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Five States Stepping Up On Clean Energy | Earth Wise

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While Congress continues to face partisan gridlock on climate issues, many states have moved forward with climate action.

In 2021, five states – Illinois, Massachusetts, Oregon, North Carolina, and Rhode Island – passed laws requiring a shift to 100% carbon-free electricity or net-zero emissions.  Washington State passed a law that helps to implement its strong 2019 and 2020 climate and clean energy laws.  Washington’s new legislation establishes a carbon trading program that will help the state to meet its goals of economy-wide emission cuts and 100% carbon-free electricity.

Several other states made progress on climate and clean energy by taking targeted actions not quite as aggressive as 100% laws, but significant, nonetheless.

The five states that entered the so-called 100% club joined with the six states that had earlier passed such legislation.  Those are California, Hawaii, New Mexico, New York, Virginia, and Washington.  Both Puerto Rico and Washington D.C. are also members of the club.

The past year may well be the biggest year yet for significant clean energy legislation.  Some of the states that finally passed laws had been gearing up for it for years.  This is particularly true of Massachusetts and Illinois.

Actions by individual states are not an antidote to inaction by the federal government, but they help.  At this point, about one-third of the country’s population lives in states that have laws requiring a transition to 100% carbon-free electricity, 100% renewable electricity, or net-zero emissions. 

All of this activity began in 2015, when Hawaii passed its renewable energy law.

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Inside Clean Energy: Here Are 5 States that Took Leaps on Clean Energy Policy in 2021

Photo, posted August 12, 2021, courtesy of Glacier NPS via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Avoiding Blackouts With Renewable Energy | Earth Wise

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There are some people who worry that an electric grid heavily dependent upon intermittent sources like solar and wind power may be more susceptible to blackouts.  According to a new study by Stanford University, these fears are misplaced.

The study, published in the journal Renewable Energy, found that an energy system running on wind, water, and solar, when combined with energy storage, avoids blackouts, and lowers energy requirements and consumer costs.  In addition, implementing such a system would create millions of jobs, improve people’s health, and reduce land requirements.

The study focused on the stability in all U.S. grid regions as well as individual states based on the requirement that all electricity is provided by clean and renewable sources. No fossil fuel use, bioenergy, blue hydrogen, or even nuclear power were included in the modeling.  Critics of such a shift in the energy system point to grid blackouts during extreme weather events in California in 2020 and Texas in 2021 as evidence that renewable sources can’t be trusted.  But in both cases, renewable energy was not found to be any more vulnerable than other sources.

The study looked at the costs of the transition – which would be substantial – but found that it would pay for itself fairly quickly based on energy cost savings alone.

A significant finding of the study was that long-duration batteries were neither necessary nor helpful for grid stability.  That stability could be obtained by linking together currently available short-duration batteries.  Interconnecting larger and larger geographic regions would make the power system smoother and more reliable.  Overall, intelligent management of the electric grid can result in a reliable and clean power system.

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Stanford researchers point the way to avoiding blackouts with clean, renewable energy

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

Cheaper Electric Cars | Earth Wise

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The price of the batteries that power electric cars has fallen by about 90% since 2010.  This continuing trend will eventually make EVs less expensive than gas cars.

For many years, researchers have estimated that when battery packs reach the price of $100 per kilowatt-hour of energy storage, electric cars will cost about the same as gasoline-powered vehicles.  In 2021, the average price of lithium-ion battery packs fell to $132 per kilowatt-hour, down 6% from the previous year.  According to analysts, batteries should hit the average of $100 as soon as 2024.

It is not the case that as soon as the $100 level is reached, EVs will abruptly reach cost parity.  Across different manufacturers and vehicle types, the price shift will occur at different rates.  However, by the time batteries reach $60 a kilowatt-hour, EVs will be cheaper than equivalent gasoline models across every vehicle segment.

