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The oceans are warming faster

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A new study has shown that the rate of ocean warming has more than quadrupled over the past 40 years.  The study, by researchers at the University of Reading in the UK, helps to explain why there have been unprecedented ocean temperatures in 2023 and 2024.

Global ocean temperatures hit record highs for 450 days straight in 2023 and early 2024.  Some of this unusual warmth came from the El Niño that was taking place at the time, but the rest of the increased temperature came from the sea surface warming up more quickly over the past 10 years than in previous decades.  In the late 1980s, ocean temperatures were rising at a rate of 0.06 degrees Celsius per decade.  According to the recent research, they are now increasing at 0.27 degrees per decade.

The acceleration of ocean warming is driven by growth in the Earth’s energy imbalance, meaning that more energy from the sun is being absorbed by the Earth than is escaping back into space.  This energy imbalance has roughly doubled since 2010 as a result of two factors:  increasing greenhouse gas concentrations in the atmosphere and reductions in the Earth’s albedo.

Earth’s albedo, the measure of how much sunlight is reflected back into space, has been declining since the 1970s, primarily due to the decrease in snow and ice cover, especially in the Arctic. 

The overall rate of ocean warming observed over recent decade is likely to only increase.  This underscores the urgency of reducing fossil fuel burning to avoid even more rapid temperature increases in the future.

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Ocean-surface warming four times faster now than late-1980s

Photo, posted January 18, 2007, courtesy of Alexey Krasavin via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

More eco-friendly desalination

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There are about 16,000 operational desalination plants, located across 177 countries, which generate an estimated 25 billion gallons of fresh water daily.

For every gallon of drinking water produced at a typical desalination plant, one and a half gallons of brine are produced.  Much of it is stored in ponds until the water evaporates, leaving behind solid salt or concentrated brine for further treatment.  There are various other techniques for concentrating brines, but they are energy-intensive and environmentally problematic.  The process called electrodialysis uses electrified membranes to concentrate salts. 

Water flows into many channels separated by membranes, each of which has the opposite electrical charge of its neighbors.  Positive salt ions move towards negatively charged electrodes and negative ions move toward positive electrodes.  Two streams result, one containing purified water and one containing concentrated brine.

This eliminates the need for evaporation ponds, but existing electrodialysis membranes either result in leakage of salts into the environment or are too slow, making the process impractical for large-scale use.

Researchers at the University of Michigan have developed a new kind of membrane for electrodialysis.  The new membranes don’t leak and are ten times more conductive than those on the market today which means that they can move more salt using less power.  The membranes can be customized to suit a broad range of water types, which may help make desalination a more sustainable solution to the world’s growing water crisis.

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Making desalination more eco-friendly: New membranes could help eliminate brine waste

Photo, posted February 4, 2012, courtesy of David Martinez Vicente via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Hot water in Boise

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Boise is the capital of Idaho, and the Idaho Statehouse is the only one in the United States to use geothermal heat.  Geothermal heating is possible in Boise because of fault lines that expose its groundwater to hot rocks.  The underground water supply in Boise is heated to around 170 degrees Fahrenheit.  It is the basis of the largest municipally-run geothermal system in the country.

People in Boise began using this natural resource to supply heat to buildings in the 1890s by drilling wells into aquifers that yielded hundreds of thousands of gallons of piping hot water a day.  The water heated pools and public baths, a Victorian mansion, and, eventually, hundreds of homes in what was called the Boise Warm Springs Water District.

The number of buildings that the city of Boise heats with its geothermal resource has grown more than sixfold over the past 40 years.  The water is drawn from wells in the nearby foothills and pumped into a closed-loop network of pipes that reach into buildings.  In each building, the geothermal heat is transferred to water in separate adjoining pipes that distribute the heat throughout the building.  The well water goes back to the aquifer to be heated again.

Today, there are four separately run geothermal water systems in Boise.  One is run by the city, another by the Boise Warm Springs District, and two others that serve the Capitol and Veterans Affairs Buildings.

