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Energy storage in New York isn’t easy

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The state of New York has the ambitious goal of having 70% of its electricity come from renewable sources in 2030 and a 100% zero-emission electric grid by 2040.  Meeting these goals is becoming increasingly unlikely as the state faces multiple challenges including local opposition to projects, rising inflation, and the termination of offshore wind projects.

Solar and wind power are key elements of New York’s renewable plans, and both require battery energy storage so that excess energy can be saved when there is plentiful sun and wind so that there will be power available when nature hasn’t cooperated.

There are now over 6,000 battery storage projects in the state, mostly relatively small in magnitude.  Currently, the state has a storage capacity of about 445 megawatts, enough to power roughly 300,000-400,000 homes.  The state has a goal of having 6 gigawatts of storage by 2030, more than a dozen times more than exists today.

Most of New York’s electricity demand is downstate, in and below the Hudson Valley.  Real estate is limited and expensive and there is lots of opposition to big energy projects in the region. 

However, installing the actual battery systems themselves can be one of the easier parts of the process.  Obtaining permits from state and local authorities, buying or leasing land, negotiating with grid operators, completing environmental reviews, overcoming local opposition, and especially, connecting to the electric grid, are all challenging and very time consuming.

Meeting the state’s energy storage goals is not easy.

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Figuring Out a Battery Storage System to Fit New York’s Wind and Solar Ambitions Has Not Been Easy

Photo courtesy of NineDot Energy.

Earth Wise is a production of WAMC Northeast Public Radio

Energy droughts

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With new ways of doing things, there are always new problems.  Our energy systems are increasingly dependent upon solar and wind power.  These energy sources are free to take and aren’t going to run out, but they also depend on natural processes that are out of our control.  In particular, the sun doesn’t always shine, and the wind doesn’t always blow.

Fortunately, the two sources of energy are typically not in sync and often when one is diminished, the other can take up the slack.  But it is possible for both sun and wind to not be present, and it can even happen for an extended period of time.  This is known as a compound energy drought. There are some parts of the country where these energy droughts can last for nearly a week.

Researchers at the Pacific Northwest National Laboratory studied the phenomenon and its potential impact on the electric grid.   Looking at 40 years of weather data, the study found that the longest energy drought occurred in California for 6 days; the longest in Texas was 37 hours.

The study further investigated the possible connection between energy droughts and energy demand, again mapping historical data over the past 40 years.  The impact of an energy drought depends on how much demand for energy exists at the time.

The data from the study will provide critical insights into the design and management of multi-day energy storage facilities that can provide the resilience of the electric grid that is required.  Clearly, the storage needs in a place like California will be substantially greater than those in Texas.  As more and more of the grid depends on wind and solar power, appropriately designed and operated storage facilities will be essential.

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“Energy Droughts” in Wind and Solar Can Last Nearly a Week, Research Shows

Photo, posted February 10, 2023, courtesy of Guilhem Vellut via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Energy storage with iron-air batteries

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The Cambridge Energy Storage Project in Cambridge, Minnesota will be the first commercial deployment of iron-air battery technology.  Developed by startup company Form Energy, the battery system will provide 1.5 MW and 150 MWh of multi-day energy storage.

Iron-air batteries are based on the principle of reversible rusting.  When discharging, the battery releases energy by breathing in oxygen from the air and converting iron metal to rust.  When charging, the battery takes up electrical current that converts rust back into iron and breathes out oxygen.

An individual iron-air battery module is about the size of a washer/dryer set and contains about 50 individual cells filled with a water-based, non-flammable electrolyte.  For a utility-scale system like that being built in Cambridge, modules are grouped together in enclosures and hundreds of enclosures grouped together in megawatt-scale power blocks.  A one-megawatt low-density system would take up about half an acre of land.  High-density systems would be capable of producing more than 3 MW per acre. 

The technology has lower costs compared to lithium-ion battery technology but may be best suited as complementary with it since lithium-ion is primarily used for short-duration energy storage while air-iron can store energy for several days.

The system is expected to be operational by late 2025.  Great River Energy, the operator of the system, plans to conduct a multi-year study to evaluate the system’s performance and potential for broader development. 

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Minnesota co-op breaks ground on multi-day energy storage project

Photo courtesy of Form Energy.

