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Continued Renewables Growth | Earth Wise

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In 2021, the world added a record amount of 295 gigawatts of renewable power.  According to the International Energy Agency, it is on pace to surpass that amount in 2022.

Almost half of the renewable buildout in the world is taking place in China.  In 2021, China accounted for 46% of worldwide renewable energy additions.  The EU and United States are the next two leaders.  The rapid buildup is especially impressive given the challenges developers have faced from the coronavirus pandemic, supply chain issues, and various construction delays.

Predictions are that the global total added this year will be about 320 gigawatts of renewables.  This amount is equivalent to the total power demands of Germany, which is the world’s fourth-largest economy.  Solar photovoltaics are forecast to account for 60% of the increase in global renewable capacity this year. 

The rapid growth in China and the EU are driven by strong pro-renewable policies.  In our country, wrangling over climate legislation and investigations into potential trade violations by Asian suppliers have held back our progress.  But over the next several years, offshore wind will begin to have a real impact on U.S. renewable installations.

According to the report by the International Energy Agency, renewable energy growth is likely to plateau in 2023 unless stronger climate policies are enacted. 

There are now more than 3 terawatts – that’s 3,000 gigawatts – of renewable generation capacity globally.  This compares with a little over 4,000 terawatts of fossil fuel generation.  Global renewable energy generation is currently projected to surpass that of fossil fuels by 2035.

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Following Record Growth in 2021, Renewables on Track for New High in 2022

Photo, posted October 17, 2016, courtesy of B Sarangi via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Plastic Recycling Isn’t Working | Earth Wise

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A recent report from several environmental organizations shows that plastic recycling rates in the U.S. have actually declined in the last several years from about 8.7% of discarded plastic to less than 6%.   Meanwhile, since 1980, per capita plastic waste generation has increased 263%, totaling 218 pounds of plastic waste per person as of 2018.

Diminishing recycling rates don’t necessarily indicate a lack of interest by the public.  Plastic recycling is a complicated process.  There are multiple types of plastic that can’t be intermingled and there are no simple and sustainable ways to recycle many forms of plastic.   On top of that, the declining recycling rate also reflects the fact that we no longer can export our plastic waste to countries like China and Turkey, which have banned U.S. waste imports.

Recycling in general is a successful practice.  Paper recycling rates are around 66% as of 2020.  Cardboard recycling was at 88.8% in 2020, and metal recycling rates range from 27% to 76%, depending on the type of metal.  Glass recycling rates are a little over 30%.  Only plastic recycling has never reached 10%, even before shipping our waste overseas and declaring it to be recycled was going on.

According to environmental organizations focused on the global plastic problem, there is no circular economy of plastics.  Perhaps if truly biodegradable plastics became practical, economical, and widely utilized, the situation would be different.  As things stand, the only solution is to reduce the production, use, and disposal of plastics.

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Plastics Recycling ‘Does Not Work,’ Environmentalists Stress as U.S. Recycling Rates Drop to 5%

Photo, posted May 13, 2021, courtesy of Ivan Radic via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Electricity From Bacteria | Earth Wise

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Microbiologists at Radboud University in the Netherlands have demonstrated in the laboratory that methane-consuming bacteria can generate electrical power.  Their study was recently published in the journal Frontiers in Microbiology.

The bacteria studied is called Candidatus Methanoperedens and in the natural environment it consumes methane in water sources that are contaminated with nitrogen including places like water-filled ditches and some lakes. The bacteria in the study make use of the nitrates in the water to break down and digest the methane. Methanogens, which are bacteria that reduce carbon dioxide to form methane, are the source of the methane in these places. 

The researchers exploited these complex interactions of bacteria to create a source of electrical power that is essentially a kind of battery with two terminals.  One of the terminals is a chemical terminal and one is a biological terminal.  They grew the bacteria on one of the electrodes where the bacteria donate electrons that result from its conversion of methane.  (Other microbiologists at the same institution had previously demonstrated electrical generation from a similar battery containing anammox bacteria that use ammonium rather than methane in their metabolic processing).

In the study, the Radboud scientists managed to convert 31% of the methane in the water into electricity but they are aiming at higher efficiencies. 

