Technology

Desalination On The Rise

July 23, 2019 By EarthWise Leave a Comment

Desalination has been regarded for decades as a solution for providing fresh water to places where it is scarce. With drought becoming more common around the world – sometimes even in places where water supplies were thought to be ample – there is increasing pressure to bring new desalination plants online.

San Diego gets only 12 inches of rain a year and has no groundwater. It gets half its water from the distant Colorado River, and that source is becoming increasingly unreliable. Thus, it is no surprise that America’s largest desalination plant is in Carlsbad, about 30 miles north of San Diego. That plant provides about 10% of the fresh water needs of the region’s 3.1 million people.

There are 11 desalination plants in California, and 10 more are proposed. Desalination is huge in Saudi Arabia, Australia and Israel. Globally, more than 300 million people get their water from desalination.

But there are problems. Desalination is expensive and energy-intensive. If the process is powered by fossil fuels, it contributes to global warming. There are ecological impacts as well since it takes two gallons of sea water to make a gallon of fresh water, and the gallon left behind is extremely briny and potentially harmful to dump back into the sea. The intake systems of desalination plants are also harmful to fish and other aquatic creatures.

The cost of desalination has dropped by more than half over the last 30 years but water from it still costs about twice as much as that from other main sources. The technology is getting better and cheaper, but the industry must confront and solve serious environmental and economic problems in order for desalination to be able to meet the needs of an increasingly thirsty world.

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As Water Scarcity Increases, Desalination Plants Are on the Rise

Photo, posted January 12, 2011, courtesy of Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Bees And Plastic

July 17, 2019 By EarthWise Leave a Comment

Wild bees in Argentina have recently been found to be constructing nests entirely made of flimsy plastic material left on farms and scientists don’t know why.

In 2017 and 2018, researchers at Argentina’s National Agricultural Technology Institute built wooden, artificial nests for wild bees. These bee species burrow into nests to individually lay larvae rather than having a large hive with queens and workers. The artificial nests provide hollow openings that bees generally fill with cut leaves, twigs, and mud.

Sixty-three wooden nests were constructed and three were found lined entirely with plastic. The bees carefully cut bits of plastic in the shape and size of fingernails and arranged them in an overlapping pattern in their nests. The plastic seems to have come from plastic bags or films, which have a similar texture to the leaves bees ordinarily use to line their nests. And, in fact, leaves were readily available to the bees making use of plastic.

This is the first time that bees have been seen making nests entirely out of plastic, but for years scientists have known bees were incorporating plastic into their building materials. Research is needed to determine the potential impact plastic might have on bees, but the nest building shows that bees are highly adaptive to changing environments.

Plastic often forms a threat to wildlife in the form of microplastics that can be consumed. But there is no evidence that bees are consuming plastic. Some researchers have speculated that the plastic in bees’ nests may form a barrier against common nest issues like mold and parasites.

At this point, it is not clear whether it is a good thing or a bad thing that some bees are choosing plastic over natural materials, but it is certainly interesting.

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Wild bees are building their homes from plastic—and scientists aren’t sure why

Photo, posted December 12, 2014, courtesy of Judy Gallagher via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

A Sensor For Spoiled Milk

June 20, 2019 By EarthWise Leave a Comment

A new sensor technology developed at Washington State University may eventually make expiration dates on milk a thing of the past. The sensor essentially can ‘smell’ whether milk is still good or has gone bad.

The sensor consists of chemically coated nanoparticles that react to the gas produced when bacterial growth on milk has taken place. When such bacteria grow, they produce a volatile compound that doesn’t smell good. So, when we open a carton of milk that has begun to spoil, our noses tell us so immediately.

The new sensor does not have to be in contact with the milk. It detects the volatile gases produced by the bacteria and it changes color. So far, it has only been demonstrated in a controlled lab environment.

To really be useful, the sensor would ideally be able to show how long the milk has before it spoils. Currently, it only shows whether it is ok or already spoiled. The researchers are working on the enhanced version of the sensor.

The researchers envision working with the dairy industry to integrate the sensor technology into a milk bottle’s plastic cap so that consumers can easily see how much longer the milk will stay fresh. Current expiration dates on milk are based on best-case scenarios. They are only accurate if the milk has been stored at the correct temperature the entire time. Unfortunately, milk can inadvertently spend time above refrigerator temperature during shipment or transportation home from the store. If the new sensor technology can be successfully developed, it will be possible to know for sure whether that bottle of milk is good.