It is not known exactly when EVs will cost less than gasoline models, but there is little doubt that this point is coming.  We have only been talking about the purchase price of a new vehicle.  When one looks at the total cost of ownership of a vehicle, including fuel, insurance, maintenance, and depreciation, it is a different story.

Because of savings on fuel and maintenance, EVs are already in many if not most cases cheaper to own than gas-powered cars.  The Department of Energy provides an online calculator to help consumers estimate the cost differences between gasoline and electricity.

In any case, the number of electric cars on the market is increasing and the number of gas-powered cars will be shrinking.  Sooner or later, we will all drive electric.

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Inside Clean Energy: Batteries Got Cheaper in 2021. So How Close Are We to EVs That Cost Less than Gasoline Vehicles?

Photo, posted July 29, 2017, courtesy of Steve Jurvetson via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Stretchy And Washable Batteries | Earth Wise

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Wearable electronic devices are a big market but there are limitations created by the properties of the batteries that operate them.  The ideal battery for wearable electronics would be soft and comfortable, stretchable, and washable.  Researchers at the University of British Columbia have recently developed just such a battery.  The work has been described in a new paper published in Advanced Energy Materials.

The battery encompasses a number of engineering advances.  Traditional batteries are made from hard materials encased in a rigid external shell.  The UBC battery is stretchable because its key components are ground into small pieces and then embedded in a rubbery polymer.  Ultra-thin layers of these materials are then encased in the same polymer.  This construction creates an airtight, waterproof seal.

The batteries survived 39 cycles in washing machines using both home and commercial-grade appliances.  The batteries came out intact and functional.

The batteries use zinc and manganese dioxide chemistry which is safer than lithium-ion batteries in case they break while being worn.

The materials used are low-cost, so if the technology is commercialized, it will be cheap.  When it is ready for consumers, it is likely to cost no more than existing batteries.  Work is underway to increase the power output of the batteries and their cycle life.  There is already commercial interest in the technology.

There are many potential applications for such batteries.  Apart from watches and medical monitors, they might also be integrated with clothing that can actively change color or temperature.  If the batteries are commercialized, they will make wearable power comfortable, convenient, and resilient.

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Stretchy, washable battery brings wearable devices closer to reality

Photo, posted April 15, 2021, courtesy of Ivan Radic via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Carbon Capture In Denmark | Earth Wise

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Denmark has pledged to reduce greenhouse gas emissions 70% by 2030 compared with 1990 levels. The country has also banned oil exploration in Danish waters and plans to phase out offshore drilling in the North Sea by 2050.

Instead of pumping oil from the North Sea, Denmark plans to capture CO2 and store it there.  To meet its climate goals, Denmark is investing $2.4 billion in a plan to capture carbon dioxide from its energy and industrial sectors and inject it into the seabed in geological formations that previously held oil and gas deposits.

The first North Sea carbon capture and storage facilities will be put into service in 2025 and will remove nearly half a million tons of emissions from the atmosphere each year.  The carbon dioxide will be captured from energy and industrial sectors such as waste incineration and cement production.

There are multiple carbon capture projects underway around the world.  Many are directed at so-called direct air capture, which is taking carbon dioxide out of the air once it is already there.  In Iceland, a project named “Orca” is extracting CO2 from the air and piping into a processing facility where it is mixed with water and diverted into a deep underground well.  Other large direct air capture plants are being built in the U.S. Southwest and in Scotland.

Whether capturing carbon from industrial operations or directly from the air ultimately makes environmental and economic sense remains to be seen.  What is driving the development of these technologies is the troubling math that reducing emissions is not happening fast enough to stave off the destructive effects of climate change that will result from global temperatures rising too much.

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Denmark bets on North Sea carbon capture to hit climate goals

Photo, posted July 2, 2018, courtesy of Ansgar Koreng via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Solid State Batteries For Cars | Earth Wise

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Today’s electric cars run on lithium-ion batteries, the same sort that power our phones, computers, and many other consumer electronic devices.  These batteries are far superior to the batteries of the past, offering long-life, high-energy density, and recyclable components.

