A look at wind technology and performance
Wind energy technologies have developed and spread significantly over the last 20 years, and wind power's contribution to the production of electricity is constantly increasing worldwide. Electricity is currently generated almost exclusively by large onshore machines.
- By the end of 2017, more than 539 GW of wind power (onshore and offshore) had been installed in the world.
- Installed capacity grew 11% worldwide, with over 50 GW installed for the fourth consecutive year (GWEC (2018). Global Wind Report 2017).
- A record 4.3 GW of new offshore capacity was installed, increasing the cumulative capacity by 31% to 18.8 GW (GWEC (2018). Global Wind Report 2017).
- Wind power continues to be the largest non-hydropower source of renewable energy by installed capacity, with a share of 50% excluding hydropower (REN21 (2018). Renewables 2018 Global Status Report).
- In EU-28 the cumulative capacity of on-shore and off-shore wind energy reached 178.8 GW in 2018, and wind energy met 14% of EU’s electricity demand.
The cumulative installed capacity (GW) and the wind-generated electricity as a percent of electric demand in WinWind Countries is reported below (WindEurope – Wind energy in Europe in 2018. Trends and statistics):
Cumulative Capacity (GW) (onshore and offshore)
Electricity demand covered by wind (%)
Technical characteristics of current wind turbines
- The general trend is to develop ever larger and more powerful machines onshore and offshore. The current commercial wind turbines generate 2-3 MW of power, but there are already 7-8 MW machines.
- The configuration of the large onshore wind turbines is mainly a three-blade horizontal axis. The blades are connected to a hub that is in turn connected to a system for converting mechanical energy into electrical energy. These mechanisms are housed in a nacelle that is held high in the air by a support pylon (tower). The extracted power is proportional to the rotor area and the cube of the wind speed. The wind turbines can operate at fixed revolutions with direct connection to the electric grid or with variable revolutions (equipped with electronics capable of adapting the generated frequency to that of the grid) with some advantages including higher efficiency (aerodynamic optimisation in different conditions of wind), possible stress reduction and less noise at low wind speeds.
- There are two main offshore wind technologies: the first, with tower secured to the seabed, is the one used by all the current installed systems, for the most part in Northern Europe, with which it is possible to reach maximum depths of 40-50 m, and the second option is a floating installation, anchored on a platform, which is currently still in the prototype stage, but whose exploitation potential (number of suitable sites) is significant since it can reach a depth of hundreds of meters. This second option has also employed some vertical H-Darrieus systems, whose main advantage is that of positioning the electric generator at the base of the structure.
Wind key indicators
- Onshore wind is the cheapest form of new power generation in Europe today, with many countries setting records in cost reduction, deployment, and grid integration.
- From 2010-2017, onshore wind energy auction prices dropped an average of 25% and the Levelized Cost Of Electricity (LCOE)* fell by 21%.
- The Levelized Cost Of Electricity (LCOE) generated in onshore windfarms in Europe ranges from 50 to 65 €/MWh , while the LCOE generated in coal CCGT plants ranges from 73-81 €/MWh.
- Wind energy accounted for 63% of Europe’s investments in renewable energy. Onshore wind projects alone attracted 39% of the total investment activity in the renewable energy sector.
- Significant impact on employment: 260,000 people employed, with about 150,000 in Germany, and 20,000–30,000 jobs each in Denmark, France, Italy, and Spain.
- Repowering markets are starting to emerge. By 2030, 50% of the current cumulative installed capacity in Europe will have reached the end of its operational life.
- In many countries, wind is the largest contributor to emission savings from renewable energy (Denmark, Germany, Ireland, Spain, the United Kingdom and the United States).
Levelized Cost Of Electricity (LCOE) is the average revenue per unit of electricity generated that would be required to recover the costs of building and operating a generating plant during an assumed financial life and duty cycle. LCOE is used to measure the overall competiveness of different generating technologies.
Source: IEA WIND TCP- Annual Report 2017 and https://windeurope.org/policy/topics/economics/