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Cutting The Cost Of Energy Storage | Earth Wise

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The cost of both solar and wind power continues to drop making the two renewable energy sources the cheapest way to make electricity in more and more places.  Given the virtually inexhaustible supply of both wind and sun power, these clean electricity sources can in principle meet all our energy needs.  The hang up is that both of them are intermittent sources – the wind doesn’t blow all the time and the sun doesn’t shine all the time.

The solution to the intermittency problem is energy storage.  If energy produced by wind and sun can be stored so it can be made available for use at any time, then the goal of having 100% clean energy can be realized.

Energy storage technology has continued to improve over time and to get cheaper.  The Department of Energy recently announced a new initiative aimed at accelerating both of these trends.

The new program – called Long Duration Storage Shot –  has the goal of reducing the cost of grid-scale, long-duration energy storage by 90% within this decade.

Long-duration energy storage is defined as systems that can store energy for more than ten hours at a time.  Such systems can support a low-cost, reliable, carbon-free electric grid that can supply power even when energy generation is unavailable or lower than demand.  With long-duration storage, solar-generated power can be used at night.

The program will consider multiple types of storage technologies – electrochemical (that is: batteries), mechanical, thermal, chemical carriers, and various combinations thereof.  Any technology that has the potential to meet the necessary duration and cost targets for long-term grid storage are fair game for the program.

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DOE announces goal to cut costs of long-duration energy storage by 90%

Photo, posted October 16, 2017, courtesy of UC Davis College of Engineering via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Climate Change And Kenya’s Tana River Basin | Earth Wise

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The Tana River is the longest river and most important waterway in Kenya.  It flows 620 miles from its headwaters in the Abderdare mountain range and Mount Kenya to the Indian Ocean.  The Tana River produces approximately half of the country’s electricity, and supplies Nairobi, the capital of Kenya, with 80% of its water.   

According to the United Nations Environment Programme, eight million people live along the Tana River, where coffee, tea, corn and other crops are grown for export, and fishing and cattle grazing help produce food for large portions of the country’s population. 

But the long-term ability of the river to provide these and other essential services is increasingly under threat due to many factors, including pollution, soil erosion, deforestation, and poor land use practices.   

Climate change is also complicating matters.  According to new research from the University of East Anglia, many species within the Tana River Basin will be unable to survive if global temperatures continue to rise at the current pace.  However, the study, which was recently published in the journal PLOS ONE, also found that many of these species could be saved if the world could meet the climate goals of the Paris Agreement. 

Globally, climate and land use changes are the two biggest threats to biodiversity.  According to researchers, 36% of the Tana River Basin has already been converted to agriculture. 

The research team says stronger commitments on climate change are needed from global leaders.  The climate and biodiversity crises can only be solved with urgent action to reduce global greenhouse gas emissions. 

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The impact of climate change on Kenya’s Tana river basin

Economics of Ecosystem Services of the Tana River Basin

Photo, posted August 19, 2010, courtesy of Luigi Guarino via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

The Potential Of Artificial Photosynthesis | Earth Wise

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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.

Floating Renewable Energy | Earth Wise

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A team of researchers at Texas A&M University believes that the next generation of offshore energy could come in the form of a synergistic combination of multiple renewable energy generators installed on a floating offshore platform.

Their concept for the ocean renewable energy station comprises wind, wave, ocean current, and solar energy elements that could generate electricity for anything from a coastal or island community to a research lab or military unit.  The station would be tethered to the sea bottom and could be used in locations where the water depth increases quickly, such as along the U.S. Pacific Coast or Hawaii.

Offshore wind is already commercially competitive, while wave-energy converters so far have been less cost-effective and only useful for specialized, smaller-scale applications.  The proposed ocean renewable energy station would make use of multiple different methods of electricity generation and incorporate innovative smart materials in the wave energy converters that respond to changes in wave height and frequency and allow for more consistent power production.

Denmark is already building a huge multi-source, multi-purpose ocean energy island.  This world’s first energy island will be 30 acres in area and serve as a hub for 200 giant offshore wind turbines generating 3 GW of electric power.  It is the largest construction project in Danish history, and will cost an estimate $34 billion.  As well as supplying other European countries with electricity, the goal is to use the new offshore island to produce green hydrogen from seawater, which can also be exported.  Large battery banks on the island will store surplus electricity for use in times of high demand.

