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The largest solar power plant

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The Middle East is known for its vast petroleum resources and oil has been its primary source of wealth.  But the desert region is now becoming a significant center for solar energy as well.  The world’s largest single-site solar park is the Mohammed bin Rashid Al Maktoum Solar Park, located in the United Arab Emirates.

Currently, 1 GW of solar is operational at the facility, but work is underway that will add 1.8 GW more capacity. Over 2.2 million solar panels have been installed to date and there will be more than 3.9 million by the time the next phase is completed. By the end of the decade, the capacity of the facility is expected to reach 7.2 GW, exceeding the original 5 GW target.  The plant will contribute about a third of Dubai’s total electricity capacity.

This solar plant will be one of the 15 largest power plants in the world.  Most of the largest ones are hydroelectric plants.  The biggest is the Three Gorges Dam in China, which has an enormous 22.5 GW capacity. The only non-hydro plant in the top 10 is the Jebel Ali natural gas plant, located in the United Arab Emirates.  China’s Jiuquan Wind Farm has a capacity of nearly 8 GW.  The largest power plant in the United States is the Grand Coulee Dam, which has a 6.8 GW capacity.

The world’s hunger for electric power continues to grow, especially with the surging use of AI technology.  As a result, there will be growing numbers of increasingly larger power plants.

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World’s largest solar park adds 1 GW

Photo courtesy of the Dubai Media Office.

Earth Wise is a production of WAMC Northeast Public Radio

Shrinking coal and the gas trap

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An important part of the 2015 Paris Climate Agreement is reducing the use of coal to produce electricity.  Coal is the dirtiest fuel in common use and not burning it is a way to greatly reduce emissions.  Ten years later, coal consumption around the world has decreased dramatically. 

The most convenient alternative to coal is natural gas, which is still a fossil fuel, but one that releases less carbon than coal.  As a result, around the world many countries have increasingly switched from coal to natural gas.

While the switch is a step in the right direction, it is also one that comes with an unintended consequence.  Economists at Stanford University have found that natural gas exports by countries have the effect of discouraging investments in renewable energy.  Over the long term, the result is increases in carbon emissions.  The Stanford researchers refer to this situation as ‘the gas trap’.

As a result of the gas trap, even countries that are very concerned about climate change and want to take action by abandoning the use of coal may end up reducing their investments in renewables and, ultimately, producing more emissions.

This problem comes about because replacing fossil fuels with renewables requires large investments and can take years before the renewables can fully compete with coal.  Natural gas, as a “transition fuel” gives countries time to develop renewable solutions.  But natural gas producers keep providing large amounts of their product at attractive prices so that customers buy more and more of it rather than investing in renewables.  The gas trap isn’t permanent or inevitable, but it is currently a problem.

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How the rush to quit coal is fueling a new ‘gas trap’

Photo, posted February 7, 2017, courtesy of Christian Collins via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

AI and greener cement

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Cement pretty much holds the modern world together.  The amount of cement required to create our infrastructure is almost incomprehensible.   By weight, humanity consumes more cement than food, about 3 pounds per person per day.  The cement industry produces around eight percent of global CO2 emissions, which is more than the aviation industry.  So, if the amount of emissions produced making concrete could be reduced by even a few percent, it would make a significant impact.

Cement plants utilize rotary kilns heated to 2,500 degrees Fahrenheit to burn ground limestone down to a substance called clinker.  That energy-intensive combustion process emits large amounts of carbon dioxide.  However, the combustion process accounts for much less than half of the emissions associated with making concrete.  The majority comes from the raw materials needed to produce clinker.

One strategy to reduce concrete emissions is to modify the cement recipe itself, replacing some of the clinker with alternative materials.  Some producers already make use of materials like slag from iron production and fly ash from coal-fired power plants.   

A team of researchers at the Paul Scherrer Institute in Switzerland is making use of machine learning to simulate and optimize cement formulations that would emit significantly less CO2 while maintaining the same high level of mechanical performance.  This AI-based approach eliminates time-consuming experiments and conventional complex simulations.

The Scherrer Institute seeks to discover new materials and the effort has already yielded some promising candidates.  The next steps will be testing some of these recipes in the laboratory. 

