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Colorful Solar Panels | Earth Wise

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More and more buildings and public spaces are incorporating solar panels and not only just on rooftops.  Some buildings are incorporating power-generating structures all over their facades.

Using solar panels in this way puts some design constraints on buildings because solar panels are typically a deep black color.  This is because solar panels need to absorb light and making them any other color decreases their ability to do so and generate power.  But the problem is that people don’t necessarily want a black building.

One alternative to traditional solar panel design is to use structural sources of color that include microscopic shapes that only reflect specific light frequencies, like the scales on butterfly wings.  But this approach generally leads to iridescence – which might not be what is wanted – and is often quite expensive to implement.

A team of researchers at a university in Shanghai has now demonstrated a way to give solar panels color that is easy and inexpensive to apply and that does not reduce their ability to produce energy efficiently.

The technique involves spraying a thin layer of a material called a photonic glass onto the surface of solar cells.  The photonic glass is made of a thin, disorderly layer of dielectric microscopic zinc sulfide spheres.  Even though most light can pass through the photonic glass, certain colors are reflected back, depending on the sizes of the spheres.  By varying that size, the researchers created solar panels that were blue, green, or purple with only a very small drop in solar panel efficiency.

The solar panels made this way maintained their color and performance under durability testing.  With this new technology, there may soon be colorful solar panels on our buildings.

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Colorful solar panels could make the technology more attractive

Photo, posted December 15, 2021, courtesy of Pete via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Solar Windows | Earth Wise

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Solar windows are an attractive idea.  It is very appealing to have the vertical surfaces on the outside of almost any building generate electricity.  The challenge is to have a transparent window be able to function as an efficient-enough solar panel.

Most conventional solar panels use silicon solar cell technology, which is not based on a transparent material.  Transparent solar cells use dye-sensitized technology, which has been the subject of research for decades but has yet to achieve widespread use.

Researchers at the University of Michigan have recently published work on a new process to manufacture solar windows that can be large (over six feet in each dimension) and efficient at electricity production.

The windows make use of dye-sensitized cells which are connected to lines of metal so small that they are invisible to the naked eye.  The individual cells are fairly small but the connection technology allows the construction of large windows.

The solar window has an efficiency of 7%, meaning 7% of incoming sunlight energy is converted to electricity.  The researchers believe that 10% efficiency should be attainable with their technology.  Conventional solar panels have efficiencies of 15% or more.

However, the goal is not necessarily to compete with silicon solar panels.  The real opportunity is to be able to generate electricity when rooftop solar is not practical or to produce additional electricity even when there is already a solar roof.

Going forward, the goals of solar window development are to increase efficiency and to reduce costs to where installing the windows is economically attractive.  Estimates are that the windows currently would cost about twice as much as a conventional window but would pay for the difference in two to six years depending on such things as the level of sun exposure.

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Inside Clean Energy: What’s Hotter than Solar Panels? Solar Windows.

Photo, posted April 17, 2017, courtesy of Shelby Bell via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Rooftop Solar Taking Off In China | Earth Wise

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The total amount of solar power generating capacity in the world has been growing rapidly.  In 2008, there was a total of only 15 gigawatts installed world-wide.  By 2012, the total was 100 gigawatts.  As of this spring, there is now 1 terawatt – that’s 1,000 gigawatts – of solar power installed in the world.   About a third of that total is in China, and solar power is really booming there.

Estimates are that China will install 108 gigawatts of solar capacity this year, which is about double the amount installed in 2021.  Much of the growth in solar in China is in the form of rooftop solar, as opposed to utility-scale solar farms.

China is aiming to have 50% of new factory rooftops carry solar installations by 2025.   By the end of next year, China’s National Energy Bureau is aiming for solar panels to cover 50% of rooftops on party and government buildings, 40% of schools, hospitals, and other public buildings, 30% of industrial and commercial buildings, and 20% of rural homes.  This new initiative will drive China’s installed solar capacity to impressive levels in the coming years.

After China, the leading installers of solar energy capacity are the European Union, the United States, and Japan. 

These figures are for generating capacity.  What ultimately matters is solar’s share of total electricity consumption.  In China and the EU, solar provides over 6% of the electricity used.  In the US, that figure is about 3.5%.  In Germany and Australia, solar power provides 10% of electricity needs.  All these numbers will continue to go up rapidly as solar installations grow.

