen and methane.
With a possible methane production of up to 300 cubic metres per day, it is the
largest plant of its kind worldwide and ten times more powerful than the test
plant constructed at ZSW three years ago. The scientists from Stuttgart are
therefore close to achieving the industrial application of the new electrical
Together with their colleagues from the Fraunhofer IWES research institute
and the SolarFuel company, the ZSW researchers want to continue optimising
the technology during operation. That should make it easier to scale up Power-
to-Gas plants into the 1-20 megawatt range relevant for the energy industry.
The R&D work is also concerned with assessing future storage requirements.
The 250-kilowatt plant comprises an alkaline pressure electrolyser, a methanisation
unit and a process control system for regulating the plant. "Our research
plant works dynamically and intermittently. In contrast to the first plant,
it can respond flexibly to fluctuating energy supplies from the wind and sun
and can also respond to sudden interruptions," explains Dr. Michael Specht,
head of ZSW's Renewable Fuels and Processes research department and
one of the fathers of the new technology. "That is a requirement for future energy
systems with a high proportion of renewable electricity." Another advantage
for its application is that the control and regulation technology corresponds
to the technology used by future large-scale industrial plants.
Baden-Württemberg's Environment Minister Franz Untersteller praised the
progress made with the Power-to-Gas technology: "In order to master the
challenges posed by the energy revolution, we need innovation and new technologies.
With a continually growing proportion of renewable electricity, this
also includes the research and use of storage gas. The 250-kilowatt research
plant is a successful step in establishing the new technology." In particular, the
Federal State of Baden-Württemberg as a centre of the automotive industry
can benefit from Power-to-Gas because the process also offers alternatives
for future mobility, explained Untersteller.
In 2013, the next chapter in the Power-to-Gas success story will be written in
Werlte in Lower Saxony. On behalf of Audi AG, SolarFuel is constructing a 6-
megawatt plant there with the aim of attaining the industrial application stage.
The experience gained from the ZSW's 250-kilowatt research plant will also be
incorporated into the Ingolstadt-based company's "e-gas" project.
The proportion of green electricity in the German grid is growing enormously.
That is presenting the energy system with new tasks: with a high proportion of
wind and solar energy, the electricity volume fluctuates considerably in accordance
with the weather conditions. In some regions it is already no longer
possible to feed surplus green electricity into the grid. Between 2020 and
2030, surplus electric power in the gigawatt range can be expected throughout
Germany during specific seasons.
Without long-term storage systems with high capacities, which will need to be
constructed by then, future surpluses cannot be made available to consumers
for periods when there is no wind and sun. The chemical storage media, hydrogen
and methane, provide long-term storage with large volumes. Only these
are capable of being stored for long periods and without losses, and can be
fed into Germany's large, well-developed gas grid. CHP plants, natural gas
vehicles and industry can use the renewable gas.
The research and development work on the plant is being funded by the German
Federal Ministry for the Environment, Nature Conservation and Reactor
Safety (BMU) (Funding Code 0325275A-C).
The Zentrum für Sonnenenergie- und Wasserstoff-Forschung Baden-Württemberg (Centre for
Solar Energy and Hydrogen Research Baden-Württemberg, ZSW) is one of the leading institutes
for applied research in the area of photovoltaics, renewable fuels, battery technology, fuel
cells and energy systems analysis. There are currently around 220 scientists, engineers and
technicians employed at ZSW's three locations in Stuttgart, Ulm and Widderstall.
The research areas of the Fraunhofer Institute for Wind Energy and Energy System Technology
(IWES) cover the entire spectrum of wind energy as well as the integration of renewable energies
in supply structures. Around 400 scientists, employees and students work at Fraunhofer
IWES. The IWES has been formed by combining the former Fraunhofer Centre for Wind Energy
and Maritime Technology (CWMT) in Bremerhaven with the Institute for Solar Energy Supply
Technology (ISET) in Kassel.
SolarFuel GmbH from Stuttgart develops Power-to-Gas plants for storing surplus green electricity
in the form of hydrogen and methane. The gas is stored in the existing gas grid and, by
using efficient CHP plants, can be converted back into electricity anywhere in Germany and at
any time for use in industrial and mobility-related applications. By integrating strongly fluctuating
sources such as the wind and the sun in a reliable energy supply, the technology meets an
important requirement for future energy systems.