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Powering Britain with sun and wind

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The United Kingdom is quite small in size compared with the US, but its population of 67 million makes it a fairly large country with substantial energy needs.  A recent study by Oxford University looked at the ability of wind and solar power to provide for those energy needs over the course of time.

According to the study, Britain’s energy needs could easily be met entirely by the two sources of clean power.  Wind and solar can provide significantly more energy than the highest energy demand forecasted for 2050 and nearly 10 times the current electricity demand. 

Britain currently requires 299 TWh per year.  The Oxford study found that wind and solar could generate as much as 2,896 TWh per year. Furthermore, the researchers stated that these estimates are intentionally conservative, taking into account concerns around land use and the visual impact of installations.

The analysis assumes that offshore wind would produce nearly three-quarters of the energy required.  Onshore wind would contribute about 7%, while taking up only 0.07% of the country’s land.  Utility-scale solar would add about 19% of the power.  The small remainder comes from rooftop solar.  The researchers do point out that the power grid would require significant upgrades to handle all this renewable energy and that there would need to be appropriate quantities of energy storage. 

According to the authors of the study, achieving these results is a question of ambition rather than technical feasibility.  So far, the UK government has not been aggressive in making the transition to renewable energy.

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Wind and solar power could significantly exceed Britain’s energy needs

Photo, posted November 4, 2021, courtesy of Steve Knight via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Geologic Hydrogen | Earth Wise

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There is great interest in the potential use of hydrogen as a fuel or an energy storage medium.  Unlike hydrocarbon-based fuels, pure hydrogen combustion produces nothing but water as an emission.  But most hydrogen used at present is made by reforming natural gas, which is a process that results in carbon dioxide emissions.  Thus, the search goes on for cost-effective and energy-efficient ways to make “green hydrogen” that doesn’t result in greenhouse gas emissions.

Researchers at Colorado University Boulder are investigating the potential effectiveness of coaxing hydrogen from subterranean rocks – a commodity known as geologic hydrogen.

When water mixes with iron-rich minerals deep in the earth’s crust, ensuing chemical reactions can generate pockets of hydrogen gas. 

The questions are whether it is possible to bring these deposits up to the surface without harming the environment or human communities in the process and whether they can be extracted in large enough quantities to meet growing global energy demands.

The Colorado researchers will conduct experiments both in the lab and hundreds of meters below the earth’s surface to see if it is possible to induce the subterranean rock to make more hydrogen than it normally does.  If the hydrogen-producing reactions can be accelerated, then geologic hydrogen could become a clean and abundant energy source.

Geologists have known about hidden underground deposits of hydrogen for a long time, but recent research has found that there may be a lot more of it than once thought.  According to a 2022 report by the US Geological Survey, there may be enough hydrogen below ground to supply humanity’s need for fuel for hundreds of years.

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Can rocks produce abundant clean energy? New project to explore

Photo, posted December 26, 2013, courtesy of Juozas Šalna via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Storing Energy In Abandoned Mines | Earth Wise

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An international study led by researchers from Austria has developed a novel way to store energy by transporting sand into abandoned underground mines.  The technique is called Underground Gravity Energy Storage or UGES.

As the world deploys growing amounts of wind and solar energy, it is increasingly important to find ways to accessibly and efficiently store that energy to eliminate the inherent variability of the generation.  There are many ways to store energy on a short-term basis – most commonly in batteries – but cost-effective long-term storage is still in its early stages.

The UGES technique generates electricity by lowering sand into an underground mine thereby converting the potential energy of the sand into electricity by the same regenerative braking effect used in hybrid and electric cars.  The lowering sand operates a generator.   Storing energy is accomplished by lifting the sand from the mine with electric motors to an upper reservoir where it is ready for the next cycle.  By its nature, this storage technique has an indefinite duration, unlike batteries, for example, which lose energy to self-discharge.

