clean

Clean Gas From An Artificial Leaf

November 27, 2019 By EarthWise Leave a Comment

Photosynthesis is the process used by plants, algae and certain bacteria to harness energy from sunlight and turn it into chemical energy. It is often described as the green engine of life on earth.

For quite some time, there have been extensive research efforts around the world in the area of artificial photosynthesis. The goal is to somehow mimic the behavior of plants in order to generate clean-burning fuels using nothing more than sunlight and the carbon dioxide in the air.

Researchers at the University of Cambridge have recently demonstrated a so-called artificial leaf that can directly produce syngas using sunlight. Syngas is a fuel gas mixture consisting primarily of hydrogen and carbon monoxide. Most people haven’t heard of syngas, but many products are created using it. Being able to produce it sustainably would be a critical step to a far greener chemical and fuel industry.

The artificial leaf contains two light absorbers, similar to the molecules in plants that harvest sunlight, which are combined with a catalyst made from the naturally abundant element cobalt. When the device is immersed in water, one light absorber uses the catalyst to produce oxygen. The other carries out the chemical reaction that reduces carbon dioxide and water into carbon monoxide and hydrogen. The result is the syngas mixture.

It turns out that even a rainy or overcast day provides enough light to drive the process.

Previous artificial leaf devices have mostly just produced hydrogen. The Cambridge device produces syngas thanks to the novel combination of materials and catalysts it uses.

The researchers are now focused on finding ways to use the technology to produce a sustainable gasoline substitute.

**********

Web Links

‘Artificial leaf’ successfully produces clean gas

Photo, posted August 15, 2014, courtesy of Mike Mozart via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

The Largest Community Solar Program

November 22, 2019 By EarthWise Leave a Comment

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.

**********

Web Links

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.

Hydrogen From The Ocean

November 15, 2019 By EarthWise Leave a Comment

Hydrogen is frequently touted as an excellent source of clean energy that could be used as a fuel in vehicles, or as a storage medium for energy generated by wind and solar power. The challenge is that hydrogen is rather difficult and expensive to attain, and the most economical methods are not clean and green.

Most industrial hydrogen is produced by reforming natural gas, which has the drawback that carbon dioxide is generated in the process. The environmentally friendly way to produce hydrogen is via electrolysis, in which a chemical reaction is triggered by a catalyst enabling electricity to split water into its constituent elements of oxygen and hydrogen.

The best performing catalyst for electrolysis is platinum, but its high price is a big drawback for the economics of making hydrogen. Researchers at the Pacific Northwest National Laboratory have found a pairing of minerals that may solve the problem. Testing a molybdenum-phosphide catalyst with wastewater in a small reactor called a microbial electrolysis cell revealed that the new catalyst actually worked better than platinum.

Even better, the molybdenum-phosphide catalyst worked well with seawater. If hydrogen can be produced using seawater, there would be a pretty much unlimited resource for making it. By eliminating the use of platinum catalysts, it may be possible to reduce the cost of hydrogen made by electrolysis to a competitive level.

Hydrogen as a vehicle fuel currently costs about twice as much as gasoline on an energy-equivalent basis. Given that running cars from batteries is considerably cheaper than using gas, the cost of hydrogen needs to come down considerably for it to be a viable vehicle fuel.

**********

Web Links

Ditching Platinum for the Ocean Could Make Hydrogen Cheap

Photo, posted July 19, 2011, courtesy of Heather Paul via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

The Benefits Of Zero-Carbon Cities

November 8, 2019 By EarthWise Leave a Comment

A new report issued by a coalition of 50 leading international institutions shows that low carbon initiatives in cities could reduce urban emissions by nearly 90% and support 87 million jobs worldwide by 2030. The report finds that implementing low carbon measures in cities would be worth almost $24 trillion by 2050.

Cities are home to more than half the world’s population but produce 80% of gross domestic product and 75% of carbon emissions. The research highlights the significant benefits carbon reduction can bring to cities in areas such as public health, job creation, and poverty alleviation.