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Research Underway On Floating Renewable Energy Station

Photo, posted September 27, 2014, courtesy of Eric Gross via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Record Carbon Dioxide Levels | Earth Wise

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The coronavirus pandemic caused a temporary dip in the burning of fossil fuels around the world as many human activities were diminished or curtailed entirely.  Despite this, the amount of carbon dioxide in the atmosphere set a record in May, reaching the highest levels in human history.

Scientific instruments atop the Mauna Loa volcano in Hawaii measured an average of 419 parts per million for the month, according to analysis from both the Scripps Institution of Oceanography and the National Oceanic and Atmospheric Administration.

This level is about half a percent more than the previous record of 417 ppm, set in May of 2020.  Carbon dioxide is the largest greenhouse gas contributor driving global warming and, according to scientists, there hasn’t been this much of it in the atmosphere for millions of years.

Global emissions of carbon dioxide were actually 5.8 percent lower in 2020 than 2019, as a result of pandemic lockdowns.  This was the largest one-year drop ever recorded.  But humanity was still responsible for emitting more than 31 billion tons of carbon dioxide last year.  About half of that CO2 is absorbed by the world’s trees and oceans, but the other half lingers in the atmosphere for thousands of years, gradually warming the planet via the greenhouse effect.

As long as we keep emitting carbon dioxide, it is going to continue to pile up in the atmosphere.  The only way to stop it is for the world’s nations to zero out their net emissions, mostly by switching away from fossil fuels to technologies that do not emit carbon dioxide, such as electric vehicles fueled by wind, solar, or nuclear power.

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Carbon Dioxide in Atmosphere Hits Record High Despite Pandemic Dip

Photo, posted August 7, 2013, courtesy of Gerry Machen via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

California Offshore Wind | Earth Wise

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Offshore wind has been pretty much a non-starter in the U.S. until recently.  Now there is considerable activity in the Northeast Atlantic with major projects getting started off the coasts of Massachusetts, New York, and other eastern states.  The prospects for wind farms in the Pacific, on the other hand, have been pretty dismal.  There are significant logistical problems posed by a deep ocean floor and also opposition from the Navy that does not want obstacles for its ships.

A combination of progress in floating wind turbine technology and the arrival of an administration highly supportive of renewable energy technology has changed the situation.  In late May, the Navy abandoned its opposition to Pacific offshore wind and joined the Interior Department in giving support to allowing two areas off the California coast to be developed for wind turbines.

The plan allows commercial offshore wind farms in a 400-square-mile area in Morro Bay in central California, and in another area off the Humboldt Coast in Northern California.

The two California sites could support enough wind turbines to generate electricity to power 1.6 million homes.  That would make the California coast one of the largest generators of wind power in the world.  The forthcoming Vineyard Wind farm in Massachusetts is expected to have 84 giant turbines.  The two California sites could hold more than 300 turbines.

The offshore wind industry is booming around the world, especially near the coasts of Norway and the UK, where the water is shallow, and turbines can be anchored to the ocean floor.  By contrast, the Pacific Ocean floor drops steeply from the coastline, making it too deep to anchor wind towers.  The newly emerging technology of floating turbines is the key to establishing offshore wind in the Pacific.

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Biden Opens California’s Coast to Wind Farms

Photo, posted August 7, 2013, courtesy of Ray Bouknight via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Utility-Scale Solar In Upstate New York | Earth Wise

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The first operational utility-scale solar projects in upstate New York are expected to commence commercial operations by the end of this year.  A portfolio of eight projects comprising over 200 megawatts of generating capacity is being developed by CS Energy in partnership with Goldman Sachs Renewable Power Group and NYSERDA.

The projects include three 27-megawatt installations in the Capital Region – in Easton and Stillwater, three 27-megawatt installations in the Mohawk Valley – in Mohawk and Pattersonville, and two 27-megawatt installations in the Southern Tier – in Willet and Greene.

The projects will support more than 500 jobs and represent more than $160 million of private investment that is expected to generate over $80 million in benefits to local communities and regions.  Those benefits will come to local landowners, property tax jurisdictions, and to local contractors who will provide ongoing operations and maintenance support for the projects.

The projects are the result of New York’s Clean Energy Standard, established in 2016 as well as 2019’s Climate Leadership and Community Protection Act.  These initiatives made commitments that 70% of the electricity consumed in New York would be generated by renewable energy sources by 2030. 