The main components of UGES are the mineshaft, motor/generator, sand storage sites, and mining equipment.  The deeper and broader the mineshaft, the more power can be extracted from the plant, and the larger the mine, the more energy can be stored. Mines generally already have the basic infrastructure needed and are connected to the power grid.  The researchers estimate that there is global potential of 7 to 70 TWh of storage. Total global generating capacity is currently at the lower end of that range.

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Turning abandoned mines into batteries

Photo, posted October 21, 2020, courtesy of Christine Warner-Morin via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

A Big Year For Rooftop Solar | Earth Wise

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The global capacity of rooftop solar power grew by 49% in 2022.  Overall, the installed amount of rooftop solar grew from 79 gigawatts to 118 gigawatts last year and it is projected to reach 159 gigawatts by the end of this year.  By comparison, a typical nuclear power plant can produce 1 gigawatt; a gas-powered power plant is typically half a gigawatt.

Rooftop solar constitutes a relatively small fraction of the total global installed solar capacity, which is dominated by utility-scale solar arrays.  Total installed solar capacity rose from 950 gigawatts to 1,177 gigawatts last year and is projected to reach 1,518 gigawatts this year.  That is enough power to meet more than half the electricity demand of the European Union.

The rapid growth of solar power can only continue if there is more energy storage put in place to manage the peaks and troughs in solar output.  Countries will also need to upgrade their power grids to be able to transport excess solar power from where it is generated to where it is needed.   Bottlenecks in the grids of most of the leading solar-producing nations are already interfering with further solar development.

The overall potential for rooftop solar is based on the number of rooftops that would be suitable for solar power, which depends on the size, shading, orientation, and location of the roofs.  According to the National Renewable Energy Laboratory, rooftops in the United States have the potential for more than 1,000 gigawatts of solar capacity. Currently, only about 4% of US homes have rooftop solar. 

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Rooftop Solar Grew Nearly 50 Percent Globally Last Year

Photo, posted November 16, 2022, courtesy of Oliver Knight via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Geothermal Energy Storage | Earth Wise

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About 12% of the energy consumed by humanity is used to heat and cool homes and businesses.  A study by researchers at Lawrence Berkeley National Laboratory and Princeton University looked at a novel approach to making use of underground water to maintain comfortable temperatures and reduce consumption of natural gas and electricity.

The idea is to use aquifer thermal energy storage (known as ATES) to provide both heat in the winter and cooling in the summer.  The concept leverages the heat-absorbing property of water and natural geological features.  The idea is to pump up water from existing underground reservoirs and heat it at the surface using environmental heat or even excess energy from solar or wind generation.  Then the warm water is pumped back down. It stays warm for a long time – even months – because the earth is a good insulator.  When the water is pumped back up in the winter, it is much hotter than the ambient air and can be used to supply heat to buildings.

Alternately, water can be pumped up and cooled in the winter and then put back down underground and stored until cooling is needed in the summer months.

This technology has not been used much in the US, but it is gaining recognition internationally, particularly in the Netherlands.  It can perform very well in areas with large seasonal fluctuations.

The research study used modeling and various simulations to estimate how much energy ATES could save on the US grid.  The results showed that adding ATES to the grid could reduce consumption of petroleum products for heating and  cooling by up to 40%.  The system could also help prevent blackouts by reducing high power demand during extreme weather events.

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Underground Water Could be the Solution to Green Heating and Cooling

Photo, posted February 19, 2012, courtesy of Sanjay via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Minimizing The Impact Of EVs On The Grid | Earth Wise

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Two current trends are the increasing reliance on renewable sources in the electric grid and the increasing use of electric vehicles.  According to some projections, these trends could lead to the need for costly new power plants to meet peak loads in the evening when cars are plugged in to charge.  Overproduction of power from solar farms during the daytime would require expanded energy storage capacity so as not to waste all that generating capacity.

A new study by MIT researchers has found that it is possible to mitigate or eliminate these problems without the need for advanced technological systems and complex infrastructure.  The key elements of the strategy are the strategic placement of charging stations and the practice of delaying the onset of home charging.

Better availability of charging stations at workplaces could help to soak up peak power being produced at midday from solar power installations.  In general, placing of charging stations in strategic ways, rather than letting them spring up just anywhere, could make a big difference.