In 2024, city officials calculated that using geothermal heat reduced annual carbon dioxide emissions by 7,000 tons, the equivalent of removing 1,500 gas-powered cars from the road each year.

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They’re in Hot Water in Idaho. Here’s Why That’s a Good Thing.

Photo, posted May 26, 2010, courtesy of Jason W via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Electric trains are healthier

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The majority of commuter trains in the U.S. are powered by diesel fuel.  This is despite the fact that electric trains are quieter, more reliable, and produce fewer greenhouse gases than diesel locomotives.  A new study has found that electric trains are healthier for passengers as well.

Caltrain carries millions of passengers a year along a 47-mile route between San Francisco and San Jose.  It is the busiest commuter rail system in the western U.S.  Over a six-week period beginning in August 2024, Caltrain retired all 29 of its diesel locomotives and replaced them with electric trains.

As the process began, an environmental engineering and environmental health professor at UC Berkeley noticed the rapid change in the air aboard the trains and decided to study its potential health impacts.  With the support of Caltrain, he installed black carbon detectors aboard the trains and tracked the improvements in air quality as old diesel locomotives were being replaced by new electric trains.

Statistical analysis of the reduction in black carbon exposure achieved by the change predicted a reduction in excess cancer deaths by 51 per million people for passengers and 330 per million people for train conductors.  EPA policy states that any exposure that increases the average individual’s cancer risk by more than one per million is considered unacceptable.

In the context of the whole U.S. where millions of people commute by rail every day, the study predicts that hundreds of cases of cancer could be prevented each year.  California has long-term plans to electrify most of its rail systems.  The study indicates that the process shouldn’t be carried over the next 25 years but rather be sped up.

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Electric trains are quieter, more reliable than diesel. New study finds they’re healthier, too.

Photo, posted September 4, 2024, courtesy of J. Kehoe via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Scrubbers to clean up shipping

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Cargo ships are significant sources of global air pollution because of their fuel oil.  Most ships burn heavy fuel oil that is loaded with sulfur, so when it is burned it produces noxious gases and fine particles that can harm human health and the environment.  The International Maritime Organization enacted a mandatory cap of 0.5% for the sulfur content of marine fuels in 2020.  Heavy fuel oil has a sulfur content of 2 to 3 percent.

Shipping companies can comply by burning low-sulfur fossil fuels or biofuels, but these are much more expensive.  The most feasible and cost-effective option is to install exhaust gas cleaning systems, known as scrubbers. 

A scrubber is a huge metal tank installed in a ship’s exhaust stack.  Seawater is sprayed from nozzles to wash the hot exhaust.  The seawater reacts with sulfur dioxide and converts it to sulfates, which are environmentally benign natural components in seawater.

A study by the National Technical University of Athens in Greece has performed a lifecycle assessment of the use of scrubbers and has found that burning heavy fuel oil with the use of scrubbers can match or even surpass the benefits of using low-sulfur fuels.

Producing low-sulfur fuel causes additional greenhouse gas and particulate matter emissions in refineries. On the other hand, scrubbers reduce sulfur dioxide emissions by 97% and dramatically reduce other pollutants as well.

The study shows the importance of incorporating lifecycle assessments into evaluation of environmental impact reduction policies.

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Study: Burning heavy fuel oil with scrubbers is the best available option for bulk maritime shipping

Photo, posted August 3, 2015, courtesy of Lotsemann via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Renewables dominate new global power

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The current administration in the United States is adversarial towards renewable energy and highly supportive of the use of fossil fuels.  Unquestionably, this will create rough waters for the clean energy industry and, unfortunately, will throw a monkey wrench into the world’s efforts to mitigate climate change.  But it cannot stop what has become a powerful global trend.

In the words of U.N. Secretary-General António Guterres: “Renewable energy is powering down the fossil fuel age.”

According to a new report from the International Renewable Energy Agency, renewables accounted for 92% of new power capacity worldwide last year.  Solar is by far the fastest-growing form of renewable power, accounting for 77% of new capacity.

