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Is U.S. Offshore Wind Finally Happening? | Earth Wise

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Offshore wind capacity has been growing rapidly in recent years, especially in Europe and China.  Globally, there is now more than 30 GW of offshore wind and industry experts predict that there will be well over 200 GW of installed capacity by 2030.

Meanwhile, the U.S. has only two small pilot projects, one with five turbines off Rhode Island and another with two turbines off Virginia.  But after many years of battles with determined opponents, false starts, regulatory struggles, and other hurdles, the U.S. offshore wind industry appears to be poised to take off.

A combination of significant commitments by power companies to purchase offshore wind power, strong support by the Biden administration, and billions of dollars in investments is creating the new-found momentum.

New York, New Jersey, Virginia, Massachusetts, Connecticut, Rhode Island, and Maryland have collectively committed to buying 30 GW of offshore electricity by 2035.  (That’s enough to power roughly 20 million homes).

Among the first major offshore installations to be completed in the next few years in the U.S. will be Vineyard Wind, 15 miles off of Martha’s Vineyard, another wind farm 60 miles east of New York’s Montauk Point, a third fifteen miles off Atlantic City, New Jersey, and a fourth off the Virginia Coast.

Offshore wind projects will create nearly 40,000 jobs just in the New York-New Jersey area over the next ten years.  There is still some opposition from elements of the commercial fishing industry and from some coastal residents.  However, with state and federal governments committed to reducing carbon emissions and rapidly reducing regulatory barriers, and with the price of offshore wind continuing to get lower and lower, most observers agree that the U.S. offshore wind industry is finally on the verge of really getting going.

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On U.S. East Coast, Has Offshore Wind’s Moment Finally Arrived?

Photo, posted August 9, 2016, courtesy of Lars Plougmann via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

New Records For U.S. Wind Power | Earth Wise

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Wind-powered electricity has been increasing its contribution to the American energy mix for years as the number of installed turbines has rapidly grown.  In the final months of 2020, wind power set a number of new records.  Strong wind conditions in November and December, especially in the central states, led to record output from wind turbines.

On April 10, 2019, the U.S. set a record for daily electricity generation from wind turbines in the lower 48 states by producing 1.42 million megawatthours.  That record stood until several different days during November and December.  The newest record was set on December 23 when wind generation reached 1.76 million MWh.  That constituted 17% of total electricity generation in the U.S.   For the entire year of 2020, wind power accounted for 9% of U.S. electricity generation.

Late 2020 also saw new records set for hourly dispatch of wind resources.  On December 22, between 9 and 10 pm Eastern Time, 82 gigawatts of electricity sourced from wind power was dispatched across the U.S., breaking the one-month-old previous record of 73.4 GW.  Wind power varies considerably over the course of a day.  During December, wind power across the country varied between that record of 82 GW to a low of 14.6 GW.

The contributions from wind power are expected to continue to grow.  The U.S. currently has over 112 GW of installed wind capacity.  Project developers and grid operators plan to add another 12.2 GW of new wind capacity to the U.S. grid by the end of 2021.  More than half of that new capacity will be in Texas and Oklahoma.

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U.S. wind generation sets new daily and hourly records at end of 2020

Photo, posted July 12, 2010, courtesy of Tom Shockey via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Solar Energy And Agriculture | Earth Wise

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According to a new study by Oregon State University researchers, co-developing land for both solar voltaic power and agriculture could provide 20% of total electricity generation in the United States with an investment of less than 1% of the annual U.S. budget.

The concept is known as agrivoltaics – using the same land for both growing crops and generating solar energy.  The proponents of agrivoltaics say that it provides more food, more energy, lower water demand, lower carbon emissions, and more prosperous rural communities.

According to the study, wide-scale installation of agrivoltaic systems could lead to an annual reduction of 330,000 tons of carbon dioxide emission in the U.S. – the equivalent of taking 75,000 cars off the road – and the creation of more than 100,000 jobs in rural communities.  All of this could be achieved with minimal effects on crop yields.