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Sensor can detect spoiled milk before opening

Photo, posted March 8, 2011, courtesy of Roxanne Ready via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Mass Timber

June 10, 2019 By EarthWise Leave a Comment

Mass timber is a type of construction typically characterized by the use of large solid wood panels for wall, floor, and roof construction. Large structural panels, posts, and beams glued under pressure or nailed together in layers, with the wood’s grain stacked perpendicular for extra strength – are prized as innovative building materials, superior to concrete and steel in many ways. Mass timber has pushed the perceived boundaries of wood construction, leading to building heights and spans that traditionally have required concrete, steel or masonry for structural support. The move to mass timber has become something of a construction revolution and many see it as a significant part of a climate change solution.

The question is just how green is mass timber construction? How sustainable is it in terms of the forest management, logging, manufacture and transportation of wood products involved?

A number of environmental groups are very skeptical. There is not yet comprehensive data on the subject. Only recently have interdisciplinary scientists begun to study the potential climate impacts of the wide use of mass timber.

Despite these questions, the mass timber industry is taking off. Demand for mass timber posts and beams has led to new sawmills opening in the U.S. Northwest and many new jobs for loggers.

The aesthetics and economics of mass timber are both very attractive compared with conventional large-scale construction materials. The real unknowns relate to the environmental impact of its widespread use. If that can take place in a sustainable and environmentally conscientious way, it would be very important in the fight against climate change. Carbon dioxide emissions from the building industry account for more than a third of global emissions, primarily from the concrete and steel industries.

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As Mass Timber Takes Off, How Green Is This New Building Material?

Photo, posted March 19, 2018, courtesy of Freres Lumber Co via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

The Energy Vault

May 28, 2019 By EarthWise Leave a Comment

A potentially transformative utility-scale energy storage technology has won a 2019 “World Changing Idea” award from Fast Company magazine. Known as the Energy Vault, the technology seeks to be the successor to the granddaddy of grid energy storage: pumped hydro.

Shifting water between higher and lower reservoirs is still basis of the vast majority of global grid storage capacity. But it is limited both by its unique location needs and by environmental regulations.

A start-up company also called Energy Vault and based in both Switzerland and Southern California has come up with an extremely creative grid storage concept. The technology consists of a six-armed crane that stacks huge concrete blocks using a currently available source of cheap and abundant grid electricity, and then drops them down to generate electricity when needed.

The system is said to operate at about 90% efficiency and can deliver long-duration storage at half the prevailing price on the market today.

A full-scale Energy Vault plant, called an Evie, would look like a 35-story crane with six arms, surrounded by thousands of manmade concrete blocks, weighing nearly 40 tons each. When charging, the plant will stack the blocks around itself higher and higher in a Babel-like tower. To discharge, the cranes drop the blocks down, generating power from the speedy descent. This configuration can deliver 4 megawatts of power and store about 35 megawatt-hours of energy.

There isn’t even a factory needed. The company would deliver a crane from a manufacturer. The crane will then assemble the blocks onsite using recycled concrete. Operation is then fully automated. The system is expected to run for 30 or 40 years.

So far there is only a one-seventh scale demo unit in Switzerland. But this is a very intriguing idea.

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Energy Vault Wins World Changing Idea Award 2019 from Fast Company for Transformative Utility-Scale Energy Storage Technology

Photo courtesy of Energy Vault.

Earth Wise is a production of WAMC Northeast Public Radio.

The World’s Largest Storage Battery

May 24, 2019 By EarthWise Leave a Comment

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

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

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

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

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

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

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

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

Earth Wise is a production of WAMC Northeast Public Radio.

Utility-Scale Solar On The Rise

May 8, 2019 By EarthWise Leave a Comment

According to research from Goldman Sachs, utility-scale solar power capacity is expected to grow by double digits globally over the next two years. The growth will be driven by expanding use of the technology in the United States, Europe, the Middle East, and China.

Solar power is the world’s fastest growing source of electricity generation and is slowly taking market share from fossil fuels like coal and natural gas. The transition is being driven by a combination of continuously lower prices for solar power and the impact of policies aimed at reducing emissions.

Utility-scale solar is defined as installations designed solely to feed electricity into the grid, in contrast to smaller-scale residential or commercial building units. There are now solar farms larger than half a gigawatt in generating capacity. According to the Goldman report, global utility-scale solar installations will reach 108 gigawatts in 2019, up 12% over the previous year, and will then grow another 10% to 119 gigawatts in 2020.