In the U.S., renewables accounted for about 90% of new installed capacity in 2024.  The country added nearly 40 GW of solar power capacity as well as 5 GW of wind power.  Renewables now make up about 30% of the country’s large-scale power generating capacity.  Adding in all carbon-free electricity sources (which include nuclear power), nearly 44% of the country’s electricity was carbon-free.

Headwinds against the growth of renewable energy are getting stronger in the US, but the global trend driven by both economics and environmental concerns is powerful and will continue.  For one thing, in much of the world, solar power is simply the cheapest way to produce electricity and that is pretty difficult to ignore. Global trade wars and economic turmoil will impact renewable energy much as they will other industries, but the long-term trend is clear.

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Renewables Made Up More Than 90 Percent of New Power Installed Globally Last Year

Photo, posted November 23, 2022, courtesy of John Morton via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

A new way to recycle plastic

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Researchers at Northwestern University have developed a new method for recycling plastic that is safer, cleaner, cheaper, and more sustainable than those currently in use.  The U.S. is the world’s largest plastic polluter per capita, and we only recycle 5% of our plastics.  There is a pressing need for better technologies for processing different types of plastic waste.

The Northwestern method is designed to break down polyethylene terephthalate or PET, which is the most common type of polyester plastic.  PET plastic is used in food packaging and beverage bottles and represents 12% of total plastics used globally.  It does not break down easily and is therefore a major contributor to plastic pollution.  It mostly either ends up in landfills or, over time, degrades into tiny microplastics or nanoplastics that end up almost everywhere. 

The non-toxic, environmentally friendly, solvent-free Northwestern process first uses an inexpensive molybdenum catalyst to break apart the bonds in PET.  Then the broken plastic is exposed to ambient air.  Just from the trace amounts of moisture in air, the broken-down PET is converted into monomers, which are the building blocks of plastic.  The monomers could then be recycled back into PET products or used to make other valuable materials.

The process is fast and effective and takes just a few hours.  The catalyst is durable and recyclable, meaning it can be used over and over again.  It only works on polyesters, which means it can be used for recycling mixed plastics without sorting them since it will select only the PET from its inputs.

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Plastic recycling gets a breath of fresh air

Photo, posted August 10, 2013, courtesy of Lisa Risager via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Plastic from food waste

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Plastic waste management is a complicated business.  Most methods of recycling or breaking down plastic are costly and harmful to the environment.  The most common biodegradable alternatives – like paper straws – are less than ideal replacements.

There are many approaches to creating biodegradable plastics using feedstocks like seaweed, sugarcane, and other plant matter.  However, the resulting plastics often fall short compared with conventional petroleum-based plastics.

One type of bioplastic that is gaining popularity is polyhydroxyalkanoates, or PHA.  PHA is a plastic produced by microorganisms.  It is fully compostable or biodegradable but in other ways but looks, feels, and functions like regular plastic but without the environmental drawbacks.

PHA can be made using bacterial fermentation of a variety of feedstocks such as vegetable oils, sugars, starches, and even methane and wastewater.

Researchers at a startup from the University of Waterloo in Canada called MetaCycler BioInnovations have developed a process for producing PHA based on bacteria that has been engineered to convert waste from milk and cheese production.  This solution upcycles waste from the dairy industry into cost-effective, sustainable bio-based plastics. 

PHAs can be tailored to have a wide range of properties ranging from being rigid and tough to being quite flexible.  Therefore, they can be suitable for many applications including packaging, agricultural films, and consumer goods. 

The Waterloo technology is a way to tackle the problems of both food waste and plastic pollution with one solution.

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Turning food waste into a new bioplastic

Photo, posted December 10, 2017, courtesy of Leonard J Matthews via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

The cost of electric vehicle batteries

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The battery pack in an electric car is the most expensive part of the car. Currently, it accounts for as much as 30% of the price.  But EV batteries last a long time.  Most are guaranteed for 8-10 years and are likely to last as long as 20 years.  In practice, only 1.5% of electric cars need battery replacements for one reason or another.

