Armored Trucks get Natural Gas & Electric Plug-in Hybrid Conversion to Reduce Emissions by 99.9% & Big Fuel Economy

Efficient Drivetrains and American Repower are partnering to convert a fleet of six armored vans to run on compressed natural gas with a plug-in hybrid.

Sourced through Scoop.it from: www.autoblog.com

>”When hauling around massive amounts of money and valuables around Southern California, security is generally a much bigger concern than fuel economy. However, the need for vehicles to become more efficient is hitting every segment, even armored vans. That’s why Efficient Drivetrains Inc. and North American Repower are teaming up to convert six of these 26,000-pound behemoths run on natural gaswith a plug-in hybrid offering additional help. The first one should be hauling riches for Sectran Security around Los Angeles in 2016.

All three companies are already positioning the upcoming conversion as a win-win solution to current issues. The armored vehicles can still do their job of hauling money around the LA area but with a claimed 99.9 percent reduction in emissions from the current diesel engines. Generally, the vans make frequent stops while at work but must stay running for security reasons. This can potentially run afoul of California’s rule not to let diesels idle more than five minutes. With this upcoming version, drivers will be able to go electrically between stops and then will use the natural gas when cruising.

This work combines the strengths of both firms working on these vehicles. North American Repower already specializes in natural gas engine management and conversions, and Efficient Drivetrains is very familiar with the world of plug-ins. The funding for the project includes a $3-million grant from the California Energy Commission, plus the same amount in private funds.”<

[…]

>”Press Release:

North American Repower and Efficient Drivetrains, Inc. to Deliver First PHEV-RNG Armored Truck
Collaboration reduces emissions by 99.9 percent

OCEANSIDE, Calif. & MILPITAS, Calif.–(BUSINESS WIRE)–Two global leaders in developing and manufacturing advanced transportation vehicles have teamed up to manufacture a first-of-its-kind fleet of Class-5 armored vehicles that combine the benefits of Renewable Natural Gas (RNG) and zero emission Plug-In Hybrid Electric Vehicle (PHEV) technology.

“We’re excited to be partnering with EDI on this breakthrough innovation”

North American Repower—California’s leading natural gas engine management and conversion technology company— and Efficient Drivetrains, Inc.—a global leader in developing high-efficiency Plug-in Hybrid Electric Vehicle solution—will convert a fleet of six 26,000 pound, Class-5 medium-duty armored vehicles operated by Sectran Security into PHEV vehicles that run on electricity and renewable natural gas—known as “Zero Emission with Range Extension” vehicles. The collaboration supports the dramatic acceleration in California toward a zero emissions environment. Today, the Sectran Security trucks make frequent stops as part of their highly congested urban routes. At each stop, the engines are kept idling for security purposes, but now risk violating California’s strict diesel idling regulations, which prohibit idling the engine for more than five minutes. With the modernized trucks, Sectran can completely eliminate engine idling by operating in all-electric mode during stop-and-go operations on urban routes and in hybrid-mode during highway operations. When complete, the vehicles possess impressive performance statistics—the demonstration trucks will enable Sectran to reduce annual diesel consumption by 31,000+ gallons, significantly reduce annual fuel costs, and reduce emissions by 99.9 percent. […]”<

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Oil Well Waste Water Used to Generate Geothermal Power

The team took off-the-shelf geothermal generators and hooked them to pipes carrying boiling waste water. They’re set to flip the switch any day. When they do, large pumps will drive the steaming water through the generators housed in 40-foot (12-meter) containers, producing electricity that could either be used on site or hooked up to power lines and sold to the electricity grid.

Sourced through Scoop.it from: www.bloomberg.com

>”Oil fracking companies seeking to improve their image and pull in a little extra cash are turning their waste water into clean geothermal power.

For every barrel of oil produced from a well, there’s another seven of water, much of it boiling hot. Instead of letting it go to waste, some companies are planning to harness that heat to make electricity they can sell to the grid.

Companies such as Continental Resources Inc. and Hungary’s MOL Group are getting ready to test systems that pump scalding-hot water through equipment that uses the heat to turn electricity-generating turbines before forcing it back underground to coax out more crude.

Though the technology has yet to be applied broadly, early results are promising. And if widely adopted, the environmental and financial benefits could be significant. Drillers in the U.S. process 25 billion gallons (95 billion liters) of water annually, enough to generate as much electricity as three coal-fired plants running around the clock — without carbon emissions.