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AI paves the way towards green cement

Photo, posted July 3, 2007, courtesy of Tim Shortt via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Tracking emissions by satellite

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Carbon dioxide and nitrogen oxides are two of the most problematic human-generated air pollutants that negatively impact air quality, the climate, and human health.  Satellites are an important tool for monitoring emissions of these pollutants, but they have limitations.  For the most part, satellites have limited spatial resolution, meaning that they can’t reliably narrow down the source of emissions sufficiently to pin down a specific location such as a power plant. 

Until now, there have been no instruments that can detect both carbon dioxide and nitrogen oxide simultaneously with high spatial resolution.  Often just nitrogen oxide measurements are made, and carbon dioxide levels estimated based on the fact that both are emitted together with typical ratios.

A German research team from the Max Planck Institute and the Heidelberg Institute have developed a technology for the EnMAP environmental satellite to detect both gases with an unprecedented spatial resolution of 30 meters.  Data from the satellite makes it possible to track multiple sources of emission plumes over several tens of kilometers.

The EnMAP system was originally designed for remote sensing of land surfaces.  The new research demonstrates that reliable measurements of trace gases are possible even with an instrument not specifically designed for atmospheric observations.  When using it, it’s possible to determine the distribution of carbon dioxide and nitrogen oxide in emission plumes from individual power plants.  The ability to measure both gases individually means that conclusions can be drawn about the technology, efficiency, and operating mode of the systems being measured.

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German satellite measures CO2 and NO2 simultaneously from power plant emissions for the first time

Photo, posted September 19, 2020, courtesy of Sandor Somkuti via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Grid reliability and grid-edge resources

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A new study by MIT researchers looked at the potential for grid-edge resources to enhance the ability of the electric grid to respond to unforeseen power outages.  Grid-edge resources are devices found close to consumers rather than located near central power plants, substations, or transmission lines.  These include residential solar panels, storage batteries, electric vehicles, heat pumps, smart thermostats and smart water heaters.

These grid-edge devices can independently generate, store, or tune their consumption of power and increasingly, they are online internet-of-things devices.  The MIT study outlined a blueprint for how such devices could reinforce the power grid through a local electricity market.  Owners of grid-edge devices could subscribe to such a market and essentially loan out their device as part of a microgrid or local network as on-call energy resources.

Electric vehicles could provide power rather than consuming it when necessary.  Storage batteries could do the same.  Devices like smart dishwashers and thermostats would reduce their power demands when necessary.

In the event that the main power grid is compromised, an algorithm would determine which grid-edge devices were available and trustworthy and would either use them to pump power into the grid or reduce the power they are drawing from it in order to help mitigate the power failure. 

The MIT researchers illustrated this grid resilience strategy through a number of grid attack scenarios including failures from cyber-attacks and natural disasters.   Their analysis showed that various networks of grid-edge devices are capable of defeating various types of grid failures.

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Rooftop panels, EV chargers, and smart thermostats could chip in to boost power grid resilience

Photo, posted October 10, 2019, courtesy of Noya Fields via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

A big year for battery storage

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A decade ago, the ability of utilities to store large amounts of electricity in batteries was basically nonexistent.  In the past several years, growth in battery storage systems has exploded.  As of the end of November, the US had about 24 gigawatt-hours of storage capacity in place.  This is 71% more than just a year ago.  Nearly half of the battery storage in the US is located in California.  Texas, Arizona, and Nevada are also leaders in deploying battery storage.

Battery storage allows solar and wind generating plants to keep operating when there is reduced demand for their output and have the electricity that they produce be available later when demand rises.  Storing this excess electricity essentially extends the hours of the day when clean energy can be used.

Equally important, the existence of battery storage reduces the need for peaker plants, the fossil-fueled power plants that only turn on at times of peak demand, such as during hot afternoons.

There are 1,000 peaker plants in the US and they are generally heavily polluting, inefficient, and expensive to operate.  Some 63 million people live within a three-mile radius of one of them and are exposed to harmful pollutants like nitrogen oxides and sulfur dioxide.  Peaker plants also release more greenhouse gases than other power plants do for every unit of electricity they generate.

