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Wave energy in LA

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Ocean waves form as wind blows over the surface of open water.  Globally, waves contain tremendous amounts of energy.  Theoretically, the energy generating potential of waves off the coasts of the U.S. would meet more than 60% of the country’s electricity needs.  There are a variety of methods and technologies for tapping into this energy source, but none have reached the point of commercial adoption to date.  There are many problems that remain to be solved.

Eco Wave Power, a wave energy company, announced that it has received the necessary permit from the U.S. Army Corps of Engineers to operate the first onshore wave energy installation in the United States.  The installation will be at the Port of Los Angeles at the facilities of AltaSea, a public-private ocean institute that conducts research on food and energy supply, climate change, and ocean exploration.

The system will utilize eight of Eco Wave Power’s energy floaters that will be installed on the piles of an existing concrete wharf structure on Municipal Pier One.  The system will also include an energy conversion unit enclosed in two shipping containers and connected to the floaters.  The installation is expected to be completed by the end of the first quarter of this year.

Floaters draw energy from waves by using their rising and falling motion to generate electricity. The bobbing motion of the floaters compresses and decompresses hydraulic pistons.  These transmit hydraulic fluid into land-based accumulators that build up pressure.  The pressure rotates a hydraulic motor, which then operates a generator, producing electricity.

The project is a collaboration on the development of wave energy in the Port of Los Angeles between Eco Wave Power and Shell Marine Renewable Program.

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Eco Wave Power secures final USACE permit for its first U.S. wave energy project

Photo courtesy of Eco Wave Power.

Earth Wise is a production of WAMC Northeast Public Radio

Making hydrogen using bioengineering

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Hydrogen has great potential for helping society to reach net-zero emissions.  The problem is that the most economical and established production methods for hydrogen depend heavily on fossil fuels and result in roughly a dozen kilograms of carbon dioxide emissions for every kilogram of hydrogen produced.

The carbon-free way to produce hydrogen is by splitting water into its component elements.  This process generally requires the use of catalysts and lots of energy.

Researchers at the University of Oxford are developing a synthetic biology approach to the production of so-called green hydrogen.  The idea is to replace expensive, exotic metal-based catalysts with a highly-efficient, stable, and cost-effective catalyst based on genetically-engineered bacteria.

There are specific microorganisms that can naturally induce the chemical reaction that reduces protons to hydrogen by the use of hydrogenase enzymes.  While these reactions do occur naturally, they are limited to low hydrogen yields.

The Oxford researchers genetically engineered the bacterium Shewanella oneidensis by inserting a light activated electron pump called Gloeobacter rhodopsin as well as adding nanoparticles of graphene oxide and ferric sulfate.  All of this tinkering with the bacterium resulted in a ten-fold increase in hydrogen yield.

The researchers believe that their system, based entirely on biological methods rather than traditional chemical approaches, could be scaled up to produce ‘artificial leaves’ that, when exposed to sunlight, would immediately begin producing hydrogen.  The Oxford work was published last summer in the Proceedings of the National Academy of Science.

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A green fuels breakthrough: bio-engineering bacteria to become ‘hydrogen nanoreactors’

Photo, posted July 27, 2016, courtesy of Blondinrikard Froberg 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

New approaches to nuclear power

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The US is the world’s largest user of nuclear power.  Its 94 reactors supply nearly 19% of the country’s electricity. But the number of U.S. reactors has steadily fallen over the past 30 years and new nuclear power plants are a real rarity.  The reasons are a combination of perceived dangers following several nuclear accidents and the increasing costs associated with building plants that can meet a growing number of regulatory requirements.

There are recent developments associated with new advanced reactor technologies that may lead to a resurgence in the use of nuclear power.  Bill Gates’ energy company TerraPower is developing nuclear reactors that use sodium instead of water for cooling.  Such reactors operate at lower pressures and higher temperatures.  

Meanwhile, Kairos Power, a California-based energy company, has entered into an agreement with Google to build multiple small modular nuclear reactors that will supply electricity to that giant tech company.  The modular reactors use a molten-salt cooling system combined with a ceramic, pebble-type fuel in order to transport heat to a steam turbine to generate power.  The novel design of these reactors can reduce construction timelines, allow deployment in more places, and make final project delivery more predictable.