“We can have distributed power throughout the oil patch,” said Will Gosnold, a researcher at the University of North Dakota who’s leading Continental Resources’ project well.

Geothermal power also holds out the promise of boosting frackers’ green credentials after years of criticism for being the industry’s worst polluters, says Lorne Stockman, research director at Oil Change International, an environmental organization that promotes non-fossil fuel energy.

“This is one way to make it look like the industry cares about the carbon issue,” he said. Even if steam generates less carbon than other oil field power sources, “if you’re in the business of oil and gas, you’re not part of the solution.”

Cheap Oil

Then there’s the money. With crude at less than $50 a barrel, every little bit can help lower costs. At projects like the one being tested by Continental Resources in North Dakota, a 250 kilowatt geothermal generator has the potential to contribute an extra $100,000 annually per well, according to estimates from the U.S. Energy Department.

That’s not big money and the $3.4 million cost to test the technology is still too much to apply to each of Continental’s hundreds of wells. Yet if the company can lower the costs of the technology, it will not only generate electricity it will also extend the economic life of wells, making them more profitable, said Greg Rowe, a production manager with Continental Resources. […]”<

See on Scoop.itGreen Energy Technologies & Development

Rationale Behind Construction of Site C Dam on Peace River in BC Deeply Flawed

Thirty five years ago concerned ratepayers challenged BC Hydro, the BC Utilities Commission and the Provincial government to admit that electricity conservation and small power projects were preferable to flooding the farm lands of the Peace Valley. Building another dam was not the answer then, and it is not the answer today.

Image Credit:  http://www.straight.com

Sourced through Scoop.it from: vancouver.24hrs.ca

>” Roger Bryenton & Associates, 2015 […] Conservation, plus a variety of smaller, low impact green projects can save and produce more electricity at a lower cost, with less risk, than Site C.

British Columbia has demonstrated its responsibility to live in harmony with nature when building, living and developing resources; doing “more with less”. BC Hydro is to be commended on using conservation and Independent Power producers to supply a reliable and robust power system. Ratepayers recognize these efforts and will help by saving electricity, conservation, and using small scale, “flexible” projects which can readily be adjusted to changes in demand.

Presently, we are excluding the Columbia River Treaty benefits, Alcan and Teck-Cominco power resources, and time-of- use rates which could optimize the “provincial system”. Power from the Columbia River Treaty is being sold at market rates of 3 to 4 cents/kWh rather than be included in the supply equation, where it would be worth 8 to 10 (or more) cents/kWh. Alcan and Cominco have massive dams and plants that could contribute capacity when needed, while regulations presently prevent time-of-use rates to reduce peak demand, a technique used by leading utilities worldwide.

Site C is not needed for a number of reasons:

1. Columbia River Entitlement – Both the Capacity and the Annual Energy of Site C are close to what the Columbia River entitlement offers: Site C is 1,100MW and 5,100 GWh/yr while Columbia is 1,250 MW and 4,400 GWh/yr.

2. Cost – In the original submission, the cost estimate of Site C was $5.7 Billion, or $83/MWh (8.3 cents/kWh). During hearings this increased, first to $7.9 Billion , or $114/MWh (11.4 cents/kWh).  It has increased again, to the present $8.8 billion or $126 /MWh ( 12.6 cents /kWh). By BC Hydro’s own calculations, there are literally hundreds of clean, renewable small projects that can provide capacity and energy under $114, and many more under $126/MWh.

3. Timing – Even a small amount of new power will not be needed until 2027! A massive dam takes 8 to 10 years to complete. Conservation and small power plants require a few months to 3 years to complete. Building an 1,100 MW dam if we only need 100MW is “like using a sledge hammer to crack a nut” (A. Lovins). We will not need 1100MW even by 2033 when conservation and small plants can better follow growth .

4. Capacity – Firm Capacity is only needed for a few hours every year! We do not need a huge dam to do this.

– Time of use rates. By 2020 almost 400MW of savings at $31/kW-yr would be available by significantly shifting peak loads. BC Hydro does this operationally but has refused to include it in their submitted plan.
– Pumped storage at Mica and elsewhere is economical at these prices – we do not need to flood more farmland.
– Geothermal also offers firm capacity.
– An Agreement with Alcan for some peaking, a few hours each year is feasible, but not proposed in the Site C plan.

5. Energy – Conservation, doing “more with less”, has been effective during the past 35 years, when Site C hearings originally delayed this project!

