solar power

Figuring Out Photosynthesis | Earth Wise

March 16, 2020 By EarthWise Leave a Comment

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.

Extreme Heat From Solar Power | Earth Wise

January 23, 2020 By EarthWise Leave a Comment

Renewable sources are playing a growing role in meeting our energy needs, but one place where they have continued to fall short is in industrial processes that require extreme heat. These include the cement, steel, and glass industries, among others. These industries account for a significant amount of CO2 emissions because the most effective way to reach the necessary temperatures continues to be combustion of fossil fuels. The cement industry alone accounts for 7% of global emissions and the need for cement continues to grow.

A previously stealthy startup company backed by Bill Gates and fellow billionaire Soon-Shiong has made a breakthrough in the area of using solar energy to achieve high temperatures. The company, called Heliogen, has created a solar oven that is capable of generating heat above 1800 degrees Fahrenheit, which is enough for high-temperature industrial processes.

The Heliogen technology uses concentrated solar power to generate heat. Concentrated solar power uses arrays of mirrors to reflect sunlight and focus it to a single point. That technology is not new; there are systems that use it to produce electricity and, to some extent, heat for industry. But it could not achieve high enough temperatures for producing cement or steel.

The new system uses computer vision software, automatic edge detection and other sophisticated technologies to focus the sun’s rays far more finely than ever before and thereby generate far higher temperatures at the focal point.

Heliogen is now focused on demonstrating how the technology can be used in a large-scale application, such as cement-making. The selling points to industry are that not only will there be no emissions generated, but that the fuel needed to obtain their extreme heat will be free.

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Secretive energy startup backed by Bill Gates achieves solar breakthrough

Photo courtesy of Heliogen.

Earth Wise is a production of WAMC Northeast Public Radio.

More Solar And Wind Power In The U.S.

January 2, 2020 By EarthWise Leave a Comment

According to the U.S. Energy Information Administration, both wind and solar power are contributing more and more to total electrical generation in the United States. For the first 8 months of 2019, the combination of wind and solar power accounted for almost 10% of U.S. electrical generation.

Solar, including small-scale PV systems on home rooftops, grew by almost 14% compared to the first eight months of 2018 and accounted for more than 2.7% of total electrical output. In fact, small-scale solar generation increased by 19% and provided nearly a third of all the solar power in the country.

Wind energy in the U.S. increased by 4.4%, accounting for almost 7% of the country’s electricity.

Overall, renewable energy sources – which include biomass, geothermal, hydropower, solar, and wind – accounted for 18.49% of net domestic electrical generation during the first 8 months of 2019. The non-hydro renewable sources actually accounted for over 11% of total electricity production and saw a year-over-year growth of 6%.

Outside of renewables, nuclear-generated electricity declined by 0.6% and coal power dropped by almost 14%. Much of the coal generation was replaced by natural gas, which grew by 6.5% compared to the previous year.

Renewables now accounting for nearly 20% of overall electricity generation in the US represents significant progress. But the variations by state continue to be substantial. For example, while Vermont gets 99% of its power from renewables, Ohio gets only 2%.

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Solar and wind energy provide almost 10 percent of total generation in the US in 2019

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

Earth Wise is a production of WAMC Northeast Public Radio.

Stranded Coal Assets In Japan

November 25, 2019 By EarthWise Leave a Comment

Japan is facing a looming financial problem as a result of heavy investments in coal technology that may quickly become stranded assets as renewable energy sources become increasingly inexpensive.

Japan is gradually adding more ambitious policies with regard to climate change including goals to reduce emissions and to have renewables become the main source of power over the next three decades. But despite these policy efforts, Japan is still investing heavily in coal power. Japan currently has 21 new coal projects with over 11 GW of under-construction, permitted or pre-permitted coal capacity. But these tens of billions of dollars in assets would have to be closed prematurely in order to remain consistent with the goals of the Paris Climate Agreement.

According to a new report by the Carbon Tracker Initiative, a financial think tank, and the University of Tokyo, offshore wind power will be cheaper than coal in Japan by 2022, new solar cheaper by 2023, and onshore wind less expensive by 2025. The price of offshore wind is already comparable to existing coal power in Japan. Japan had a total of 55.5 GW of solar capacity last year and has the potential to reach 150 GW by 2030.

