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Floating Turbines For Offshore Wind | Earth Wise

June 18, 2020 By EarthWise Leave a Comment

Offshore wind is big in Europe. There are more than 5,000 offshore wind turbines across 12 European countries with a total capacity of more than 22 gigawatts. Almost every one of those turbines sits on a long tower sunk into the seabed and bolted into place in places where the water is 60 to 160 feet deep.

But off the coast of northern Scotland, there is the Hywind Wind Park which has five 574-foot-tall turbines located 15 miles offshore where the water is 300 feet deep. The giant masts and turbines sit on buoyant concrete-and-steel keels that allow them to stand upright and float on the water like a giant buoy. The giant cylindrical bases are held in place with mooring cables attached to anchors that sit on the seafloor.

A key advantage of floating turbines is that they can access outlying ocean waters up to half a mile deep, which is where the world’s strongest and most consistent winds blow. Another advantage is that such turbines can be installed over the horizon, out of sight of coastal residents who might not like to have wind turbines visible in their scenic ocean views.

Floating wind power has enormous potential for contributing to the expansion of renewable energy. Offshore wind is still quite a bit more expensive than land-based turbines, and the cost of electricity from distant floating turbines is more than that from near-shore wind turbines. But all of these costs are likely to come down with improving technology and increased production volume.

There are real challenges to the expanded used of floating wind farms, but the promise of harnessing so much of the open seas for electricity generation is an attractive proposition.

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Will Floating Turbines Usher in a New Wave of Offshore Wind?

Photo, posted July 17, 2017, courtesy of Crown Estate Scotland via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Recycling Coal Plants | Earth Wise

April 27, 2020 By EarthWise Leave a Comment

Over 300 coal-fired power plants in the US have stopping burning coal over the past decade. Only about 224 plants still produce power by burning coal. As a result, a new sort of recycling industry is taking shape: repurposing of coal plants.

Across the country, utilities are finding ways to redevelop these facilities. Some are industrial in nature and others a far cry from their original purpose.

In January, Beloit College in Wisconsin opened a student union and recreation center in what used to be an Alliant Energy coal-fired power plant. On the southern coast of Massachusetts, a shuttered 1,600 MW coal plant is being demolished to make way for a logistical port and support center for a planned wind farm 35 miles off shore.

In Independence, Missouri, the city is considering competing plans to recycle the Blue Valley Power plant. It may become a 50 MW battery storage facility, or possibly a biofuel plant.

Another popular reuse strategy is data centers. Data centers use tremendous amounts of power and therefore can make use of the former coal plants’ capacity to handle large amounts of electricity.

Retired coal-fired plants have built-in infrastructure and components that can be repurposed for new industry. The plants typically have access to rail, ports and waterways, as well as proximity to good highway transportation. The electrical grids to which they are connected can be reused for solar or wind farms at the site.

Given that coal plants are continuing to close, the potential to redevelop them in various ways continues to grow as well. There is a surge in interest in coal plant redevelopment because these facilities are assets of value.

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Coal-fired power plants finding new uses as data centers, clean energy hubs

Photo, posted January 10, 2017, courtesy of Rusty Clark via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Wind Power Overtakes Hydroelectric Power | Earth Wise

April 10, 2020 By EarthWise Leave a Comment

In 2019, the amount of electricity generated by wind power surpassed hydroelectric power for the first time, making wind the largest renewable source of electricity generation in the country.

Total wind generation in 2019 was 300 million MWh, which was 26 million MWh more than was produced by hydroelectric plants.

Hydroelectric generation has fluctuated between 250 and 320 million MWh over the past decade. The capacity base has been stable, so the fluctuations were a result of variable annual precipitation. Hydroelectric generation is generally greatest in the spring when rain and melting snow pack increase water runoff.

The growth in wind power is primarily a result of increasing capacity rather than any major fluctuations in wind caused by changing weather. The U.S. added about 10 GW of wind capacity in 2019, making it the second largest year for capacity additions ever, second only to 2012.

Wind energy is an intermittent source, meaning that it isn’t windy all the time. The average annual capacity factor for the U.S. wind fleet over the past decade has been 28 to 35%, meaning that is the amount of energy actually produced compared with the systems running at continuous full power all the time. By comparison, the U.S. hydroelectric fleet operated at 35 to 43% of capacity during that period. So, wind power is actually not that much less a steady source than hydroelectric power.

According to the U.S. Energy Information Administration, the government’s production tax credit, which was extended through this year, means that wind power capacity in the U.S. will continue to grow at a robust pace. Meanwhile, some dams are being decommissioned and there is little new construction in the hydropower sector.

