Breaking Down Advances in Wind Technology
Renewable energy continues to grow as wind power gets bigger and moves offshore.
The growing success of wind and solar power worldwide is a bright spot in the fight against climate change. The International Renewable Energy Agency (IRENA) says solar energy accounts for 28 percent of the world’s renewable energy generating capacity, while wind energy is right behind at 27 percent. In 2021, wind and solar accounted for 88 percent of all electricity generation capacity additions worldwide.
Wind turbine. Image used courtesy of Vestas
Recently McKinsey & Company estimated that global renewable-electricity capacity will rise by 2026 by more than 80 percent from 2020 levels—two-thirds of this growth coming from wind and solar. Further, by 2035, renewable energy will account for 60 percent of the electricity generated worldwide.
In the United States, the numbers are also moving in the right direction—wind and solar should account for 16 percent of all electric power generation in 2023, up from 14 percent in 2022.
Bigger Wind Turbines
As impressive as these numbers are, they are not enough if climate change is to be held below a 1.5°C increase by 2100. The need for ever-increasing renewable energy has led to designs for bigger, more powerful wind turbines. The Vestas V236-15,0 MW turbine, with a 15-megawatt (MW) nameplate capacity, is currently the world’s biggest and was introduced in February 2021. This giant has a rotor diameter of 714 feet and a height of 919 feet, making it also the world’s tallest wind turbine. Its 379-feet long blades are manufactured in Nakskov, Denmark.
With a 15 MW capability, the V236-15.0 will produce 80 gigawatts (GW) of electrical power per year, enough electricity to power 20,000 European households. The Vestas wind turbine has also been selected for New Jersey’s Atlantic Shores offshore wind farm and will be used in New York’s Empire Wind 1 and Empire Wind 2 projects.
Findings from a Lawrence Berkeley National Laboratory analysis predict these super-sized wind turbines will become more popular. The study indicates that future turbines are likely to be 60 percent taller than those installed in the last decade. An average height of 400 feet was typical between 2011 and 2020, which is expected to grow to more than 660 feet in the next three to five years.
Higher wind turbines can use larger rotor diameters for more power but also results in more noise generation. Bigger rotors interact, so 60 percent fewer bigger turbines can be expected to fit into the same space as in the past. The increase in individual noise created by the bigger rotors will also mean that there will need to be a greater setback from homes that neighbor the wind farms.
Offshore Wind Is Key
One way to avoid neighborhood noise complaints is to place wind farms offshore. The Biden Administration’s 30-GW-by-2030 goal pushes offshore wind development forward. In May 2022, U.S. offshore wind had a potential generating capacity of 40,083 MW. The goal beyond 2030 is to have a U.S. offshore capacity of at least 100 GW by 2050.
About two-thirds of U.S. offshore wind is located in areas with water depths of 200 feet or more. This depth makes floating offshore wind platforms more practical than those attached to the sea floor. Only about 0.1 GW of floating offshore wind has been deployed worldwide, while fixed-bottom offshore wind accounts for about 50 GW. The Biden Administration plans to reduce the cost of floating offshore wind by 70% and to deploy 15 GW by 2035.
Recyclability of Wind Turbines
The recyclability of wind turbines themselves has been the subject of some concern. While the turbine blades are made from reinforced composite materials that can be difficult to reclaim, the towers are typically made from high-strength steel, which has a not-insignificant carbon footprint. One answer proposed by Swedish Modvion is to build towers from wood. The company has built an all-wooden structure, nearly 500 feet tall, on an island outside the city of Gothenburg, Sweden. The tower will have a 2 MW turbine, but plans are in place for a 6 MW installation.
Wind turbine towers made from wood. Image used courtesy of Modvion
Modvion claims its laminated wooden structure is stronger than the steel tower it replaces and can be used with the steel components that make up the rest of the wind turbine. Because the towers are modular, they are also easier to transport than the heavy steel tower sections. The wooden components also reduce the carbon emissions that steel and concrete support structures produce.
Phasing out fossil fuels for renewable energy sources isn’t easy, but the recent improvements in wind energy technology and a willingness to set aggressive goals are providing some hope that emissions can be reduced enough to prevent cataclysmic climate change before the end of the century.