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China Sees Rooftop Solar Take Off as New Policies Bolster Growth

Photo, posted June 17, 2022, courtesy of Nguyễn Mỹ Hoa via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Progress On Artificial Photosynthesis | Earth Wise

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Photosynthesis is the process by which plants use the energy from sunlight to turn water and carbon dioxide into biomass and ultimately the foods we and other organisms eat.  Scientists at the University of California Riverside and the University of Delaware have found a way to create food from water and carbon dioxide without using biological photosynthesis and without needing sunlight.

The research, recently published in the journal Nature Food, uses a two-step electrocatalytic process to convert carbon dioxide, electricity, and water into acetate, which is the primary component of vinegar.   Food-producing microorganisms then consume the acetate in order to grow.   Solar panels are used to generate the electricity to power the electrocatalysis.  The result is a hybrid organic-inorganic system that is far more efficient in converting sunlight into food than biological photosynthesis.

The research showed that a wide range of food-producing organisms can be grown in the dark directly on the acetate output of the electrolyzer.  These include green algae, yeast, and the fungal mycelium that produce mushrooms.   Producing algae with this technology is about 4 times more energy efficient than growing it with photosynthesis.  Yeast production is about 18 times more energy efficient than the typical method of cultivating it using sugar extracted from corn.

Artificial photosynthesis has the potential to liberate agriculture from its complete dependence on the sun, opening the door to a wide range of possibilities for growing food under the increasingly difficult conditions imposed by the changing climate.

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Artificial photosynthesis can produce food without sunshine

Photo, posted September 7, 2016, courtesy of Kevin Doncaster via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Progress On Perovskite Solar Cells | Earth Wise

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Perovskites are semiconductors with a specific crystal structure.  Their properties make them well suited for making solar cells.  They can be manufactured at room temperature, using much less energy than it takes to make the silicon-based solar cells widely used today.  As a result, perovskite solar panels would be cheaper and more sustainable to produce.  Manufacturing silicon solar cells takes a lot of energy because silicon is forged at around 3000 degrees Fahrenheit. In addition, perovskites can be made flexible and transparent, making it possible to use them in ways unavailable with silicon solar technology.

But unlike silicon, perovskites are very fragile.  The early solar cells made from perovskites in 2009 and 2012 lasted for only minutes.  Lots of potential, but little practicality.

Recently, Princeton Engineering researchers have developed the first perovskite solar cell with a commercially viable lifetime, which is a major breakthrough.  The team projects that the device can perform above industry standards for about 30 years, which is much more than the 20 years designated as a viability threshold for commercial cells.

The research team has developed an ultra-thin capping layer between two of the layers of a perovskite solar cell.  The layer is just few atoms thick but has been demonstrated to dramatically increase the durability of the device. 

There is great potential for the new solar cell technology.  It has efficiency to compete with silicon cells but can be tuned for specific applications and can be manufactured locally with low energy inputs.  If successfully commercialized, the result will be solar panels that are cheaper, more efficient, and more flexible than what are available today.

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Once seen as fleeting, a new solar tech shines on and on

Photo, posted January 8, 2020, courtesy of David Baillot/UC San Diego Jacobs School of Engineering via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Floating Solar | Earth Wise

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The largest floating solar array in Europe, 12,000 panels sitting on top of the Alqueva Reservoir in Portugal – will come online in July.  Installing floating solar arrays, which are sometimes called “floatovoltaics”, produce renewable energy while shielding significant expanses of water from the sun’s heat.  These dual benefits have led to floatovoltaic projects in multiple countries around the world.

The city of Cohoes, in New York’s Albany County, has proposed an 8,000-panel floating solar array on the city reservoir.  Federal funding of $3 million for the project was obtained by local Congressman Paul Tonko and, in May, utility National Grid donated $750,000 towards the project.  Engineering work will shortly be underway on the 3.2 megawatt grid of solar panels.

The city of Cohoes pumps its drinking water supplies from the Mohawk River into the 10-acre, manmade reservoir.  The surface of the water is the largest undeveloped open space in the city.  Such reservoirs constitute prime sites for solar arrays since the space cannot be used for other purposes.  In addition, covering the water’s surface with the solar panels greatly reduces evaporation and helps to inhibit the growth of algae.

There are currently only 14 floating solar arrays in the U.S. and all of those are privately owned.  The Cohoes municipal array will be the first of its kind.  There are nearly 500 reservoirs in New York State and 24,000 nationwide that could be sites for floating arrays.   Drought-stricken Western reservoirs like Lake Mead and Lake Powell could be ideal locations of solar arrays.  Those reservoirs lose huge amounts of water to evaporation.  There are estimates that floating arrays could provide as much as 10% of the nation’s electrical needs.

