100 Percent Renewable? One Danish Island Experiments with Clean Power

It can seem as if the icy, cutting wind off the North Sea never stops blowing on this Danish island in winter, bending back the grass, whipping straight the flags, and setting mammoth wind turbines to their stately spinning. That's good news for Samso's 4,000 or so inhabitants, seeing as they own shares in 20 of the 21 turbines that either tower over the island or rise from the offshore waters of the Kattegat Strait, which connects the Baltic and North seas.

Some people see wind turbines as eyesores or complain about the sound of their whirring blades, but Soren Hermansen, chief proselytizer for the island's renewable energy experiment and director of the Samso Energy Academy, disagrees. "If you own a share in a wind turbine it looks better, it sounds better," he says. "It sounds like money in the bank."

The land-based turbines are 50 meters tall with blades that stretch some 27 meters from end to end. The sea-based turbines are even more massive—63 meters high (not including the spike pounded into the seafloor beneath the waves) with 40-meter blades. A single such turbine can generate roughly eight million kilowatt-hours of electricity a year at a cost of $3 million per turbine (the onshore variety are cheaper, at just over $1 million).

Drawing on a Danish co-operative tradition that stretches back 150 years to raise the cash needed to build and run slaughterhouses and other community facilities, around one in 10 "Samsingers" owns at least a share in one of the turbines, which generates an annual check based on its output and the price of electricity. The turbines also have allowed all 4,000 residents to produce more energy from renewable resources than they consume, thereby eliminating, on balance, their emissions of carbon dioxide.

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Sun, wind and wave-powered: Europe unites to build renewable energy 'supergrid'

It would connect turbines off the wind-lashed north coast of Scotland with Germany's vast arrays of solar panels, and join the power of waves crashing on to the Belgian and Danish coasts with the hydro-electric dams nestled in Norway's fjords: Europe's first electricity grid dedicated to renewable power will become a political reality this month, as nine countries formally draw up plans to link their clean energy projects around the North Sea.

The network, made up of thousands of kilometres of highly efficient undersea cables that could cost up to €30bn (£26.5bn), would solve one of the biggest criticisms faced by renewable power – that unpredictable weather means it is unreliable.
Green technology correspondent Alok Jha on the supergrid plans Link to this audio

With a renewables supergrid, electricity can be supplied across the continent from wherever the wind is blowing, the sun is shining or the waves are crashing.

Connected to Norway's many hydro-electric power stations, it could act as a giant 30GW battery for Europe's clean energy, storing electricity when demand is low and be a major step towards a continent-wide supergrid that could link into the vast potential of solar power farms in North Africa.

By autumn, the nine governments involved – Germany, France, Belgium, the Netherlands, Luxembourg, Denmark, Sweden and Ireland and the UK – hope to have a plan to begin building a high-voltage direct current network within the next decade. It will be an important step in achieving the European Union's pledge that, by 2020, 20% of its energy will come from renewable sources.

"We recognise that the North Sea has huge resources, we are exploiting those in the UK quite intensively at the moment," said the UK's energy and climate change minister, Lord Hunt. "But there are projects where it might make sense to join up with other countries, so this comes at a very good time for us."

More than 100GW of offshore wind projects are under development in Europe, around 10% of the EU's electricity demand, and equivalent to about 100 large coal-fired plants. The surge in wind power means the continent's grid needs to be adapted, according to Justin Wilkes of the European Wind Energy Association (EWEA). An EWEA study last year outlined where these cables might be built and this is likely to be a starting point for the discussions by the nine countries.

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Small-scale solar plan clashes with big energy

When it comes to renewable power, Californians tend to think big.

Big wind farms sprawl across our hills. Big solar power plants will soon blanket acres of desert. Big new power lines will bring that electricity to our cities.

This, Bill Powers insists, is exactly the wrong approach. He wants us to think small.

Powers, an engineer and energy consultant, argues that California should cover every available rooftop with photovoltaic solar panels, especially commercial buildings. The panels can be installed quickly, unlike large solar power plants that take years to win government permits. They don't require big new power lines. And their price has dropped about 40 percent in the past year.

Powers is involved in a simmering debate over renewable power development in California and the country.

Even though much of the environmental movement has rallied behind the construction of large wind farms and solar power plants, an undercurrent argues that they aren't necessary, or even desirable. Better to get energy from hundreds of smaller facilities close to home than a giant one far away.

Most industry professionals consider the idea unrealistic, but it keeps resurfacing.
Solar plants 'albatrosses'

"The solar plants in the desert are albatrosses," Powers said. "We've come to a point where (photovoltaic solar) is either going to be in the remote installations or it's going to be in the urban core. It'll be much more beneficial for those solar panels to be sitting in the urban core where they're going to be used."

It's an idea that could upend the traditional way of supplying electricity and weaken the control of utility companies. Supporters of the idea consider that a plus.

Photovoltaic solar "in the urban core is a fundamental threat to the utility business model," Powers said.

Most energy experts argue the small-scale approach won't work.

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