Many battery storage facilities are co-located with, or otherwise support, solar energy plants.  The amount of solar energy in the US is growing rapidly and surpassed the 100-gigawatt mark in 2024.  As solar power continues to expand, so will battery energy storage.

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Battery projects soared again in 2024

Photo, posted August 3, 2024, courtesy of the Bureau of Ocean Energy Management via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

A solar peaker plant

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Peaker plants are power plants that the grid makes use of during times of particularly high electricity demand.  The power they supply is typically high in cost and usually high in greenhouse gas emissions.  When operating the electricity grid, power sources are generally called upon in order of marginal cost.  Only when demand is very high do grid operators make use of the highest-cost assets that tend to be fossil-fueled power plants that can start and ramp up quickly. 

For years, there has been the idea that solar-powered peaker plants could eventually replace the polluting fossil-fueled ones.  Recently, the renewable energy developer, owner, and operator Arevon Energy began commercial operations of the Vikings Solar-plus-Storage Project in Imperial County, California.  It is the first utility-scale solar peaker plant in the United States.

The plant utilizes a 157-megawatt solar array combined with 150 MW and 600 MWh of battery energy storage.  It can shift low-cost daytime solar energy to higher-cost peak demand periods.  The result is a lowered cost of electricity for nearly one million customers of San Diego Community Power.

The project contradicts the often-held notion that renewable energy is inherently unreliable.  It can provide carbon-free electricity at specific times of critical need.  Typical hybrid solar + storage plants provide electricity during daylight hours and store only excess generation in their battery systems.  The Vikings project is specifically designed to shift the entirety of its generation from solar hours to the peak demand period.

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Arevon fires up the first solar + storage peaker plant in the U.S.

Photo, posted October 15, 2024, courtesy of Jay Inslee via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Manatees are not Florida natives

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Florida is very proud of its manatees.  It has a county named after them and has pictures of them on license plates.  These gentle creatures are part of Florida culture.  But recent research indicates that manatees – also known as sea cows – might only be relatively recent residents of the Sunshine State.

Manatees have been spotted in Florida waters for several centuries but might have only been tourists visiting briefly before returning to their home waters in the Caribbean in places like Cuba.

The new research suggests that manatees might not have actually taken up residence in Florida until after Europeans colonized the area in the 1500s.  There is a rarity of manatee bones on archaeological sites that date back further.  It was particularly striking that Crystal River, which is an epicenter for modern manatee populations, had little evidence of their presence in earlier times.

Even into the early 1900s, Florida newspaper reports treated manatee sightings as a spectacle rather than a common occurrence.  In the 1920s and 1930s, there started to be more routine sightings in places like yacht basins and canal harbors.  In the 1950s, manatees became more plentiful in Tampa Bay and Crystal River. The warming waters and human activities creating shallow warm water refuges increased manatee populations, particularly near places like power plants.

The current Florida manatee population is between 8,000 and 12,000 and is classified as threatened under the Endangered Species Act, an improvement over its previous endangered status.  But pollution is killing a lot of the seagrass that they eat, and their safety is by no means assured.

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Why manatees are likely not Florida natives

Photo, posted March 25, 2012, courtesy of David Hinkel / USFWS via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

New approaches to nuclear power

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The US is the world’s largest user of nuclear power.  Its 94 reactors supply nearly 19% of the country’s electricity. But the number of U.S. reactors has steadily fallen over the past 30 years and new nuclear power plants are a real rarity.  The reasons are a combination of perceived dangers following several nuclear accidents and the increasing costs associated with building plants that can meet a growing number of regulatory requirements.

There are recent developments associated with new advanced reactor technologies that may lead to a resurgence in the use of nuclear power.  Bill Gates’ energy company TerraPower is developing nuclear reactors that use sodium instead of water for cooling.  Such reactors operate at lower pressures and higher temperatures.  

Meanwhile, Kairos Power, a California-based energy company, has entered into an agreement with Google to build multiple small modular nuclear reactors that will supply electricity to that giant tech company.  The modular reactors use a molten-salt cooling system combined with a ceramic, pebble-type fuel in order to transport heat to a steam turbine to generate power.  The novel design of these reactors can reduce construction timelines, allow deployment in more places, and make final project delivery more predictable.