The study finds that an area about the size of Maryland would be needed for agrivoltaics to produce 20% of U.S. electricity generation.  That area of 13,000 square miles constitutes about 1% of current U.S. farmland.

The cost of the solar installations would be $1.1 trillion over 35 years and they would pay for themselves from the electricity generated within 17 years.  Installing the arrays would create the equivalent of 117,000 jobs lasting 20 years.

The researchers are going to install a fully functional solar farm on 5 acres of university owned land to demonstrate to the agricultural community and potential future funders how the study’s findings can be applied in real world agricultural systems.

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Combining solar energy and agriculture to mitigate climate change, assist rural communities

Photo, posted October 11, 2011, courtesy of Michael Coghlan via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

The Path To Net Zero | Earth Wise

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Reaching net zero emissions is both feasible and affordable, according to researchers at the Department of Energy’s Lawrence Berkeley National Laboratory, the University of San Francisco, and consulting firm Evolved Energy Research.   The researchers created a detailed model of the entire U.S. energy and industrial system to produce the first detailed, peer-reviewed study of how to achieve carbon neutrality by 2050.

The study analyzed multiple feasible technology pathways based on very different assumptions of remaining fossil fuel use, land use, consumer adoption, nuclear energy, and biofuel use.  What they had in common was increasing energy efficiency, transitioning to electric technologies, utilizing clean electricity (especially wind and solar power), and deploying small amounts of carbon capture technology.

The decarbonization of the U.S. energy system is an infrastructure transformation.  Getting to net zero by 2050 means adding many gigawatts of wind and solar power plants, new transmission lines, a fleet of electric cars and light trucks, millions of heat pumps to replace conventional furnaces and water heaters, and more energy-efficient buildings.

The various pathways studied have net costs between 0.2% and 1.2% of GDP, which is as little as $1 per person per day.  The cost variations come from various tradeoffs such as the amount of land given to solar and wind farms as well as the amount of new transmission infrastructure required. 

A key result of the study is that the actions required over the next 10 years are similar among all the pathways.   We need to increase the use of renewable energy and make sure that all new infrastructure, such as cars and buildings are low carbon.

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Getting to Net Zero – and Even Net Negative – is Surprisingly Feasible, and Affordable

Photo, posted July 12, 2010, courtesy of Tom Shockey via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Understanding How To Enhance Desalination | Earth Wise

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Desalination is the process of removing mineral components – notably salt – from saline water, generally seawater.  Over 16,000 desalination plants operate across 177 countries, generating 25 billion gallons of fresh water each year.  Currently, desalination accounts for about 1% of the world’s drinking water.

The leading process for desalination in terms of installed capacity as well as new installations is reverse osmosis that makes use of a thin-film composite membrane based on ultra-thin polyamide.

Despite the fact that these membranes are widely used for desalination, they are actually rather poorly understood.  It has not been known exactly how water moves through them.  As a result, much of the progress made on the technology over the decades has been essentially based on guesswork.

A team of researchers at the University of Texas, Austin has used advanced microscopy techniques to solve some of the mysteries of reverse osmosis membranes.  By mapping membranes at very high resolution – less than half the diameter of a DNA strand – they gained a much better understanding of what makes a membrane better at reverse osmosis.

They found that desalination membranes are inconsistent in mass distribution and density and that these inconsistencies can impair membrane performance.  It turns out that inconsistencies and dead zones in membranes play a bigger role than membrane thickness.  By making the membranes more uniform in density at the nanoscale, they were able to increase desalination efficiency 30 to 40 percent, therefore cleaning more water with less energy and at lower cost.

Producing fresh water is not just essential for public health, it is also crucial for use in agriculture and energy production.