This approach represents a potential alternative to conventional biogas electricity generation.  In those installations, methane is produced by microorganisms digesting plant materials and the methane is subsequently burned to drive a turbine to generate power.  Those systems in fact have an efficiency of less than 50%.  The researchers want to determine whether microorganisms can do a better job of generating electricity from biological sources than combustion and turbines can do.

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Bacteria generate electricity from methane

Photo, posted December 3, 2008, courtesy of Martin Sutherland via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Peak Natural Gas Generation | Earth Wise

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According to a new report from the Institute for Energy Economics and Finance (the IEEFA), the U.S. most likely hit its peak usage of natural gas to generate electricity in 2020.  Growth in wind and solar power are beginning to erode the use of natural gas.

At the moment, natural gas prices are unusually high as a result of supply chain issues and the war in Ukraine.  The U.S. is shipping record amounts of gas to Europe in order to help allies to wean off of Russian gas imports.  As a result, U.S. natural gas prices are at their highest level in more than 13 years.  Heating bills in the Northeast have been exceptionally high this past winter.

These high gas prices have also thrown a temporary lifeline to coal, which has seen a recent surge.  Despite this, coal in the U.S. is continuing its long-term decline.  Several of the largest power companies – including the Tennessee Valley Authority, Duke Energy, and Georgia Power – are planning to phase out coal entirely by 2035 and shift to renewable power.

The surging prices in fossil fuels – at the gas pump and in the home – along with multiple disruptions in energy security, are supercharging the already rapid pace of growth in solar, wind, and battery energy storage projects.

Wind, solar, and hydropower currently account for about 20% of U.S. power generation.  According to the IEEFA, these renewable sources could provide more than a third of our power by 2027.  Including both renewables and nuclear power plants, the U.S. could generate more than half of its electricity from carbon-free sources by that year, which represents a massive transition from just five years ago.

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U.S. May Have Hit Peak Natural Gas Power Generation, Report Says

Photo, posted July 11, 2017, courtesy of John Ciccarelli / BLM via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

A Big Year For European Solar Power | Earth Wise

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The installed solar capacity in the European Union grew by 34% in 2021.  This means that Europe is on pace to quadruple its solar energy generation by 2030.

During 2021, the 27 countries of the European Union installed 25.9 gigawatts of new solar capacity, compared with 19.3 gigawatts in 2020.  This was the biggest year yet for solar growth, beating out the previous record of 21.4 gigawatts set in 2011.  A gigawatt of solar electricity is enough to power about 300,000 homes, so the 2021 installations can produce enough electricity for about 8 million households.  The European Union is home to about 450 million people.

SolarPower Europe, an industry trade organization, projects that solar energy capacity in the EU will increase from the current 165 gigawatts to 328 gigawatts in 2025 and as much as 672 gigawatts by 2030.

The EU has the goal of generating 45% of its electricity from renewable sources by 2030, which is an important milestone in achieving climate neutrality by 2050. 

Challenges still facing the EU include obstacles to permitting, electricity grid bottlenecks, and assurance of solar panel supplies.  Much of Europe’s supply of solar panels comes from China.  The EU wants to boost its own production of solar panels to 20 gigawatts per year by 2025.

The US currently has about 113 GW of installed solar capacity and is projected to install about 300 gigawatts of new capacity over the next 10 years.

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For the European Union, 2021 Was a Banner Year for Solar Power

Photo, posted May 3, 2007, courtesy of Bernd Sieker via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Drought And U.S. Hydropower | Earth Wise

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The ongoing severe drought in the western U.S. has led to low water levels in the rivers and reservoirs that feed hydroelectric power systems.  The Energy Information Administration is projecting a 13.9% decrease in hydroelectric generation this year compared to 2020.

Water levels in Lake Powell have fallen so low that it may not be possible to operate the power plant at Glen Canyon Dam starting as soon as 2022.  California officials took the Edward Hyatt hydroelectric plant offline in August because of low water levels on Lake Oroville.   Washington, the state with the most hydroelectric power generation, has seen an 11% drop in electricity generated to date this year as compared to last year.  That state is actually doing better than others in the West, such as California, where hydro generation is down 38%.