Surveys indicate that a majority of Americans favor the use of nuclear power, which has the advantages that it doesn’t create greenhouse gas emissions and can run 24-7.  But traditional nuclear power plants are too expensive and have too many potential problems.  These new nuclear power technologies may be the answer for allowing nuclear power to play an important role in the future energy system.

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New nuclear clean energy agreement with Kairos Power

Photo, posted May 16, 2016, courtesy of Steve Jurvetson via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Pollution in downwind states

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Air pollution is a serious health threat.  It is associated with asthma and can lead to chronic disease, cancer, and premature death.  Globally, air pollution kills 7 to 9 million people, and 200,000 Americans die from it each year.

There are multiple sources of air pollution including automobiles, power plants, and other industrial activities.  Exposure to pollutants such as nitrogen oxide, sulfur dioxide, and particulate matter does not require living or working near their sources.  Winds can carry pollution great distances including across state lines.  

The Clean Air Act included the EPA’s “Good Neighbor Plan”, which requires “upwind” states to implement plans to reduce emissions from power plants and other industrial sources.  However, three states – Indiana, Ohio, and West Virginia – along with various industrial companies and trade organizations sued the EPA when it tried to enforce these plans.  A recent Supreme Court decision to block a federal rule curbing interstate air pollution further complicates efforts to reduce emissions.

As a result, there is a disproportionate burden on downwind states.  They face major challenges in demonstrating and attributing air pollution to sources across state lines and pursuing legal actions to get the EPA to address their problems.

A recent study by the University of Notre Dame looking at all the complex issues related to interstate pollution underscored how the regulatory system continues to be hamstrung when attempting to address a serious threat to human health and the environment.

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Downwind states face disproportionate burden of air pollution

Photo, posted February 19, 2021, courtesy of David Wilson via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

China and carbon emissions

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China has been the biggest source of greenhouse emissions for nearly 20 years.  Its emissions surpassed those of the United States in 2006 and its fraction of the world’s emissions is now nearly a third.  Therefore, unless China’s emissions stop growing, the world’s emissions won’t either.

Recent data from China’s government and by energy analysts provides some reasons for optimism.  What is happening is that how China produces its electricity is changing.  Renewable sources are gradually replacing coal.

Last year alone, China installed more solar panels than the United States has in its entire history.  Nearly two-thirds of utility-scale wind and solar plants under construction are in China.  According to a report from Global Energy Monitor, China is developing more than eight times the wind and solar capacity currently being planned for the US.

Despite all this progress, China still generates 53% of its electricity from coal.  While this is the lowest share reported since its government began publishing energy data decades ago, it is still a major source of carbon emissions.  China is responsible for two-thirds of the world’s newly operating coal plants and still plans to build many more.  China accounts for about 60% of the world’s coal use.

China is investing heavily in pumped-storage hydropower along with its massive efforts in solar and wind power.  But if it is to meet existing and proposed new commitments to reduce emissions, it will need to be much more aggressive in reducing its dependence on coal.  Current predictions are that China’s emissions may soon no longer be increasing.  But what is needed is for them to start dropping and the sooner the better.

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Why the Era of China’s Soaring Carbon Emissions Might Be Ending

Photo courtesy of Mike Locke via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

A brief bout of bad air in Scotland

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Scotland, and the UK in general, used to suffer from sulfur dioxide pollution.  Industrial and domestic emissions, especially from burning coal, contributed heavily to urban air leading to the London smog of the 1950s and the acid rain of the 1980s.  But national air pollution agreements and various international measures have been highly successful in reducing sulfur dioxide emissions.  Desulfurization of coal-fired powerplants and the introduction of ultralow sulfur fuels among other measures have decreased sulfur dioxide emission by 98% since 1970. 

As a result, it came as quite a surprise on May 31st when Edinburgh saw sulfur dioxide levels higher than had been observed in over 30 years.  The levels greatly exceeded air quality objectives for 10 hours with concentrations even creeping towards workplace exposure limits.