Lithium-ion batteries do have their drawbacks.  They may be lighter than older battery technologies, but because the electrolytes in the batteries are liquid, they are still fairly heavy.  The huge number of them in an electric car adds up to a considerable amount of weight.  In addition, the flammability of the electrolytes can lead to explosions or fires if the batteries are damaged or exposed to extreme temperatures.

Solid-state batteries are an alternative technology that contain a solid electrolyte.  Such batteries are lighter, have higher energy density, offer more range, and recharge much more quickly than lithium-ion batteries. They have been used for years in some small devices like cardiac pacemakers, RFIDs, and some wearable devices.

For all these benefits, scaling up production to the level needed to be used in cars is an expensive and challenging endeavor.  The hope is that with sufficient effort, the result will be smaller, lighter battery packs for cars that can be charged in minutes and provide extended range.

Nissan Motor Company has recently announced that it is investing $17.6 billion over the next five years towards developing solid-state batteries for cars.  No doubt other companies will also be working on the technology.

Lithium-ion batteries have proven to be quite practical for powering vehicles.  But if solid-state batteries can meet the challenges of scaled up production, the lithium-ion era might end up being a relatively brief one.

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Nissan to Spend $18 Billion Developing a Cheaper, More Powerful EV Battery

Photo, posted November 13, 2018, courtesy of FirstEnergy Corp via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Liquid Fuels From Carbon Dioxide | Earth Wise

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Most of the world’s energy demands are still being met by burning fossil fuels, thereby releasing carbon dioxide into the atmosphere.  The energy system is in the midst of a transition to renewable sources such as solar and wind power, but it will be quite some time before fossil fuels are only a minor part of energy production.  To reduce global warming, it will be necessary to prevent the carbon dioxide from fossil fuels from entering the atmosphere by capturing it and either locking it away or making use of it.

Recent research at several Chinese universities has developed a novel electrocatalyst that efficiently converts CO2 to liquid fuels containing multiple carbon atoms.  The main products of the high-efficiency reaction are ethanol, acetone, and n-butanol.  Previous electrocatalystic methods have mostly produced simpler hydrocarbons – namely, ones with only a single carbon atom.  The fuels the new catalyst produces are much more useful.

The catalyst is made from thin ribbons of a copper/titanium alloy that are etched with hydrofluoric acid to remove the titanium from the surface.  The process results in a material with a porous copper surface on an amorphous CuTi alloy.  The substance exhibits remarkably high activity, selectivity, and stability for catalyzing the reactions leading to the production of the hydrocarbon fuels.

Converting carbon dioxide into liquid fuels would be advantageous because they have high energy density and are safe to store and transport.  Apart from preventing carbon dioxide from entering the atmosphere, the process could also be a way to make use of excess energy produced by solar and wind generation by essentially storing that energy in the form of liquid fuels.

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Liquid Fuels from Carbon Dioxide

Photo courtesy of Angewandte Chemie via Wiley-VCH.

Earth Wise is a production of WAMC Northeast Public Radio.

Solar Canopies | Earth Wise

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There are plenty of solar panels on residential rooftops but there are also increasing numbers of arrays of them on croplands, arid lands, and grasslands. Large solar arrays are mostly built in open spaces like these rather than in developed areas.  The reason is that it is cheaper to build on undeveloped land than on rooftops or construct covered parking lots.

However, building on undeveloped land is not necessarily the smartest idea.   Undeveloped land is a dwindling resource that is needed for many different things:  growing food, sheltering wildlife, storing and purifying water, preventing erosion, and sequestering carbon. 

Putting solar panels on parking lots has the appeal that they are abundant, close to electricity customers, and are on land that already has been stripped of much of its biological value.

Putting a solar canopy over a parking lot can produce large amounts of electricity and has the added benefit that it would provide shade for cars.  For example, a typical Walmart supercenter might have a five-acre parking lot, which is enough to support a 3-megawatt solar array.  If Walmart put solar canopies on all of its 3,500+ super centers, it would provide 11 gigawatts of solar power – as much as a dozen large coal-fired power plants.