The economics of EV batteries has changed dramatically over time and will continue to do so.  EV battery capacity is measured in kWh, the units you are charged for your home electricity.  An EV with a 300-mile driving range will have a battery pack that holds something like 75 kWh.

In 2008, when electric cars were just starting to enter the market again after earlier false starts, lithium-ion battery packs cost $1,355 per kWh.  When the Tesla Model S was introduced in 2012, packs were about $800. By 2019, packs broke the $200 per kWh barrier. Last year, lithium-ion battery packs reached $115 per kWh.

A combination of technology improvements and strong market competition with growing supplies is driving prices ever lower.  Industry analysts expect battery prices to drop well below $100 this year and reach about $80 next year.

The result of all of this cost reduction is that EVs will be cheaper than equivalent internal combustion vehicles, which in fact is already the case in China. Apart from cost, batteries for cars continue to improve so that the driving range of EVs will continue to increase making the cars more attractive and very practical for nearly all drivers.

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How Much Do Electric Car Batteries Cost to Replace?

Photo, posted January 22, 2019, courtesy of Steve Rainwater 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

Green grout for stabilizing buildings

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We are all familiar with the grout that is used for tiles in our homes. We are less familiar with grout that is used to stabilize the soil beneath buildings.  Grouting is a process of ground improvement by injecting materials that can fill voids and cracks, strengthen and increase the bearing capacity of soil, and reduce permeability.

Traditional grouting methods have environmental downsides.  Most often, silica-based chemical grouts are used, and they are produced through energy-intensive processes that contribute substantially to carbon dioxide emissions.  As is the case for all materials and practices of the construction industry, developing sustainable, low-emission alternatives to conventional grouting materials has become an important priority.

Researchers from the Shibaura Institute of Technology in Japan have developed an innovative new grout material called Colloidal Silica Recovered from Geothermal Fluids.  This grout material enhances soil stabilization and simultaneously reduces the environmental impact of geothermal energy harvesting.

Geothermal energy production generates large amounts of silica-rich waste fluids which creates challenges for its maintenance and disposal.  The new grout repurposes this waste material thereby transforming an industrial byproduct into a valuable construction material.

The new grout material is particularly valuable in earthquake-prone regions, where soil stabilization is essential in preventing structural damage during seismic events.  In addition, the grout’s superior water-sealing properties makes it ideal for underground construction projects like tunnels, subways, and basements.  The new grout in an important step for the construction industry’s efforts to achieve carbon neutrality.

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From Waste to Wonder: Revolutionary Green Grout for Sustainable Construction Practices

Photo, posted July 8, 2011, courtesy of MTA Construction & Development Mega Projects via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Recycling lithium-ion batteries

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Lithium-ion batteries are used to power computers and cellphones and, increasingly, vehicles.  The batteries contain lithium as well as various other valuable metals such as nickel, cobalt, copper, and manganese.  Like other batteries, lithium-ion batteries have a finite lifetime before they can no longer perform their intended function.

Recycling lithium-ion batteries to recover their critical metals is an alternative to mining those metals.  A recent study by Stanford University analyzed the environmental impact of obtaining those metals using lithium-ion battery recycling compared with mining.  They found that the recycling process is associated with less than half of the greenhouse gas emissions of conventional mining.  The process uses about one-fourth of the water and energy of mining new metals.  North America’s largest industrial-scale lithium-ion battery recycling facility is Redwood Materials, located in Nevada, which uses a clean energy mix that includes hydropower, geothermal, and solar power.

These calculated advantages are associated with recycling batteries that have been in use.  The advantages are even greater for recycling scrap:  defective material from battery manufacturers.

The advantages of recycling are dependent on the sources of electricity at the recycling plant and the availability of fresh water. 

At present, the U.S. recycles about half of its available lithium-ion batteries.  By comparison, 99% of lead-acid batteries (like those found in cars and trucks) have been recycled for decades.  As the supply of used lithium-ion batteries continues to increase, it is important for the availability of industrial-scale battery recycling to keep pace. 