Surveys indicate that a majority of Americans favor the use of nuclear power, which has the advantages that it doesn’t create greenhouse gas emissions and can run 24-7.  But traditional nuclear power plants are too expensive and have too many potential problems.  These new nuclear power technologies may be the answer for allowing nuclear power to play an important role in the future energy system.

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New nuclear clean energy agreement with Kairos Power

Photo, posted May 16, 2016, courtesy of Steve Jurvetson via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Solar-powered desalination

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People in remote, low-income regions far from the ocean often need to meet their water needs from groundwater and groundwater is becoming increasingly saline due to climate change.  Desalination of brackish groundwater is a huge and largely untapped source of drinking water, but there are challenges in making the process efficient and reliable.

Engineers at MIT have developed a solar-powered desalination system that requires no batteries or external power sources and is capable of producing large quantities of clean water despite the variations of sunshine throughout the day.

The system is based on the process of electrodialysis and consists of water pumps, an ion-exchange membrane stack, and a solar panel array.  What is unique about it is that it makes use of sensors and a control system that predicts the optimal rate at which to pump water through the system based on the output of the solar panels.  As a result, it uses nearly all of the electricity generated to produce clean water and does not need stored or grid-based energy.

The MIT engineers tested a community-scale prototype on groundwater wells in New Mexico over a six-month period.  The system harnessed on average over 94% of the electricity generated by its solar panels and produced as much as 5,000 liters of water per day despite large variations in weather and sunlight.

The new renewable-powered, battery-free system could provide much-needed drinking water at low cost, especially for communities where access to seawater and to grid power are limited.  The team plans to further test and scale up the system so it can supply larger communities and even whole municipalities with low-cost drinking water.

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Solar-powered desalination system requires no extra batteries

Photo courtesy of Shane Pratt.

Earth Wise is a production of WAMC Northeast Public Radio

Big Food and greenhouse gas emissions

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The global food system is responsible for as much as 40% of human-generated greenhouse gas emissions. The investor advocacy group Ceres has tracked whether the 50 largest North American food and agriculture companies have set targets to lower their emissions and whether doing so has actually resulted in lower emissions.

The emissions from food and agriculture companies are grouped into three so-called scopes.  Scope 1 are emissions from a company’s direct operations.  Scope 2 are emissions from its energy use.  Scope 3 are emissions from a company’s supply chain:  from the farmers who grow crops, raise cattle, and otherwise provide necessary items for a company’s final products.  In the food industry, the scope 3 category is responsible for about 90% of overall emissions.

Of the 50 food companies studied, 23 reduced their scope 1 and scope 2 emissions over the past 2 years, but only 12 reduced their scope 3 emissions.  Companies have more control over their scope 1 and scope 2 emissions. 

Reducing scope 3 emissions is more difficult.  And most companies haven’t set scope 3 reduction targets. 

The findings of the study suggest that reducing scope 3 emissions is especially difficult for companies whose supply chains are linked to carbon-intensive commodities, like meat, or crops linked to deforestation or land-use change, both of which result in increased emissions.

In March, the Securities and Exchange Commission finalized rules requiring companies to disclose their climate risk to regulators, increasing the visibility of the food industry emissions issue.

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North America’s Biggest Food Companies Are Struggling to Lower Their Greenhouse Gas Emissions

Photo, posted October 13, 2011, courtesy of the United Soybean Board via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Water from thin air

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The Earth’s atmosphere contains enormous amounts of water.  Being able to efficiently and economically extract some of it to provide drinking water would be extremely beneficial to the billions of people across the globe who face chronic water shortages.

There are existing technologies for atmospheric water harvesting – or AWH.  But there are downsides associated with size, cost, and efficiency.   A new device developed by mechanical engineering researchers at the University of Utah has the potential to provide a new drinking water source in arid places.

The device is a compact, rapid-cycling, fuel-fired AWH device.  It relies on adsorbent materials that draw water molecules out of non-humid air and then applies heat to release those molecules into liquid form.

Hygroscopic materials are those that have an affinity for water and soak it up at every opportunity.  Such materials are used, for example, in disposable diapers.  The Utah device makes use of metal organic frameworks, which have enormous amounts of surface area on the molecular scale.