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Nanoscale control of internal inhomogeneity enhances water transport in desalination membranes

Photo, posted February 13, 2017, courtesy of Jacob Vanderheyden via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

A New Fishway Technology | Earth Wise

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Freshwater fish populations have declined by more than 80% over the past forty years across the globe.  This is in part due to hundreds of thousands of dams, weirs, and barriers stopping their movements.  These river barriers have disrupted fish reproduction cycles the world over by preventing river fish from migrating to spawn.

Fishways or fish ladders are waterways constructed on or around obstructions in order to provide passageways for fish and other aquatic species.  Often, they consist of a series of small overflow weirs and pools constructed in the form of steps.  Fish need to jump from one pool to another to migrate to the upstream.  Such fish ladders require a large space to construct.  These and several other types of fishways tend to be expensive to install and maintain and are not always successful in allowing fish to get to where they need to go.

Researchers at the University of New South Wales in Australia have come up with an ingenious new type of fishway.  Called a “tube fishway”, it is a low-cost and low-energy installation that works by pumping fish at high velocity – protected by a cushion of bubbly water – through a tube running over the obstructing barrier to deliver them safely into the water on the other side.

They successfully demonstrated a prototype system on a rugged slope behind a campus building that transported fish from one tank to another about 25 feet up the slope.

Fish are attracted into the chamber by suitable geometry and the system uses the energy available from the upper reservoir to lift the fish.  Modeling shows that the system will work for pipes as large as three feet in diameter and could lift fish more than 300 feet vertically. 

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New fishway technology to get fish up and over those dam walls

Photo, posted October 19, 2019, courtesy of Andrew Harvey via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Grid-Scale Battery Storage is on the Rise | Earth Wise

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Driven by steeply falling prices and improving technology, grid-scale battery storage systems are seeing record growth in the U.S. and around the world. Battery storage is a way to overcome one of the biggest obstacles to renewable energy:  the cycling between oversupply when the sun shines or the wind blows, and shortage when the sun sets or the wind drops.  Storing excess energy in battery banks can smooth imbalances between supply and demand.

In California, a 300-megawatt lithium-ion battery plant is being readied for operation with another 100 megawatts to come online in 2021.  The system will be able to power roughly 300,000 California homes for four-hour periods when energy demand outstrips supply.  It will be the world’s largest battery system for a while until even larger systems in Florida and in Saudi Arabia come online.

Nationwide, a record 1.2 gigawatts of storage were installed last year and that number is projected to jump dramatically over the next five years to nearly 7.5 gigawatts in 2025.

The price tag for utility-scale battery storage in the U.S. has plummeted, dropping nearly 70% just between 2015 and 2018.  Prices are expected to drop by a further 45% over the next decade.  Battery performance has continued to improve dramatically with increased power capacity and the ability to store and discharge energy over ever-longer periods of time. 

Favorable energy policies including renewable energy mandates coupled with continued price drops will drive the widespread expansion of battery energy storage.

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In Boost for Renewables, Grid-Scale Battery Storage Is on the Rise

Photo, posted November 17, 2016, courtesy of Steve Ryan via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Shifting Climate Attitudes – Even In Texas | Earth Wise

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Any conversation about climate policy and energy in the United States has to take Texas into consideration.  Texas leads the nation in energy production, providing more than one-fifth of U.S. domestically produced energy.  Texas also uses more energy than any other state and accounts for almost one-seventh of total U.S. energy consumption.  The state’s industrial sector, which includes petroleum refining and chemical manufacturing, accounts for almost half of Texas energy consumption.

As a result, longstanding skepticism among Texans toward the climate movement has represented a real impediment in developing and implementing effective climate policy in this country.  But according to new research at the University of Houston, attitudes in Texas have changed and now mirror those in the rest of the United States.

About 80% of Americans believe that climate change is happening, and now about 81% of Texans hold the same view.  Two out of three Americans are worried about climate change; more than 60% of Texans agree.