Earth Wise is a production of WAMC Northeast Public Radio

Giant batteries in the Earth

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The wind and the sun are inexhaustible sources of energy, and we are tapping into them to produce electricity at a growing rate around the world.  But neither of them is always available when we need them.  When the sun isn’t shining and the wind isn’t blowing, they don’t work.

An opposite problem also exists.  When our energy needs are low, but it is sunny or windy, solar and wind power are all dressed up with nowhere to go.  Energy storage is the answer to both of these problems.   When there is excess generation, store the energy for later use.  When there is need for energy and not enough is being generated, tap into the energy that is stored.

Giant banks of lithium-ion batteries are the rapidly growing form of energy storage, and they are increasingly providing resilience in the electric grid.  But battery storage is short-term energy storage.  Even the largest battery banks can only provide a few hours of electricity. 

So, there is a real need for “long-duration energy storage” – systems that provide at least 10 hours of backup power and sometimes much more – for the grid to be fully reliable.

Pumped hydro storage, which uses water from elevated reservoirs to drive turbines, has been around for a long time.  Historically, this is the largest form of energy storage in the world.  Other methods include pumping compressed air into underground caverns or lifting massive blocks into elevated positions.  All of these techniques use excess electricity to place things like water, air, or cement into a position where they can be used to drive electrical generators.

The grid of tomorrow will store energy in giant battery banks, but also in the ground, in reservoirs, and in large structures.

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How giant ‘batteries’ in the Earth could slash your electricity bills

Photo, posted March 21, 2024, courtesy of Sandra Uecker/USFWS via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

A better way to extract lithium

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Lithium is the critical component in the batteries that power phones and computers, electric cars, and the systems that store energy generated by solar and wind farms.  Lithium is not particularly rare, but it is difficult and often environmentally harmful to extract from where it is found.

Traditional ore sources are increasingly difficult and expensive to mine.  The largest known deposits of lithium are in natural brines – the salty water found in geothermal environments.  These brines also contain other ions like sodium, potassium, magnesium, and calcium, and efficiently separating out the lithium is extremely challenging.

Traditional separation techniques consume large amounts of energy and produce chemical waste, particularly hazardous chlorine gas.  These techniques typically suffer from poor selectivity; that is, the process is interfered with by the other ions present in natural brines.

A team of researchers at Rice University has developed a three-chamber electrochemical reactor that improves the selectivity and efficiency of lithium extraction from brines.  The middle chamber of the reactor contains a specialized membrane that acts as a barrier to chloride ions, preventing them from getting to the electrode area where they can form chlorine gas.

The new reactor has achieved a lithium purity rate of 97.5%, which means the setup can effectively separate lithium from other ions in the brine and allow the production of high-quality lithium hydroxide, the key material for battery manufacturing. 

The Rice University reactor design has the potential to be a game changer for lithium extraction from geothermal brines.

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‘Game changer’ in lithium extraction: Rice researchers develop novel electrochemical reactor

Photo, posted October 21, 2023, courtesy of Simaron via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

How much energy storage is needed?

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Energy storage is a critical aspect of modern energy systems as they move towards heavy dependence on renewable sources such as solar and wind that don’t produce energy at the same rate all the time.  Excess energy generated by solar power needs to be stored for when the sun isn’t shining; excess wind energy needs to be stored for when the wind isn’t blowing.  But how much storage capacity does the energy system need to have?

Researchers at North Carolina State University have developed a model that can be used to project what a system’s storage needs would be if it were to shift entirely to renewable sources.

The model accounts for how energy production from renewable sources would change during different times of day and different times of the year.  For example, there is much more solar energy generation in the summer when the days are longer, and it is sunny more often.

There is also the issue of short-term vs. long-term energy storage.  Short-term energy storage does not refer to how long a storage device can store the energy.  It refers to how long it can provide power at its rated level.

The study focused on Italy’s energy system, which has suffered in recent years because it had difficulties in obtaining natural gas from Russia due to the invasion of Ukraine.

As the world moves increasingly towards renewable power sources, energy systems need to be able to account for the variability of those sources.  The new model offers policymakers critical information for use in energy system planning.

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Model Projects Energy Storage Needs for Fossil Fuel-Free Energy System

Photo, posted October 28, 2016, courtesy of Daxis via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Much more energy storage for New York

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As solar and wind power play an ever-growing role in the electricity grid, the need for energy storage also grows.  Even if sun and wind can provide more energy than is needed at a particular time, they can’t provide it at all times.  The ability to store excess energy waiting in reserve for when the sun and wind are not providing it is essential to avoid the need for burning fossil fuels to take up the slack.