Solar canopies are still pretty uncommon, but some examples are ones at four DC Metro rail stations, one at JFK Airport, and a large one at the Rutgers University Piscataway campus.

Building parking lot solar canopies is much more expensive than putting solar arrays on open space, but they do eventually pay for themselves. Despite active opposition by utility and fossil fuel interests, solar canopies may eventually be a common sight.

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Why Putting Solar Canopies on Parking Lots Is a Smart Green Move

Photo, posted January 10, 2020, courtesy of Tony Webster via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Batteries On Wheels | Earth Wise

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Transportation accounts for nearly a quarter of the direct carbon dioxide emissions coming from burning fuel.  As a result, electrification of transport is one of the major ways we can reduce emissions.  Increasing the number of electric vehicles over time is essential for meeting emissions targets.

But electric vehicles have the potential to do more than deliver emissions reduction; they can also provide other energy services.

More and more electric cars provide over 200 miles of driving range, but most cars are actually driven no more than 30 miles a day.  As a result, the fleet of electric cars represents a huge bank of energy stored in battery packs and mostly sitting around unused.  This presents an opportunity to leverage this resource.

Car battery packs could be used to absorb excess renewable energy generated in the middle of the day (for example from solar installations) or at night (from wind farms) and potentially then to export stored energy to power homes and support the grid.  This energy system is known as V2G, or vehicle-to-grid technology.

The University of Queensland in Australia has launched a unique international trial to see if the spare battery capacity in vehicles could be used for these purposes.  The university has partnered with Teslascope, which is an online analytics platform used by Tesla owners to track the performance of their cars.  Tesla owners wishing to be part of the study authorize the collection of their data and, in turn, receive a free 12-month subscription to the Teslascope service.  The study will collect data from Tesla owners in Australia, the US, Canada, Norway, Sweden, Germany, and the UK.

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Can EV spare battery capacity support the grid?

Photo, posted February 8, 2009, courtesy of City of St Pete via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Efficiency Of Offshore Wind | Earth Wise

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After many years of debates, delays, and controversies, offshore wind is about to expand in a big way in the United States.  The White House has announced the goal to deploy 30 gigawatts of offshore wind – enough to power 90 million homes – along the East Coast seaboard by 2030.

In New York State, there are now five offshore wind projects in active development.  The state goal is to have nearly a gigawatt of offshore wind by 2035, enough to power over 4 million homes.

These projects involve the use of thousands of physically large, high-capacity wind turbines deployed over large areas at an unprecedented scale.  Such mammoth installations bring with them unique problems.

Low-turbulence conditions over water lead to the fact that individual wind farms will experience each other’s wake (the disturbance of their airflow) even when turbine arrays are 15 to 50 miles apart.  As a result, turbines may fatigue earlier, and groups of turbines may experience up to 30% lower power production due to wake effects.

Industry trends are causing an increased probability of large wake-induced energy losses within individual wind farms and an increasing probability of wake interactions.

These issues have been studied in new research published by researchers at Cornell University.  The research presents simulations that may be helpful to optimize turbine spacing in the ongoing deployments and assist plans for future ones.  Improved understanding of wind turbine and wind-farm wake is essential in ensuring that the financial investments in offshore wind result in electricity-generation goals met at the lowest possible cost.

According to Department of Energy studies, offshore wind resources around the United States could potentially generate more electricity than the entire country currently uses.

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Scientists bring efficiency to expanding offshore wind energy

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

Earth Wise is a production of WAMC Northeast Public Radio.

A Smart Heat-Blocking Window | Earth Wise

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An international research team led by Nanyang Technological University in Singapore has invented a ‘smart’ window material that controls the transmission of heat without blocking the view through the window.  The technology could help reduce the amount of energy needed to cool and heat buildings.