What happened?  For once, it was nothing that people did.  Two days earlier, a volcanic fissure eruption took place in the Reykjanes Peninsula in Iceland, some 850 miles from Edinburgh.  Because of an unusual meteorological configuration, the prevailing winds sent the plume of volcanic gases southward towards Scotland.  Had the eruption taken place 60 miles further north or happened a few hours later, the plume of gases would have missed the UK entirely and would have traveled north to the Arctic region.

Icelandic volcanic eruptions have impacted air travel in Europe on a number of occasions.  This non-explosive eruption had little impact outside of its local region, but it turned out to briefly wreak havoc in Scotland.  Fortunately, this pollution event was short-lived.

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Atmospheric sulphur dioxide levels reach historic high in Scotland following Icelandic volcano eruption

Photo, posted November 17, 2021, courtesy of Catherine Poh Huay Tan via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

California renewable energy

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California has aggressively pursued the use of renewable energy, particularly solar and wind power.  Last year, renewables supplied 54% of the state’s electricity needs.  This year, California has been achieving some remarkable milestones with its renewable energy.

As of May 26th, California had produced more than 100% of its electricity demand with wind, solar, and hydropower for parts of 51 straight days and 75 out of 81 days.  On May 25th, California’s grid ran entirely on renewable energy for 10.1 straight hours and renewables provided 83% of the state’s electricity for the entire 24-hour period.  California uses more electricity than any other state apart than Texas, which uses more than half its energy for operating refineries and petrochemical plants.

Excess power in California is either exported to other states or is used to charge up the state’s growing arrays of energy storage batteries.  California has the largest grid-connected battery storage facility in the world, located in Kern County.  The facility can store nearly 3,300 megawatt-hours of energy.

The ability to produce more power than the state needs occurs during the day when the sun is shining, and when many people are not at home.  At night, demand goes up and solar power is not available.  But as the quantity of energy storage available continues to grow along with additional solar installations, California will ultimately be able to wean off of the gas-fueled power plants it predominantly uses at night.

According to some experts, California may operate entirely on renewables and battery storage as soon as 2035. 

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California exceeds 100% of energy demand with renewables over a record 30 days

Photo, posted January 11, 2016, courtesy of Jared Eberhardt via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Wind farms and land use

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Wind power has become one of the most affordable ways to generate electricity as well as being renewable and not contributing to global warming.  But there has been the perception that wind farms require a lot of land compared with fossil fuel power plants. This issue of land use has made decision-makers reluctant to invest in wind energy in many instances.

A new study by McGill University in Montreal looked at this issue and has found that land use for wind power is far more efficient than previously thought.  The study combined data from geographic information systems with machine learning models to assess land usage associated with nearly 16,000 wind turbines in the western U.S.

The study assessed the land use of 320 wind farms.  They found that wind power infrastructure (mostly the turbines themselves and the roads that lead to them) typically only uses 5% of the land area of a wind farm.  If the wind farm is sited in locations with existing infrastructure, such as on agricultural land, then it can be as much as seven times more land-efficient – meaning the amount energy produced in a given area of land impacted by the infrastructure – than a wind farm that is developed on unused land.

Previous studies of wind farm land usage assumed that all of the land where the wind farm was located was devoted to energy generation.  In reality, most of land in question is often used for other purposes, such as agriculture.

The methods developed by the researchers are potentially useable for future assessments of various energy technologies in terms of their environmental sustainability.

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Clearing the air: wind farms more land efficient than previously thought

Photo, posted September 29, 2009, courtesy of Tim Green via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

The end of coal in New England

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The last two coal-fired power plants in New England are scheduled to close by 2025 and 2028.  The New Hampshire-based plants are operated by Granite Shore Power.  The Schiller Station plant began operations in 1949 and the Merrimack Station was built in the 1960s.

Granite Shore Power has come to an agreement with the Environmental Protection Agency as part of a settlement of lawsuits by the Conservation Law Foundation and the Sierra Club.  The two power plants were the subject of a five-year legal battle waged by clean energy advocates

Granite Shore Power intends to turn both of the sites into renewable energy parks.  The plants will be converted into solar farms and battery units that can be used to store electricity generated by offshore wind turbines along the Atlantic Coast.  Granite Shore Power bought the two power plants in 2018 with the intention of transitioning the coal generation systems into less polluting operations.