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Wind has overtaken the top position for renewable generation in the U.S., EIA says

Photo courtesy of Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Saving Costs And Reducing Emissions From Shipping | Earth Wise

March 2, 2020 By EarthWise Leave a Comment

International shipping is a large and growing source of greenhouse gas emissions. Maritime transport produces about a billion tons of CO2 annually, accounting for about 2.5% of global greenhouse gas emissions. The environmental impact of shipping includes air pollution, water pollution, and even acoustic pollution. In many coastal areas, ships are responsible for more than 18% of some air pollutants. Overall, there are more than 100,000 transport ships at sea, of which about 6,000 are large container ships.

In recent years, the shipping sector has had both internal willingness and external pressure to reduce emissions, but shipping is a tough, competitive business and it isn’t easy to stay competitive and help protect the environment.

A recent study at Abo Akademi University in Finland has found that improved ship utilization rates and investments in environmentally sustainable technologies for enhanced energy efficiency would significantly reduce carbon dioxide emissions. Of equal importance, those same measures would contribute to lowering of freight costs.

If the same cargo volume can be shipped using less fuel, shipping companies will gain major savings in terms of fuel costs. Digitalization can provide valuable benefits. For example, new digital planning and booking systems would enable smarter use of routes while also diminishing traffic with half-empty vessels or even ones with no cargo aboard. Reducing such underutilization would improve the capacity utilization rate and eliminate emissions caused by so-called ballast traffic.

Global shipping continues to grow. It is essential that it becomes smarter and more efficient to protect the environment and improve its economics.

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Environmentally friendly shipping helps to reduce freight costs

Photo, posted February 18, 2016, courtesy of Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Storing CO2 Underground | Earth Wise

February 19, 2020 By EarthWise Leave a Comment

Capturing the carbon dioxide emitted from power plants and factories and safely storing it so it can’t enter the atmosphere has long been an attractive and desirable goal. Even though the use of renewable energy sources has been expanding rapidly, it will still be a long time before fossil fuel plants go away entirely.

The most widely considered method of carbon capture and storage is underground storage. The idea is to send the carbon dioxide through a pipeline to a place where underground rock formations can store it safely and permanently. Typically, it would be pumped deep underground – often more than half a mile down – and the site would be monitored to make sure the CO2 doesn’t leak back up to the atmosphere or into the water table.

A new study looked at how much carbon dioxide the suitable geological formations on Earth can store. The conclusion of the study is that drilling about 12,000 carbon storage wells globally could provide enough capacity to store 6 to 7 billion tons of CO2 a year by 2050. That is about 13% of global emissions.

Drilling 12,000 wells is equivalent to the amount of oil and gas drilling that has taken place just in the Gulf of Mexico over the last 70 years. The study identified locations worldwide that could handle the pressures associated with storing injected carbon dioxide.

So far, less than two dozen projects exist that capture and store carbon dioxide from fossil fuel plants. In total, these plants can capture about 36 million tons a year, which is far less than what is needed. But the new study at least shows that finding places to put captured carbon is not a problem.

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Ample Geological Capacity Exists to Store Large Quantities of Captured CO2

Photo courtesy of Equinor.

Earth Wise is a production of WAMC Northeast Public Radio.

The Potential For Offshore Wind

December 10, 2019 By EarthWise Leave a Comment

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.

Stranded Coal Assets In Japan

November 25, 2019 By EarthWise Leave a Comment

Japan is facing a looming financial problem as a result of heavy investments in coal technology that may quickly become stranded assets as renewable energy sources become increasingly inexpensive.

Japan is gradually adding more ambitious policies with regard to climate change including goals to reduce emissions and to have renewables become the main source of power over the next three decades. But despite these policy efforts, Japan is still investing heavily in coal power. Japan currently has 21 new coal projects with over 11 GW of under-construction, permitted or pre-permitted coal capacity. But these tens of billions of dollars in assets would have to be closed prematurely in order to remain consistent with the goals of the Paris Climate Agreement.

According to a new report by the Carbon Tracker Initiative, a financial think tank, and the University of Tokyo, offshore wind power will be cheaper than coal in Japan by 2022, new solar cheaper by 2023, and onshore wind less expensive by 2025. The price of offshore wind is already comparable to existing coal power in Japan. Japan had a total of 55.5 GW of solar capacity last year and has the potential to reach 150 GW by 2030.

The report notes that 42% of the global coal fleet likely became unprofitable last year and this could rise to 72% by 2040. The authors contend that building coal power today equals high-cost power and financial liabilities tomorrow. The planned and operating coal capacity in Japan is partially protected by regulations that give coal generators an unfair advantage in the marketplace. Ultimately, the stranded coal assets are likely to be passed down to consumers through higher power prices.