The report notes that 42% of the global coal fleet likely became unprofitable last year and this could rise to 72% by 2040. The authors contend that building coal power today equals high-cost power and financial liabilities tomorrow. The planned and operating coal capacity in Japan is partially protected by regulations that give coal generators an unfair advantage in the marketplace. Ultimately, the stranded coal assets are likely to be passed down to consumers through higher power prices.

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Land of the Rising Sun and Offshore Wind

Photo, posted April 25, 2019, courtesy of Jen via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Solar-Powered Desalination

October 4, 2019 By EarthWise Leave a Comment

Turning seawater into drinking water is an energy-intensive process and is therefore pretty expensive. Worldwide, one third of people don’t have reliable access to safe drinking water and they are the least able to afford expensive ways to get it. By 2025, half of the world’s population is expected to live in water-stressed areas.

At a newly-constructed facility in Kenya, a nonprofit company called GivePower has built a desalination system that runs on solar power. The system started operating in the coastal area of Kiunga in July 2018 and can create nearly 20,000 gallons of fresh drinking water each day – enough for 25,000 people.

GivePower started in 2013 as a nonprofit branch of SolarCity, the solar-panel company that ultimately merged with Tesla in 2016. However, GivePower spun off as a separate enterprise shortly before that.

GivePower mostly focuses on building solar-energy systems to provide electricity across the developing world.

Desalination technology is not new, but it is notoriously energy-intensive because it requires high-power pumps. The GivePower system is integrated with a solar microgrid that makes use of Tesla batteries to store energy for when the sun is not shining.

Local residents pay about a quarter of one cent for every quart of water from the system. The Kiunga community has faced ongoing drought and before the GivePower system was installed, was forced to drink from salt water wells, which present serious health risks.

The GivePower system cost $500,000 to build and is expected to generate $100,000 a year, to be eventually used to fund similar facilities in other places.

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A solar-powered system can turn salt water into fresh drinking water for 25,000 people per day. It could help address the world’s looming water crisis.

Photo courtesy of GivePower.

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.

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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.

100% Renewables Does Not Necessarily Mean Carbon-Free

July 16, 2019 By EarthWise Leave a Comment

Hundreds of companies around the world have committed to use 100% renewable energy in order to fight climate change. But a new study from Stanford University points out that 100% renewable energy does not necessarily mean 100% carbon-free energy.

The problem is that the carbon content of electricity can vary a lot over the course of a day in many locations. Using yearly averages can overstate the carbon reductions associated with a particular power source, in some cases by significant amounts.

Suppose a California company purchases or generates enough solar power to match 100% or more of their electricity use over the course of the year. In reality, it may generate far more electricity than it uses during the afternoon and sell the excess. Then, at nighttime, it purchases power from the grid, which would be far more carbon-intensive if it involves the burning of fossil fuels.

But in Britain, for example, the situation is very different. With a high reliance on wind power, grid carbon intensity is actually lower at night. So very different consumption patterns over the course of a day would be less carbon-intensive.

If sufficient energy storage capacity can be implemented into the grid as well as suitable long-range transmission, these time-based fluctuations in the electricity supply could be ironed out. Until such time, electricity consumers need to evaluate the environmental benefits of their renewable strategies on an hourly basis rather than using averages. And the best strategies are entirely dependent upon the characteristics of the specific grid they interact with. The need for this kind of analysis will only grow as renewable generation expands. Transparent, precise and meaningful carbon accounting is necessary.

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100% renewables doesn’t equal zero-carbon energy, and the difference is growing

Photo, posted January 29, 2013, courtesy of U.S. Fish and Wildlife Service via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

The World’s Largest Storage Battery

May 24, 2019 By EarthWise Leave a Comment

Many homeowners are installing solar energy systems with battery backup. Energy stored in the battery can be used when the sun isn’t shining. As battery prices come down, utility-scale solar installations are also turning to battery-based energy storage.

Florida Power & Light has announced plans to build the world’s largest solar-storage combination facility in Manatee County. The 409-MW Manatee Energy Storage Center will be the largest solar-battery system by a factor of four. The specifics of the technology and source of the battery system components have yet to be announced.