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National Grid gives Cohoes $750,000 for floating solar array project

Photo, posted August 25, 2010, courtesy of Martin Abegglen via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Recycling Shingles | Earth Wise

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Every year in the US, about 13 million tons of asphalt material is removed from old roofs to be replaced with new shingles.  Only about 10% of that is recycled for use in paving and various roadway projects.  The other 12 million tons of asphalt ends up in landfills where it takes a very long time to break down.

GAF, the largest roofing manufacturer in North America, has developed a shingle recycling process for which it has received three patents.  The process involves grinding torn-off shingles into a refined material which can then be introduced into the shingle manufacturing process.  The material – referred to as RAS for recycled asphalt shingles – has the potential to significantly reduce the amount of virgin asphalt needed to make new shingles.

Tests by GAF reclaimed upwards of 90% of the waste shingle material and produced new shingles containing up to 15% recycled content.  Underwriters Laboratories certified the shingles containing RAS material with regard to their safety and effectiveness.  The GAF process opens to door to creating a circular, sustainable economy for asphalt used for roofing shingles.

Roofs play an important role in the transition to a green economy.  Apart from recycling asphalt shingles, there are increasing options for solar shingles, which take the place of both traditional asphalt shingles and ordinary solar panels by integrating them into a single roofing product.  There are also so-called green roofs, which replace conventional roofing materials with a contained green space atop a building. Such roofs provide stormwater management, cooling, and an interesting aesthetic.

All aspects of buildings play important roles in our environment – even their roofs.

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5 Ways Roofers Can Celebrate Earth Day, Everyday

Photo, posted April 15, 2012, courtesy of Robert Taylor via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

A Solar-Powered Target Store | Earth Wise

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Many companies have made sustainability commitments of various types. Environmental organizations have urged big-box and grocery stores to install solar panels on their rooftops and parking lots thereby reducing their energy usage and expanding the country’s supply of renewable energy.  These places occupy large areas and therefore are capable of supporting large solar arrays.

According to a report by two environmental advocacy groups, rooftop solar panels on retail stores could generate enough electricity to power the equivalent of nearly 8 million U.S. homes.

Target Stores are one of the retailers that has been making an effort to be a greener company.  Target has installed solar panels on about 25% of its approximately 1,900 stores.  The Target store in Vista, California, about 40 miles north of San Diego, is the company’s most sustainable store.  It already had solar panels on its rooftop, powering a portion of the store.

But now it has installed massive carports topped with solar panels high above its parking lot.  With these panels, this Target can now produce enough renewable energy to power the entire store, from its refrigeration to its heating and air conditioning. Adding in some of the other energy-saving features of the store, Target expects to produce 10% more energy than the store needs, which it will return to the local power grid.  This is Target’s first net-zero energy store.

Target is not the only big retailer going solar.   Home Depot, Lowe’s, and Walmart all have been installing solar panels on some of their rooftops.  Even some restaurants are trying to reach sustainability goals with solar panels.  This is a trend that hopefully will continue to grow.

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Target looks to massive solar panels in a California parking lot as a green model to power its stores

Photo, posted June 30, 2014, courtesy of Mike Mozart via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Community Solar In New York | Earth Wise

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New York has now installed 1 GW of community solar capacity, which is more than any other state.

Community solar is a solar energy project within a geographic area for which the benefits flow to multiple customers such as individuals, businesses, nonprofits, or other groups.  For the most part, the customers benefit from energy being generated by solar panels located at an off-site array.  Customers typically buy or lease a portion of the solar panels in the array and then receive an electric bill credit for the electricity generated by their share of the community solar system.  It is a great option for people who can’t install their own solar panels because they don’t own their home, don’t have a suitable location for various reasons, or have financial constraints.

Community solar in New York now generates enough electricity to power 209,000 homes.  Community solar installations accounted for 70% of New York’s solar additions in 2021 and the state has a pipeline of 708 more projects totaling 2.3 gigawatts.

The NY-Sun program run by NYSERDA since 2011 has directed over $200 million to low-to-moderate income households as part of its Solar Energy Equity Framework. 

Growing community solar depends strongly on policy expansion.  At this point, 19 states and D.C. have established policies and programs to support community solar adoption.  The federal government set a goal of powering 5 million American homes with community solar over the next five years.  With 30% of the country’s current community solar capacity, New York is leading the way.