Hydropower accounts for over 7% of the electricity generated in the United States.  Five states – Washington, Idaho, Vermont, Oregon, and South Dakota – generate at least half of their electricity from hydroelectric dams.

The current decrease in hydropower is alarming, but it is not unprecedented.  The more significant question is whether the drop in generation this year is a sign that this power source is declining and becoming less reliable.   According to some scientists, the West is in a “megadrought” that could last for decades.

The greater concern is whether the bad years are likely to become more common because of climate change.  Climate projections agree that temperatures will continue to rise, but what will happen to precipitation levels in specific places is much less certain.  That is what will determine what the future holds for hydroelectric power.

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Inside Clean Energy: Drought is Causing U.S. Hydropower to Have a Rough Year. Is This a Sign of a Long-Term Shift?

Photo, posted May 7, 2014, courtesy of Tyler Bell via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Vineyard Wind Prepares For Construction | Earth Wise

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Vineyard Wind 1 will be the first utility-scale offshore wind energy project in the United States.  It will be located 15 miles off the coast of Massachusetts and will consist of an array of 62 wind turbines, spaced one nautical mile apart.  It will generate 800 megawatts of electricity, enough to power over 400,000 homes.

The project has recently closed on $2.3 billion of senior debt financing, which sets the stage for construction to begin.  The joint venture between Avangrid Renewables and Copenhagen Infrastructure partners is one of the single largest investments in a renewable energy project in the U.S.  The financial close is basically the final milestone for launching the project following years of clearing regulatory and other hurdles.

With the financial closing, Vineyard Wind will be instructing its contractors to begin work.  Onshore work will start this fall and offshore work will begin in 2022.

The project will use Haliade-X wind turbine generators made by GE.  These are some of the largest and most powerful wind turbines currently available, each one capable of generating 13 megawatts of electricity.  The electricity generated by the turbines will be collected by an offshore substation and then transmitted to shore.  Two submarine cables will bring the electricity from the substation to a landing point in Barnstable.  The cables will be buried six feet below the seafloor.  Underground cables will then route the power to an onshore substation in the village of Hyannis where it will be connected to the New England Grid.

Vineyard Wind is the first of many offshore wind farms in the works for the Northeastern United States.

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U.S.’s first commercial-scale offshore wind project prepares for construction

Photo, posted March 24, 2016, courtesy of Andy Dingley via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Giant Wind Turbines | Earth Wise

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Wind turbines keep getting bigger and bigger.  The reason is that the power a wind turbine can theoretically generate is proportional to the disk-shaped area swept out by its blades.  So, the bigger the blades, the more power can be produced by a single turbine.

That being said, real-world turbines don’t achieve their theoretical power output because they have limitations on efficiency.  Things like rotor blade friction and drag, gearbox losses, and generator losses limit the actual power output of a turbine. 

Despite all of these things, the latest and greatest wind turbines are absolutely enormous and produce almost unbelievable amounts of power.  Chinese manufacturer MingYang Smart Energy has recently unveiled an 866-foot tall, 16-megawatt capacity offshore wind turbine.  This narrowly exceeds both the Vestas V236 Turbine announced earlier this year and GE’s Haliade-X Turbine, rated at 15 megawatts and 14 megawatts respectively.

The rotor diameter of the giant Chinese turbine is nearly 800 feet, set by its 387-foot blades that sweep out an area of nearly 50,000 square feet.  A single one of these turbines can generate 80,000 MWh of electricity in a year, enough to power more than 20,000 households.  (It boggles the mind to consider that just one rotation of the blades of such a turbine can power a couple of homes for an entire day).

Offshore wind farms choose the largest wind turbines in part because of the high cost of installing turbines and transporting the electricity.  It is preferable to build fewer turbines because fewer towers, cables, and ground anchoring systems need to be constructed, making the project less complicated.

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This 264-meter tall offshore wind turbine is now the largest of its kind

Photo, posted November 19, 2015, courtesy of Scott Flaherty / USFWS via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Solar Power In Australia | Earth Wise

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Historically, the electricity sector in Australia has been dominated by coal-fired power stations.  Even now, coal accounts for about 60% of Australia’s electricity generation.  But since 2005, wind power and rooftop solar have led to a fast-growing share of renewable energy in total electricity generation.