The initial work on the Utah device targeted a small compact water generation unit for soldiers in the field.  Instead of lugging around a large canteen filled with water, the small unit can produce water on demand.  The prototype was able to produce 5 liters of water per day per kilogram of adsorbent material.  Within three days in the field, the system outperforms packing water.  The heat required to precipitate the liquid water was provided by a standard-issue Army camping stove.

Non-military needs are the ultimate application for the device.  The researchers have applied for a patent for what they hope will be a potential solution to a persistent global problem.

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Producing water out of thin air

Photo, posted August 9, 2012, courtesy of Enid Martindale 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

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

Cyber protection for apple orchards

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Spring frosts represent a real danger for apple orchards.  The changing climate has brought about periods of unusually warm weather at times early in the year that have caused trees and other flowering plants to bloom early.  For apple growers, this has made their orchards more susceptible to the damaging effects of extreme cold events.

Apple growers attempt to prevent this damage by heating the canopies of their orchards, but these efforts tend to be inefficient.  Applying heat is one of the most effective methods to prevent apple flower bud damage, but it is difficult to determine when and where to apply heat in orchards.

Researchers at Penn State University have developed a frost-protection cyber-physical system that autonomously makes heating decisions based on real-time temperature and wind-direction data.  Their system includes a temperature-sensing device, a propane-fueled heater that adjusts the direction where it provides heat, and an unmanned ground vehicle that moves the system through an apple orchard.

The results of tests of the system were published in the journal Computers and Electronics in Agriculture, and the findings show that it greatly reduced damage to apple tree buds in tests conducted at low temperatures, doubling or tripling the amount of time that trees were protected.

The equipment used for the study mostly consisted of off-the-shelf parts and cost about $5,000, most of which was for the vehicle.   The researchers envision that even a very large orchard could be protected by multiple units guided by an aerial drone monitoring canopy temperatures. Further research will aim to bring the technology to point where it can enter the marketplace and be available to apple growers.

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Cyber-physical heating system may protect apple blossoms in orchards

Photo, posted September 6, 2017, courtesy of Sue Thompson via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Is the Amazon rainforest nearing a tipping point?

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The Amazon rainforest is the largest rainforest in the world, covering more than 2.5 million square miles.  More than three million species live in the rainforest, which constitutes approximately 10% of the world’s known biodiversity.  The Amazon rainforest’s biodiversity is so rich that scientists are still discovering new species all the time. 

The Amazon rainforest absorbs huge amounts of carbon dioxide from Earth’s atmosphere, making it a key part of mitigating climate change.  But the amount of carbon dioxide absorbed by the Amazon rainforest today is 30% less than it was in the 1990s. 

Deforestation of the Amazon rainforest remains a major problem. Cattle ranching is the leading cause of deforestation, but industrial activities, such as the mining of oil and gas, copper, iron, and gold, are also to blame.

According to a new study recently published in the journal Nature, global warming may be interacting with regional rainfall and deforestation to accelerate forest loss in the Amazon.  In fact, it may be pushing the rainforest towards a partial or total collapse. 

The study, which was led by researchers from Federal University of Santa Catarina in Brazil and the University of Birmingham in the U.K., has identified the potential thresholds of these stressors, and highlighted how their combined effects could produce a tipping point for the Amazon rainforest. 

The findings are important because the Amazon rainforest plays a vital role in the global climate system.  By identifying the most important stressors on the rainforest environment, the researchers hope they can develop a plan to keep the Amazon rainforest resilient.

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Is the Amazon forest approaching a tipping point?

Photo, posted July 2, 2017, courtesy of Anna & Michal via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Floating Sea Farms | Earth Wise

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Researchers at the University of South Australia have designed a self-sustaining solar-driven system that turns seawater into fresh water and grows crops without any involvement.  In theory, such a system could help address the growing problems of freshwater shortages and inadequate food supplies as the world’s population continues to increase.

The system can be described as a vertical floating sea farm.  It is made up of two chambers:  an upper layer similar to a greenhouse and a lower chamber for water harvesting.

Clean water is supplied by an array of solar evaporators that soak up seawater, trap the salts in the evaporator body and, heated by the sun, release clean water vapor into the air which is then condensed on belts that transfer the water into the upper plant growth chamber.