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New York reaches 1 GW community solar milestone

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

Earth Wise is a production of WAMC Northeast Public Radio.

Solar Canopies | Earth Wise

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

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

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

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

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

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

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

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

Earth Wise is a production of WAMC Northeast Public Radio.

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.

Red Hot Chili Solar Panels | Earth Wise

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The majority of solar panels in use today are made from either single-crystal or polycrystalline silicon, the same stuff used to make the ubiquitous chips in computers, cell phones, and countless other devices.  In addition, a growing fraction of solar panels utilize thin-film technology, which offers cost and flexibility advantages.

Monocrystal silicon still provides the highest efficiency and longest lifespan in commercially available panels, but the lower costs and some other features of thin-film solar panels are growing that market over time.

More recently, perovskite solar cell technology has been a source of great interest in the research community.  Perovskites are a class of minerals with a specific crystalline structure that already have uses in various applications.  As a solar cell material, perovskites offer the potential for converting more sunlight to electricity, being manufactured far more cheaply using no exotic or expensive materials, being more defect-tolerant, as well as a having number of other advantages.  They also have the potential for having very high efficiency. 

Recently, a group of researchers in China and Sweden published results of studies demonstrating that the addition of a novel ingredient has increased the efficiency of perovskite solar cells to nearly 22%, which is better than most commercial silicon solar cells.  The ingredient is capsaicin, the chemical that gives chili peppers their spicy sting.  Adding capsaicin expands the grains that make up the active material of the solar cell, allowing the more effective transport of electricity. 

Why did the researchers think of adding the active ingredient of hot peppers to a solar cell in the first place?  So far, they aren’t saying.

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Solar panels capture more sunlight with capsaicin – the chemical that makes chili peppers spicy

Photo, posted August 16, 2019, courtesy of Pedro via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Community Solar With Storage In New York | Earth Wise

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Community solar allows members of a community to share the benefits of solar power even if they cannot or prefer not to install solar panels on their own property.  There are several models for how community solar works, but all of them allow members to benefit from solar power being generated by an offsite solar array by effectively allocating a portion of its output to them.  In any event, community solar can save money on electric bills and allow people to make use of renewable energy for their needs.

A next step in the evolution of a decentralized energy system is incorporating energy storage into community solar projects.  The first one of these in New York State has now been completed in Yorktown Heights in Westchester County.  The project consists of 557kW of rooftop solar in the form of nearly 1,500 solar panels paired with 490kW of four-hour Tesla Powerpack battery energy storage.  The system is expected to provide 150 participants with approximately 10% savings on their monthly electric bills over 25 years, as well as providing power to 12 Tesla electric vehicle charging stations.

The project was funded by NYSERDA, under its Retail Energy Storage Incentive program, which currently includes 50 community solar-storage paired projects across New York State that are expected to be installed in the next two to three years.

New York has been actively promoting community projects in support of goals announced by Governor Andrew Cuomo to install 6,000MW of solar in the state by 2025 and 3,000MW of energy storage by 2030.

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First community solar-storage project completed in New York

Photo, posted June 21, 2017, courtesy of Franck Michel via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Recycling Solar Panels | Earth Wise

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It is inevitable that the things we make and use eventually outlive their useful lives and become waste that we have to deal with.  Solar panels, despite their impressively long lifetime, can’t escape this general principle.   As pioneering solar panels near the end of their 30-year electronic lives, they could well become the world’s next big wave of e-waste.

According to the International Renewable Energy Agency, nearly 90 million tons of solar panels will have reached their end of life by the year 2050, resulting in about 7 million tons of new solar e-waste per year.

Solar photovoltaic deployment has grown at unprecedented rates in recent years.  The total global installed capacity is about 600 GW today; projections are that there will be 1,600 GW by 2030 and 4,500 GW by 2050.

Solar panels contain valuable materials, including silver and high-purity silicon.  But current recycling procedures are not cost-effective.   Only about 10% of panels are currently recycled in the U.S.   The rest go to landfills or are shipped overseas to become another country’s problem.

Before solar waste becomes a major problem, the industry needs to better address the issue.  Strategies include improving the design of panels to align with recycling capabilities as well as developing new recycling methods that can more efficiently extract and purify the valuable materials in the panels.  Industry researchers are also looking into ways to repair and resell panels that are still in good condition and to repurpose old panels for less demanding functions like e-bike charging stations and housing complexes.

Like most things, solar panels do fail over time and with a rapidly growing number of them in the world, we need to figure out how to avoid them adding to the world’s problems.