CS Energy has built over 150 megawatts of solar projects in New York to date.  By the end of this year, that number will be close to 500 megawatts.  CS Energy recently opened a regional headquarters in Albany to further support the company’s growth. The Goldman Sachs Renewable Power Group owns and operates more than 2.3 gigawatts of clean power across the country.

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Upstate New York’s first utility-scale solar projects set to come online this year

Photo, posted October 16, 2019, courtesy of Jonathan Cutrer via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

The World’s Largest Tidal Device | Earth Wise

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Most of the world’s activity in renewable energy is focused on solar and wind power.  The use of both is expanding rapidly. But there is also marine energy to be exploited.  Ocean waves and tidal movements hold huge amounts of energy.  Estimates are that the European Union could get 15% of its power from marine sources.  But ocean energy is currently expensive and there are significant technical challenges still to be overcome.

The world’s largest tidal power device will soon begin testing off the coast of Scotland.  The 680-ton, 240-foot-long, airplane-shaped device will be connected to the European Marine Energy Center for testing. 

The device, built by the Scottish company Orbital Marine Power, is designed to produce 2 megawatts of electricity, enough to power 2,000 homes.   It has a pair of 52-foot-long turbines attached to two wings.

Compared to wind and solar power, the marine energy sector has been much slower to develop because of the many difficulties of working in harsh marine environments as well as the technical challenges associated with harnessing power from waves and tides. But ocean waves and tidal movements hold enormous amounts of energy and have the advantage that they are available at all times, unlike wind and solar energy, which are variable in nature. 

Experts say that the future of tidal energy lies with arrays of floating or sea-bottom-mounted turbines that capture the energy of tidal currents in unobstructed waters.  There are various places around the world where this is an attractive opportunity, most notably in Nova Scotia’s Bay of Fundy, where the world’s most extreme tides – rising and falling more than 50 feet – contain vast amounts of power.

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The World’s Largest Tidal Power Device Will Soon Begin Testing Off Scotland

Photo, posted May 18, 2017, courtesy of Chris via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Insanely Cheap Energy | Earth Wise

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The International Energy Agency, founded in 1974, keeps track of the world’s energy systems and anticipates how they are likely to change over time.  Policymakers around the world look to the agency’s annual World Energy Outlook publication for guidance.

In 2000, the agency made the prediction that by the year 2020, there would be a total of 18 gigawatts of photovoltaic solar power installed.  Within seven years, that number was already too small.

The IEA was not the only source to miss the mark on solar power.  The head of solar analysis at BloombergNEF in 2005 expected solar to eventually supply 1% of the world’s electricity.  It is already 3% and Bloomberg now predicts that it will be 23% by 2050 and expects that to be an underestimate. 

What has happened is that the world has unexpectedly gotten to the point where solar is the cheapest source of energy in most places.  Over the past decade, every time solar production capacity has doubled, its cost has dropped by 28%.

Historically, a combination of groundbreaking research in Australia and intense Chinese industrial development led to the creation of a massive new industry.  When Germany passed laws encouraging the use of solar power, suddenly there was massive global demand and a struggle to keep up with supply.

The industry had its fits and starts, and many players fell by the wayside.    But at this point, solar technology continues to get better and cheaper.  Market forces are pretty hard to beat and when solar technology can supply insanely cheap energy, it is going to be used in more and more places.

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‘Insanely cheap energy’: how solar power continues to shock the world

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

Earth Wise is a production of WAMC Northeast Public Radio.

Floating Solar In New York’s Capital Region | Earth Wise

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We have previously talked about installing solar arrays on the surface of bodies of water.  The idea is especially attractive in places like Japan where land resources are scarce.  There are several floating solar installations in the UK and the idea is starting to catch on elsewhere as well.

It is quite possible that the largest municipally owned floating solar array may get built in the city of Cohoes in New York’s Capital Region if a project under consideration for federal funding moves forward.

The proposal is for an installation of 8,000 solar panels to cover about 2/3 of the 10-acre Cohoes reservoir.  Cohoes has wanted to erect a solar installation to generate power for its buildings but needed to find suitable vacant land.  The 10-acre manmade reservoir could be an excellent location for a floating solar array.