The New York State Public Service Commission has announced that it has approved a new framework for the state to have in place a nation-leading six gigawatts of energy storage by 2030.  This represents at least 20% of the peak electricity load of New York State.

An extensive set of recommendations to expand New York’s energy storage programs describe cost-effective ways to unlock the rapid growth of renewable energy across the state as well as to bolster the reliability of the grid.  The buildout of storage deployment is estimated to reduce projected future statewide electric system costs by nearly $2 billion.  New York has previously established goals to generate 70% of its electricity from renewable sources by 2030 and 100% zero-emission electricity by 2040.

The new roadmap includes programs to procure an additional 4.7 gigawatts of new energy storage projects across large-scale, retail, and residential energy storage sectors across the state.  These future procurements, when combined with the 1.3 gigawatts already being procured or under contract, will allow the State to achieve the 6-gigawatt goal by 2030.

Energy storage plays a critical role in decarbonizing the grid, reducing electricity system costs, and improving the reliability of the electricity system.

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New York approves plan to add six gigawatts of energy storage by 2030

Photo courtesy of NineDot Energy.

Earth Wise is a production of WAMC Northeast Public Radio

Clean energy investment at record levels

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According to a new study by the International Energy Agency, global clean energy investment will be nearly twice that of fossil fuels this year.  The surging funding for clean energy is being driven by a combination of lower costs for renewable energy and by improving supply chains.

In 2024, the world’s investments in energy are expected to surpass $3 trillion dollars for the first time.  About $2 trillion of that will be directed at green technologies that include renewable power sources, grids, and energy storage; electric vehicles; low-emission fuels; nuclear power; and heat pumps and efficiency improvements.  The remaining amount of just over $1 trillion will fund oil, gas, and oil projects.

The record growth in clean energy investments is taking place in spite of challenging economic conditions related to high interest rates, which demonstrates the momentum behind the global energy transition.

The IEA report does caution that there are big imbalances and shortages in energy investment in various places around the world.  For example, there is a low amount of green energy spending in developing and emerging economies outside of China.  Countries like Brazil and India are leading the way for this sector by having investments in excess of $300 billion.

More money is currently going into solar power development than all other electricity generation technologies combined.  In 2024, solar photovoltaic power investment is set to grow to $500 billion as the falling price of solar modules spurs new investments.

The largest renewable investments will come from China at $675 billion, followed by Europe and the U.S. at $370 billion and $315 billion, respectively.

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Global Clean Energy Investment Will Nearly Double That of Fossil Fuels in 2024: IEA Report

Photo, posted October 2, 2015, courtesy of John Englart via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

California renewable energy

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California has aggressively pursued the use of renewable energy, particularly solar and wind power.  Last year, renewables supplied 54% of the state’s electricity needs.  This year, California has been achieving some remarkable milestones with its renewable energy.

As of May 26th, California had produced more than 100% of its electricity demand with wind, solar, and hydropower for parts of 51 straight days and 75 out of 81 days.  On May 25th, California’s grid ran entirely on renewable energy for 10.1 straight hours and renewables provided 83% of the state’s electricity for the entire 24-hour period.  California uses more electricity than any other state apart than Texas, which uses more than half its energy for operating refineries and petrochemical plants.

Excess power in California is either exported to other states or is used to charge up the state’s growing arrays of energy storage batteries.  California has the largest grid-connected battery storage facility in the world, located in Kern County.  The facility can store nearly 3,300 megawatt-hours of energy.

The ability to produce more power than the state needs occurs during the day when the sun is shining, and when many people are not at home.  At night, demand goes up and solar power is not available.  But as the quantity of energy storage available continues to grow along with additional solar installations, California will ultimately be able to wean off of the gas-fueled power plants it predominantly uses at night.

According to some experts, California may operate entirely on renewables and battery storage as soon as 2035. 

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California exceeds 100% of energy demand with renewables over a record 30 days

Photo, posted January 11, 2016, courtesy of Jared Eberhardt via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Gravity storage on the grid

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For the past several years, the Swiss-based company Energy Vault has been developing an energy storage system based on the principle of using mechanical devices to lift heavy concrete blocks into stacks using power generated by wind turbines or other renewable sources.  When energy is needed, the blocks are lowered back to the ground, spinning generators in the process.