Nationwide, 55% agree that the oil and gas industries have deliberately misled people on climate change; 49% of Texans agree. 64% of Americans say hydraulic fracking has a negative effect on the environment and 61% of Texans agree.  People everywhere are willing to pay more for carbon-neutral energy, and a higher premium for gasoline as well.

Mitigation strategies for climate change are not well understood.  While 61% nationwide have heard of carbon taxes, less than half are familiar with carbon management, and only a third have heard of carbon pricing.

As the U.S. heads toward reengaging in efforts to address climate change, Texans appear to have caught up with the rest of the nation.

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Attitudes About Climate Change Are Shifting, Even in Texas

Photo, posted October 1, 2011, courtesy of Steve Rainwater via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

New York And Renewables | Earth Wise

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In 2019, New York generated more electricity from renewable sources than all but three other states.  The 39.4 million MWh of renewable electricity generated in New York was the largest of any state east of the Mississippi. 

New York has been a leader in renewable power long before it became a topic of great interest because of its hydroelectric power.  In 2019, 78% of the state’s renewable electricity came from hydropower.  The Robert Moses Niagara hydroelectric plant is the second-largest capacity conventional hydroelectric power plant in the country. 

The three states that generated more renewable electricity than New York are California, Texas, and Washington.  Washington gets 69% of all its electricity generation from its multiple hydroelectric plants which together produce a quarter of all hydroelectric power in the nation.  Texas leads the nation in wind-powered generation and gets over 17% of its in-state generation from wind.  California gets 14% of its power from solar generation, 7% from wind, and over 16% from its own hydroelectric resources.

Wind is the second-largest source of renewable power in New York, accounting for 11% of renewable generation in the state and 3% of total electricity generation.  Solar power is expanding in New York, but the great majority of it is still in the form of small-scale installations on residential and commercial rooftops.

New York’s renewable generation grew from 19% in 2005 to 30% at present.  New York’s Clean Energy Standard adopted in 2015 requires the state to generate 100% carbon-free electricity by 2040.

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New York generated fourth most electricity from renewables of any state in 2019

Photo, posted October 15, 2010, courtesy of michael-swan via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Why Do Trees Change Color? | Earth Wise

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We had a particularly colorful fall in the Northeast this year.  Almost everywhere you looked, there were brilliant displays of yellow, orange, and red.  The colors of fall are a result of chemistry and environmental events that may have taken place many months in the past.

The color of leaves comes from 4 pigments whose effects are governed by photosynthesis.  The one that is actually used in photosynthesis is chlorophyll and it causes leaves to be green.  But when a tree begins to prepare for dormancy, it stops producing chlorophyll, the green pigmentation fades, and the other pigments that were already in the leaves become visible.

There are xanthoplylls, which are the yellow pigments that are seen the most in fall trees.  They are the same pigments that color egg yolks and sometimes parts of the human eye.  They are only produced by plants and appear in humans and animals only through consumption.

There are carotenes, which are the orange pigments found in fruits and vegetables, such as carrots, oranges, some bell peppers and squashes.

And there is anthocyanin, which is the pigment found in blueberries, blackberries, and red or violet roses.  Its color depends on the pH level of the plant; higher pH leads to darker color.  This is the pigment seen in red maples, black cherry trees, Shumard oaks, and more.  Only 10% of trees in temperate climates produce anthocyanin and its red pigmentation and most of those trees are in New England.

All these pigments serve purposes.  They help trees absorb light energy, prevent sun damage, and even regulate how much energy chlorophyll produces.

There are complicated chemical and environmental factors at play in fall foliage but when they come together like they did this year, it’s a magnificent spectacle.

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Why Do Trees Change Color?

Photo, posted October 17, 2020, courtesy of John Brighenti via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

The Toughest Beetle Of Them All | Earth Wise

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In 2015, UC Riverside materials scientists placed a mottled black beetle in a parking lot and ran it over with a Toyota Camry.  Twice.  Crushed beneath the wheels of a 3,500-pound sedan, the inch-long insect made it through without a scratch.