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Land of the Rising Sun and Offshore Wind

Photo, posted April 25, 2019, courtesy of Jen via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

New York Offshore Wind

September 18, 2019 By EarthWise Leave a Comment

New York has passed ambitious legislation to reduce the carbon emissions that cause climate change, but the state needs to start taking action to make those reductions possible. One such action it has taken is an agreement that will enable the construction of two large offshore wind projects.

The projects are to be built off the coast of Long Island. One will be 14 miles south of Jones Beach and the other 30 miles north of Montauk. The wind farms will be built by a division of Equinor, a major Danish energy company, and a joint venture between Orsted, another Danish company, and Eversource Energy, an American firm.

The two New York wind farms are expected to be operational within the next five years and have the capacity to produce 1,700 megawatts of electricity. That is about 20% of Governor Andrew Cuomo’s overall goal for offshore wind.

Wind farms are a major energy source in the United States, now providing about 7% of the country’s electricity. That compares with only 2% in 2010. But nearly all American wind turbines are on land. There is only one small offshore wind farm in the US off the coast of Rhode Island. Things are very different in Europe. For example, Britain expects to get 10% of its electricity from offshore wind next year, which is up from less than 1% in 2010.

Developers of offshore wind farms have struggled to gain a foothold in the US. Some projects have foundered because of cost issues, but others have faced opposition from politicians and coastal-property owners. But assuming the New York wind projects clear permitting and environmental hurdles, offshore wind may finally be on the move in the US.

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New York Awards Offshore Wind Contracts in Bid to Reduce Emissions

Photo, posted May 22, 2007, courtesy of Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Scottish Wind Power

September 5, 2019 By EarthWise Leave a Comment

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.

The Largest Offshore Wind Farm

July 30, 2019 By EarthWise 1 Comment

The world’s largest offshore wind farm recently began operations in the North Sea, a notoriously gusty stretch of open water that has become home to multiple large wind farms. The new Hornsea One wind farm is located 75 miles off the east coast of Yorkshire in the United Kingdom.

The first 50 turbines are now in operation and are generating electricity for up to 287,000 homes. When the farm is completed sometime next year, it will have 174 turbines with a total capacity of 1.2 gigawatts, enough to power a million homes. The farm will send electricity to the UK, Netherlands, Belgium, Germany, and Scandinavia. The Hornsea One farm will have more than twice the capacity of the current largest offshore operation, which is also in the UK.

Because the farm is so far from shore, teams of workers will live at sea for two to four weeks at a time maintaining it. Such operations are unprecedented and required new ways of operating to overcome the logistical and technical challenges of operating a massive power station far from land.

The UK has the largest offshore wind generating capacity in Europe, now more than 8.2 gigawatts and accounting for 44% of Europe’s offshore wind capacity. All that capacity is one of the big reasons that the UK has been successfully weaning itself off of coal for increasingly long periods of time.

Meanwhile, the US continues to lag far behind in offshore wind with a grand total of 0.03 gigawatts of installed capacity. That situation may be changing after the federal government auctioned off 3 major tracts of ocean late last year that potentially could generate over 4 gigawatts of power if fully developed.

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The World’s Largest Offshore Wind Farm Just Came Online

Photo credit: Hornsea Project One.

Earth Wise is a production of WAMC Northeast Public Radio.

Hybrid-Electric Aircraft

May 20, 2019 By EarthWise Leave a Comment

The commercial aviation industry is a major source of carbon dioxide emissions and, as other industries try to move towards decarbonization, its share is getting larger. But reducing emissions from aircraft is challenging because powering planes without burning fossil fuel is hard to do.

The biggest problem is that powering aircraft with electric motors instead of fossil fuel motors requires so much energy that the batteries needed to supply it become impractically heavy. While research goes on to develop lighter-weight batteries, an interim concept may pay dividends.

Just as hybrid cars represent a stepping stone towards full electrification, hybrid-electric aircraft may be a way to obtain substantial reductions in aircraft emissions. The idea is to use battery-powered electric motors to power planes, but to greatly reduce the capacity requirements of the batteries by having an on-board fossil-fuel generator to charge the batteries and supply additional needed power.

A study by the University of Illinois looked at the potential emissions reductions for hybrid-electric aircraft taking into account the emissions associated with generating the electricity that charges the batteries in the plane. The requirements in the study were that the plane needs to be able to carry the same number of passengers and travel the same distance as current aircraft.

The results were that a drivetrain that gets 50% of its power from battery charge reduced emissions by about 50% over the full lifecycle of the plane.

As batteries get lighter and the electric grid gets greener, the possibility of making major reductions in aircraft carbon emissions looks increasingly realistic. But there is a long way to go.