When residential and other smaller installations are included, most analysts expect global solar power capacity to soon hit 600 gigawatts. To put this in perspective, the global capacity only reached 100 gigawatts in 2012 and was actually less than 10 gigawatts in 2007.

Even more dramatic than the growth of solar installations is the reduction in solar cost, and the two are obviously closely related. Solar panel costs have dropped from around $70 per watt of electricity generated in 1980 to 36 cents per watt currently in the United States. When favorable policies both from governments and related to corporate sustainability targets are added to the mix, the booming growth in solar power is easy to understand.

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Large-scale solar power set for double-digit growth: Goldman Sachs

Photo, posted March 7, 2019, courtesy of Hedgerow Inc via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Rare Earths From Mining Waste

May 3, 2019 By EarthWise Leave a Comment

The 17 rare earth elements have become important parts of much of modern technology. Despite their name, most of these elements are relatively plentiful in the earth’s crust, but because of their geochemical properties they are typically dispersed and not often found concentrated in minerals. As a result, economically exploitable ore deposits are uncommon. There are no significant sources in the U.S.

Rare earths play important roles in high-performance magnets, electric motors in vehicles, wind turbines, microphones and speakers, and in portable electronics like cell phones. As these applications become ever larger, the need for additional sources of rare earths increases.

Researchers at Idaho National Laboratory and Rutgers University have studied a method for extracting rare-earth elements from mining waste that could greatly increase the world’s supply of these valuable materials.

It turns out that large amounts of rare earths exist in phosphogypsum, a waste product from producing phosphoric acid from phosphate rock. The U.S. alone mined 28 million tons of phosphate rock in 2017. (Phosphoric acid is used in the production of fertilizers and other products).

The researchers estimate that more than a billion tons of phosphogypsum waste sits in piles at storage sites across the U.S. alone. World-wide, about 100,000 tons of rare earth elements per year end up in phosphogypsum waste. This compares to the total current world-wide production of rare earth oxides of 126,000 tons.

The researchers studied methods for extracting the elements from the waste. A method utilizing a common environmental bacterium showed great promise.

There are concerns about residual radioactivity and other environmental issues in dealing with the waste material, but the world’s supply of rare earth elements might become much greater based on this research.

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Critical Materials: Researchers Eye Huge Supply of Rare-Earth Elements from Mining Waste

Photo, posted June 19, 2015, courtesy of David Stanley via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Making Coal To Fight Climate Change

April 19, 2019 By EarthWise Leave a Comment

Coal is the most harmful fossil fuel for the environment and, furthermore, for human health. Its use has stubbornly persisted because it is so plentiful and, therefore, cheap. As a result, a big part of efforts to fight climate change is finding a way to remove the carbon dioxide dumped into the atmosphere by the combustion of coal.

Researchers at the Royal Melbourne Institute of Technology in Australia have developed a remarkable technology that in effect reverses the process that has led to soaring CO2 levels in the atmosphere. They have found a way to pull carbon dioxide from the atmosphere and turn it into coal, after which it can be stored cheaply and safely underground.

Most previous carbon capture and storage technologies have focused on compressing carbon dioxide gas into a liquid form and then pumping it into rock formations. Such techniques are rather expensive, require lots of energy, and pose risks that the liquid CO2 could escape from its underground storage sites. More recently, research on solid metal catalysts has led to the possibility of turning CO2 into solid carbon, but most of these reactions require very high temperatures and use a lot of energy.

The new technique developed at RMIT uses a new class of catalysts based on metal alloys. With a small jolt of electricity applied at room temperature, CO2 can be converted into solid carbon – basically, coal.

If this technique can be industrialized economically, it would be like turning back the clock by taking carbon dioxide that entered the atmosphere by the combustion of coal and turning it back into coal and putting it back underground. It seems like excellent environmental justice.

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Scientists Turn Atmospheric CO2 Into Coal

Photo, posted March 16, 2015, courtesy of Will Fisher via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

A See-Through Heat Shield

January 8, 2019 By EarthWise Leave a Comment

It is estimated that air conditioners use about 6% of all the electricity produced in the United States for an annual cost of $29 billion. With rising temperatures, this expense is only going to get larger.

A significant part of the heat load in buildings arises from heat coming through windows. It turns out that for every square meter of window, about 500 watts of heat energy can be brought in by sunlight, equivalent to 5 old-fashioned light bulbs.

