Renewables Hit The Big Time
A review of the world's biggest existing and planned renewable energy projects in the solar, wind, tidal, geothermal and wave energy sectors.
California, United States – Once upon a time, not too long ago, renewable-energy projects sized in kilowatts (kW) were considered large. The biggest solar array in 1963 had a mere 242 watts of capacity, and was installed on a lighthouse in Japan. Wind power, which took off more quickly, reached its first 100-kilowatt system in 1931, in Yalta, then part of the Soviet Union. And at that time, wave and tidal power plants were still twinkles in researchers' eyes.
At a scale that spans three continents, Desertec may well be the most ambitious renewable-energy project ever proposed. The concept seems simple enough: huge concentrating solar-thermal projects in the Sahara Desert and other sunny areas in Africa and the Middle East will supply the whole region, including Europe, Africa and the Middle East, with electricity via high-voltage direct-current transmission lines. Wind farms on the coast of Europe and Africa, as well as geothermal, photovoltaic, hydropower and biomass projects, mainly in Europe, will help balance out the grid’s power supply, but the concentrating solar-thermal projects will make up the largest piece — 100 GW, or the equivalent of 100 nuclear power stations. But putting together such a vast project, really made up of dozens (or even hundreds) of separate projects connected by the all-encompassing intercontinental transmission lines, is anything but simple. The challenges can hardly be overstated. Creating such a large grid — agreeing on electricity standards across, not only cities and provinces, but different countries and even continents — and hashing out how to share the costs and benefits of building, maintaining and managing it is a gargantuan task rife with political landmines. Issues of national energy security are involved. The logistics of building so much solar power, of getting the materials, the people and the planning in place, is nearly unfathomable. And then there’s the cost: an estimated $555 billion. The project might sound like nothing but a hazy dream, unlikely to materialize, except for the fact that a consortium of a dozen big companies, including Siemens, Munich Re, E.ON, RWE and Deutsche Bank, last year signed an agreement to try to raise the money. That’s not money in the bank, however. Aside from an expected 1 billion euros from the European Union, it will take plenty of government and private funding to make the project happen, and the donation buttons on the website make it clear the Desertec foundation is collecting wherever it can. The consortium doesn’t even plan to complete the plan to raise the money until 2012. And even with the funding, the project is expected to take decades, with the goal of completion by 2050. WIND: Dogger Bank, UK — 9 GW Moving wind-power projects offshore opens up vast amounts of space and also the potential to take advantage of steadier, faster-moving wind. The largest such project in the pipeline today is the Dogger Bank development, which is part of the United Kingdom’s third round of offshore wind licensing, according to EER. The project, with a whopping target installation capacity of 9 GW — and the potential for some 13 GW — blows away the current largest wind farm, a 782-megawatt onshore farm in Roscoe, Texas, that was completed in October 2009. Forewind, a consortium of major energy companies including Scottish and Southern Energy, RWE Innogy’s RWE npower Renewables subsidiary, Statoil and Statkraft, won the license to develop the Dogger Bank zone in January. The site is 3343 square miles large, 77 to 150 miles from shore, with depths of between 59 and 206 feet, and its unparalleled size, distance and depth create a number of logistical challenges in constructing the project and connecting it to the grid. Make no mistake, this project is years away from completion. Forewind hasn’t had set a target opening date, but has said it plans to make initial investment decisions about the project in 2014. TIDAL: Incheon, South Korea — 1.32 GW Completed in 1966, the first tidal power plant in the world, France’s 240-MW Rance plant, remains the largest today. Now South Korea is planning a project more than five times as large in the Incheon Bay. GS Engineering and Construction Corp. (GS E&C), a publicly traded company based in nearby Seoul, said in January that it plans to begin building the Incheon tidal plant in the second half of next year, if regulators approve the project. Korea Hydro & Nuclear Power Co. will run the plant, expected to cost $3.4 billion and start operations in 2017. The project involves a barrage, or an ocean dam, which traps water in a basin and uses turbines to make electricity from the water-level difference created by the tides. As countries aim to get more electricity from renewable sources, it’s possible that another project, the U.K.’s proposed Severn Barrage, could surpass the South Korean plant. The project, which could install up to 10 miles of dams and sluice gates across the Severn Estuary, has been bandied about for nearly 30 years and a timeline remains uncertain. The government is considering five different ideas for the barrage, ranging from 1.05 to 8.6 GW in capacity, as well as three alternate concepts. Tidal power interests utilities because it is reliable – the tides occur twice a day without fail — and although it is not considered constant, or baseload, power. But both the Incheon and Severn projects face significant environmental concerns and opposition. Like river dams, these tidal barrages have caused some unintended environmental and ecological consequences, making them unpopular with environmentalists. For one thing, they reduce the flow of water from the tides and the exchange of water from the basins, which impacts the water, the surrounding wetlands and the wildlife that lives in them. Other types of tidal-power technologies — including underwater turbines that operate like wind turbines, using the current itself to generate electricity without needing a barrage — could help avoid those issues, but such technologies are still under development. Three 200-MW projects are racing for the title of the largest tidal-current project. Utility SSE Renewables in March won a bid to develop two such projects in the UK’s Pentland Firth off Scotland’s northern coast: one on what’s called the Westray South site and the other, in partnership with Irish tidal-energy company OpenHydro, on the Cantick Head site. SSE’s already raised some £3.8 billion in bonds, loans and stock offering proceeds to support all its renewable projects. Meanwhile, Crest Energy has applied for approval to install up to 200 submerged turbines near the entrance of the Kaipara Harbour, on the northwestern site of New Zealand’s North Island.
At Brough Head, the companies plan to install clusters of Aquamarine’s Oyster (left) wave-power devices, which look like hinged rafts that flap as waves pass, driving hydraulic pistons that in turn spin a conventional hydro-electric turbine. The wave farm is expected to begin operations in 2013. Including this project, the partners have signed an agreement to develop up to 1 GW of such wave farms together in the U.K. and in Ireland by 2020. SSE Renewables hasn’t yet said whether its Costa Head project would also use Aquamarine’s Oysters, only saying it is working with partners and stakeholders to come up with a more specific plan for the site. Wave power has long been an attractive concept because of the large area of the global covered by oceans, the constantly moving nature of waves— which could deliver dependable baseload power, instead of the intermittent power of solar and wind — and the potentially low cost. But so far, the technologies have faced challenges, including cost and reliability issues. For one thing, sea conditions (think constantly moving saltwater) can be very rough on equipment, and maintenance and repairs more expensive than if the same equipment was easily accessible on land. Still, as governments push for more renewable energy, several companies and utilities are working on demonstration projects around the world. Freelancer Jennifer Kho has been covering green technology since 2004, when she was a reporter at Red Herring magazine. She has more than nine years of reporting experience, most recently serving as the editor of Greentech Media. Her stories have appeared in such publications as The Wall Street Journal, the Los Angeles Times, BusinessWeek.com, CNN.com, Earth2Tech, Cleantechnica, MIT's Technology Review, and TheStreet.com. http://www.renewableenergyworld.com/rea/news/article/2010/05/renewables-hit-the-big-time

