A 10% drop in wind speed can result in a 30% or more reduction in power output.
Climate change is expected to change global wind patterns, affecting wind farm productivity. Average wind speeds will decrease in some regions, potentially affecting electricity generation, while storms will become more intense and lightning strikes more frequent, posing risks to wind turbine infrastructure. Insurers and producers will need to closely monitor these trends, the Swiss Re Institute (SRI) said.
In its latest report, “Climate Change and Wind Energy: Winds of Change,” SRI said that to plan for anticipated power generation, operators must consider projected changes in wind speed and incorporate different wind forecasts into their investment plans. Risk prevention measures must address increased climate risks, such as incorporating turbines that are more resistant to wind gusts, lightning and heat.
Extremely high wind speeds also reduce productivity as turbines are shut down to prevent damage.Observations show that the frequency of tropical cyclones has decreased or remained constant globally, but the intensity of major tropical cyclones (categories 3-5) has increased.
This trend is expected to continue, with climate change expected to increase the average and maximum wind speeds during cyclones.
Additionally, tropical cyclones are forecast to move northwestward and northward, bringing more severe impacts to areas such as eastern China, Japan, and South Korea. The impacts of more intense storms will be exacerbated by rising sea levels, inland flooding, and changing wave patterns.
Investing in offshore wind is riskier and more expensive because, although the wind speeds are higher, downtime is longer and replacement costs are higher. The replacement costs for an offshore turbine can be five to ten times higher than for an onshore turbine.
Wind energy investment is inevitably riskier as easier sites are developed first, leaving riskier sites for later development.
Climate change will exacerbate these risks: Texas, for example, has great potential for wind power, but is also subject to greater exposure to storms and is projected to experience more extreme heat.
There is currently about 1 terawatt of wind power installed worldwide, equivalent to the annual electricity consumption of the Netherlands. This capacity is projected to double by 2030, still short of the net-zero target. Wind power is important in many regions; for example, the UK will get 29% of its electricity from wind in 2023, compared to an EU average of 18%.
However, climate change will impact wind power generation through changing wind patterns, increased storm intensity, more frequent lightning strikes and heat waves that can shorten equipment lifespans and increase turbine downtime.
In the second half of 2021, northwestern Europe experienced a “wind drought” with wind speeds 15% lower than average, linked to a warming Arctic and a narrowing of the temperature difference between the tropics and the poles. This phenomenon reoccurred in the winter of 2022, with low wind speeds due to a high-pressure pattern over the northeast Atlantic and Greenland.
The wind drought will have significant implications. In September 2021, wind’s contribution to the UK electricity mix fell to 2%, necessitating the restart of coal-fired power plants. In December 2022, a similar decline in wind power and rising natural gas prices pushed UK spot electricity prices to record highs.
The relationship between wind speed and power generation is nonlinear, and a 10% decrease in wind speed can result in a 30% or more decrease in output.
The Intergovernmental Panel on Climate Change (IPCC) predicts that the global average annual wind speed will decrease by 10% by 2100, although this will vary depending on the region.
One study suggests that 11% of the world’s wind farms could experience a 5% decrease in average wind speeds under low emissions scenarios (SSP1-2.6, associated with less than 2°C warming), increasing to 18% under high emissions scenarios (SSP5-8.5, associated with more than 4°C warming).
Risk transfer solutions such as index-based wind resource variability cover can help protect investors and stakeholders from financial risks due to uncertain wind speeds.
Most wind turbines are designed to withstand winds of up to 112 mph, the equivalent of a Category 3 hurricane. Speeds above this threshold can damage rotors and topple turbines.