Australia is the second-largest exporter of coal in the world and has proven reserves equivalent to over 1,200 times its annual consumption.  Australia is home to four of the world’s ten biggest coal mines.  But despite this abundant resource, the country is increasing its use of renewable energy.

For just a few minutes on a sunny Sunday afternoon in August, more than half of Australia’s electricity came from solar power.  Low demand and sunny skies resulted in the contribution from coal dropping to a record low of 9,315 MW while solar power provided 9,427 MW.

In 2020, 24% of Australia’s electricity came from renewable energy, up from 21% the year before.  The increase was driven by a boom in solar installation.

Australia is still a long way from meeting its commitments under the Paris Climate Change agreement.  The country ultimately needs 51 GW of new renewable energy generation by 2042 but only 3 GW of new wind and solar projects have been committed to date.

Overall, Australia has promised what has been described as the fastest energy transition in the world.  It is all very ambitious, but Australia has a lot of work to do.

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Solar power in Australia outstrips coal-fired electricity for first time

Photo, posted November 30, 2017, courtesy of D. O’Donnell / European Space Agency via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Electric Cars Are Coming Sooner Than Expected | Earth Wise

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It is widely believed that electrification is the future for vehicles.  The only question is how long the transition will take.  Predictions are all over the map, but the recent trend is to revise those predictions to say it will happen sooner than previously thought.

A recent report from the international accounting firm Ernst & Young predicts that EV sales in the US, China, and Europe will surpass those of fossil-fuel-powered vehicles five years sooner than previously expected.  The report forecasts that fossil-fueled vehicles will represent less than 1% of global sales by 2045, taking their place among other historical but essentially abandoned technologies.

Europe is expected to be the leader in EV adoption.  The forecast is that EVs will surpass legacy vehicles by 2028.  China is expected to follow by 2033.  The US is lagging behind, but even here, electrics are expected to achieve a majority of car sales by 2036.

Plug-in vehicle sales have surpassed a 10% market share in California and Tesla now has a 1.7% share of the total US car market.  Norway is the global EV leader with 3 out of 4 car buyers choosing electrics.  In that country, Tesla’s Model 3 is the top-selling vehicle of any kind.  In Switzerland, 40% of car sales are EVs or hybrids.

There are many variables that will affect the timetable for the EV transition.  Among them are the timetable for widespread use of autonomous vehicle technology, the effects of policy initiatives by governments around the world, the development of charging infrastructure, and the evolution of electricity generation and energy storage.

In any case, looking at the product roadmap for virtually every automobile manufacturer makes it clear that electric cars are the future.

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Ernst & Young: Electric Cars Are Coming Sooner Than Expected

Photo, posted April 25, 2021, courtesy of Rutger van der Maar via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Busting Electric Vehicle Myths | Earth Wise

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From the early days of hybrid vehicles right on through the current booming market for electric cars, there has been the contention by some people that these cars are responsible for comparable or even greater amounts of greenhouse gas emissions over their product lifetimes.  The arguments generally centered around the carbon costs of creating batteries for the cars as well as the emissions associated with generating the electricity used to charge them.

A new study published by the International Council for Clean Transportation reports a life cycle assessment (or LCA) that considers every source of carbon generated from the cradle to the grave of the vehicle.

Included in the assessment are the mining costs of the lithium to make batteries, the transportation of batteries across the world by container ship, the end-of-life burden, the mix of energy generation in various places around the world, and so on.

The results of the analysis are that even in India and China, which are the biggest burners of coal and oil on earth, it still results in lower emissions to drive an EV instead of an internal combustion vehicle.

Lifetime emissions of today’s average medium-size EVs are lower than comparable gasoline cars by 66-69% in Europe, 60-68% in the US, 37-45% in China, and 19-34% in India.  As electricity generation continues to further decarbonize, all these numbers will only get better.  While it is somewhat more carbon-intensive to manufacture an EV, it doesn’t take very long in the car’s life to come out ahead owning one.

Early skeptics of EVs and hybrids had more legitimate concerns a decade or so ago, but the advantages of these vehicles are now unambiguous.