Delaying home charging to times when there is less electricity demand could be accomplished with the use of a simple app that would estimate the time to begin the charging cycle so that it finishes charging just before the car is needed the next day.  Since different people have different schedules and needs, by delaying the onset of charging appropriately, not everyone will be charging at the same time, and therefore the peak in demand would be smoothed out.

There are substantial government funds earmarked for charging infrastructure and creating that infrastructure in suitably strategic ways could make a big difference in supporting EV adoption and supporting the power grid.

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Minimizing electric vehicles’ impact on the grid

Photo, posted July 2, 2020, courtesy of Ivan Radic via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

An Iron-Air Battery Plant | Earth Wise

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Lithium-ion batteries are the standard energy source for electric vehicles, and they are also the dominant technology for storing energy in the electric grid.  However, they are not the only game in town.  There are other battery technologies that have various potential advantages over lithium-ion and some of them are getting the chance to show what they can do.

One is the iron-air battery.  Unlike lithium-ion batteries that require expensive and strategically challenging materials like lithium, cobalt, nickel, and graphite, iron-air batteries make use of one of the most common elements in the earth’s crust.

Iron-air batteries operate on a principle known as “reversible rusting”.  When discharging, the battery takes in oxygen from the air and converts iron into rust.  While charging, electrical current converts rust back into iron and the battery releases oxygen.  Batteries consist of a slab of iron, a water-based electrolyte, and a membrane that feeds a controlled stream of air into the battery. 

A Massachusetts-based company called Form Energy is building a $760 million iron-air battery storage facility in the city of Weirton in West Virginia.  Investment financing along with a $290 million government incentive package is paying for the facility. 

The facility is designed to address the need for long-duration energy storage and will be capable of storing electricity for 100 hours at competitive prices.  The battery modules will be about the size of a side-by-side washer/dryer and will contain a stack of 50 3-foot-tall cells.  Such batteries are too big and heavy for use in cars but will be cheaper and higher-capacity than equivalent lithium-ion battery systems.

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Form Energy selects West Virginia for its first iron-air battery plant

Photo credit: Form Energy

Earth Wise is a production of WAMC Northeast Public Radio

Green Steel | Earth Wise

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The Inflation Reduction Act provides $369 billion in investments to ramp up renewable energy generation and manufacturing of solar panels, wind turbines, energy storage, and electric vehicles. 

Every megawatt of solar power deployed requires 35 to 45 tons of steel.  Every megawatt of wind power uses 120 to 180 tons of steel.   Estimates are that it will take 1.7 billion tons of steel just to build all the wind turbines needed to reach net zero emissions by 2050.

This is a big problem because steel production accounts for roughly 10% of global carbon emissions and is one of the most carbon-intensive industries in the world.

Making steel is a complex and age-old process that hasn’t changed much over time.  Green steel is steel made with little or no carbon emissions.  There are a few ways to do it.  One is called the direct reduced iron method that uses green hydrogen instead of fossil fuel gas to produce iron and then a renewable-powered electric arc furnace to make the steel. 

Molten Oxide Electrolysis is an alternative green steel approach that doesn’t depend on having a green hydrogen infrastructure.  It uses electrolysis, powered by renewable energy, to separate the bonds of iron ore and produce liquid metal while releasing only oxygen in the process.

Green steel solutions rely on the availability of renewable energy, but the ultimate success of renewable energy will depend on the success of green steel.  The U.S. steel industry will leverage about $6 billion under the Inflation Reduction Act to make progress on it.

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Building tomorrow’s clean energy systems on green steel

Photo, posted October 30, 2008, courtesy of Paul Bica via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Pumped Hydro Storage In Switzerland | Earth Wise

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Pumped hydro energy storage is still by far the largest form of energy storage in the world, representing more than 90% of storage capacity worldwide.  The theory behind it is simple.  Water is pumped into an upper reservoir (that is, one at a higher elevation), and when electricity is needed, the water is allowed to flow downhill to power turbines and then is collected in a lower reservoir.   When there is excess electricity, it is used to pump water back uphill for use later.