For the past five years, a group of scientists have been studying this remarkable bug, which has the splendid name of the diabolical ironclad beetle. Using a combination of advanced microscopy, mechanical testing, and computer simulations, the researchers have figured out the secret of this beetle’s crush resistance.

The beetle’s super-toughness lies in two armorlike structures called elytra that meet in a line, called a suture, running the length of the abdomen.  The suture acts like a jigsaw puzzle.  It connects various exoskeletal blades – the puzzle pieces – in the abdomen under the elytra.   These structural components can act in different ways.  The interconnecting blades lock to prevent themselves from pulling out of the suture.  The suture and blades delaminate, leading to a graceful deformation rather than catastrophic failure.  These strategies dissipate energy to circumvent fracturing.

The researchers found that the diabolical ironclad beetle – just had to say that name again – can take on an applied force of about 150 newtons, a load at least 39,000 times its body weight.  (That’s the equivalent of a 150-pound person resisting the crush of about 25 blue whales).

An ongoing challenge for structural engineering is how to join together different materials without limiting their ability to support loads.  The strategies evolved in these beetles may be applicable in gas turbines of aircraft, for example, where metals and composite materials are joined together with mechanical fasteners.   We can learn things from the toughest beetle of them all.

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Diabolical ironclad beetles inspire tougher joints for engineering applications

Photo, posted April 9, 2017, courtesy of Vahe Martirosyan via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Hydropower And Floating Solar | Earth Wise

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According to a new analysis by the National Renewable Energy Laboratory, hybrid systems of floating solar panels and hydroelectric plants have the potential to produce a significant portion of the world’s electricity.

According to their estimates, adding floating solar panels to bodies of water that host hydropower stations could produce up to 7.6 terawatts of power a year from the solar systems, resulting in about 10,600 terawatt-hours of energy.  The total global electricity consumption in 2018 was 22,300 terawatt-hours.  So, the potential in terms of the global appetite for electricity is very large.

This estimate is certainly optimistic.  It does not take into account economic feasibility or specific market demand.  What it does represent is an estimate of the technical and performance potential of floating photovoltaics at hydroelectric facilities.

Floating solar is just starting to be used in the U.S., but it has already caught on overseas where space for ground-mounted systems is at a greater premium. 

According to the NREL study, nearly 400,000 freshwater hydropower reservoirs across the globe could host floating PV sites that could be used in conjunction with the existing hydroelectric plants.  One important advantage of this approach is that the hybrid system would reduce transmission costs by linking to a common substation.  In addition, the two technologies could balance each other, with solar power taking up the slack in dry seasons and hydropower working well in rainy seasons.  In some places, pumped storage hydropower could be used to store excess solar generation.

There is great potential in hybrid floating solar/hydroelectric power.

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Untapped potential exists for blending hydropower, floating solar panels

Photo, posted April 12, 2009, courtesy of Alexis Nyal via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Using CO2 To Convert Seawater Into Drinking Water | Earth Wise

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A chemist at the University of Copenhagen has invented a technology that uses carbon dioxide to convert seawater into drinking water within minutes.  This desalination technology has the potential to replace electricity with CO2 and be used in survival gear and in large-scale industrial plants in places where people don’t have clean drinking water.

Over 800 million people worldwide lack access to clean drinking water and that number is growing rapidly.  Seawater is a vital source of drinking water in many parts of the world, but desalination faces the major challenge of being highly energy intensive.  Desalination plants use huge amounts of fossil fuel-generated electricity and therefore contribute to climate change.

The Copenhagen technology is reminiscent of a SodaStream machine.  Carbon dioxide is added to water, initiating a chemical reaction.  But instead of using it for bubbly carbonation, it is used to separate salt from water.  It works by adding a chemical called CO2-responsive diamine to saltwater.  The diamine compound binds with the added CO2 and acts as a sponge to absorb the salt, which can then be separated.  The entire process takes one to ten minutes.  Once the CO2 is removed, the salt is released again, allowing the diamine to be reused for several more rounds of desalination.