The report shows that it is possible to cut 90% of emissions from cities using currently available technologies and practices including carbon savings from buildings, transportation, materials efficiency, and waste reduction. Doing so would require an investment of nearly $2 trillion per year but would generate annual returns of nearly $3 trillion in 2030 and $7 trillion in 2050 based on cost savings alone. Many low carbon measures would pay for themselves in less than five years, including more efficient lighting, electric vehicles, improved freight logistics, and solid waste management.

In addition to economic benefits, compact, connected and clean cities could provide a higher standard of living and greater opportunity for all. These measures would also reduce air pollution, cut chronic traffic congestion, and improve worker productivity.

The report offers case studies from around the world where national and local governments have worked together to rapidly and profoundly transform their cities for the better within 20 or 30 years.

**********

Web Links

The benefits of investing in zero-carbon cities

Photo, posted September 8, 2018, courtesy of Steffen Flor via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Falling U.S. Carbon Emissions

September 16, 2019 By EarthWise Leave a Comment

Reducing carbon emissions is a goal embraced by nearly every country in the world, but actually accomplishing it isn’t easy. It is true that renewable energy sources are playing a growing role in energy systems, but counterbalancing that trend is growing energy demand, especially in developing countries.

Here in the US, energy-related CO2 emissions actually went up nearly 3% in 2018 compared with 2017. But the US Energy Information Administration is now forecasting a 2% drop in emissions this year.

The main reason energy-related emissions are headed lower at this point is coal-fired power plant retirements. More than 90% of the coal used in the US goes toward electric power and utilities are increasingly turning away from coal.

The rapid shift away from coal has mostly been due to the increasing use of natural gas. Natural gas is not actually a clean and green fuel, but it is definitely less carbon-intensive than coal. Overall, the total installed capacity of renewable sources – hydropower, wind, solar, geothermal, and biomass – has now actually surpassed the capacity of coal plants. Given that renewables have in many places become the cheapest power option, there is little chance that coal has much of a future, despite efforts by the current administration.

The electric power sector is gradually moving away from all carbon-emitting sources – a trend that is being reinforced by legislation in many states. The real CO2 emissions leader is petroleum, which accounts for nearly half of the total. We have a long way to go to reduce emissions from the use of petroleum. There are over 250 million cars and trucks on US roads and only a little over a million of them don’t burn fossil fuels.

**********

Web Links

Photo, posted November 6, 2017, courtesy of Cindy Shebley via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

A Solar-Powered Airport

August 12, 2019 By EarthWise 1 Comment

The Chattanooga Metropolitan Airport in Tennessee has become the first airport in the United States to run entirely on solar power. The small airport operates over 60,000 flights a year and has recently completed work on a 12-acre, 2.64-megawatt solar farm that generates enough clean electricity to account for the airport’s total energy needs.

The project was funded largely by the Federal Aviation Administration, cost $10 million, and took nine years to complete. The facility uses onsite batteries to help power operations at night. The installation is expected to last 30 to 40 years.

The solar farm is in the southwest corner of the airfield on land that is unusable for aviation purposes. It is visible from the two runways at the airport.

Officials from nearly 50 airports around the world have visited or contacted the Chattanooga airfield in recent years to learn about its solar operations. Several major airports, including San Diego and London’s Gatwick, have also installed solar panels that provide a portion of their power needs. The world’s busiest airport – Atlanta’s Hartsfield-Jackson – is looking into constructing renewable energy microgrids to power part of its operations. Airports generally have plenty of vacant land that can be used for solar panels that can lower their power bills.

The largest airport solar installation is actually Cochin International in Kerala, India, which became 100% solar powered in 2015. It is the 7^th largest airport in India. Its solar array has nearly 30 megawatts of capacity. Airport managers there were fed up with huge electric bills and invested about $9 million to install the solar array. It is expected to have paid for itself in the next couple of years.

**********

Web Links

Chattanooga Becomes First U.S. Airport to Run Entirely On Solar

Photo courtesy of Chattanooga Metropolitan Airport.

Earth Wise is a production of WAMC Northeast Public Radio.

