A new 2-MW power-to-gas (P2G) plant inaugurated by Germany’s E.ON in late August will convert excess wind energy into synthetic natural gas that can then be fed into the regional gas grid, where it can be used to produce heat and power.
The plant in Falkenhagen, Germany, essentially uses hydrogen-electrolysis with methanization. That involves splitting water using surplus renewable energy to create hydrogen and oxygen. A chemical reaction of hydrogen with carbon dioxide generates methane—or synthetic natural gas. The Falkenhagen facility produces 360 cubic meters of hydrogen per hour, and over a 24-hour period, the facility will store about 30 MWh of energy (Figure 4).
|4. A new power-to-gas shift. E.ON and partner Swissgas in August inaugurated a new 2-MW power-to-gas plant in Falkenhagen, Germany to convert excess wind energy into synthetic gas that can be stored in the regional gas grid. Courtesy: E.ON
Canadian firm Hydrogenics Corp. provided the plant to E.ON as a turnkey project, including supply, installation, connection, and commissioning of the hydrogen production facility, consisting of gas compression, master controls, as well as a five-year service and maintenance agreement. The developer of hydrogen generation and fuel cell products is now working on a second P2G plant for E.ON in the city of Hamburg. That much-watched facility will contain the world’s single largest megawatt-scale proton exchange membrane (PEM) stack—a type of fuel cell that produces the most power for a given weight or volume of fuel cell. PEM fuel cells also have a high power density and cold-start capability. “These projects serve as a platform for upcoming Power-to-Gas facilities not only in Europe but around the world,” said Daryl Wilson, CEO of Hydrogenics in a statement.
For Germany, which is transitioning to a renewable future, the inauguration of the E.ON plant is of particular significance because it provides much-needed storage capacity to balance fluctuations in solar and wind power generation. It is also well-suited to the country’s infrastructure. Germany reportedly has a natural gas storage reservoir equivalent to more than 200 TWh.
The fledgling P2G energy storage technology, which is still relatively expensive, is strongly being promoted by Germany’s federal power and gas agency, the Bundesnetzagentur. “One of the biggest challenges of transforming Germany’s energy system is finding ways to integrate the increasing share of intermittent, renewable-source energy,” said Germany’s Economics Minister Dr. Philipp Rösler at the inauguration ceremony. “To ensure that Germany’s power system remains stable and that our economy continues to have the energy it needs, we not only have to rapidly expand energy networks but also require innovative solutions like the P2G unit here in Falkenhagen.”
The project is also supported by Swissgas, which represents more than 100 local natural gas utilities. The organization holds a 20% capital stake in the facility and an agreement to purchase a portion of the gas produced.
For more on P2G technology, see “Progress for Germany’s Power-to-Gas Drive” in POWER’s November 2012 issue.