In the laboratory, the method removed 99.6% of the salt in seawater.  The technology is still being developed to lower its price and optimize the recycling process.  It is also being tested on a small scale in the form of water bottles fitted with special filters that can be used in lifeboats or in other outdoor settings.  Ultimately, it could be used to greatly reduce the energy consumption of desalination plants.

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Chemist uses CO2 to convert seawater into drinking water

Photo, posted January 10, 2015, courtesy of Daniel Orth via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Upstate Energy Storage | Earth Wise

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In August, the New York Power Authority announced the start of construction on one of the largest battery energy storage projects in the nation.  Located in Franklin County at the very top of New York State, the project will comprise 20 MW of lithium ion battery storage that will help the state meet its peak power needs by absorbing excess generation that can be discharged later when the grid demands it.

The Northern New York region gets more than 80% of its electricity supply from renewable sources, including the St. Lawrence hydropower project and more than 650 MW of wind generation.  Having the ability to store some of this renewable energy for later delivery will help to eliminate transmission constraints that can prevent energy from being delivered to consumers.

The battery storage facility is one of two such large systems in the state.  The other one is a 20 MW battery storage system developed by Key Capture Energy in Stillwater in Saratoga County.  That project, which was funded by NYSERDA under the state’s Bulk Storage incentive program, is connected to the wholesale transmission network and is a revenue source for Key Capture, an independent utility-scale battery storage developer based in Albany.

The new storage project’s location is an ideal opportunity to spotlight the value of energy storage given the proximity of the hydropower project and extensive wind resources.  Being able to store renewable energy will improve transmission of the state’s electric power to downstate markets as well as help meet the state’s goals for reducing its carbon footprint and increasing its reliance upon renewable energy.

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Construction begins on NYPA’s second large-scale storage project

Photo courtesy of ceedub13, CC BY 2.0.

Earth Wise is a production of WAMC Northeast Public Radio.

The Dangers Of Negative Emissions Technologies | Earth Wise

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Reducing carbon emissions is not easy and there are plenty of people who don’t even want to try for various reasons, generally related to their perceived economic interests and convenience.  As a result, there is a great deal of interest in so-called negative emissions technologies or NETs.   These are methods for removing carbon dioxide from the atmosphere.  Even the UN Intergovernmental Panel on Climate Change assumes that NETs will play a role in mitigating the effects of climate change and meeting international goals.

The most widely studied approaches to negative emissions technology are bioenergy with carbon capture and storage – which entails growing crops for fuel, and then capturing and burying the CO2 produced from burning the fuel; planting more forests; and direct air capture, which involves actually pulling CO2 out of the air and storing it – probably underground. 

A new study published in Nature Climate Change points out that none of these technologies has even been tried at the demonstration scale, much less at the massive levels required to make a dent in current CO2 emissions. 

Their analysis of the biofuel and reforestation strategies show that each would take up vast land and water resources already needed for agriculture and nature.  Air capture uses less water than the other two approaches, but still uses quite a bit and even more energy, which if supplied by fossil fuels, would offset the benefits of carbon capture.

Negative emissions technologies may well play an important role in combating climate change, but it is essential that we understand what the consequences will be from implementing them.  We need to know the pitfalls that could arise.  It would be a major mistake to simply count on NETs to be some kind of silver bullet.

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Remove CO2 from the air? Don’t bet on it before examining costs, researchers say

Photo, posted January 11, 2008, courtesy of Al Pavangkanan via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Solar On Commercial Buildings | Earth Wise

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The United States installed 3.6 gigawatts of photovoltaic solar capacity in the first quarter of this year to reach a total installed capacity of 81.4 GW.  That is enough to power about 16 million American homes.  More than 2/3 of that capacity has been installed during the past five years.  