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One of the Biggest Myths About EVs is Busted in New Study

Photo, posted December 30, 2020, courtesy of Chris Yarzab via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Floating Renewable Energy | Earth Wise

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A team of researchers at Texas A&M University believes that the next generation of offshore energy could come in the form of a synergistic combination of multiple renewable energy generators installed on a floating offshore platform.

Their concept for the ocean renewable energy station comprises wind, wave, ocean current, and solar energy elements that could generate electricity for anything from a coastal or island community to a research lab or military unit.  The station would be tethered to the sea bottom and could be used in locations where the water depth increases quickly, such as along the U.S. Pacific Coast or Hawaii.

Offshore wind is already commercially competitive, while wave-energy converters so far have been less cost-effective and only useful for specialized, smaller-scale applications.  The proposed ocean renewable energy station would make use of multiple different methods of electricity generation and incorporate innovative smart materials in the wave energy converters that respond to changes in wave height and frequency and allow for more consistent power production.

Denmark is already building a huge multi-source, multi-purpose ocean energy island.  This world’s first energy island will be 30 acres in area and serve as a hub for 200 giant offshore wind turbines generating 3 GW of electric power.  It is the largest construction project in Danish history, and will cost an estimate $34 billion.  As well as supplying other European countries with electricity, the goal is to use the new offshore island to produce green hydrogen from seawater, which can also be exported.  Large battery banks on the island will store surplus electricity for use in times of high demand.

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Research Underway On Floating Renewable Energy Station

Photo, posted September 27, 2014, courtesy of Eric Gross via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Solar Energy And Agriculture | Earth Wise

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According to a new study by Oregon State University researchers, co-developing land for both solar voltaic power and agriculture could provide 20% of total electricity generation in the United States with an investment of less than 1% of the annual U.S. budget.

The concept is known as agrivoltaics – using the same land for both growing crops and generating solar energy.  The proponents of agrivoltaics say that it provides more food, more energy, lower water demand, lower carbon emissions, and more prosperous rural communities.

According to the study, wide-scale installation of agrivoltaic systems could lead to an annual reduction of 330,000 tons of carbon dioxide emission in the U.S. – the equivalent of taking 75,000 cars off the road – and the creation of more than 100,000 jobs in rural communities.  All of this could be achieved with minimal effects on crop yields.

The study finds that an area about the size of Maryland would be needed for agrivoltaics to produce 20% of U.S. electricity generation.  That area of 13,000 square miles constitutes about 1% of current U.S. farmland.

The cost of the solar installations would be $1.1 trillion over 35 years and they would pay for themselves from the electricity generated within 17 years.  Installing the arrays would create the equivalent of 117,000 jobs lasting 20 years.

The researchers are going to install a fully functional solar farm on 5 acres of university owned land to demonstrate to the agricultural community and potential future funders how the study’s findings can be applied in real world agricultural systems.

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Combining solar energy and agriculture to mitigate climate change, assist rural communities

Photo, posted October 11, 2011, courtesy of Michael Coghlan via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Upstate Energy Storage | Earth Wise

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In August, the New York Power Authority announced the start of construction on one of the largest battery energy storage projects in the nation.  Located in Franklin County at the very top of New York State, the project will comprise 20 MW of lithium ion battery storage that will help the state meet its peak power needs by absorbing excess generation that can be discharged later when the grid demands it.

The Northern New York region gets more than 80% of its electricity supply from renewable sources, including the St. Lawrence hydropower project and more than 650 MW of wind generation.  Having the ability to store some of this renewable energy for later delivery will help to eliminate transmission constraints that can prevent energy from being delivered to consumers.

The battery storage facility is one of two such large systems in the state.  The other one is a 20 MW battery storage system developed by Key Capture Energy in Stillwater in Saratoga County.  That project, which was funded by NYSERDA under the state’s Bulk Storage incentive program, is connected to the wholesale transmission network and is a revenue source for Key Capture, an independent utility-scale battery storage developer based in Albany.

The new storage project’s location is an ideal opportunity to spotlight the value of energy storage given the proximity of the hydropower project and extensive wind resources.  Being able to store renewable energy will improve transmission of the state’s electric power to downstate markets as well as help meet the state’s goals for reducing its carbon footprint and increasing its reliance upon renewable energy.