The battery storage system at the Schiller Station site in Portsmouth will be named the Jacona II in honor of a self-propelled floating power barge that brought power to parts of Maine and New Hampshire between 1919 and 1930.

Coal use has dropped dramatically in the United States in recent years as natural gas and renewable sources like wind and solar have become less expensive.  As of last year, coal only produced about 17% of American electricity and its use continues to decline. 

Coal is the dirtiest fossil fuel.  In 2021, when it generated less than a quarter of the electricity produced in the US, it accounted for 59% of carbon emissions from electricity generation.

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The Last Coal-Fired Power Plants in New England Are to Close

Photo, posted October 14, 2015, courtesy of Eversource NH via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Air pollution in India

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India is one of the world’s most polluted countries.  In fact, of the 30 cities with the worst air pollution around the globe, 21 of them can be found in India. 

India’s capital city, New Delhi, is the most polluted city in the world.  Concentrations of fine particulate matter (known as PM2.5) in Delhi, which is the name of the larger city that includes the capital New Delhi, are nearly 10 times greater than the World Health Organization guidelines. 

To reduce air pollution in Delhi, officials have focused on measures within the city limits, including boosting public transportation and regulating pollution from industry. 

But according to a review carried out by the University of Surrey and regional government officials in Delhi, the city will also need the help of its neighbors to tackle its killer smog problem.  Some of the pollution plaguing Delhi comes from rural areas in the region –  from things like crop burning, wood stoves, and power plants.  The review, which was part of a paper recently published in the journal Sustainable Horizons, also recommends drafting regional air quality plans, producing smog forecasts, and creating airshed councils to help improve coordination. 

Exposure to air pollution can cause all sorts of major health problems, including asthma, respiratory inflammation, as well as  jeopardize lung function, and even promote cancer.  Long-term exposure to PM2.5 is linked to premature death.  In fact, air pollution causes an estimated 670,000 deaths every year in India. 

Since air pollution doesn’t respect boundaries or borders, solutions require collaboration and the need to focus efforts more broadly in order to achieve emissions reduction goals. 

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Delhi smog: India’s cities must look beyond their limits to clean up air pollution

Photo, posted December 27, 2019, courtesy of Ninara via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Moisture swing carbon capture

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As the world grapples with limiting the amount of carbon dioxide in the atmosphere, there is a growing need to capture the carbon dioxide that is emitted as well as preventing it from being emitted in the first place.  Carbon capture can be accomplished at the source of emissions (such as power plants) or it can be done by taking it out of the atmosphere.  The latter is called “direct air capture”.

It is not at all clear whether direct air capture can be accomplished on a scale that would really make a difference and at an acceptable cost either in dollars or energy expended.  But if it can be done that way, it would be a major tool in combatting climate change.

Direct air capture technology generally makes use of sorbent materials whose capacity to capture carbon dioxide and later release it is a function of temperature.  The process requires significant amounts of energy to release the carbon dioxide that has been captured. 

New research from Northwestern University makes use of the “moisture-swing” technique which uses materials whose ability to capture and release carbon dioxide depends on humidity rather than temperature.  While it takes some amount of energy to humidify the volume of air containing the sorbent material, it is very small compared to temperature-driven systems. 

There are many groups working with moisture-swing technology, but the Northwestern Group has identified a number of new sorbent materials with superior properties.

The fundamental questions of scalability and cost remain, but moisture-swing is a promising approach to direct air capture.  If carbon dioxide can be pulled out of the atmosphere in large volumes, it can be concentrated and stored or converted into useful products.

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Pulling carbon dioxide right out of the air

Photo, posted May 15, 2020, courtesy of James Watt via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Floating Solar And Hydropower | Earth Wise

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Installing solar panels on the surface of reservoirs is an up-and-coming trend.  The arrays of solar panels produce renewable energy while at the same time shielding significant expanses of water from the sun’s heat, thereby reducing evaporation.  The panels also help to inhibit the growth of algae.