Fishers Helping To Clean The Oceans

August 2, 2019 By EarthWise Leave a Comment

Marine litter – particularly plastics – is a global, persistent, and increasing threat to the oceans. Much of it comes from discarded materials on shore that makes their way to the sea but waste from the fishing industry is a also a major contributor to the problem.

Commercial fishers are acutely aware of the potential for marine litter to damage and even destroy their livelihoods and are starting to try to be part of the solution instead of just part of the problem.

An initiative called Fishing for Litter, which has been operating around the British coastline since 2006, is an example.

With hubs in Scotland and South West of England, FFL aims to reduce the amount of marine litter in the sea by physically removing it while also highlighting the importance of good waste management in the fishing fleet. Fishers have to assume responsibility for their own waste and dispose of it in a responsible manner. They also have a unique ability to access remote and hard to reach marine litter caused by others.

A survey of 120 commercial fishers revealed that they often found marine litter in their hauls and that keeping the sea and coasts clean was important to them.

The responsibility for reducing marine litter does not belong to any single industry or organization. It requires a collective global change of behavior. The problem directly affects fishers, so they are especially motivated to do something about it. They can make an important contribution to an issue that ultimately affects us all. Groups like Fishing for Litter are providing a model for behavior that we can only hope that others around the world can emulate.

**********

Web Links

Fishers keen to help address the problem of marine litter

Photo, posted July 9, 2009, courtesy of Rennett Stowe via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Capital Region Community Solar

July 19, 2019 By EarthWise Leave a Comment

New York’s Capital Region is getting a major new community solar farm. A community solar farm is a solar power installation whose output is shared by multiple community subscribers who receive credit on their electricity bills for their share of the power produced. The primary purpose of community solar is to allow members of a community to have the benefits of solar power even if they cannot or prefer not to install solar panels on their own property.

US Light Energy has broken ground on the Sugar Hill Solar Farm, to be located on 40 acres of land on the Sugar-Hill/Sugar-View Farm in Clifton Park. The 7-megawatt, ground-mounted solar project will include nearly 20,000 solar modules. When fully operational later this year, the facility is expected to produce more than 8.6 million kilowatt-hours of energy a year.

The farm will be part of New York state’s Community Solar Program, and the electricity it generates can be supplied to customers anywhere in National Grid’s existing distribution system. Residential and commercial properties in Clifton Park will have 30 days to subscribe before the solar energy generated by the farm is opened to the general public. Subscribers of community solar farms typically save 10% on their electricity bills.

There are already community solar programs in operation in several Capital Region communities, but this is the first one in the Clifton Park Area. Apart from providing savings on utility bills, community solar allows consumers to support clean, locally generated power with little or no upfront costs. Not everyone is in a position to put solar panels on their roof, but community solar is increasingly an option for New York residents.

**********

Web Links

Construction begins on 7-MW community solar farm in New York

Photo, posted March 19, 2012, courtesy of Kate Ausburn via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Making Roads From Ocean Plastic

June 7, 2019 By EarthWise Leave a Comment

Like many other places around the world, India has a big problem with plastic waste. Its 1.3 billion people each use an average of 24 pounds of plastic per year and much of it ends up in the Arabian Sea and Indian Ocean.

Fishermen in India’s southern state of Kerala have taken on the battle against plastic waste in the ocean by launching a campaign called Suchitwa Sagaram, or Clean Sea, in which they are collecting the plastic and bringing it back to shore.

In the first 10 months of the program, fisherman have removed 25 tons of plastic from the Arabian Sea. Once the plastic waste reaches shore, it is fed into a plastic shredding machine. As is the case for many of India’s plastic recycling schemes, the shredded plastic from the sea is converted into material that is used for road surfacing.

There are more than 20,000 miles of plastic roads in India, mostly in rural areas. In fact, more than half the roads in the southern state of Tamil Nadu are plastic. Such roads have become popular because they are more resilient to India’s searing heat. The melting point of plastic roads is around 150 degrees Fahrenheit as compared to 122 degrees for conventional roads.