The system, which is scheduled to be completed in late 2021, will be charged by a nearby FPL solar power plant. The plan is to discharge batteries during times of higher demand, thereby offsetting the need to run other power plants. As a result, there will be reduced emissions and customers will save as much as $100 million through avoided fuel costs.

Installing the mega-sized battery system will accelerate the retirements of two nearby 1970’s-era gas-fired generation units. At peak efficiency, the Manatee energy storage system will be able to power 390,000 homes for up to two hours.

FPL has already been pursuing the use of battery storage technology. Last year, they added a 10 MW battery storage system to its 74.5 MW Babcock Ranch Solar Energy Center in Charlotte County.

These large battery systems are increasingly practical because of dramatic reductions in lithium-ion battery costs. The levelized cost of electricity from lithium-ion batteries has declined a remarkable 38% just since the beginning of 2018. The economics of clean energy continue to get better and better.

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FP&L Plans World’s Largest Energy Storage Battery To Support Its Renewable Energy Goals

Photo, posted April 21, 2010, courtesy of Frank Starmer via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Lots Of Renewable Energy In Germany

April 29, 2019 By EarthWise Leave a Comment

As the contributions to the electrical grid from renewable sources continue to rise, people have expressed concerns about what might happen as sources like wind and solar energy become dominant. Not many years ago, there was a common concern that if wind and solar contributed more than about a quarter of the energy mix, the grid might become unstable or unreliable. Theoretical models looked at this situation but there hadn’t been much real-world data to look at.

One place where there is now real-world data on a large scale is Germany. Germany has been aggressively deploying both wind and solar energy for years as part of a national initiative called the Energiewende or energy transition. Germany recently increased its renewable energy goal from 55% to 65% by the year 2030. The increased share of renewables takes into account the decommissioning of aging nuclear and coal power plants.

A demonstration of the feasibility of such a goal occurred in the first week of March when renewable sources actually supplied nearly 65% of Germany’s electricity. Wind power alone provided nearly half of the country’s power. As a result, fossil fuel plants ran at a minimum output and nuclear facilities were shut down at night.

Germany has a very large domestic coal industry and indeed lignite coal generated an average of 24% of the country’s power last year. However, recently that share was down to just 12%. During that first week of March, solar power contributed more than 5% of Germany’s electricity, biomass 7.6%, and hydropower 3.5%.

While the week with 65% renewable set a record, the ongoing trend is very positive as well. In 2018, renewable energy generated an average of more than 40% of Germany’s electricity.

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Renewables Generated a Record 65 Percent of Germany’s Electricity Last Week

Photo, posted April 28, 2012, courtesy of Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

More Renewables Without Storage In Texas

February 27, 2019 By EarthWise Leave a Comment

Texas has a Texas-sized appetite for electricity and relies most heavily on natural gas, coal and nuclear power to get it. But in recent times, wind power has grown tremendously in the Lone Star State and it has already leapfrogged past nuclear power. Coal could be the next domino to fall.

In the past few years, solar power has become competitive with wind in terms of price. Texas is a large, coastal state in the sunny southwestern U.S. and has significant solar resources. As a result, the amount of solar power in Texas is now growing rapidly.

In order for a combination of solar and wind power to address the bulk of electricity demand in Texas, there needs to be a way to provide reliability that these intermittent sources don’t necessarily provide. Energy storage is a solution that ultimately is likely to be part of most electricity grids, but currently it is still expensive on a utility scale.

A new study from Rice University looked at the complementarity of solar and wind power in Texas. Complementarity refers to balancing the output of solar and wind systems. The peak performance of wind and solar occurs at very different times in different regions of the state. The study suggests that the right mix of solar and wind systems in the right parts of Texas could provide a continuously reliable energy system. On both a yearly and daily basis, wind and solar power resources in Texas complement each other in terms of peak performance. It is a matter of locating the solar power and wind farms in the right places.

With the Texas solar industry really starting to boom, there is a real opportunity to integrate far more renewable energy into the Texas grid.

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More Renewables with Less Energy Storage: Texas Shows How

Photo, posted June 8, 2018, courtesy of Laura Lee Dooley via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Liquid Fuel From The Sun

February 21, 2019 By EarthWise Leave a Comment

Most forms of energy we use ultimately come from the sun in one way or another. Even fossil fuels are the end product of millions of years of plant life that captured solar energy. The advantage fossil fuels have over direct solar power is that they are, in fact, fuels and therefore can be stored for use when needed.