Pumped hydro installations can’t be built just anywhere.  Geography and hydrology have to be suitable, which means high voltage transmission lines need to be constructed to link electricity sources like wind and solar farms with the storage location.  But in those situations where pumped hydro makes sense, it is a great solution to the energy storage problem.

Switzerland has just completed one of the largest pumped hydro facilities in the world.  The Nant de Drance installation makes use of the Emosson reservoir, which is an artificial lake built high in the Alps near the French border.  Over the past 14 years, 10 miles of tunnels have been dug into the mountains to connect the Emosson reservoir to the Vieux Emosson reservoir to the south.

In between the two reservoirs is a giant underground cavern where six of the largest water-driven turbines in the world are spun from the water rushing down from above.  The turbines have a capacity of 900 megawatts, making Nant de Drance one of the most powerful generating plants in Europe.  In terms of storage capacity, the installation has a maximum capacity of 20 gigawatt-hours, and can store that energy indefinitely, which is challenging for other storage technologies.

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14 Years In The Making, 20 GWh Pumped Hydro Storage Facility Comes To Switzerland (With Video)

Photo, posted September 7, 2009, courtesy of Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Lithium-Sulfur Batteries | Earth Wise

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The growing use of electric vehicles as well as energy storage systems has created a major focus on the batteries for these applications.  Lithium-ion batteries dominate these applications and the demand for the materials needed to manufacture them continues to grow.

The raw materials for these batteries include not only lithium, but also can include nickel, manganese, and cobalt. 

Sulfur has been a desirable alternative for use in lithium-based batteries for quite a while because it is an abundant element and can be extracted in ways that are safe and environmentally friendly.  However, previous attempts to create lithium batteries that combine sulfur cathodes and the standard carbonate electrolytes used in lithium-ion batteries have not been successful because of irreversible chemical reactions between intermediate sulfur products and the electrolytes.

A group of chemical engineers at Drexel University has now found a way to introduce sulfur into lithium-ion batteries that solves the stability problem and also has major performance advantages.  The new batteries have three times the capacity of conventional lithium-ion batteries, and last more than 4,000 recharges, which is also a substantial improvement.

The new battery technology involves creating a stable form of sulfur called monoclinic gamma sulfur by depositing the sulfur on carbon nanofibers.   Previously, this sulfur phase was only observed at high temperatures and was only stable for 20 or 30 minutes.  This chemical phase of sulfur does not react with carbonate electrolytes and therefore produces a battery that is chemically stable over time.

 Incorporating this sulfur into battery cathodes results in a better battery that doesn’t need any cobalt, nickel, or manganese.  It could be the next big thing in electric vehicle batteries.

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Breakthrough in Cathode Chemistry Clears Path for Lithium-Sulfur Batteries’ Commercial Viability

Photo, posted April 5, 2022, courtesy of Oregon Department of Transportation via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Record Renewable Use In California | Earth Wise

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California, the most populous state, is the second largest electricity user.  Only Texas, the second most populous state, uses more energy, in part because it consumes large amounts in refining fossil fuels. Overall, California uses about 8% of the electricity generated in the U.S.

Thus, it was a significant milestone when briefly, on April 3, a record 97.6% of the energy on California’s statewide grid came from renewable energy resources.  (The previous record of 96.4% was set just a few days earlier).

Renewable energy’s share of the power typically peaks in the spring when mild temperatures keep demand relatively low and higher sun angles drive greater solar energy production.

On April 8, a record peak solar power production was set at 13,628 megawatts just after noon.  On March 4, the state set an all-time wind generation record of 6,265 megawatts. 

California now has over 15,000 MW of grid-connected solar power and 8,000 MW of wind.  Another 600 MW of solar and 200 MW of wind are coming online by June.  The state also has about 2,700 MW of energy storage online and that will climb to 4,000 MW by June.

