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Global Stilling | Earth Wise

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During the summer of 2021, much of Europe experienced a “wind drought” – wind speeds in many places were about 15% below average.  In the UK in particular, winds were unusually calm and wind energy production was dramatically reduced.

Globally, wind speeds have been dropping by about 2.3% per decade since the 1970s.  In 2019, however, global average windspeeds actually increased by about 6%.  The question is whether a trend of slowing winds – so-called global stilling – is associated with climate change or is just natural variability in action.

Wind results from uneven temperatures in air masses.   Much of the world’s wind comes from the difference between the cold air at the poles and the warm air at the tropics.  Because the Arctic is warming much faster than the tropics, it is possible that winds will continue to decline around the world. 

Another factor people cite is the increase in surface roughness.  The number and size of urban buildings continues to increase, which acts as a drag on winds.

Some models predict that wind speeds will decrease over much of the western U.S. and East Coast, but the central U.S. will see an increase.  Experts do not all agree about what is happening with global winds.  Many believe that the observed changes to date have been within the range of variability.  Furthermore, some places have been windier than usual.

All of this really matters for many reasons.  Europe is increasingly dependent upon wind power as an alternative to fossil fuels.  A 10% drop in wind speed results in a 30% drop in energy generation.   Whatever their cause may be, wind droughts cannot be ignored.

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Global ‘Stilling’: Is Climate Change Slowing Down the Wind?

Photo, posted June 28, 2008, courtesy of Patrick Finnegan via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

The Potential For Offshore Wind

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According to a new report from the International Energy Agency, offshore wind technology has vast potential for meeting our energy needs.  In total, offshore wind has the potential to generate more than 420,000 terawatt-hours of electricity each year, which is more than 18 times the global electricity demand that exists today.

Based on current policy targets and plummeting technology costs, offshore wind could increase 15-fold by 2040, becoming a $1 trillion industry and eliminating 5 to 7 billion tons of carbon dioxide emissions annually.

Offshore wind today generates just 0.3% of the world’s electricity, but its’ use is growing rapidly.  The industry has grown nearly 30% a year since 2010, and 150 new offshore projects are currently in development around the world.  The leading countries are in Europe – especially in the UK, Germany, and Denmark – but China is greatly expanding its offshore capacity and the US, India, Korea, Japan, and Canada are also expected to make large investments in offshore wind going forward.

Offshore wind is in a category of its own because it is considered a variable baseload power generation technology.  This is because the hourly variability of offshore wind is much lower than solar power or onshore wind.  Offshore wind typically fluctuates far less from hour-to-hour than the other variable energy sources.

Technology improvements and industry growth are driving steep cost reductions for offshore wind.  The cost of offshore wind is expected to be cut in half in the next five years, dropping to $60 per megawatt-hour, which is on par with solar and onshore wind and cheaper than new natural gas-fired capacity in Europe.

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Offshore Wind Has the Potential to Fulfill Global Electricity Demand 18 Times Over

Photo, posted August 9, 2016, courtesy of Lars Plougmann via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Europe Is Warming Faster Than Predicted

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A new study has found that Europe is warming faster than even climate models projected.  The number of summer days with extreme heat in Europe has tripled since the 1950s, while the number of days with extreme cold has decreased by factors of two or three depending on the region.

According to climate scientists at the Swiss Federal Institute of Technology in Zurich, the climate trends are much larger than what would come from natural variability and are a clear signal of climate change.  Extremely hot days in Europe have become hotter by an average of more than 4 degrees Fahrenheit while extremely cold days have warmed by more than 5 degrees.  The research examined data from weather stations across Europe from 1950 to 2018.  Over 90% of the stations recorded increasing temperatures over time, a percentage much too high to be purely from natural climate variability.  The results also showed that the region was warming even faster than climate models projected.

The research results come after an extremely hot summer in Europe.  Southern France hit 114.8 degrees, a new record, in June.  Germany, the Netherlands, and Belgium all recorded all-time national temperature highs.  The National Oceanic and Atmospheric Administration recently announced that July was the hottest month ever recorded.

European summers and winters will only grow hotter in the coming years as climate change accelerates.  The rapidly increasing temperatures will impact cities and people that are unprepared for them and pose real risks for residents in the coming decades.  Extreme heat is dangerous because it stresses the human body, potentially leading to heat exhaustion or heat stroke.

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Europe warming faster than expected due to climate change

Photo, posted July 30, 2011, courtesy of Marcel de Jong via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Scottish Wind Power

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Scotland is a windy country.  Most wind turbines in the European Union produce electricity at an average of 25% of their maximum rated power as a result of the variability of wind resources.  The west and northern coasts of Scotland have an average capacity of 31% or more.  Some wind farms in Scotland have achieved more than 50% capacity over the course of a year.

As of the end of last year, Scotland had more than 8 GW of installed wind power capacity.  This included 7.8 GW of onshore wind and 623 MW of offshore wind generators.  Estimates are that more than 11 GW of onshore wind could be installed in Scotland.  The total offshore potential is far greater than that but would be much more expensive.  There are multiple large-scale wind farms proposed or under construction in Scotland.

All of this growth in wind power has led to some remarkable results.  During the first half of 2019, wind turbines in Scotland produced enough electricity to power every home in the country twice over.  Scottish wind farms generated nearly 10 million megawatt-hours between January and June, which is equal to the consumption of 4.5 million homes during that period.   That is enough to take care of all of Scotland’s homes plus a large portion of northern England’s. 

Scotland has set a target of generating half of its electricity from renewable sources by 2030 and decarbonizing its energy system almost entirely by 2050.  The recent performance of its wind power installations shows that the country might be able to reach its goal much sooner than anticipated.

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Scotland’s Wind Farms Generate Enough Electricity to Power Nearly 4.5 Million Homes

Photo, posted March 27, 2017, courtesy of Ian Dick via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Economics Of Solar And Wind Power

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It is well-known that the cost of both solar and wind energy has been dropping dramatically in recent years.  That trend is largely responsible for the rapid growth of both power sources.   A recent study has revealed just how remarkable the economic progress has been.

[Read more…] about Economics Of Solar And Wind Power

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