There has been a boom in solar installations in recent years and, until the Covid-19 pandemic stuck, 2020 was expected to be the biggest year yet.  Now the unprecedented health, social, and economic conditions in our country creates great uncertainty in such forecasts.

Nevertheless, the opportunities for growth in solar power continue to be substantial.  A new report from the energy research firm Wood Mackenzie looked at the prospects for using the roof space of commercial buildings for solar power.

Currently, just 3.5% of commercial buildings in the U.S. have solar panels on their roofs.  Another 1% of those buildings are attached to solar projects located off-site.  The report looked at how many buildings are potential targets for solar projects.

After accounting for buildings that are too small or that use too little electricity to make solar power a worthwhile investment, the report estimated that 70% of commercial buildings in the U.S. – amounting to some 600,000 sites – are candidates for solar installations.  Doing this would provide 145 GW of new solar capacity, which is nearly twice as much as currently exists in this country. 

Commercial solar installations have their own unique logistical and financial challenges.  While utility solar can scale to lower costs and residential solar has financing opportunities, commercial solar has neither.  But ultimately, it represents an important opportunity for our future energy system.

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U.S. Commercial Rooftops Hold 145 Gigawatts of Untapped Solar Potential

Photo, posted June 25, 2014, courtesy of Rob Baxter via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Hacking Photosynthesis | Earth Wise

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A team led by the University of Illinois has been pursuing a project called Realizing Increased Photosynthetic Efficiency or RIPE, which has the aim of improving photosynthesis in order to provide farmers with higher-yielding crops in an increasingly challenging climate.  Photosynthesis is the natural, sunlight-powered process that plants use to convert carbon dioxide into sugars that fuel growth, development, and for us, crop yield.

If we think of photosynthesis as a factory line composed of multiple machines, the growth of plants is limited by the slowest machines in the line.  The RIPE project has identified some steps in photosynthesis that are slower than others and are attempting to enable plants to build more machines to speed up those slower steps.

The researchers modeled a total of 170 steps in the process of photosynthesis to identify how plants could manufacture sugars more efficiently.  In the study, the team increased crop growth by 27% by resolving two constraints:  one in the first part of photosynthesis where plants turn light energy into chemical energy and one in the second part when carbon dioxide is turned into sugars.

The researchers effectively hacked photosynthesis by adding a more efficient transport protein from algae to enhance the energy conversion process. 

In the greenhouse, these changes improved crop productivity by 52%, but in field trials, which are a more important test, these photosynthetic hacks boosted crop production by 27%.

Ultimately, the team hopes to translate these discoveries to a series of staple food crops, such as cassava, cowpea, corn, soybean and rice, which are needed to feed the world’s growing population this century.

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Photosynthetic hacks can boost crop yield, conserve water

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

Earth Wise is a production of WAMC Northeast Public Radio.

Generating Hydrogen From Poor-Quality Water | Earth Wise

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Hydrogen could be the basis of a complete energy system.  It could be stored and transported and could be used to power vehicles and to generate electricity in power plants.  Proponents of the so-called hydrogen economy contend that hydrogen is the best solution to the global energy challenge.  But among the challenges faced by a hydrogen economy is the development of an efficient and green method to produce hydrogen.

The primary carbon-free method of producing hydrogen is to break down water into its constituent elements – hydrogen and oxygen.  This can be done in a number of ways, notably by using electricity in a process called electrolysis.  A method that seems particularly attractive is to use sunlight as the energy source that breaks down the water molecule.

While there is an abundance of water on our planet, only some of it is suitable for people to drink and consume in other ways.    Much of the accessible water on earth is salty or polluted.  So, a technique to obtain hydrogen from water ideally should work with water that is otherwise of little use to people.