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Construction begins on NYPA’s second large-scale storage project

Photo courtesy of ceedub13, CC BY 2.0.

Earth Wise is a production of WAMC Northeast Public Radio.

Generating Hydrogen From Poor-Quality Water | Earth Wise

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Hydrogen could be the basis of a complete energy system.  It could be stored and transported and could be used to power vehicles and to generate electricity in power plants.  Proponents of the so-called hydrogen economy contend that hydrogen is the best solution to the global energy challenge.  But among the challenges faced by a hydrogen economy is the development of an efficient and green method to produce hydrogen.

The primary carbon-free method of producing hydrogen is to break down water into its constituent elements – hydrogen and oxygen.  This can be done in a number of ways, notably by using electricity in a process called electrolysis.  A method that seems particularly attractive is to use sunlight as the energy source that breaks down the water molecule.

While there is an abundance of water on our planet, only some of it is suitable for people to drink and consume in other ways.    Much of the accessible water on earth is salty or polluted.  So, a technique to obtain hydrogen from water ideally should work with water that is otherwise of little use to people.

Researchers in Russia and the Czech Republic have recently developed a new material that efficiently generates hydrogen molecules by exposing water – even saltwater or polluted water – to sunlight. 

The new material is a three-layer structure composed of a thin film of gold, an ultra-thin layer of platinum, and a metal-organic framework or MOF of chromium compounds and organic molecules.  The MOF layer acts as a filter that gets rid of impurities.

Experiments have demonstrated that 100 square centimeters of the material can generate half a liter of hydrogen in an hour.  The researchers continue to improve the material and increase its efficiency over a broad range of the solar spectrum.

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New Material Can Generate Hydrogen from Salt and Polluted Water

Photo courtesy of Tomsk Polytechnic University.

Earth Wise is a production of WAMC Northeast Public Radio.

Renewables Are Slowly Taking Over | Earth Wise

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According to data released by the Federal Energy Regulatory Commission, wind, solar, and hydropower provided 100% of the 1.3 GW in new U.S. electrical generating capacity added in April 2020.  Furthermore, the FERC report revealed that renewable sources accounted for 56% of the 9 GW added during the first four months of the year.  Apart from renewables, the balance of new generation was almost entirely made up of new natural gas capacity.   There have been no new capacity additions by coal, oil, nuclear power, or geothermal energy since the beginning of the year.

Renewable energy sources now account for nearly 23% of the nation’s total available installed generating capacity and continue to increase their lead over coal, which now accounts for only 20% of the nation’s electricity generation.

FERC data also suggests that renewables’ share of generating capacity should increase significantly over the next three years.  So-called “high probability” generation capacity additions for wind, minus anticipated retirements, project a net increase of nearly 27 GW, while solar is projected to grow by 24 GW.  By comparison, net growth for natural gas is expected to be just over 20 GW. 

Hydropower, geothermal, and biomass are all expected to experience net growth while the generating capacity of coal and oil are expected to plummet.   Nuclear power is forecasted to remain essentially unchanged.

In total, over the next three years,  the mix of all renewables is predicted to add more than 50 times the net new generating capacity added by natural gas, coal, oil, and nuclear power combined.  Renewables are truly on the rise.

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Renewable Energy Provides All New US Generating Capacity in April – Forecast to Add Almost 50x More Than Coal, Oil, Gas & Nuclear Over Next Three Years

Photo, posted May 24, 2011, courtesy of Michael Mees via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Concrete Production And Diminishing Coal Burning | Earth Wise

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Coal burning is still one of the primary means of generating electricity in the United States, but its use is diminishing and doing so fairly rapidly.  The coal burning process produces residual, incombustible materials.  One of them is fly ash, which is composed of fine, glassy, rounded particles rich in silicon, aluminum, calcium, and iron oxides.  Fly ash is captured from coal plant flue gas by precipitators and bag filters. It turns out that two-thirds of this fly ash is not dumped into landfills or impoundments, but rather is put to use.