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Recycling lithium-ion batteries delivers significant environmental benefits

Photo, posted May 7, 2020, courtesy of Mark Vletter via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

The green grab for land

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Solar and wind farms are spreading rapidly around the world.  Many economists believe that solar power has crossed the threshold where it is generally cheaper than other ways to make electricity and will become the dominant energy source in the next couple of decades.  As a result, both solar and wind farms are gobbling up more and more land around the world.  Estimates are that they will take up around 30,000 square miles by mid-century.

One concern is whether we are entering an era of trading food for energy.  Land conflicts seem inevitable since solar power operates best in unshaded areas with gentle winds and moderate temperatures, which are the same conditions favored by many crops.

China is installing more solar farms than the rest of the world combined.  Many of these are in the Gobi Desert, where there is no competing need for the land.  But some are in eastern China, in densely populated grain-growing areas.

There are a number of strategies that reduce the impact of solar farms on land use.  One approach is to put them on old industrial or brownfield sites that are otherwise unusable.  Another is floatovoltaics:  putting solar panels on the surface of lakes and reservoirs.  And then there is agrivoltaics, where solar panels are installed above crop fields or where livestock graze between or even beneath solar arrays.  China has more than 500 agrivoltaic projects that incorporate crops, livestock, aquafarming, greenhouses, and even tea plantations.

Green energy has both environmental and economic benefits to offer, but it must conserve nature and not excessively grab land needed for people, wildlife, and ecosystems.

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‘Green Grab’: Solar and Wind Boom Sparks Conflicts on Land Use

Photo, posted May 25, 2011, courtesy of Michael Mees via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Are today’s refrigerants safe?

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Refrigeration is based on heat transfer mediums that absorb heat from the area being cooled and transfer it to the outside environment.

The earliest refrigerants were dangerous substances like ammonia.  In the 1930s, chlorofluorocarbons (CFCs) like Freon became the standard refrigerant for use in refrigeration systems and even in aerosol cans.  When these substances were found to be depleting the earth’s ozone layer, the Montreal Protocol dictated their phaseout and by the mid-1990s, CFCs were largely replaced by hydrofluorocarbons (HFCs).

HFCs don’t deplete the ozone layer, but they were eventually determined to be potent greenhouse gases, thousands of times more planet-warming than carbon dioxide.   As a result, the global phaseout of HFCs began in 2016, and have been increasingly replaced by hydrofluoroolefins (HFOs), which are considered a more environmentally-friendly alternative to all their predecessors.

Trying to not be surprised by additional unpleasant discoveries about refrigerants, researchers are studying the potential environmental impacts of HFOs.  Researchers at the University of New South Wales in Australia have found that HFOs can break down in the atmosphere and that some small amounts of the resultant products are in fact fluoroforms, which are the HFC with the greatest global warming potential and can stay in the atmosphere for up to 200 years.

That only a small amount of HFC gets into the atmosphere is good, but nevertheless it reveals that the consequences of replacing widely-used chemicals are not a simple matter to determine.

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Are our refrigerants safe? The lingering questions about the chemicals keeping us cool

Photo, posted July 19, 2021, courtesy of Vernon Air Conditioning via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

A record year for solar and batteries

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According to a recent forecast from the U.S. Energy Information Administration, solar panels and batteries will account for more than 80% of new power capacity installed in the U.S. this year.  The record growth of these technologies is hastening the decline of coal power in this country.

Solar power alone will account for more than half of the country’s new power capacity and most of it will be in Texas and California.

Wind power is expected to provide only 12% of new capacity this year.  Wind is facing rising costs, lengthy permitting, public backlash, and clear opposition from the Trump administration which is determined to stifle its growth.

As renewable energy grows, coal power continues to decline.  The U.S. will retire twice as much coal power this year as it did last year, closing about 5% of the country’s capacity.  Not only are older coal plants shutting down; the remaining plants are generating less power.