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Solar Panels Are Starting to Die. Will We be Able to Recycle the E-Waste?

Photo, posted January 6, 2006, courtesy of Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Small-Scale Climate Solutions | Earth Wise

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In order to meet international climate targets, we need to cut greenhouse gas emissions in half over the next decade and reach net-zero by mid-century.  Achieving this will require unprecedented and rapid changes in how energy is supplied, distributed and used.

Researchers at several European universities collected data on a wide variety of energy technologies at different scales and tested how well they performed in accomplishing an accelerated low-carbon transformation. 

Large-scale, costly, non-divisible or so-called lumpy technologies, such as utility-scale generation, nuclear power, carbon capture and storage, high-speed transportation, and whole-building retrofits are often seen as the most effective way to achieve emission-reduction goals. A key finding of their study is that low-carbon technologies that are smaller scale and can be mass deployed are more likely to enable a faster transition to net-zero emissions.

So-called granular options include solar panels, electricity storage batteries, heat pumps, smart thermostats, electric bikes, and ride-share services.  These options scale not by becoming larger but by replicating.

Small-scale options are quicker to deploy, their technologies have shorter lifespans and are less complex, so innovations and improvements can be brought to market more rapidly.  They are also more widely accessible and help create more jobs, giving governments a sound basis for strengthening climate policies.

However, smaller-scale technologies are not a panacea.  There are no small-scale replacements for industrial plants and other kinds of major infrastructure, but in many different contexts, they can outperform larger-scale alternatives as a means of accelerating the low-carbon transformation.

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Smaller scale solutions needed for rapid progress towards emissions targets

Photo, posted April 8, 2019, courtesy of the City of St Pete via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Solar And Wind Power In China | Earth Wise

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Reducing greenhouse gas emissions is a global challenge and nowhere is that challenge greater than in China.  China accounts for 30% of the world’s emissions and much of that comes from coal power plants.  If the world is going to reach its climate targets, China is going to have to replace as much as possible of its current power mix with renewable energy.

As of 2018, China still made 69% of its electricity from fossil fuels.  Its vast coal reserves have driven its rapid industrialization and better standard of living.  But terrible air pollution problems along with climate issues have led to heavy investments and rapid expansion of both wind and solar power in China.

China is now a world leader in renewable energy, both in terms of producing and using renewable power.  At the start of 2016, China had installed a total of 145,000 megawatts of wind power, which is 3,000 MW more than all 28 European Union countries combined.  And this has occurred even though China only started developing their wind power industry 30 years later than the first EU countries.

Until 2009, China exported almost all the solar panels it produced.  But gradually China began to use solar energy in a big way.  The industry took off in 2014, and growth has been exponential.  Solar power production in China is now almost as extensive as wind power.

One has to consider that much of China’s electricity production is used by industries that produce products for the rest of the world.  In effect, these are exported emissions.  China has a long way to go in replacing its fossil fuel generation and we all have a stake in China succeeding in the task.

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China’s rapid development of solar and wind power

Photo, posted November 12, 2007, courtesy of Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Figuring Out Photosynthesis | Earth Wise

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Plants have been harnessing the sun’s energy for hundreds of millions of years. Algae and photosynthetic bacteria have been doing the same for even longer, all with remarkable efficiency and resiliency. 

People have used the energy of the sun in one way or another for millennia, but only recently have we gotten sophisticated about it by using devices like solar panels and sensors.  And we still have a long way to go to get anywhere close to the efficiency of plants. It’s no wonder, then, that scientists have long sought to understand exactly how photosynthesis works.

Scientists from the U.S. Department of Energy’s (DOE) Argonne National Laboratory, and collaborators at Washington University in St. Louis, recently solved a critical part of the age-old mystery of photosynthesis, studying the initial, ultra-fast events through which photosynthetic proteins capture light and use it to initiate a series of electron transfer reactions.  Electrons in plants have two possible pathways to travel but only use one.   

But as a result of their efforts, the scientists are now closer than ever to being able to design electron transfer systems in which they can send an electron down a pathway of their choosing. 

By gaining the ability to harness the flow of energy, it may be possible to incorporate new design principles in non-biological energy systems. This could allow us to greatly improve the efficiency of many solar-powered devices, potentially making them far smaller. Understanding the intricacies of photosynthesis creates a tremendous opportunity to open up completely new disciplines of light-driven biochemical reactions, perhaps even ones that haven’t been envisioned by nature.