The new material can be the basis of an electrochromic window that can block or pass infrared radiation at the flick of a switch.  Current electrochromic windows can be darkened when switched on and are found in many ‘green’ buildings as well as in many car mirrors.  But these windows are only effective in blocking visible light so infrared radiation – meaning heat – still passes through them.

The new coating material blocks up to 70% of infrared radiation when switched on but still allows up to 90% of visible light to pass through.  The material is a specifically designed composite nanostructure and utilizes advanced materials including titanium dioxide, tungsten trioxide, neodymium, niobium, and tin oxide.  It is intended to be coated onto glass window panels and be activated by electricity when needed.  The material was put through rigorous on-off cycles to assess its stability and durability and it appears to offer superior performance in that regard compared with current electrochromic technology.

The researchers also created a switchable system that helps control conducted heat, which is the heat from the external environment.

The combination of the two technologies could result in smart windows that control two types of heat transmission:  infrared radiation and conduction heat.  Such technology could help conserve energy used for the heating and cooling of buildings and could contribute to the future design of sustainable green buildings.

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Scientists invent ‘smart’ window material that blocks rays without blocking views

Photo, posted March 11, 2016, courtesy of Open Grid Scheduler via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Reducing Emissions From Cement Manufacturing | Earth Wise

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Cement is the basic ingredient of concrete, which is the most widely used construction material in the world.  About 8% of global carbon dioxide emissions are associated with cement production.

More than half of these emissions come from making clinker, which is a major component of cement produced by heating ground limestone and clay to a temperature of over 2500 degrees Fahrenheit.  Some of the emissions come from burning fossil fuels to heat the materials, but much of them come from the chemical reaction that creates the clinker.

The Portland Cement Association, which represents 92% of US cement manufacturing capacity, has recently released its “Roadmap to Carbon Neutrality”, which lays out a plan to reach carbon net zero across the cement and concrete value chain by 2050.

The plan includes the greater use of alternative fuels to reduce emissions from energy use.  It also involves the adoption of newer versions of cement such as Portland limestone cement, which reduces CO2 levels.  The industry has already reduced emissions by some shifting to Portland limestone cement, but it still only represents a small fraction of cement production.

The most significant strategy would be the adoption of carbon capture, utilization, and storage (or CCUS) technologies.  The idea is to capture the CO2 generated in the production of clinker and inject it into the fresh concrete.  It would actually be permanently sequestered in the concrete and would not be released even if a structure is demolished in the future.

It will take a combination of technologies and initiatives for the cement industry to reduce its emissions.  Fortunately, the industry appears to be committed to that goal.

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US cement manufacturers release their road map to carbon neutrality by 2050

Photo, posted March 26, 2014, courtesy of Michael Coghlan via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

SuperHot Rock Geothermal Energy | Earth Wise

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The United States in a world leader in geothermal energy.  There are geothermal power plants in 7 states which produce about half a percent of the country’s electricity.  Conventional geothermal energy plants take advantage of natural underground sources of heat such as geysers, superheated underground reservoirs, and such.  Steam from these sources activates generators that produce electricity.  However, there are not many places where these systems can be built.

More recently, there has been growing interest in so-called enhanced geothermal systems (or EGS systems) which generate geothermal electricity without the need for natural convective hydrothermal sources.  There are many places where underground heat is available but no existing water taps into it.  The idea is to tap into the earth’s deep geothermal resources by fracturing rock and pumping water into it to be heated. 

AltaRock Energy, a Seattle-based company that develops EGS technology, has recently announced the results of a comprehensive technical and economic feasibility study demonstrating the potential benefits of an EGS system that could use high-temperature impermeable rock deep below the Newberry Volcano near Bend, Oregon.  The so-called SuperHot rock there is in excess of 750 degrees Fahrenheit.

Based on measurements at the site and modeling, the study determined that an EGS system at the site could cut the levelized cost of electricity in half when compared with a conventional EGS resources at 400-500 degrees. 

