photovoltaic

The Potential Of Artificial Photosynthesis | Earth Wise

August 2, 2021 By EarthWise Leave a Comment

The sun is the primary source of energy on the earth. Enough solar energy hits the earth in one hour to meet all of human civilization’s energy needs for an entire year. The two leading forms of renewable energy – photovoltaic solar power and wind power – are ways of making use of the sun’s energy. Wind power is indirectly provided by the sun; photovoltaic power uses sunlight to generate electricity.

The most efficient use of solar energy on the planet is one perfected by plants millions of years ago: photosynthesis. Photosynthesis is a complex sequence of processes by which plants convert sunlight and water into usable energy in the form of glucose. Plants utilize a combination of pigments, proteins, enzymes, and metals to perform their magic. If we can develop artificial photosynthesis, it would be a dramatic improvement of humans’ ability to power society cleanly and efficiently. Whereas photovoltaics capture about 20% of the sun’s energy, photosynthesis stores 60% of the sun’s energy as chemical energy.

Researchers across the globe are working to develop artificial photosynthesis. A group at Purdue university has been making progress in trying to mimic the ability of leaves to collect light and split water molecules to generate hydrogen. This is a critical step in photosynthesis that is accomplished by protein and pigment complexes known as “photosystems II”. The Purdue group is experimenting with these proteins and various synthetic catalysts in order to try to develop artificial leaves based on abundant, nontoxic materials.

It is likely to take a decade or more for artificial photosynthesis technology to become part of our energy system, but its ultimate potential is enormous.

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Soaking up the sun: Artificial photosynthesis promises a clean, sustainable source of energy

Photo, posted June 14, 2007, courtesy of Alex Holyoake via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Recycling Solar Panels | Earth Wise

October 1, 2020 By EarthWise Leave a Comment

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

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

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

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

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

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

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

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

Earth Wise is a production of WAMC Northeast Public Radio.

Solar On Commercial Buildings | Earth Wise

September 17, 2020 By EarthWise Leave a Comment

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.

A Second Life For Electric Car Batteries | Earth Wise

June 17, 2020 By EarthWise Leave a Comment

The number of electric cars around the world is growing steadily. Battery technology continues to improve and the battery packs in the cars can have a long life. Generally, the batteries are considered to require replacement only when their range has dropped below 80% of its original value. Many are warranted to last for 8 to 10 years or more than 100,000 miles. Some seem to do much better than that.

But however long it takes, there will eventually be a wave of used batteries whose performance is no longer deemed sufficient for vehicle use. A new study, published in the journal Applied Energy, looked at the application of used vehicle batteries as backup storage for grid-scale solar photovoltaic installations where they could perform for more than a decade in this less demanding role.

The study looked at the economics of several scenarios including running a solar farm with no battery back up, running the same farm with brand-new batteries, and running the farm with a battery array made of repurposed vehicle batteries.

They found that the used EV battery array, if managed properly, could be a good, profitable investment provided that the batteries cost less than 60% of their original price. They looked at the technical issues of screening batteries and combining batteries from different cars to work together. They also looked at the economics of removing batteries from cars, collecting them, checking them over, and repackaging them.

Overall, they found that reusing vehicle batteries could ultimately meet half the forecasted demand for renewable energy backup storage over the next 10 years and would be both a technical and an economic success story.

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Solar energy farms could offer second life for electric vehicle batteries

Photo, posted June 10, 2011, courtesy of Nick Ares via Flickr.

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.

Lots Of Renewable Energy Jobs

August 16, 2019 By EarthWise Leave a Comment

According to the International Renewable Energy Agency, there were 11 million people employed in renewable energy worldwide in 2018. This compares with 10.3 million in 2017. So roughly three-quarters of a million new jobs were added last year. As more and more countries manufacture, trade and install renewable energy technologies, renewables jobs continue to reach new high levels.

The geographic footprint of renewable energy jobs is changing. Until now, renewable energy industries have remained relatively concentrated in a handful of major markets such as China, the US, and the European Union. But more recently, East and Southeast Asian countries have emerged alongside China as key exporters of solar technology. Malaysia, Thailand, and Vietnam were responsible for a greater share of growth in renewables last year. Overall, Asia has a 60% share of renewable energy jobs worldwide.

Beyond climate goals, low-carbon economic growth has become a driver for renewables technology. Renewables deliver on all the major elements of sustainable development: environmental, economic and social.

The solar photovoltaic industry continues to be the most dynamic renewable enterprise. It accounts for a third of the renewable energy workforce with more than three million jobs.

Biofuel jobs were up by 6% to over 2 million. Wind power supports 1.2 million jobs, with onshore projects predominant. But the offshore wind segment is gaining traction. Hydropower is still the largest installed capacity of all renewables but is now only expanding slowly. The hydropower sector employs 2.1 million people directly, three-quarters in operations and maintenance.

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Renewable energy market employs 11 million in 2018 – IRENA

Photo, posted January 11, 2012, courtesy of the Oregon Department of Transportation via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

A Giant Solar Farm In Dubai

June 26, 2019 By EarthWise Leave a Comment

Like many places in the Middle East, Dubai made its fortune from oil. But the Emirate’s oil resources are limited, and its economy has evolved in other directions. Today, oil provides less than 5% of Dubai’s revenues; its economy relies on revenues from trade, tourism, aviation, real estate, and financial services.

Dubai is also away from fossil fuels to meet its energy needs. A monumental construction project is underway deep within Dubai’s desert interior which will be the largest solar energy facility in the world.

The Mohammed Bin Rashid Al Maktoum Solar Park – named after Dubai’s ruler – has been under development for 7 years. Total investment in the project will be nearly $14 billion when it is completed in 2030. It will have a total capacity of 5,000 megawatts, enough to power 1.3 million homes. Only some large hydroelectric power plants, the largest nuclear power plants, and a couple of Asian coal plants have more generating capacity.

Phases one and two of the project are already complete and feature more than 2 million solar panels. Phase three – well along the way in construction – will add another 3 million solar panels and should be completed next year.

Phase four will not involve solar panels but instead will make use of the world’s tallest concentrated solar power tower. It will use mirrors to focus sunlight at the top of the tower to heat up molten salt that will power steam turbines to generate electricity and will be able to operate long after the sun goes down.

Currently, the Tengger Desert Solar Park in China is the largest photovoltaic park in the world, but a colossal farm in India will take its place in a few years. Big solar is getting bigger all the time.

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