Roads made from recycled plastic are also cheaper than ones using conventional plastic additives. A mile of plastic road uses the equivalent of a million and a half plastic bags and saves about a ton and a half of asphalt. Overall, plastic roads are about 8% cheaper than conventional roads and create jobs for people in the fishing communities.

India’s plastic roads are a promising way to fight the problem of ocean plastic pollution.

**********

Web Links

These Indian fishermen take plastic out of the sea and use it to build roads

Photo, posted April 25, 2016, courtesy of Bo Eide via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

From Coal Plant To Solar Farm

June 5, 2019 By EarthWise Leave a Comment

The Nanticoke Generating Station in Ontario, Canada was the largest coal-fired power plant in North America. It was commissioned in 1972 and was capable of providing nearly 4,000 megawatts of electrical power into the southern Ontario power grid. At peak, the plant consumed nearly 40,000 tons of coal per day.

The government of Ontario eventually decided to phase out all of its coal plants about ten years ago but the decommissioning was delayed for a time because of the lack of replacement sources of energy. The plant began to shut down its individual generating units starting in 2010. By the end of 2013, the Nanticoke plant was shut down for good.

In 2016, a 44 MW solar power station was contracted for the site and construction began last year. The plant opened at the beginning of April coinciding with the one-year anniversary of the demolition of Nanticoke’s smokestacks, which once stood 650 feet tall.

The new solar farm has 192,431 solar panels spread across 260 acres. The facility, situated on the shores of Lake Erie in Ontario, will generate enough electricity to power more than 7,200 homes.

The idea to use part of the retired coal plant’s property for a new solar farm was spearheaded and paid for by Ontario Power Generation, the Six Nations of the Grand River Development Corporation, and the Mississaugas of the Credit First Nation.

The Chief of the Mississaugas called the solar project an important economic development in the region and for tribal nations that sets the stage for future mutually-beneficial partnerships between Ontario Power Generation and others.

**********

Web Links

Canadian Coal-Fired Power Plant Transformed into Solar Farm

Photo, posted July 26, 2009, courtesy of Jason Paris via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Hydrogen From Water And Sun

March 7, 2019 By EarthWise 1 Comment

There are research efforts around the world seeking ways to produce hydrogen starting from water and using clean energy. Finding an economical and scalable way to do this is a key to the so-called hydrogen economy.

A recent study at Argonne National Laboratory makes use of a chemical reaction pathway central to plant biology to create a process that converts water into hydrogen using energy from the sun.

The process combines two membrane-bound protein complexes to perform the conversion of water molecules into hydrogen and oxygen.

The first protein complex, which the researchers call Photosystem I, is a membrane protein that uses energy from light to feed electrons to an inorganic catalyst that makes hydrogen. But this represents only half of the overall process.

A second protein complex that they call Photosystem II uses energy from light to split water and take electrons from it. The electrons are then fed to Photosystem I.

The two protein complexes are embedded in thylakoid membranes, which are like those found inside the oxygen-creating chloroplasts in plants. This membrane is an essential part of pairing the two photosystems. It supports both of the photosystems and provides a pathway for transferring electrons between the proteins.

The researchers also make use of a synthetic catalyst made from nickel or cobalt that replaces expensive platinum catalysts used in conventional water-splitting schemes. Combining the light-triggered transport of electrons with the synthetic catalyst results in what the researchers call the “Z-scheme”, an adaptation of photosynthesis to produce hydrogen.

The next step is to incorporate the scheme into a living system which the researchers hope will lead to a practical system for hydrogen production.

**********

Web Links

Discovery adapts natural membrane to make hydrogen fuel from water

Photo, posted December 25, 2017, courtesy of Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

A Quiet Clean Energy Revolution

March 5, 2019 By EarthWise Leave a Comment

While the Trump administration seeks to prop up and promote use of fossil fuels, the country continues to move in the opposite direction. Last year was actually a pretty positive year for clean energy in the U.S.

In terms of public opinion, 70% of Americans surveyed believe the country should produce 100% of its electricity from renewable energy sources and more than half of survey respondents think renewables are a good idea even if they raise energy bills.

Companies in the U.S. purchased a record 6.43 gigawatts of renewable power, enough to power 1.5 million homes. The number of corporations entering into renewable energy deals doubled last year.