In 2020, 34.5% of the state’s retail electricity sales came from wind and solar sources.  Adding in hydropower and nuclear power, nearly 60% of the state’s electricity came from non-fossil fuel.  Despite the effects of drought on hydropower generation and the impact of the pandemic on the pace of renewable energy projects, California continues its dramatic transition to sustainable energy.

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Solar and wind notched records as renewables met California’s energy demand

Photo, posted September 20, 2016, courtesy of Tom Brewster Photography / BLM 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.

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.

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.

The Energy Storage Boom | Earth Wise

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Global energy storage deployment is increasing at a very rapid pace.  According to recent industry forecasts, there will be 12.4 gigawatts of new energy storage capacity online in 2021 breaking the previous annual record of 4.9 gigawatts set last year.

To understand these numbers, the world only reached 1 gigawatt of new capacity in a year for the first time in 2016.  Five years later, 1 gigawatt represents a good month.

Industry projections are that new global storage capacity will increase each year, reaching 70 gigawatts by 2030.

Almost all of this new storage capacity is in the form of batteries and most of that is lithium-ion batteries.  The largest battery storage facility in the world – the Manatee Energy Storage Center in Florida – is scheduled to be completed before the end of this year.  But there are other battery technologies that offer promise and there are other storage technologies apart from batteries.

Pumped hydroelectric storage is long established technology that still represents the largest amount of storage capacity in the world with more than 181 GW of capacity.  There is not much room for expansion of pumped hydro, which is limited to specific locations.   But it will be years before battery storage catches up to this total.

The United States and China have a large majority of energy storage capacity and projections are that the two countries will still have nearly three-quarters of the world’s total capacity in 2030.

With the ongoing rapid expansion of wind and solar power, the need for energy storage continues to grow and is the driving force for the energy storage boom.   It is not clear how it will all shake out, but energy storage is going to be a big deal from now on.

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Inside Clean Energy: Taking Stock of the Energy Storage Boom Happening Right Now

Photo, posted March 15, 2013, courtesy of Portland General Electric via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Major Funding For Novel Energy Storage | Earth Wise

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The accelerating adoption of wind and solar energy is driving a growing interest in energy storage technologies.  An electric grid dominated by intermittent power sources will need large-scale energy storage.  Grid-scale energy storage is expected to increase at least 10 times over the next decade and this will require nearly $300 billion in investments over that time period.

Much of the effort in energy storage has focused on battery storage.  But there are other storage technologies that are attracting attention and investment.

Energy Vault is a Swiss-based company specializing in gravity and kinetic energy-based energy storage.  Their technology uses a multi-headed crane to store energy generated by renewable sources by stacking heavy blocks made of composite material into a tower, capturing potential energy from the elevation gain of the blocks.  To produce electricity, the crane lowers the blocks to the ground, driving generators in the process.  The company has just raised $100 million in funding from investors. 

Malta, Inc. is an energy storage company based in Cambridge, Massachusetts that is developing an electro-thermal energy storage system.  Energy generated from renewable (or other) sources drives a heat pump to create thermal energy producing both hot and cold reservoirs.  The heat is then stored in molten salt while the cold is stored in a chilled liquid.  To generate electricity, the temperature difference between the two reservoirs is used to drive a heat engine.  Malta has recently raised $60 million in new funding including significant support from Chevron Energy Ventures.

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Energy Vault Raises $100 Million In Series C Funding

Chevron backs long-duration thermal energy storage developer Malta

Photo, posted October 16, 2019, courtesy of Jonathan Cutrer 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.

Cutting The Cost Of Energy Storage | Earth Wise

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The cost of both solar and wind power continues to drop making the two renewable energy sources the cheapest way to make electricity in more and more places.  Given the virtually inexhaustible supply of both wind and sun power, these clean electricity sources can in principle meet all our energy needs.  The hang up is that both of them are intermittent sources – the wind doesn’t blow all the time and the sun doesn’t shine all the time.

The solution to the intermittency problem is energy storage.  If energy produced by wind and sun can be stored so it can be made available for use at any time, then the goal of having 100% clean energy can be realized.

Energy storage technology has continued to improve over time and to get cheaper.  The Department of Energy recently announced a new initiative aimed at accelerating both of these trends.