Cohoes would be the first community in the US to build and own a floating array on a manmade reservoir and could serve as a model for municipalities across the nation.  Such a project makes additional use of land that is already municipal property.  According to the city, the 3.2-megawatt array would generate over 4 million kilowatt hours of electricity per year, saving the city $300-350,000 annually.

Cohoes is seeking $4.59 million in federal funding to support the project and has the support of U.S. Representative Paul Tonko for possible inclusion in the 2022 federal budget. 

Apart from generating electricity, putting solar panels on the surface of a reservoir reduces evaporation, lowers algae growth, and actually improves solar panel performance because of the cooling effect of the water.

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Cohoes reservoir could be a floating solar power pioneer

Photo courtesy of Michael Coghlan via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Progress Towards Carbon-Free Power | Earth Wise

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Climate change has driven countries, states, utilities, and corporations to set goals to eliminate power-sector carbon emissions.  So far, 17 U.S. states plus Washington, D.C. and Puerto Rico have adopted laws or executive orders to achieve 100% carbon-free electricity over the next couple of decades.  Forty-six U.S. utilities have pledged to go carbon-free no later than 2050.   Adding these together, these government and industry goals cover about half of the U.S. population and economy.

New research from the Lawrence Berkeley National Laboratory has analyzed historical trends to determine how much progress the power sector has already made in reducing emissions.  The study focused on the 2005 Annual Energy Outlook from the U.S. government’s Energy Information Administration.

If the previous growth in emissions had continued from 2005 to 2020, annual CO2 emissions would have risen from 2,400 to 3,000 million metric tons.  But actual 2020 emissions fell to only 1,450 metric tons.  So, by this metric, the U.S. power sector cut emission by 52% below projected levels.

According to the study, total consumer electricity costs were 18% lower than projected values, but meanwhile, the number of jobs in electricity generation was 29% higher. 

Among the driving forces for these trends were wind and solar power dramatically outperforming earlier expectations, delivering 13 times more generation in 2020 than projected. 

The study shows that dramatic changes in emissions are possible over a 15-year span, but much has to happen over the next 15 years to ensure the progress required to meet the ambitious goals set for emissions reductions.

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U.S. Power Sector is Halfway to Zero Carbon Emissions

Photo, posted April 18, 2020, courtesy of Roman Ranniew via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Improving Solar Cells With Human Hair | Earth Wise

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Researchers at the Queensland University of Technology in Australia have been able to improve the performance of perovskite solar cells using material made from human hair.

Perovskite solar cells are an up-and-coming technology that offers the possibility of making solar cells less expensive, more efficient, and flexible so that there could be solar-powered clothing, backpacks, or even tents for camping.  While the technology has been shown to be as effective in converting sunlight to electricity as currently available silicon technology, it faces problems with stability and durability.

The Australian research centered on the use of carbon nanodots to improve perovskite solar cell performance.  The nanodots were created in a rather unique way.  The carbon came from hair scraps from a Brisbane barbershop that were first broken down and then burned at nearly 500 degrees Fahrenheit. 

By adding a solution of the carbon nanodots into the process of making the perovskites, the dots formed a wave-like layer in which the perovskite crystals in the cells are surrounded by the carbon dots.  It serves as a protective layer, essentially a kind of armor, for the active portions of the material.

The result was solar cells with a higher power conversion efficiency and greater stability.  The researchers did not explain why they chose human hair as the source of carbon, but it does make for an interesting sidelight to the promising research.

Perovskite solar cells could be very important for spacecraft applications where reducing weight is paramount.  But in order to be able to use them for this purpose, perovskite solar cells will need to be able to cope with the extreme radiation and temperature variations in space.

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Carbon dots from human hair boost solar cells

Photo, posted October 3, 2009, courtesy of Arktoi via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

A Solar Power Boom In Texas | Earth Wise

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Texas has been a leader in wind energy for a number of years.  In 2020, wind made up 23% of the state’s generating capacity and provided 20% of in-state generation.  But although wind capacity in Texas has grown rapidly in recent years, solar power is expected to make up the largest share of the state’s capacity additions over the next two years.

Texas plans to add 4.6 gigawatts of utility-scale solar power this year and 5.4 gigawatts in 2022.  This will give the state a total capacity of 15 gigawatts, which will nearly catch up to California, the state with the most large-scale solar power.  California already has 16 gigawatts of installed solar capacity and plans to add about two more over the next two years.