One of the most significant changes in technology over the last few decades has been the massive drop in the cost of clean energy.  Solar photovoltaic costs have fallen by 90% in the past decade, onshore wind by 70%, and batteries by more than 90%.  The connection between cost reduction and volume has been very strong:  costs of these technologies have fallen by around 20% every time global cumulative capacity doubles.   Over the past 40 years, solar power has transformed from one of the most expensive electricity sources to the cheapest in many countries.  That trend is likely to continue.  Setting politics aside, market forces generally are the strongest driver.

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U.S. Solar and Batteries Headed for Record Year

Photo, posted December 16, 2024, courtesy of Bureau of Land Management California via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Clean energy in New York

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The New York State Energy Research and Development Authority – NYSERDA – recently issued a report on clean energy progress in the state during 2024.  The report highlighted continued and increased growth in heat pumps, electric vehicles, and solar energy.

Heat pumps, which provide both heating and cooling, have outsold gas furnaces countrywide for three straight years.  Air source heat pumps outsold gas furnaces by 37%.  This does not include ground source heat pumps, also known as geothermal heat pumps. New York offers Clean Heat rebates to offset the cost of installing heat pumps.

2024 was a good year for electric vehicles in New York with 90,221 new registrations.  More than 60 car models are eligible for New York’s Drive Clean state rebates.

New York achieved its Climate Act goal of having 6,000 MW of distributed solar power in October.  The state is expected to have more than 10,000 MW of distributed solar by 2030.

Nationwide, solar energy represented 64% of all the new electricity generation capacity installed in 2024, up from 55.5% in 2023.  Utility-scale solar generation in the lower 48 states was 36% higher in the summer of 2024 than in summer 2023.

NYSERDA’s report points out that converting to clean energy technologies can bring multiple benefits that include energy efficiency, cost savings, and reduced greenhouse gas emissions and air pollution.

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Heat Pumps, Electric Vehicles, and Solar Scale Up Through 2024

Photo, posted April 6, 2017, courtesy of Stephen Yang / The Solutions Project via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Polar bear population decline

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Researchers from the University of Toronto have directly linked the population decline in polar bears living in Canada’s Western Hudson Bay to climate change.  Between 1979 and 2021, the polar bear population in this region has declined by nearly 50%.

The monitoring data over this period shows that the average size of polar bears has declined, the size of cub litters has dropped, and cub survival rates are reduced.

The primary factor is the declining amount and duration of sea ice.  When there is less ice, bears have less feeding time and less energy overall.  The loss of sea ice means that bears spend less time hunting seals and more time fasting on land.  The lack of food leads to reduced reproduction, cub survival, and, ultimately, population decline. 

The average body mass of adult females has dropped by 86 pounds and of cubs by 47 pounds.  With shorter hunting periods and less food, mothers produce less milk.  Not only have cub litter sizes dropped over the monitoring period, but mothers are keeping their cubs longer because they are not strong enough to live on their own.  The bottom line is that the survival of cubs directly impacts the survival of the population.

Western Hudson Bay is considered to be a bellwether for polar bear populations globally.  It is one of the southernmost populations of polar bears and it has been monitored for a long time.  With the Arctic warming at a rate four times faster than the global average, polar bear populations in other Arctic regions are likely to be experiencing similar declines. 

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Polar bear population decline the direct result of extended ‘energy deficit’ due to lack of food

Photo, posted October 23, 2015, courtesy of Anita Ritenour via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Wave energy in LA

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Ocean waves form as wind blows over the surface of open water.  Globally, waves contain tremendous amounts of energy.  Theoretically, the energy generating potential of waves off the coasts of the U.S. would meet more than 60% of the country’s electricity needs.  There are a variety of methods and technologies for tapping into this energy source, but none have reached the point of commercial adoption to date.  There are many problems that remain to be solved.

Eco Wave Power, a wave energy company, announced that it has received the necessary permit from the U.S. Army Corps of Engineers to operate the first onshore wave energy installation in the United States.  The installation will be at the Port of Los Angeles at the facilities of AltaSea, a public-private ocean institute that conducts research on food and energy supply, climate change, and ocean exploration.