The new program – called Long Duration Storage Shot –  has the goal of reducing the cost of grid-scale, long-duration energy storage by 90% within this decade.

Long-duration energy storage is defined as systems that can store energy for more than ten hours at a time.  Such systems can support a low-cost, reliable, carbon-free electric grid that can supply power even when energy generation is unavailable or lower than demand.  With long-duration storage, solar-generated power can be used at night.

The program will consider multiple types of storage technologies – electrochemical (that is: batteries), mechanical, thermal, chemical carriers, and various combinations thereof.  Any technology that has the potential to meet the necessary duration and cost targets for long-term grid storage are fair game for the program.

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DOE announces goal to cut costs of long-duration energy storage by 90%

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

Earth Wise is a production of WAMC Northeast Public Radio.

New York And Green Hydrogen | Earth Wise

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In July, outgoing New York Governor Andrew Cuomo announced plans for the state to explore the potential role of green hydrogen as part of New York’s decarbonization strategy.

Green hydrogen is hydrogen produced using renewable energy, such as wind, solar, and hydro power.  While hydrogen itself is a carbon-free fuel, most of the hydrogen produced today is made with a process called natural gas reforming which has byproducts of carbon monoxide and carbon dioxide.  As a result, the environmental benefits of using hydrogen are largely lost.  Hydrogen is the most plentiful element in the universe but extracting it for use as a fuel is not easy.

Green hydrogen is obtained by splitting water molecules into their constituent hydrogen and oxygen parts.  In principle, oxygen is the only byproduct of the process.  The main drawback of electrolysis, as this process is called, is that it is energy intensive as well as being expensive.  But if that energy comes from renewable sources, then it is a clean process.

New York’s announcement is that the state will collaborate with the National Renewable Energy Laboratory and join two hydrogen-focused organizations to inform state decision-making, as well as make $12.5 million in funding available for long duration energy storage techniques and demonstration projects that may include green hydrogen.

Green hydrogen has the potential to decarbonize many of the more challenging sectors of the economy.  Hydrogen is a storable, transportable fuel that can replace fossil fuels in many applications.  Many experts believe that the so-called hydrogen economy could be the future of the world’s energy systems.  For that to happen, green hydrogen will need to be plentiful, sustainable, and inexpensive.

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New York announces initiatives to explore green hydrogen for decarbonization

Photo, posted October 26, 2019, courtesy of Pierre Blache via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

The Plunging Cost Of Lithium-Ion Batteries | Earth Wise

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Lithium-ion batteries are the power source for phones, laptops, and electric cars.  These rechargeable batteries were first commercially introduced in 1991.  Since then, their performance has improved, and their cost has dropped tremendously.

There have been dramatic cost declines in many advanced technologies.   The price of big-screen televisions is a prime example.  Most people think of solar photovoltaic panels as the most exceptional case.  In the 1970s, solar panels cost over $100 per watt. Today, they are 20 cents a watt.

How much lithium-ion batteries have dropped in price has been somewhat unclear.  This is because much of the information about battery costs is in the form of closely held corporate data.  Most lithium-ion batteries are not sold directly to consumers but rather are built into consumer electronics and cars.  Large companies like Apple and Tesla buy batteries by the millions or manufacture them themselves, and the true costs are not publicly disclosed.

Recently, MIT researchers have carried out an extensive analysis of lithium-ion battery costs over the past three decades.  The researchers found that the cost of these batteries has dropped by 97% over that period.

It is clear that the decline in battery costs has been an enabler of the recent growth in sales of electric vehicles.  It is also clear that further declines in lithium-ion battery costs are likely to increase the batteries’ usage in stationary applications such as storing energy from intermittent green power sources like solar and wind.

The batteries have ever-improving energy density (energy stored within a given volume) and specific energy (energy stored within a given mass.)  As lithium-ion batteries continue to get better and cheaper, their role in the world continues to grow.

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Study reveals plunge in lithium-ion battery costs

Photo, posted October 26, 2020, courtesy of Ajay Suresh via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

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