North Sea renewable gas

Eleven European companies have joined forces in the North Sea Power to Gas Platform to further develop the concept of power-to-gas (P2G). P2G encompasses recent efforts to convert renewable power into gas, using Europe's existing storage and transportation system to bring that energy to market.

The European Union reports the percentage of energy from renewable sources as having risen to 13% in 2011, up from 12.1% in 2010 and 8.1% in 2004. The EU 27 members have established a "triple twenty by 2020" target, aimed at getting 20% of their power from renewables, improving efficiency by 20%, and reducing greenhouse gas emissions by 20%.

Europe's current renewable energy mix is made up of onshore (12%) and offshore wind (12%), photovoltaic solar (2.3%), concentrating solar and solar hot water (2.4%), hydro, wave, and tidal power (12%), geothermal, and biomass (almost 60%) used to generate electricity or produce biofuels. According to Eurostat figures, Estonia, whose share of renewable energy since 2011 has risen by two percentage points and stands at 14.9% of total consumption, is among the leaders to meet the EU's combined 2020 targets. The highest shares of renewables are in Sweden, Latvia, Finland, and Austria.

The fluctuating nature of power generation from wind and solar, however, makes maximizing renewables' potential contribution to the energy mix problematic, even as its supply grows. The power grid's ability to store excess energy is limited, as is its ability to move supplies from producing centers in northern Europe to consumers in the south. Renewable energy generated therefore needs either to be consumed rapidly or lost.

P2G would reduce these temporal surpluses of renewable power by using electrolysis and methanization to convert them into gases compatible with the current natural gas infrastructure. These gases could in turn be used for transportation, heating fuel, as a feedstock for the chemical industry, or burned to generate electricity anew.

The gas infrastructure can accommodate relatively large volumes of converted electricity when the supply of renewable power exceeds local grid capacity or electricity demand. Audi, which has partnered with Solar Fuel Technology GMBH & Co. KG (SFT) on a pilot P2G system, says Germany's natural gas network could hold 217 Tw-hr of electricity, compared with the power grid's 0.04 Tw-hr (OGJ, Apr. 9, 2012, p. 18).

Interested parties

The North Sea area's combination of an already well-developed onshore and offshore natural gas infrastructure and growing wind and solar power generation makes P2G particularly appealing. The combined generating capacity of offshore wind farms on the North Sea could reach around 100 Gw by 2030, according to North Sea Power to Gas Platform, while the photovoltaic (PV) capacity installed in the countries surrounding the North Sea is expected to increase from to almost 60 Gw in 2020 from 35 in 2012.

The Platform, an initiative of DNV KEMA, follows one-off initiatives like the Audi-SFT project by providing a framework for North Sea-region P2G efforts. Its international membership reflects the diversity of industries potentially affected by even the early stages of P2G: Fluxys Belgium (gas grid operator); Hydrogenics (hydrogen power); (electric and gas grid); and Maersk Oil (oil and gas production); Alliander (electric and gas grid); Gasunie (gas transmission); and TenneT (electric transmission); ITM Power (hydrogen power); National Grid UK (electric and gas grid); and Open Grid Europe (gas transmission).

The body collaborates with the European Gas Research Group (GERG), the Mediterranean Power2Gas Platform (currently being established), as well as shipping companies, NGO's, utilities, energy technology providers, transmission system operators and distribution system operators.

"The establishment of the North Sea Power to Gas Platform is an important step in the transition towards a sustainable energy system," says Lukas Grond, P2G expert at DNV KEMA and secretary of the Platform.

It's also a step being made with active participation by oil and gas companies.