The system will utilize eight of Eco Wave Power’s energy floaters that will be installed on the piles of an existing concrete wharf structure on Municipal Pier One.  The system will also include an energy conversion unit enclosed in two shipping containers and connected to the floaters.  The installation is expected to be completed by the end of the first quarter of this year.

Floaters draw energy from waves by using their rising and falling motion to generate electricity. The bobbing motion of the floaters compresses and decompresses hydraulic pistons.  These transmit hydraulic fluid into land-based accumulators that build up pressure.  The pressure rotates a hydraulic motor, which then operates a generator, producing electricity.

The project is a collaboration on the development of wave energy in the Port of Los Angeles between Eco Wave Power and Shell Marine Renewable Program.

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Eco Wave Power secures final USACE permit for its first U.S. wave energy project

Photo courtesy of Eco Wave Power.

Earth Wise is a production of WAMC Northeast Public Radio

Making hydrogen using bioengineering

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Hydrogen has great potential for helping society to reach net-zero emissions.  The problem is that the most economical and established production methods for hydrogen depend heavily on fossil fuels and result in roughly a dozen kilograms of carbon dioxide emissions for every kilogram of hydrogen produced.

The carbon-free way to produce hydrogen is by splitting water into its component elements.  This process generally requires the use of catalysts and lots of energy.

Researchers at the University of Oxford are developing a synthetic biology approach to the production of so-called green hydrogen.  The idea is to replace expensive, exotic metal-based catalysts with a highly-efficient, stable, and cost-effective catalyst based on genetically-engineered bacteria.

There are specific microorganisms that can naturally induce the chemical reaction that reduces protons to hydrogen by the use of hydrogenase enzymes.  While these reactions do occur naturally, they are limited to low hydrogen yields.

The Oxford researchers genetically engineered the bacterium Shewanella oneidensis by inserting a light activated electron pump called Gloeobacter rhodopsin as well as adding nanoparticles of graphene oxide and ferric sulfate.  All of this tinkering with the bacterium resulted in a ten-fold increase in hydrogen yield.

The researchers believe that their system, based entirely on biological methods rather than traditional chemical approaches, could be scaled up to produce ‘artificial leaves’ that, when exposed to sunlight, would immediately begin producing hydrogen.  The Oxford work was published last summer in the Proceedings of the National Academy of Science.

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A green fuels breakthrough: bio-engineering bacteria to become ‘hydrogen nanoreactors’

Photo, posted July 27, 2016, courtesy of Blondinrikard Froberg via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

A new way to help purify water

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Engineers at the University of Michigan and Rice University have developed a new technology for removing boron from seawater, an important step in turning seawater into safe drinking water.

Boron is a natural component of seawater that remains a toxic contaminant in drinking water after conventional filters remove salts from seawater.  The boron levels in seawater are about twice as high as the World Health Organization’s most lenient limits for safe drinking water and 5 to 12 times higher than what many agricultural plants can tolerate.

Boron passes through the reverse osmosis membranes used in desalination plants in the form of boric acid.  To remove it, the desalination plants normally add a base to the treated water that causes the boric acid to become negatively charged.  An additional membrane then removes the charged boron, and an acid is then added to neutralize the water.  All of this is expensive and complicated.

The new technology uses electrodes that remove boron by trapping it inside pores studded with oxygen-containing structures that bind with boron but let other ions pass through.  Capturing boron with electrodes enables treatment plants to avoid the need for a second stage of reverse osmosis.

Global desalination capacity reached 95 million cubic meters a day in 2019.  The new membranes could save nearly $7 billion a year.  Such savings could make seawater a more accessible source of drinking water for a thirsty world.  Freshwater supplies are expected to meet only 40% of the world’s demand by 2030.

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New water purification technology helps turn seawater into drinking water without tons of chemicals

Photo, posted August 21, 2018, courtesy of Alachua County 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...)