Because of its chemical and physical characteristics, fly ash can substitute for a portion of portland cement in concrete.  Using this byproduct material in making cement actually reduces its cost. Beyond cost, the addition of fly ash as a so-called supplementary cementitious material or SCM improves concrete’s long-term strength and reduces porosity and permeability.  It reduces the risk of thermal cracking and provides good long-term mechanical properties.

The amount of fly ash used in concrete products increased by 5% between 2011 and 2017 while the amount produced dropped by 36%.  Concrete production continues to increase steadily while fly ash production is steadily dropping.

Therefore, the concrete industry is looking for alternative sources of SCM.  The most obvious is the approximately 1/3 of fly ash that hasn’t been used to make concrete.  Much of that is landfilled or ponded onsite at power plants.  So, opportunities exist for excavating or dredging and recovering these materials.

As coal burning goes away, concrete manufacturing needs to make some changes.

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What Does the Changing Face of Electricity Production Mean for Concrete?

Photo, posted February 16, 2017, courtesy of Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Wind Power Overtakes Hydroelectric Power | Earth Wise

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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.

Lots Of Wind Power In Denmark | Earth Wise

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Many states and countries have established goals to generate at least half of their electricity from renewable sources by some future date, typically 2030.  A number of countries have already been able to achieve 50% or greater renewable generation for brief periods measured in days.  Australia did it this past November.  Germany has seen it on occasion as well.

Denmark has managed to complete an entire year with half of its energy coming from renewable generation.  Almost all of it – 47% of the country’s power – came from wind turbines.

Denmark has been generating much of its energy from wind power for quite a while and actually produced about 46% of its electricity from renewable sources in 2017.  Denmark was a pioneer in developing commercial wind power during the 1970s, is a major manufacturer of wind turbines, and the small country has installed over 6,000 of them.  The gains this past year mostly came from the Horns Rev 3 offshore wind farm that went online in the fall.  The 407 MW wind farm has the capacity to cover the annual electricity consumption of about 425,000 households, which is about 20% of the country.

The growth of wind power in Denmark is still ramping up.  A 600 MW wind farm in the Baltic Sea will be connected to the Danish and German electricity grid by 2021, and a wind farm of at least 800 MW capacity in the North Sea is scheduled to come online in 2025.

The Danish Parliament has passed an ambitious climate law with the goal of reducing CO2 emissions by 70% in 2030 compared with 1990.  The country’s overall goal of being carbon-neutral by 2050 does not seem like a pipe dream.

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Denmark Passes Magic 50% In Renewable Electricity Generation Milestone

Photo, posted July 12, 2009, courtesy of Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Cooling The Earth With A Warmer Arctic | Climate Change | Earth Wise

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Researchers are considering a wide range of approaches to mitigate the effects of global climate change.  Among these are various strategies of geoengineering, which must be viewed with enormous caution, given the high likelihood of unintended consequences from almost anything we might do.

Researchers at the International Institute for Applied Systems Analysis have investigated potential strategies for cooling the planet in the absence of Arctic sea ice.

The Arctic region is heating up faster than any other place on earth and its sea ice is rapidly disappearing.  Estimates are that summer sea ice in the Arctic Ocean will be largely gone within a generation.  Arctic ice and snow reflect the sun’s energy into space, which helps to keep the planet cool.  What happens if that ice is gone?

The researchers explored the fact that the Arctic Ocean ice actually insulates the Arctic atmosphere from the warmer water under the ice.  Without the ice layer, the surface water would actually increase air temperatures by 20 degrees C during the winter.  That in turn would increase the heat irradiated into space and thereby cool down the planet.

The Arctic sea ice is in part maintained because the upper regions of the Arctic Ocean have lower salinity than the Atlantic Ocean.  This stops Atlantic water from flowing above the cold Arctic waters.  So, if we were to somehow deliberately increase the salinity of the Arctic Ocean surface water, warmer, less salty Atlantic Ocean water would flow in, increase the temperature of the Arctic atmosphere, and release heat trapped in the ocean into space.

It all sounds pretty crazy, but the researchers say that given the seriousness of climate change, all options should be considered when dealing with it.

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Could we cool the Earth with an ice-free Arctic?

Photo, posted August 19, 2016, courtesy of Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

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