The researchers tested the system by growing broccoli, lettuce and bok choi on seawater surfaces without maintenance or additional clean water irrigation.  The system was powered entirely by solar light.

The design is only a proof-of-concept at this point.   The next step is to scale it up using an array of individual devices to increase plant production. 

The futuristic potential for such technology would be huge farm biodomes floating on the ocean.  The UN estimates that by 2050, nearly 2.5 billion people are likely to experience water shortages while the global supply of water for irrigation is expected to decline by 19%.  Nearly 98% of the world’s water is in the oceans.  Harnessing the sea and the sun to address growing global shortages could be the way to go.

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Floating sea farms: a solution to feed the world and ensure freshwater by 2050

Photo, posted February 11, 2015, courtesy of Ed Dunens via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Grid-Scale Gravity Energy Storage | Earth Wise

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As wind and solar energy play a growing part in our energy system, the need for grid-scale energy storage is growing as well.  An historic form of energy storage and still the largest in installed capacity is pumped hydro storage, which makes use of the potential energy contained in having water sitting at a higher elevation where it can be released downward to operate turbine generators.  This is an effective system but is limited to places where geography cooperates.

For the past five years, a company called Energy Vault has been developing a system that uses the same principle to generate electricity but instead of pumping water to a higher elevation, it uses mechanical devices to lift heavy objects such as concrete blocks to an appropriate height.  Lowering the blocks back to the ground drives generators.

To date, Energy Vault has only built demonstration systems with a fraction of the storage capacity needed for grid-scale operation. Their EV1 Tower in Switzerland was successfully grid interconnected in 2020 and demonstrated round-trip efficiency (the fraction of the energy stored that was produced by the generators) above 75%.  Their improved EVx system is expected to do better than 80%.

This year the company, along with partners Atlas Renewable and China TIanying, is now in the first phases of commissioning a grid-scale system located outside of Shanghai, China.  The 25-MW system is built adjacent to a wind farm and a national grid interconnection site

This is the first grid-scale gravity energy storage system and is expected to be fully online in the fourth quarter of this year.  A second, similar system is now under contract to be built elsewhere in China.

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First grid-scale gravity energy storage system undergoes commencement in China

Photo courtesy of Energy Vault.

Earth Wise is a production of WAMC Northeast Public Radio

Cheaper Carbon Capture | Earth Wise

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As the years roll by without sufficient progress in reducing carbon dioxide emissions, the need for technologies that can capture CO2 from its sources or remove it from the air becomes stronger and stronger.  People have developed various ways to capture carbon dioxide, but to date, they generally suffer from some combination of being too costly or not being able to scale up to the necessary magnitude.

Scientists at the Pacific Northwest National Laboratory in Richland, Washington recently announced the creation of a new system that they claim is the least costly to date that captures carbon dioxide and turns it into a widely-used chemical: methanol.

Technologies that simply capture carbon dioxide that then needs to be stored in some secure location are difficult to implement from a cost perspective.  The PNNL researchers believe that turning CO2 into methanol can provide the financial incentive for widespread implementation.   Methanol can be used as a fuel, a solvent, or an important ingredient in plastics, paint, construction materials, and car parts.

The system is designed to be installed in fossil fuel-fired power plants as well as cement and steel plants.  Using a capture solvent developed by PNNL, the system grabs carbon dioxide molecules before they are emitted and converts them into methanol. Creating methanol from CO2 is nothing new, but capturing the carbon dioxide and converting into methanol in one continuously flowing system is new.

More work is needed to optimize and scale the process and it may be several years before it is ready for commercial deployment.

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Scientists Unveil Least Costly Carbon Capture System to Date

Photo, posted November 25, 2022, courtesy of Massachusetts Department of Environmental Conservation via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Tracking Small-Scale Fishers | Earth Wise

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About half of all global seafood is caught by artisanal fishers.  These are individuals who operate on a small scale – often on a subsistence level – and typically fish only a short distance from shore.  Over 85% of the estimated 2.5 million motorized fishing vessels in the world are less than 12 meters in length.  Compared with large-scale commercial fishing operations, these enterprises are very small.  However, they are essential to the food security and livelihoods of their communities.   Because of their sheer numbers, artisanal fishers are an important sector to monitor, manage, and advocate for.  They may be small-scale, but their importance and impact are huge.