The planned capacity for Texas will provide enough power for roughly 5 million homes, taking into account the intermittency of solar energy.  Much of the new solar capacity will be in the Permian Basin in West Texas, which is a particularly sunny place.  Because solar generation is greatest in the middle of the day, when wind generation is typically lower, the transmission line infrastructure already in place for the wind power will be adequate for the new solar installations.

The boom in solar power in Texas is driven in part by the federal solar Investment Tax Credit that is available to project developers as well as by the ever-lower cost of solar technology. 

One-third of the utility-scale solar capacity planned to come online in the U.S. in the next two years will be in Texas.  Currently, utility-scale solar only makes up 4% of electrical generating capacity in Texas, but that is clearly changing.

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Texas likely to add 10 GW of utility-scale solar capacity in the next two years

Photo, posted May 14, 2020, courtesy of Courtney Celley/USFWS via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

A Green Light For Commercial-Scale Offshore Wind | Earth Wise

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The Biden administration has given final approval to a project it hopes will usher in a new era of wind energy in the United States.  The greenlight was announced by the Department of the Interior on May 11.

The Vineyard Wind project intends to install up to 84 huge wind turbines about 12 nautical miles off the cost of Martha’s Vineyard, Massachusetts.  In total, Vineyard Wind could generate 800 megawatts of electricity, enough to power about 400,000 homes.  The construction project will create about 3,600 jobs.  The $2.8 billion project is a joint venture of the energy firms Avangrid Renewables and Copenhagen Infrastructure Partners.

The idea of a wind farm off the Massachusetts coast was conceived 20 years ago but ran into repeated setbacks, delays, and well-funded opposition from waterfront property owners concerned about what will ultimately be the barely discernable sight of tiny blips on the distant horizon.  The Trump administration moved to cancel the permitting process for Vineyard Wind, but the Biden administration revived the project in March as part of its greater efforts to tackle climate change.

Electricity generated by Vineyard Wind will travel via cables buried six feet below the ocean floor to Cape Cod, where they will connect to a substation and feed into the New England grid.  The project is expected to begin delivering wind-powered electricity in 2023.

The Biden administration says that it intends to fast-track permits for other wind projects off the Atlantic Coast and that it will offer $3 billion in federal loan guarantees for offshore wind projects and invest in upgrades to ports across the United States to support wind turbine construction.

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Biden Administration Approves Nation’s First Major Offshore Wind Farm

Photo, posted February 8, 2007, courtesy of mmatsuura via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Ever Cheaper Solar Power | Earth Wise

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The price of electricity from solar panels has been dropping dramatically over the last decade.  The average cost of utility-scale solar power has gone down more than 80% since 1980, making it the least expensive power source in many places.  The plunging price of solar power is one of the driving forces behind the transition to clean energy. 

The 2020 average cost of solar power was 4.6 cents per kilowatt-hour.  The Department of Energy has recently set a target of reducing the cost of solar power by more than half again by 2030, to an unsubsidized average of 2 cents per kilowatt-hour.  The 2-cent goal is not just the ordinary cost of electricity; it is the levelized cost of energy which is based on a formula that includes the cost of construction and operation of a power plant.

If the least expensive power source becomes that much cheaper, it will really shake the foundation of many energy debates.  One of these debates is how to meet the need for more interstate power lines to transport renewable energy from rural areas to population centers.   If large amounts of additional renewable energy sources are added, policymakers will need to work harder to reform the regulatory system to make sure that new interstate power lines get built.

If the average cost of solar power reaches 2 cents a kilowatt-hour, the actual price will be lower in sunnier regions and higher in those that get less sun.  However, the continuing decrease in solar electricity costs will actually have the greatest impact in the northern, less sunny regions, because solar power may not currently be the least expensive option there but it will become the cheapest alternative over time.

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Inside Clean Energy: What Happens When Solar Power Gets Much, Much Cheaper?

Photo, posted May 14, 2020, courtesy of Courtney Celley/USFWS via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Solar Cell Greenhouses | Earth Wise

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A recent study at North Carolina State University has shown that it can be feasible to use see-through solar panels in greenhouses to generate electricity.  The idea is to use semi-transparent solar panels on greenhouses that allow some of the light to get in for the plants to grow while making the greenhouses energy neutral or even allowing them to generate more power than they use.