“Deep DSM” – Demand-Side Management, Option 5 of BC Hydro’s Integrated Resource Plan, can save almost 1,600MW by 2020 with energy savings of 9,600 GWh/yr. This is almost 400MW and 2000 GWh/ yr more than DSM 2. The cost is only $49/MWh; roughly half of what Site C would cost!  […]”<

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A New Era for Geothermal Energy in Alberta?

Standard thinking for decades has been that geothermal technology is too costly and inefficient to be a significant source of energy. But a growing number of experts say the time may be right for geothermal to assume a higher profile, especially in ‘perfectly situated’ Alberta.

Sourced through Scoop.it from: www.cbc.ca

>” […] The economics of renewable energy projects are improving as governments begin to introduce carbon taxes and other fees on large carbon-emitting facilities, such as coal power plants.

Geothermal power plants turn hot water into electricity. Companies drill underground for water or steam similar to the process of drilling for oil. The heat is brought to the surface and used to spin turbines. The water is then returned underground.

“I think Alberta is perfectly situated to make the technology work,” said Todd Hirsch, chief economist with ATB Financial. “All the geothermal energy experts say it is all wrong for Alberta. You have to go down so deep to get any heat. Well actually, we have experience drilling through four miles [6.4 km] worth of rock to get at other things that are valuable.”

Hirsch describes geothermal as “a perfectly green, perfectly renewable source of electricity.” He also suggests geothermal could be a boon for the province, where companies have had a knack for developing “marginal resources” such as the oilsands.

“I think geothermal energy might be one that Alberta wants to champion specifically because it doesn’t work here,” said Hirsch. “If we can make it work here in Alberta, then it is a cinch to sell the technology to the Chinese and the Germans and everyone elsewhere geothermal doesn’t work.” […]

What are the costs?

Geothermal power plants cost more money than natural gas facilities. For some perspective, consider the Neal Hot Springs plant in Oregon that was constructed in 2012 for $139 million for 22 megawatts of production.

The Shepard natural gas power plant in Calgary began operating this year with a total cost of $1.4 billion for 800 megawatts of electricity. In this comparison, the geothermal facility costs three times as much per megawatt of power.

Enbridge, a part-owner of the Neal Hot Springs plant, has said the plant saves about 159,000 tonnes per year of carbon dioxide emissions compared to a similar-sized natural gas facility, and about more than 340,000 tonnes per year compared to a coal power plant.

Coal facilities supply nearly 40 per cent of electricity in Alberta.

While the NDP government has yet to announce a specific policy, the party ran on a campaign platform in the recent election pledging to phase out coal.

Premier Rachel Notley has announced an increase to the province’s carbon pricing rules and is expected to announce significant climate change policies this year. Such changes improve the economics of renewable energy projects, such as geothermal.

“It requires a long-term vision to develop,” said Dunn. “How much do we want to invest in the future?” “<

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Geothermal Energy Projects in BC Show Economic Promise

Two potential geothermal energy projects near Pemberton could generate electricity for about seven cents a kilowatt hour — only slightly higher than the 5.8 cents to 6.1 cents a kilowatt hour cost estimate of the Site C dam project.

Sourced through Scoop.it from: www.edmontonjournal.com

>” […]  There are no geothermal energy projects operating in B.C. but the study estimated the cost per kilowatt hour for the nine sites would range from 6.9 to 7.1 cents for Pebble Creek and Meager Creek near Pemberton to 17.6 cents for Clarke Lake near Fort Nelson.

BC Hydro senior strategic technology specialist Alex Tu said some of the projects appear promising but stressed the cost estimates are still “very uncertain” and carry a lot of risk.

“Even though it says seven cents a kilowatt hour, it’s still a risky proposition,” he said. “All the geothermal in the province is still looked at as very uncertain and very high risk but if you can make the project happen, seven cents is a good price.”

Tu noted BC Hydro invested tens of millions of dollars drilling at the two Pemberton area sites in the 1970s and 1980s but could only produce enough steam for a 20-kilowatt demonstration facility that operated for 18 months.

Geothermal power facilities work by drilling into the earth and redirecting steam or hot water into turbines that convert the energy from the fluid into electricity.

Tu said Hydro has always been open to geothermal power as an alternative energy source but no geothermal projects have ever been submitted to Hydro in any of its calls for power from independent power producers.

Hydro’s standing offer program offers to pay producers $100 a megawatt hour for smaller energy projects of up to 15 megawatts. The two Pemberton area geothermal sites each have estimated capacities of 50 to 100 megawatts.