The principle of storing energy in the form of gravitational potential energy is the most widely used form of energy storage in existence but usually works by pumping water into a reservoir at higher elevation and then letting the water come back down when energy is needed.

Energy Vault has built a grid-scale 100 MWh gravity storage system in Rudong China.  It has now been successfully tested with charging and discharging and has been commissioned. Pending final provincial and state approvals, it will be the world’ first commercial, utility-scale non-pumped hydro gravity energy storage system.

The Rudong project teamed Energy Vault with environmental management company CTNY and Atlas Renewable.  Energy Vault has extended its license agreement with Atlas Renewable to 15 years.  CTNY has announced plans for eight additional deployments of the Energy Vault gravity storage system across China, representing more than 3.7 GWh of energy storage.

Energy Vault’s technology has attracted a fair amount of skepticism from parts of the energy community based on the environmental burdens of concrete as well as durability issues.  It appears the technology will have significant real-world testing in China, which should provide unambiguous answers to everyone’s questions.

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Energy Vault Announces Successful Testing and Commissioning of First EVx 100 MWh Gravity Energy Storage System by China Tianying, Extension of Atlas Renewable Licensing Agreement to 15 Years

Photo, posted December 21, 2018, courtesy of Nancy Winfrey via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

A giant underground battery

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Two up-and-coming energy technologies are coming together near a tiny town in central Utah.  Outside of the town of Delta, population 3,600, two caverns, each as deep as the Empire State Building, are being created from an underground salt formation to be used to store hydrogen gas.  The gas will be used as a fuel in a new electricity generation plant.

The plant will replace an aging local coal-fired power plant.  The new plant will burn a mixture of natural gas and hydrogen – green hydrogen produced without emitting greenhouse gases. To produce the hydrogen, the facility will operate 40 giant electrolyzers that will use excess solar and wind power generated at times of low demand to split water molecules into hydrogen and oxygen.

The caverns were created by a process called solution mining in which high-pressure water is pumped down into salt deposits that are dissolved. The resulting caverns are 200 feet in diameter and 1,200 deep and lie 3,000 to 4,000 feet below the surface.  Hydrogen cannot escape through the thick salt layers.

The amount of energy that can be stored in the form of hydrogen fuel in these caverns is massive – far more than all the battery storage installed in the U.S. to date.  Chevron has a majority stake in one of the projects and will supply the natural gas.  The facility is expected to go online in 2025.

While this will produce far fewer emissions than existing coal plants, it is not carbon-free.  Currently, turbine technology cannot operate with pure hydrogen fuel.  The Delta plant will run on only 30% hydrogen.  The hope is that turbine technology will improve in the future and permit operation on pure hydrogen.

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A Huge Underground Battery Is Coming to a Tiny Utah Town

Photo, posted September 9, 2013, courtesy of Scott via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Sodium-ion batteries

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The transition away from fossil fuels is driving a rapidly increasing need for batteries.  Both electric vehicles and energy storage for the electric grid are enormous consumers of batteries.  At present, lithium-ion batteries are almost universally used for these purposes.  They have been getting better all the time and cheaper all the time and are likely to be the answer for the foreseeable future.  But they are not perfect.

Lithium is only found in a relatively small number of places and mining and extracting it is fairly expensive and environmentally unfriendly.  Lithium-ion batteries also frequently contain cobalt, which has its own set of problems.  There are also safety issues related to the flammability of lithium-ion batteries. 

As a result, there continue to be numerous efforts to identify and develop alternative battery technologies.  One of these is sodium-ion batteries, which are similar in many ways to lithium-ion batteries but in which sodium replaces lithium as the cathode material.

Sodium is extremely common – it’s found in ordinary salt – and sodium-ion batteries have a high energy density and are easy to produce.  They should have a long lifetime and have a more benign environmental impact than lithium-ion.  Many companies and researchers are working on sodium-ion batteries and are making good progress.

A study by Chalmers University in Sweden looked at the potential for sodium-ion batteries and found that the batteries are particularly promising for use in energy storage even in their current state of development and could eventually be used in cars.  Whether sodium-ion batteries can be good enough and cheap enough quickly enough to give lithium-ion a run for its money remains to be seen.

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Resource-efficient and climate-friendly with sodium-ion batteries

Photo, posted March 12, 2013, courtesy of Chris Hunkeler via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

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

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WAMC/Northeast Public Radio is a regional public radio network serving parts of seven northeastern states (more...)