Large ships make use of vessel tracking systems, which were originally conceived to prevent maritime collisions.  Over time, VTS technology has become useful for other purposes including monitoring fishing activity in sensitive marine areas and looking out for forced labor on the high seas.

Among small fishing vessels, only an estimated 0.4% are equipped with VTS technology.  So, a massive number of vessels accounting for a big part of the global catch cannot be monitored.

Researchers at UC Santa Barbara surveyed hundreds of artisanal fishers in Indonesia and Mexico to see if they were willing to pay to participate in a VTS program, or participate for free, or be paid to participate.  Having the equipment would provide multiple benefits to the fishers including increased safety and better fisheries management.  Two-thirds of the survey participants said they were willing to pay for the technology.  The study is the first effort to explore the potential for encouraging wide adoption of VTS technology among artisanal fishers.

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Tracking Small-Scale Fishers

Photo, posted November 30, 2014, courtesy of Bernard Spragg 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.

Keeping Venice From Flooding | Earth Wise

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Since 2003, Venice Italy has been building a system of mobile gates at three inlets to its famous lagoon.  The project is called MOSE, the Italian word for Moses, but is actually an acronym for the Italian words meaning Experimental Electromechanical Module.  

The 78 mobile gates are metal box structures that sit at the bottom of inlet channels.  When a high tide is predicted, compressed air is pumped into the structures.  The air causes the barriers to rise up to the surface and block the flow of the tide, thereby preventing water from flowing into the lagoon.

The system had an important test on November 3 when water levels were predicted to rise four-and-a-half feet above normal at high tide and strong winds were blowing.  Water at that level is enough to flood 60% of the city, including the famous St. Mark’s Square, which is unfortunately the lowest part of the city.

Activating the flood gates proved to be successful.  Even though high tide water levels in fact rose 4.3 feet in the surrounding Adriatic Sea, they only reached 2.7 feet in Venice, which was enough to prevent significant flooding.

Rising sea levels have led to increasingly frequent floods in Venice.  In 2019, before the MOSE system was available for use, there were more than 25 high-water events swamping Venice, including one in November of that year that was the second worst on record.

Some researchers have calculated that the system will need to be closed for as much as 3 weeks a year by the end of the century even if emission reductions are reasonably effective.  If they aren’t, the gates may be closed for at least two months a year by 2080.

After many years of delays, setbacks and controversies, the system is finally operational.

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Venice Holds Back the Adriatic Sea

Photo, posted October 25, 2014, courtesy of Pedro Szekely 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.

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.

Wireless EV Charging | Earth Wise

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Michigan, historically the focus of the American auto industry, has announced a new initiative to develop the nation’s first wireless charging infrastructure on a public road.  The Inductive Vehicle Charging Pilot is a partnership between the Michigan Department of Transportation and the Office of Future Mobility and Electrification.

The idea is to deploy an electrified roadway system that allows electric buses, shuttles, and vehicles to charge while driving, allowing them to operate continuously without stopping to charge.  In principle, such electrified roadways have the potential to accelerate the adoption of electric vehicles and turn public streets into safe and sustainable shared energy platforms.  This is especially valuable for drivers who might not have easy access to conventional charging facilities.

The pilot program is seeking proposals to design, fund, evaluate, iterate, test, and implement an inductive charging system along a one-mile stretch of state-operated roadway in Michigan.

The basic concept is to embed coils in a road that will convey electricity to cars outfitted with coils of their own.  It is much like the wireless charging pads used to power up smartphones.  Indiana is pursuing a similar project in the next couple of years.

Clearly driving through a one mile stretch of roadway for minute or two is not going to provide a whole lot of energy by whatever coupling mechanism is used. Scaling up the technology represents a significant challenge at the very least.  How practical such a scheme is from both a technology and an economic perspective remains to be seen.  In any case, it is interesting to see that states are looking at various alternatives for providing access to charging infrastructure to the growing population of electrified vehicles.

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Web Links

Governor Whitmer Announces Initiative for Nation-Leading Wireless EV Charging Infrastructure in Michigan

Photo, posted September 6, 2020, courtesy of Chris Yarzab via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

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