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Study Examines Commercial Hybrid-Electric Aircraft, Reduced Carbon Emissions

Photo, posted September 26, 2014, courtesy of Jeff Turner via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Coal Isn’t Even Cheap Anymore

May 15, 2019 By EarthWise Leave a Comment

Coal has historically been very cheap compared with many other energy sources and the reason is that it is so plentiful. The United States has especially abundant quantities of the stuff – perhaps a quarter of the world’s estimated recoverable reserves. Estimates are that at the rate at which we are currently using coal here, the remaining reserves would last about 325 years.

That would be great, of course, if the use of coal was not relentlessly destructive to the environment, hazardous to human health, and a major driver for global warming. Despite all of that, the Trump administration is a big booster of coal.

But coal has little chance of holding on to its current status, much less having some kind of renaissance. According to a new report from renewables analysis firm Energy Innovation, nearly 75% of coal-fired power plants in the United States generate electricity that is more expensive than local wind and solar resources. Wind power, in particular, can at times provide electricity at half the cost of coal.

Wind and solar power are growing by leaps and bounds. The Guardian reported that by 2025, enough wind and solar power will be generated at low enough prices in the U.S. that it could replace 86% of the entire U.S. coal fleet with lower-cost electricity.

It has been known for some time that there are places where the so-called coal crossover has already taken place. But this is actually far more widespread than previously thought. Substantial coal capacity is currently at risk in North Carolina, Florida, Georgia and Texas. By 2025, Indiana, Michigan, Ohio, and Wisconsin will join their ranks.

The biggest threat to coal is not regulators or environmentalists; it is economics.

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Renewables Cheaper Than 75 Percent of U.S. Coal Fleet, Report Finds

Photo, posted May 1, 2011, courtesy of Alan Stark via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Utility-Scale Solar On The Rise

May 8, 2019 By EarthWise Leave a Comment

According to research from Goldman Sachs, utility-scale solar power capacity is expected to grow by double digits globally over the next two years. The growth will be driven by expanding use of the technology in the United States, Europe, the Middle East, and China.

Solar power is the world’s fastest growing source of electricity generation and is slowly taking market share from fossil fuels like coal and natural gas. The transition is being driven by a combination of continuously lower prices for solar power and the impact of policies aimed at reducing emissions.

Utility-scale solar is defined as installations designed solely to feed electricity into the grid, in contrast to smaller-scale residential or commercial building units. There are now solar farms larger than half a gigawatt in generating capacity. According to the Goldman report, global utility-scale solar installations will reach 108 gigawatts in 2019, up 12% over the previous year, and will then grow another 10% to 119 gigawatts in 2020.

When residential and other smaller installations are included, most analysts expect global solar power capacity to soon hit 600 gigawatts. To put this in perspective, the global capacity only reached 100 gigawatts in 2012 and was actually less than 10 gigawatts in 2007.

Even more dramatic than the growth of solar installations is the reduction in solar cost, and the two are obviously closely related. Solar panel costs have dropped from around $70 per watt of electricity generated in 1980 to 36 cents per watt currently in the United States. When favorable policies both from governments and related to corporate sustainability targets are added to the mix, the booming growth in solar power is easy to understand.

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Large-scale solar power set for double-digit growth: Goldman Sachs

Photo, posted March 7, 2019, courtesy of Hedgerow Inc via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Bigger Is Better For Wind Energy

February 13, 2019 By EarthWise Leave a Comment

Bigger is almost always better for wind power. Bigger wind farms are better than smaller wind farms and bigger wind turbines are better than smaller ones.

The biggest turbines currently available produce nearly 10 MW of power, which is enough to supply over 2,000 homes with electricity. A wind farm with just a few of these turbines could produce enough electricity for a small town. A big wind farm, like the giant 1,550 MW Alta Wind Energy Center in California can generate enough power for a small city.

Vestas Wind Systems, an industry leader based in Denmark, has announced a 10 MW turbine that will be ready for installation in two years. The rotor diameter of the giant machine is 538 feet and the blades sweep out an area of 227,000 square feet, the size of nearly 4 football fields.

Not to be outdone, General Electric is developing a 12 MW offshore wind turbine that will stand 850 feet tall and sweep out an area of more than 400,000 square feet. GE estimates that its 12 MW turbine will achieve nearly twice the capacity factor of its 6 MW turbine.

Companies are building bigger and bigger wind turbines because they are more cost effective. The capacity factor, which is the actual energy production divided by the potential energy production, goes up as the turbines get bigger and more efficient. In terms of dollars spent to produce a given amount of power, larger windfarms are less expensive to build than smaller ones. A wind farm of 200-500 MW capacity is about 40% cheaper per MW capacity than a 25 MW wind farm.

When it comes to wind energy, there is no doubt that bigger is better.

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