Denmark approved a plan on Thursday to build the world's first energy island, which will produce and store enough green energy to cover the power needs of three million European households. The artificial North Sea island, which in its initial phase will be the size of 18 football fields, will be linked to hundreds of offshore wind turbines and supply power to homes and green hydrogen for use in shipping, aviation, industry and heavy transport. The move came as the EU unveiled plans to change its electricity system to rely mostly on renewable energy within a decade and increase its offshore wind energy capacity 25-fold by 2050. "This is truly a great moment for Denmark and for the global green transition," Energy Minister Dan Joergensen said. "It will make a big contribution to the realisation of the enormous potential for European offshore wind. The energy island, which will cost about 210 billion Danish krone ($33.9bn) to build, is an important part of Denmark's legally binding target to cut greenhouse gas emissions by 70 per cent by 2030 from 1990 levels, one of the world's most ambitious. The Nordic country, home to wind turbine maker Vestas and offshore wind farm developer Orsted, was, with its favourable winds, a pioneer in onshore and offshore turbines, building the world's first offshore farm almost 30 years ago. In December, it decided to halt the search for oil and gas in the Danish part of the North Sea and hopes instead to make it a centre for renewable energy and carbon storage. The island, to be built 80 kilometres off Denmark's west coast, and its surrounding wind turbines will have an initial capacity of three gigawatts and be operational about 2033. Denmark also has plans for an energy island in the Baltic Sea. The state will hold a controlling stake in both islands.