The Future of Wind EnergyPosted by: | Posted on: March 31, 2017
Even today, the advantages and disadvantages of wind energy are the subject of bitter discussions. Two fundamental criticisms are often made:
For the time being, wind power is more expensive to produce than by conventional means (nuclear, thermal), it requires subsidies, mainly in the form of preferential purchase prices;
Depending on wind strength, the wind energy is “intermittent”, in a non-predictable and controllable manner, resulting in strong power variations, even stops. However, power system operators have long been taught how to manage these variations (which affect other forms of electricity production such as solar power). They consider that wind energy can cover about 20% of the electricity demand on a large network without posing any substantial technical problems.
Other solutions are also developed to overcome these power changes. In this way, wind farms are more extensive geographically, which, through their interconnection, can ensure a minimum level of energy, by playing on the “abundance” of the productions of the different zones. We also seek to develop the large-scale storage of electricity produced, notably by batteries.
Dynamic development of the wind energy sector
Despite these difficulties, wind energy is growing at a steady pace in almost every country in the world, with annual growth of 10-40%. Despite a slowdown in 2013, global growth was impressive: installed capacity reached 318 GW in 2013, an increase of 200 GW in five years1.
The European Union is well placed in view of its policy of active development of renewable energies. In 2013, it has 117 GW installed, accounting for 8% of its electricity consumption2. Progress continues despite a decline in 2013.
Offshore, the driving force behind wind energy development
The European Union’s renewable energy roadmap for 2007 estimates that wind energy could account for 13% of the electricity consumed in the EU by 2020. One third of this electricity is likely to be produced by installations Offshore (at sea, where winds are more powerful and more regular).
Europe has largely relied on off-shore, with three dominant countries: the United Kingdom, Denmark and Germany. The European Wind Energy Association (EWEA) predicts that the installed capacity of offshore wind power will grow from 6.5 GW in 2013 to 40 GW in 2020.
Different techniques are studied to improve the installation technologies. At present, the wind turbines are fixed on the seabed, which limits their zones of implantation to depths of water less than 30 meters. Systems of artificial islands or wind turbines on floating foundations anchored up to 60 meters of water depth are considered and sometimes already tested.
It also examines the possibility of using pre-existing facilities in off-shore oilfields at the end of their operation, which have high potential, to limit investments. A project is underway for the construction of 200 turbines in the Béatrice oil field, resting at a depth of 45 meters, each with 60-meter blades that can withstand the winds of the North Sea.
And the flying windmills? Researchers dream of wind turbines that would go for the winds even higher in the sky, where they are much stronger and constant. Different types are being studied or tested, but the technical problems and especially of economic profitability are considerable. The laddermills, a kind of giant kite, are made up of series of large “wings” (“kiteplanes”) threaded on a very long cable. They could harness wind power at an altitude of 9,000 meters, where the wind speed can be 20 times that at sea level. Other projects put helium-inflated balloons or wings Equipped with turbines.