Researchers at MIT and the University of Hong Kong have developed a heat-rejecting film that can applied to a building’s windows that will reflect 70% of the sun’s incoming heat. The film is similar to transparent plastic wrap. It remains highly transparent at temperatures below 89 degrees Fahrenheit. Above that temperature, tiny microparticles embedded in the film shrink and the film becomes more translucent or frosted, still letting in a good amount of light, but rejecting a lot of heat.

There are already so-called smart windows on the market, similar to the electrochromic mirrors in cars that darken to prevent trailing headlights from blinding drivers. But that technology is not very effective in rejecting heat and it requires power to operate, which means you would have to pay to turn windows opaque.

Tests of the new film demonstrated its ability to reject heat and lower temperatures. The researchers estimate that if every exterior-facing window in a building were covered in the heat-rejecting film, the building’s air conditioning and energy costs could drop by 10%. Saving ten percent of tens of billions of dollars is no minor matter.

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See-through film rejects 70 percent of incoming solar heat

Photo courtesy of MIT researchers/MIT.

Earth Wise is a production of WAMC Northeast Public Radio.

Speed Breeding Of Crops

January 4, 2019 By EarthWise Leave a Comment

A technique pioneered by NASA for the purpose of growing plants extra-terrestrially is now being applied here on earth to fast-track improvements in a range of crops. The technique, known as speed breeding, has been adapted for use by British and Australian researchers on a scale ranging from vast greenhouses to desktop growth chambers.

Speed breeding uses enhanced LED lighting and day-long regimes of up to 22 hours to optimize photosynthesis and promote rapid growth of crops. By speeding up the breeding cycle of plants,it is possible, for example, to grow six generations of wheat in a year compared with two generations using traditional breeding methods.

With shortened breeding cycles, genetic improvements such as yield gain, disease resistance and climate resistance can be fast-tracked in crops such as wheat, barley, chickpeas, various Brassica species, oil seed rape and peas.

The ability to do this in compact desktop chambers permits cutting-edge research to be performed inexpensively before being scaled up to large greenhouses.

Crop development is an increasingly important activity and speed breeding is increasingly attractive in light of the opposition in some quarters to modern gene-editing techniques to create GMO crops. Speed breeding allows crop improvements via anon-GMO route.

The new technique is already being applied in Australia, which is experiencing one of the worst droughts on record. It is being used to rapidly cycle genetic improvements to make crops more drought resilient.

Generation time in most plant species is a major bottleneck in applied research programs and breeding. Speed breeding can greatly reduce this bottleneck, allowing scientists to respond more quickly to emerging diseases, the changing climate and increased demand for specific plant traits.

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JIC joins European scientists to safeguard precision breeding

Photo, posted May 8, 2016, courtesy of Yair Aronshtam via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

A Water-Based Battery

January 3, 2019 By EarthWise Leave a Comment

The transition from fossil fuel-based power plants to clean, renewable energy sources is accelerating as both wind and solar power get cheaper and increasingly become cost-competitive with traditional power sources. The biggest stumbling block both energy sources face is that they cannot always supply power on demand but require the sun to shine and the wind to blow.

Big Success From A Big Battery

January 1, 2019 By EarthWise Leave a Comment

In the fall of 2017, Tesla took on the challenge of installing a 100-megawatt battery storage system in South Australia in under 100 days, promising that the system would be free if it was not built in time. The project was actually completed in 54 days.

The system is located at the Hornsdale Wind Farm, which consists of 99 wind turbines with a generation capacity of 315 MW. The Hornsdale Power Reserve installation is the world’s largest lithium-ion battery system and, after a year of operation,has proven to be a smashing success. Estimates are that the project has reduced costs associated with stabilizing the energy grid by about $29 million. The cost of the system was about $87 million, so it is paying for itself quite rapidly. The wind farm and battery systems are owned and operated by a French renewable energy company.

The battery storage system provides a variety of different services to the electric grid. The primary motivation for it was to achieve system security and reduce the risk of blackouts and load shedding. Having the battery system in place protects the regional interconnection from tripping,which reduces the risk of separation of South Australia from the National Electricity market. The system also provides so-called ancillary services such as frequency control and other forms of electricity supply regulation.

The most significant contribution of the Hornsdale Power Reserve is that it has raised the profile of energy storage technology and demonstrated its unique capabilities. Based on the success of the system, there are now about 2,500 MWh of new storage projects announced by the public and private sectors in Australia.

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