Two recent floating solar installations are demonstrating the synergy between solar power and hydroelectric power.

The Lazer floating solar plant in France comprises over 50,000 solar panels and is capable of producing 30 MW of power.  The reservoir serves a 16.5 MW hydropower plant.  During the summer, the water from Lazer Reservoir is used primarily for crop irrigation and the solar plant supplements power generation as the reservoir water level experiences variations.  This is the first facility of its kind to be installed in France.  The company that built it – the EDF Group – had already built four floating solar power plants in Israel and the US. 

In Colombia, the Aquasol solar project is installed at the 340 MW Urrá hydropower plant.  Its 2,800 solar panels produce enough power to offset the amount of energy it takes to operate the dam.  The floating solar system is designed to withstand water-level fluctuations of up to 120 feet.

Floating solar systems can help keep power flowing when low water levels or other adverse conditions reduce hydroelectric output.  About 60% of the world’s renewable energy comes from hydropower.  Given this fact, there are countless opportunities to deploy floating solar that maximizes zero-emission energy generation as well as diversifying clean energy sources.

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Floating solar and hydropower: A match made in renewable energy heaven

Photo, posted October 25, 2010, courtesy of Martin Abegglen via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Wind And Solar Pass Coal | Earth Wise

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For the first five months of this year, wind and solar generated more electricity than coal in the United States.  This is a first.  Total renewable energy generation exceeded coal-fired power in both 2020 and 2022, but that counted hydroelectric power as one of the renewable sources.

This year, wind and solar alone generated a total of 252 terawatt-hours of energy through May compared with coal’s output of 249 terawatt-hours.  Hydropower generated an additional 117 terawatt-hours during that period.

While solar and wind power have been expanding at a rapid rate, the biggest change this year has been a precipitous drop in coal-fired generation due to a combination of low natural gas prices, a mild winter, and a series of coal plant retirements.

Coal generated almost half of the country’s electricity as recently as 2008.  Since then, coal has steadily declined as older coal plants shut down and were replaced by natural gas plants and renewable energy sources.  The coal industry had a bit of a reprieve last year when natural gas prices spiked in response to the disruptions in gas supplies in Europe due to the war in Ukraine.  The benchmark for natural gas prices – known as Henry Hub – was $8.81 in August 2022.  In May of this year, it was $2.15.  Given this trend, the demand for coal has steadily declined. 

The US has retired another 7% of the coal fleet – 14 gigawatts of capacity – since the start of 2022.  Meanwhile, power companies have added 22.5 GW of wind and solar capacity in just the past 12 months.

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In a First, Wind and Solar Generated More Power Than Coal in U.S.

Photo, posted September 20, 2016, courtesy of Bureau of Land Management via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Chatbots Are Thirsty | Earth Wise

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We hear a lot about artificial intelligence these days.  ChatGPT has found its way into education, technology, and many other aspects of life.  It and its brethren are a source of fascination, enthusiasm, and even fear.  Many of us have given queries to the bot to see what kind of results we can obtain.  But a recent study has found out something about AI systems that we probably didn’t know – they use up lots of fresh water.

According to researchers at the University of California, Riverside, running a few dozen queries on ChatGPT uses up about half a quart of fresh water from already overtaxed reservoirs.

Running artificial intelligence systems like ChatGPT relies on cloud computations done in racks of servers in warehouse-sized data processing centers.  Google’s data centers in the U.S. alone consumed nearly 3.5 billion gallons of fresh water in 2021 in order to keep their servers cool.

Data processing centers consume water in two ways.  They often draw much of their electricity from power plants that use large cooling towers that convert water into steam emitted into the atmosphere.  In addition, the servers themselves need to be cooled to keep running and are typically connected to cooling towers as well.

It isn’t going to be easy for AI systems to reduce their water use.  The study’s authors noted that people make use of AI at all hours of the day and night.  But a significant amount of AI activity is actually the training of the systems.  That could be scheduled for the cooler hours, when less water is lost to evaporation.

In an era of scarce fresh water and droughts, it is important to make AI less thirsty.

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AI programs consume large volumes of scarce water

Photo, posted May 22, 2023, courtesy of Jernej Furman via 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...)