Scientists in Sweden have now developed a specialized fluid that absorbs some of the sun’s energy, holds it for months or even years, and then releases it when needed. This solar thermal fuel is like a rechargeable battery for heat rather than electricity.

The special fluid is pumped through transparent tubes where ultraviolet light from the sun excites its molecules into an energized state. A compound called norbornadiene is converted into quadricyclane. The quadricyclane is a quite stable substance until it is passed over a cobalt-based catalyst, which causes it to turn back into norbornadiene and release copious amounts of heat.

Such a solar thermal fuel could be stored in uninsulated tanks in homes or factories or piped or trucked to where it was needed. It could then be used for water heaters, dishwashers, or clothes driers. The room temperature fluid quickly warms to about 183 degrees when passed over the catalyst, plenty warm enough for heating a home or office. Both the fuel and the catalyst are damaged very little by the reactions, so the process can be recycled many times.

There is much development work needed to optimize shelf life, energy density, good recyclability and other properties before this technology can be commercialized but there are at least 15 groups around the world now studying this intriguing way to get liquid fuel from the sun.

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Scientists transform sunlight into a liquid fuel that can be stored for 18 years

Photo, posted August 17, 2009, courtesy of Hiromichi Torihara via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Smog And Solar Power

January 22, 2019 By EarthWise Leave a Comment

China has been struggling with some of the worst air pollution in the world. Beijing frequently sits under a brown blanket made of exhaust gases from industry, cars and coal fires, which dump harmful particulate matter, soot, sulfur dioxide and nitrogen oxides into the air.

The human health consequences are severe. According to the World Health Organization,air pollution contributes to about 1.6 million premature deaths in China each year. World-wide, air pollution is implicated in over 7 million deaths annually.

Faced with this air pollution crisis, China has undertaken a wide variety of measures to improve its air and curb carbon dioxide emissions alongthe way. Among other things, China has invested heavily in the deployment of solar power and has plans for ever greater expansion of solar power in the future.

A study by researchers at ETH in Zurich looked at the impact of China’s air pollution on the production of solar energy. The smog in China’s cities reduces the amount of solar radiation that reaches the ground and therefore significantly reduces the power output of solar energy systems. According to the study, solar radiation would increase by an average of 11% nationwide as a result of strict air pollution control measures. In some places, cleaning up the air would result in 26% more energy production.

China’s electric power industry is the world’s largest electricity producer, having passed the United States in 2011. Two-thirds of the electricity in China still comes from coal, which, apart from the serious climate and health consequences associated with its use, continues to make it more difficult to switch to clean solar power. Much work remains to be done.

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Fighting smog supports solar power

Photo, posted February 7, 2014, courtesy of Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Energy Trends For A New Year

January 15, 2019 By EarthWise Leave a Comment

With a new year upon us, there are several energy trends to watch out for.

The most important one is that the fundamental shift toward slow-carbon technologies is continuing. This shift is taking place despite diminishing government policy support and even active government efforts to thwart it. There is just too much momentum to stand in the way of low-carbon energy technologies.

Analysts at Bloomberg New Energy Finance estimate that over the next 30 years over 11 trillion dollars will be invested in energy power generation and power storage assets with 85% of it aimed at zero-carbon emission. Dramatic reductions in green energy costs have resulted in legitimate cost competition between zero carbon sources of energy and fossil fuel generation.

In the coming year, battery technology will continue to play a growing role both as a storage medium for energy generated by sun and wind and for powering vehicles.

Another trend is that the world’s wealthiest economies are learning to grow without growing the demand for electricity. This is important in the battle to reduce overall emissions.

Another key issue is addressing the energy needs of people who have no meaningful access to it and there are around 1.5 billion people in that category. Emerging technologies based on solar power, wind energy, microgrids and other innovations mean that traditional power grids that remain out of reach to these people are not necessary. There is the potential to address those needs without contributing to climate change.

The world is struggling to deal with the growing problem of the changing climate, but there are trends that provide at least some hope that we can move in the right direction.

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