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Scientists unravel mystery of photosynthesis

Photo, posted June 14, 2017, courtesy of Alex Holyoake via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Minerals And Metals For A Low-Carbon Future | Earth Wise

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For the past century, economies and geopolitics have largely been driven by our insatiable appetite for oil and fossil fuels in general.  As we gradually make the transition to a low-carbon energy future, the focus on oil will shift to sustainable supplies of essential minerals and elements.

The use of solar panels, batteries, electric vehicle motors, wind turbines, and fuel cells is growing rapidly around the world.  These technologies make use of cobalt, copper, lithium, cadmium, and various rare earth elements.  The need for any one of these things may diminish if alternatives are found, but there will continue to be a growing reliance on multiple substances whose physical and chemical properties are essential to the function of modern devices and technologies.

In some cases, global supplies of particular minerals and elements are dominated by a particular country, are facing social and environmental conflicts, or face other market issues.  Shortages of any of them could create economic problems and derail progress much as the oil-related energy crises of the past have.

The world faces challenges in managing the demand for low-carbon technology minerals as well as limiting the environmental and public health damage that might be associated with their extraction and processing.  Expanded use of recycling and reuse of rare minerals will be essential.

As the relatively easy sources of these materials become exhausted, other resources will become more attractive.  These include various valuable ecosystems, oceanic deposits, and even space-based reserves.

Ushering in the low-carbon future is not a simple matter and will require responsible actions by the world’s governments and industries. In undoing the damage from the oil age, we must avoid new damage from the low-carbon age.

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Sustainable supply of minerals and metals key to a low-carbon energy future

Photo, posted March 13, 2015, courtesy of Joyce Cory via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

The Largest Community Solar Program

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Community solar projects allow customers to benefit from the economic and environmental attributes of solar energy when they don’t have the ability to invest in their own system for any number of reasons.

Florida Power & Light company is proposing to build the largest community solar program in the United States, pending regulatory review.  The planned installation of 1,490 MW of new solar capacity at 20 new power plants distributed across FPL’s service territory is expected to generate an estimated $249 million in net savings for all FPL customers over the long term.

In addition to becoming the largest community solar program in the country, the new program would also be the largest voluntary low-income solar offering in the country.  Low-income households are typically unable to benefit from solar energy because of not having the means to invest in the technology.  The new SolarTogether program will have more than 35 megawatts of capacity dedicated to low-income Florida families.  Solar energy is a critical tool for enabling low-income families to tap into energy savings. 

The SolarTogether program would provide direct savings in the form of bill credits, making solar an affordable option for any customer.  The Southern Alliance for Clean Energy and Vote Solar joined with FPL to help design the program to include a low-income component and request Florida Public Service Commission approval. There is broad support for the program from universities, county and city governments, and private companies.  In addition, more than 90,000 residential and small business customers have already signed up to receive more information.  The utility hopes to receive regulatory approval in time to launch during the first quarter of 2020.

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FPL plans nation’s largest community solar program; includes low-income focus

Photo, posted March 8, 2018, courtesy of Babcock Ranch via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Pulling Water From The Air

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A couple of years ago, we reported on the early development of a device that harvests water from the air that even works in the low humidity environment of a desert.  Since then, the researchers from UC Berkeley have continued to improve the device and it is now 10 times better than it was two years ago.

The harvester is based on a porous water-absorbing material called a metal-organic framework, or MOF.  The latest version can pull more than five cups of water from low-humidity air per day for every kilogram of the improved MOF material and that is more than enough water to sustain a person.  The harvester cycles around the clock and is powered by solar panels and a battery.

Previous techniques for condensing water from air at low humidity required cooling down the air to temperatures below freezing, which is not economically practical.  The MOF-based device does not require any cooling.

The Berkeley researchers have formed a startup company – Water Harvester, Inc. – which is now testing and will soon market a device the size of a microwave oven that can supply 7 to 10 liters of water per day, which is enough drinking and cooking water for two or three adults.

An even larger version of the harvester, which would be the size of a small refrigerator, would provide 200 to 250 liters of water per day, enough for a household to drink, cook, and shower.  The new company envisions a village-scale harvester that would produce 20,000 liters per day, still running off of solar panels and a battery.

Water Harvester believes the water needs for many people can come out of the thin air.

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Water harvester makes it easy to quench your thirst in the desert

Photo courtesy of Grant Glover (University of South Alabama) via UC Berkeley.

Earth Wise is a production of WAMC Northeast Public Radio.

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