Size Matters: Fuel Cells and Electrolysers on the Power Grid
When it comes to centralised energy production, specifically electricity generation, size matters. Both fuel cells and electrolysers are vying for the opportunities available in this market, with fuel cells offering clean power generation and electrolysers providing renewable energy storage and grid stabilisation services, but what are the challenges in terms of scale, and how are they being tackled? Electrolysers and fuel cells provide different benefits, so we should consider the question for each technology in turn.
The largest nuclear and coal-fired power stations around the world have capacities in excess of 6,000 MW; the largest fuel cells manufactured commercially range from 400 kW up to 2.8 MW in size. Clearly there is a gap in terms of scale, but fuel cells do have a benefit which falls in their favour: modularity. In the Republic of Korea, POSCO Energy is building a 58.8 MW fuel cell installation, which is essentially a large number of fuel cells connected in a modular fashion. The country is interested in fuel cell technology due to incentives as part of its Renewable Portfolio Standard (RPS). The standard began in 2012, mandating that companies with generation capacity in excess of 500 MW must supply 2% from New and Renewable Energy (NRE) and the percentage increases year-on-year up to 10% NRE by 2022. Different NRE are afforded weightings under the RPS which in turn relate to financial payments as indicated in the table below.NRE weightings under the Korean RPS (Source: POSCO Energy)
Penalties can be imposed on any shortfalls, calculated on the difference between mandated generation and actual generation. Of the seven companies who fell under the auspices of the RPS in 2012, only one (Korea Hydro & Nuclear Power Co., Ltd) met the requirements; the Government is considering if infringement was due to lack of will, or simply a result of infrastructure issues, and fines will be issued as appropriate. In 2013, the requirement has increased to 2.5%, so fin