More than 300 U.S. cities, towns or counties have made commitments to climate action and, as of November, 99 cities have committed to 100% renewable energy, doubling the total from a year ago.

A number of gubernatorial candidates running on ambitious renewable energy platforms were elected in November including those in Illinois, Colorado, New Mexico, Maine and Nevada.

Utilities are responding to the growing demand for clean energy. Consumers Energy in Michigan plans to cut carbon emissions by 80% and stop using coal. Iowa-based MidAmerican Energy will become the first U.S. utility to source 100% of its electricity from renewable sources next year. Xcel Energy, one of the biggest utilities in the country, has committed to be 80% carbon-free by 2030 and go completely carbon-free by 2050.

The fossil fuel industry with its supporters in high places is still kicking and screaming, but there is no doubt that the U.S. energy system is changing, and the quiet clean energy revolution will only pick up more steam in 2019.

**********

Web Links

The US Underwent a Quiet Clean Energy Revolution Last Year

Photo, posted August 15, 2009, courtesy of Ken via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Droughts And Hydropower

February 7, 2019 By EarthWise Leave a Comment

Recent droughts in several western states have led to well-publicized problems including wildfires, loss of trees, and damage to crops. A lesser-known impact of drought conditions has been increases in emissions of carbon dioxide and harmful air pollutants from power generation.

When hydropower runs low in a drought, western states tend to ramp up power generation – and therefore emissions – from fossil fuels. According to a new study from Stanford University, droughts caused about 10 percent of the average annual carbon dioxide emissions from power generation in California, Idaho, Oregon and Washington between 2001 and 2015.

Water is used in electricity generation both directly for hydroelectric power and indirectly for cooling in thermoelectric power plants. When water for hydropower comes up short because of drought conditions, natural gas or coal-fired power plants are brought online to pick up the slack.

These drought-induced shifts in energy sources led to an estimated 100 million tons of carbon dioxide across 11 western states between 2001 and 2015. That is the equivalent of adding 1.4 million vehicles to the region’s roadways. California, whose legislature has mandated that the state be carbon-free by 2045, contributed about half of this total. Washington, which is considering a similar mandate, contributed nearly a quarter of the total.

Western states in recent years have suffered intense droughts that scientists expect to become more common as global warming continues to intensify. The new study indicates that in regions where clean, reliable hydropower has been an important part of the energy mix, it will be increasingly necessary to provide clean backup energy sources in order to meet emission reduction targets.

**********

Web Links

Droughts boost emissions as hydropower dries up

Photo, posted March 7, 2016, courtesy of Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Collecting Clean Water From The Air

February 6, 2019 By EarthWise Leave a Comment

Clean water is an essential requirement for human life and there are many places where it is a scarce commodity. In the world’s deserts, getting water to people requires feats of engineering and irrigation that can be cumbersome and expensive.

Researchers at Ohio State University have produced a couple of new studies that explore options for gathering water from fog and condensation that are based on principles of biomimicry: copying strategies already in use by plants and animals.

The researchers looked at how cactus, beetles and desert grasses all collect water condensed from nighttime fog, gathering droplets from the air and filtering them to roots or reservoirs.

The cactus they studied collects water on its barbed tips before guiding droplets down conical spines to the base of the plant. They learned that conical shapes gather more water than do cylindrical shapes. This is because of a physics phenomenon called the Laplace pressure gradient.

The beetles they studied collect drops of water on waxy, water-repellent bumps on their backs. The water then slides towards the beetle’s mouth on the flat surface between the bumps. Based on this, the researchers experimented with structures that include multiple hydrophilic cones with spaces in between where water droplets can coalesce.

From grasses, they learned that grooved surfaces move water more quickly than ungrooved surfaces – in fact, about twice as much.

The work so far has been on a laboratory-level, but the researchers envision scaling up to structures in the desert that can gather water from fog or condensation and supplement public systems or wells either on a house-by-house basis or on a community-wide basis. Copying cacti, beetles and grasses could supply clean water to people in the desert.

**********