The company expects that the study will pave the way for the development of the first SuperHot Rock geothermal resource in the United States.

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AltaRock clears hurdle in quest for ‘next generation’ geothermal resource

Photo, posted June 26, 2018, courtesy of David Fulmer via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Large Solar Projects In The U.S. | Earth Wise

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The United States now has over 108 gigawatts of total solar generating capacity, which is enough to power about 19 million homes.  There are more than 3 million solar installations across the country, the majority of which are residential systems.

The growth in solar power has been enormous over the past 13 years.  In 2008, the total solar capacity in the U.S. was 0.34 gigawatts.

In recent times, utility-scale solar installations have been on the rise.  At least 10 systems in excess of 100 megawatts have come online just in 2021.  These systems have been built in Georgia, Ohio, California, Texas, and Nevada.  Other large installations have come online in Virginia, Utah, Indiana, and Florida.  Overall, Texas has had the most new installations, followed by California and Florida.

The largest utility-scale solar project completed this year is the Eunice Solar Project in Andrew, Texas.  The 420-megawatt project is part of the Permian Energy Center which also features 40 megawatts of battery energy storage.

The pipeline for new utility-scale solar projects under construction includes more than 17 gigawatts, so there is strong continuing growth in the industry.

The Biden administration has proposed a blueprint for the nation to produce 45% of its electricity from solar power by 2050.  Currently, solar energy contributes about 4% of the country’s power.  Being able to produce almost half the country’s electricity from the sun by 2050 would require a vast transformation in technology and the energy industry.  Whether there is the political will and the wherewithal to achieve this remains to be seen.

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U.S. Solar Market Insight

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

Decarbonizing The Most Polluting Heavy Industries | Earth Wise

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The production of steel, cement, and ammonia accounts for about 20% of the carbon dioxide humans pour into the atmosphere.  Modern cities are largely constructed from concrete and steel and most of our food is grown using fertilizer made from ammonia. 

The most widely discussed solutions to decarbonizing these industries are green hydrogen and carbon capture and storage or CCS.

Steel manufacture is responsible for 11% of society’s emissions.  Most production starts by burning coal in a blast furnace. Using CCS could reduce emissions from burning the coal.  But the blast furnace could be eliminated entirely by the use of electrolysis to produce the pure iron needed to make steel.  This would be extremely energy-intensive but using a low-carbon source like green hydrogen could greatly reduce the emissions from making steel.

Ammonia is made by producing hydrogen from natural gas and then combining it with atmospheric nitrogen.  Both the hydrogen production and ammonia synthesis are energy intensive.  Using green hydrogen would eliminate emissions from the hydrogen production itself and new research on catalysts aims at lower-temperature, less-energy intensive ammonia synthesis.

Decarbonizing cement manufacturing is perhaps the toughest challenge.  Cement is made in a high-temperature kiln, typically heated by burning fossil fuels.  The process converts calcium carbonate and clay into a hard solid called clinker.  The main byproduct of that is even more carbon dioxide.  Burning green hydrogen and capturing carbon emission are about the best hope for reducing cement manufacturing emissions.

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Can the World’s Most Polluting Heavy Industries Decarbonize?

Photo, posted June 30, 2009, courtesy of Portland Bolt via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Greenhouse Gas Removal And Net Zero | Earth Wise

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Reducing the amount of greenhouse gas emissions can slow the progress of global warming but only reaching and sustaining net zero global emissions can halt the progress of climate change.

The move to renewable power and the use of electric transport are substantial and essential ways to reduce emissions.  But even if these transitions take place on a rapid timescale, they will not eliminate all emissions.  Many industrial activities and, especially, agriculture will continue to contribute substantial greenhouse gas emissions.   There are efforts to reduce the contributions of these things, but there are no zero-emission substitutes for most of them.

As a result, actually removing CO2 from the atmosphere once it is there is essential to achieve net zero emissions.  If greenhouse gas removal can be scaled up sufficiently, it opens the option of going “net negative”, which would be the ideal way to mitigate and, better still, reverse the effects of climate change.