Researchers in Russia and the Czech Republic have recently developed a new material that efficiently generates hydrogen molecules by exposing water – even saltwater or polluted water – to sunlight. 

The new material is a three-layer structure composed of a thin film of gold, an ultra-thin layer of platinum, and a metal-organic framework or MOF of chromium compounds and organic molecules.  The MOF layer acts as a filter that gets rid of impurities.

Experiments have demonstrated that 100 square centimeters of the material can generate half a liter of hydrogen in an hour.  The researchers continue to improve the material and increase its efficiency over a broad range of the solar spectrum.

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New Material Can Generate Hydrogen from Salt and Polluted Water

Photo courtesy of Tomsk Polytechnic University.

Earth Wise is a production of WAMC Northeast Public Radio.

A Fabric To Keep You Cool | Earth Wise

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About 10% of all electricity consumption in the U.S. is devoted to keeping us cool with air conditioning and other methods.  Researchers at two universities in Shanghai, China have developed a new material that can be made into clothing that cools the wearer without using any electricity.

The new fabric transfers heat, allows moisture to evaporate from the skin, and repels water.  Cooling off a person’s body is much more efficient than cooling off an entire room or a building.  There have been textiles and types of clothing designed to perform the cooling function, but most of those have disadvantages.  These include some combination of poor cooling capacity, high energy consumption, complex and time-consuming manufacturing, and high cost.

The researchers wanted to develop a personal cooling fabric that can efficiently transfer heat away from the body while at the same time being breathable, water resistant and easy to make.

The new fabric is made by electrospinning an ordinary polyurethane polymer with a water-repelling fluorinated version of polyurethane polymer along with a thermally conductive filler composed of boron nitride nanosheets.  The resultant material is a nanofibrous membrane that repels water from the outside but has large enough pores to allow sweat to evaporate from the skin and air to circulate. 

Tests of the membrane demonstrated higher thermal conductivity than other conventional or high-tech fabrics.  Used in clothing, the material would be more effective than previous fabrics in conducting heat away from the body. It may be possible to beat the heat without turning on the AC.   These membranes could also be useful for solar energy collection, seawater desalination, and thermal management of electronic devices.

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New fabric could help keep you cool in the summer, even without A/C

Photo courtesy of the American Chemical Society on Youtube.

Earth Wise is a production of WAMC Northeast Public Radio.

Better Paint For Cooler Buildings | Earth Wise

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A research team led by scientists at UCLA have developed a super-white paint that reflects as much as 98% of incoming heat from the sun.  Such paint, if used on rooftops and other parts of buildings, could have a major impact on reducing the costs of keeping buildings cool.

Passive daytime radiative cooling is a well-known method to keep buildings cooler.  By having building surfaces reflect sunlight and radiate heat into space, building temperatures can be significantly lowered.  This in turn cuts down on air conditioner use and associated carbon emissions.

A roof painted white will result in lower indoor temperatures than a darker roof.  But a white roof will do even more:  it can reject heat at infrared wavelengths that are invisible to our eyes.  This results in even more radiative cooling.

The best performing white paints currently available reflect about 85% of incoming solar radiation.  The rest is absorbed by materials in the paint.  The new research has identified simple modifications in paint ingredients that lead to a major increase in reflectivity.

Current reflective white paints use titanium dioxide, which absorbs UV radiation and therefore heats up under sunlight.  The researchers studied replacing it with other substances such as barite – an artist’s pigment – or with powdered Teflon, both of which allow the paint to reflect more of the sun’s radiation. 

Many cities are encouraging the use of cool-roof technologies on new buildings.  Using the most reflective coatings possible on rooftops, if applied on a sufficiently large scale, could have a real impact on climate change as well as saving significant amounts of energy used for running air conditioners in buildings.

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UCLA-led Team Develops Ways to Keep Buildings Cool with Improved Super White Paints

Photo, posted August 15, 2012, courtesy of Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

WAMC Northeast Public Radio

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