The question is how the semi-transparent solar panels might affect greenhouse crops.  To investigate this issue, researchers grew crops of red leaf lettuce from seed to full maturity under a standard set of growing conditions – temperature, water, fertilizer, and CO2 concentration – but varied the light they get. 

A control group was exposed to the full spectrum of white light while three experimental groups were exposed to light through different types of filters that absorbed the particular wavelengths of light that would be absorbed by different types of semitransparent solar cells.

The researchers paid close attention to characteristics of the lettuce that are important to growers, grocers, and consumers:  general appearance, leaf number, leaf size, and weight.  The results were that the lettuce produced using all three kinds of filtered light was essentially identical to that produced in the control group.    Further research is underway looking at how harvesting various wavelengths of light affects biological processes for lettuces, tomatoes, and other crops.

Getting growers to use solar-powered greenhouses would be very difficult if doing so would result in a loss of productivity.  But given these experimental results, it appears as though the decision will boil down to a simple economic argument about whether the investment in new greenhouse technology would be offset by energy production and its resultant savings.

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Study Finds Plants Would Grow Well in Solar Cell Greenhouses

Photo, posted April 8, 2008, courtesy of Brian Boucheron via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

How Green Are Electric Cars? | Earth Wise

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Environmental groups, governments, and automakers are all promoting electric vehicles as an important technology to combat climate change.  For example, GM plans to stop selling gas-powered cars by 2035 and Volvo intends to be all-electric by 2030.

There are still those who question how green electric vehicles actually are.  All products and technologies do have their environmental impacts.  In general, today’s electric cars produce significantly fewer planet-warming emissions than gas-powered cars, but there are factors that affect the results for specific vehicles.

The biggest issue is the source of electricity used to charge up the cars.  In places where coal still provides a substantial fraction of electric generation, electric cars don’t fare as well.  But coal’s contributions to the grid are declining rapidly and even cleaner fossil fuels like natural gas are gradually being replaced by green generation from wind and solar power.  If the grid was entirely carbon-free, then there would be no emissions associated with operating the vehicle.

MIT has created an interactive online tool that incorporates a comprehensive set of factors contributing to the emissions associated with cars:  what it takes to manufacture the cars, how much gasoline conventional cars burn, and where the electricity to charge electric vehicles comes from.

The tool provides information like the average amount of carbon dioxide emitted for every mile driven over a car’s lifetime. 

Results will vary with location and various other vehicle factors, but in the great majority of cases, electric cars are much greener than gasoline cars, and as the grid becomes greener, the cars will become greener as well.

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CarbonCounter 2021

How Green Are Electric Vehicles?

Photo, posted January 29, 2020, courtesy of Tony Webster via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Red Hot Chili Solar Panels | Earth Wise

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

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

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

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

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

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

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

Earth Wise is a production of WAMC Northeast Public Radio.

What’s The Best Way To Reduce Emissions? | Earth Wise

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A carbon tax is a fee imposed on the burning of carbon-based fuels, like coal, oil, and gas.  It’s one way to make the users of carbon fuels pay for the climate damage caused by releasing carbon dioxide into the atmosphere. 

According to a new study by researchers at Ohio State University, putting a price on producing carbon is the cheapest and most efficient policy change that legislators can make in order to reduce climate change-causing emissions. 

The case study, which was recently published in the journal Current Sustainable/Renewable Energy Reports, looked at the impact that a variety of policy changes would have on reducing carbon dioxide emissions from electricity generation in Texas. The researchers found that assigning a price to carbon, based on the cost of climate change, was most effective. 

The study did not look at how policy changes might affect the reliability of the Texas power system, an important consideration after the failure of the state’s power grid following winter storms in February. 

But the study did examine other policies and found that they were either more expensive or not as effective, including mandates that a certain amount of energy in a portfolio come from renewable sources.  Subsidizing renewable energy sources was also found to be less effective. 

According to researchers, market-based solutions have previously proven effective combating environmental issues.  For example, a cap-and-trade approach was used to reduce levels of sulfur dioxide, one of the chemicals that causes acid rain. 

For the sake of the climate, we should probably tax carbon. 

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Want to cut emissions that cause climate change? Tax carbon

What’s a carbon tax?

Photo, posted June 5, 2011, courtesy of John Englart 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.

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