There are multiple approaches to carbon dioxide removal.  Some are natural, involving ways of capturing and storing carbon in trees, biochar, and peatlands.  Others are technological.  An example is the system that has just gone into operation in Iceland that uses fans, chemicals, and heat to capture CO2 and then mineralize it in volcanic rock.   Another is a system being tested in the UK that captures CO2 from growing biomass and pipes it to storage under the North Sea.

Much of the attention on carbon capture technology is aimed at trapping the emissions from fossil fuel power plants, but the need to remove carbon dioxide that has entered the atmosphere in other ways is ultimately far greater.

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CO2 removal is essential to achieving net zero

Photo, posted August 17, 2013, courtesy of Joshua Mayer via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

A Solar-Powered Steel Mill | Earth Wise

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The steel industry is an essential part of modern society.  Economically, the U.S. steel industry produces goods valued at more than $100 billion a year and employs more than 80,000 people.  The steel industry is also a major contributor to greenhouse gas emissions.   On average, 1.85 tons of CO2 are emitted for every ton of steel produced.  Overall, the steel industry generates between 7 and 9% of the direct emissions that come from the global use of fossil fuel.

The industry is determined to reduce its environmental impact.  Steel is 100% recyclable and indeed much of it is recycled.  Over 2 billion tons of steel were produced in 2019. Meanwhile, more than 700 million tons of steel scrap are recycled each year.  Recycling greatly reduces the energy impact of the steel industry.

The industry has also significantly reduced its energy usage over the years using sophisticated energy management systems and energy recovery efforts.  Since 1960, the amount of energy needed to produce a ton of steel has dropped by 60%.  But making steel is still very energy intensive.

Recently, Lightsource bp announced that its 300 megawatt Bighorn Solar project in Colorado will be used to allow EVRAZ’s Pueblo steel mill to be the world’s first steel mill to run almost entirely on solar power.

The solar project, which will be fully online this month, is the largest on-site solar facility in the U.S. dedicated to a single customer.  (The Bighorn Solar project features 750,000 solar panels located on 1,800 acres).

The project demonstrates that even challenging industrial sectors can be decarbonized when companies work together on innovative solutions.

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Colorado steel mill becomes ‘world’s first’ to be run almost entirely on solar

Photo, posted October 16, 2017, courtesy of UC Davis College of Engineering via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Iron Flow Batteries | Earth Wise

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Lithium-ion batteries power computers, cell phones, and increasingly, automobiles.  They started out being rather expensive but have become dramatically cheaper over the last decade, with prices dropping about 90%.  Batteries are needed to store clean power from wind and solar generation and lithium-ion batteries are increasingly being used for that purpose as well.

Utility-scale energy storage requires substantial battery installations and battery cost is still very much an inhibiting factor in the widespread adoption of the technology.  Lithium-ion battery costs continue to drop but because they require expensive materials like lithium and cobalt, there are limits to how low their prices are likely to get.

As a result, researchers have continued to seek ways to produce batteries made out of cheaper materials.  Among the more promising technologies are flow batteries, which are rechargeable batteries in which electrolyte flows through electrochemical cells from tanks. 

Flow batteries are much larger than lithium-ion batteries and include physical pumps to move electrolytes.  They typically are sold inside shipping containers.  Clearly, such batteries are not suitable for use in vehicles, much less in consumer electronics.  Nevertheless, they represent a practical option for grid storage.

A company called ESS has developed an iron flow battery suitable for utility energy storage.  Clean energy firm CSB Energy plans to install iron flow batteries at several solar projects across the U.S. that will store enough energy to provide power 50,000 homes for a day.  According to ESS, the iron-based batteries should sell for about half the price of lithium-ion batteries by 2025 and be able to store energy for longer periods.

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New Iron-Based Batteries Offer an Alternative to Lithium

Photo, posted March 21, 2021, courtesy of Nenad Stojkovic via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

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