Borealis GeoPower chief geologist Craig Dunn, whose Calgary-based firm hopes to build two geothermal power plants in B.C. by 2018, said he was excited by the Kerr Wood study, which was commissioned by BC Hydro and Geoscience BC.

“I think it’s a giant step forward in recognizing that geothermal is a viable energy opportunity for the province of British Columbia,” he said.

Dunn said the drilling and turbine technology associated with geothermal power continues to improve, making that form of energy more economically viable than ever.

“As a private developer, I know that my costs are significantly less than the estimates,” he said.

Tu estimated the cost of the two proposed Borealis geothermal sites near Valemount and Terrace at about $120 to $140 a megawatt hour but Dunn said current drilling economics — with many drilling rigs now inactive due to the oil industry slowdown — could cut that estimate by 25 to 50 per cent.  […]”<

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Cover-up: Fukushima Nuclear Meltdown a Time Bomb Which Cannot be Defused

epa02660905 A handout picture provided by Air Photo Service on 30 March 2011 shows an aerial photo taken by a small unmanned drone of the damaged units of Tokyo Electric Power Co (TEPCO) Fukushima Daiichi nuclear power plant in the town of Okuma, Futaba district, Fukushima prefecture, Japan, 24 March 2011. TEPCO Chairman Tsunehisa Katsumata announced on 30 March it will be more than a few weeks to fix the Fukushima Daiichi nuclear power plant. EPA/AIR PHOTO SERVICE / HO EDITORIAL USE ONLY +++(c) dpa - Bildfunk+++

Four years after the Fukushima nuclear disaster which has caused incredible an ongoing destruction, in the meantime authorities have tried to cover up the serious consequences…

Image source: http://www.theasiasun.com/

Sourced through Scoop.it from: oilprice.com

>” […] Fukushima will likely go down in history as the biggest cover-up of the 21st Century. Governments and corporations are not leveling with citizens about the risks and dangers; similarly, truth itself, as an ethical standard, is at risk of going to shambles as the glue that holds together the trust and belief in society’s institutions. Ultimately, this is an example of how societies fail.

Tens of thousands of Fukushima residents remain in temporary housing more than four years after the horrific disaster of March 2011. Some areas on the outskirts of Fukushima have officially reopened to former residents, but many of those former residents are reluctant to return home because of widespread distrust of government claims that it is okay and safe. […]

According to Japan Times as of March 11, 2015: “There have been quite a few accidents and problems at the Fukushima plant in the past year, and we need to face the reality that they are causing anxiety and anger among people in Fukushima, as explained by Shunichi Tanaka at the Nuclear Regulation Authority. Furthermore, Mr. Tanaka said, there are numerous risks that could cause various accidents and problems.”

Even more ominously, Seiichi Mizuno, a former member of Japan’s House of Councillors (Upper House of Parliament, 1995-2001) in March 2015 said: “The biggest problem is the melt-through of reactor cores… We have groundwater contamination… The idea that the contaminated water is somehow blocked in the harbor is especially absurd. It is leaking directly into the ocean. There’s evidence of more than 40 known hotspot areas where extremely contaminated water is flowing directly into the ocean… We face huge problems with no prospect of solution.”

At Fukushima, each reactor required one million gallons of water per minute for cooling, but when the tsunami hit, the backup diesel generators were drowned. Units 1, 2, and 3 had meltdowns within days. There were four hydrogen explosions. Thereafter, the melting cores burrowed into the container vessels, maybe into the earth. […]

Following the meltdown, the Japanese government did not inform people of the ambient levels of radiation that blew back onto the island. Unfortunately and mistakenly, people fled away from the reactors to the highest radiation levels on the island at the time.

As the disaster happened, enormous levels of radiation hit Tokyo. The highest radiation detected in the Tokyo Metro area was in Saitama with cesium radiation levels detected at 919,000 becquerel (Bq) per square meter, a level almost twice as high as Chernobyl’s “permanent dead zone evacuation limit of 500,000 Bq” (source: Radiation Defense Project). For that reason, Dr. Caldicott strongly advises against travel to Japan and recommends avoiding Japanese food.

Even so, post the Fukushima disaster, Secretary of State Hillary Clinton signed an agreement with Japan that the U.S. would continue importing Japanese foodstuff. Therefore, Dr. Caldicott suggests people not vote for Hillary Clinton. One reckless dangerous precedent is enough for her. […]

Mari Yamaguchi, Associated Press (AP), June 12, 2015: “Four years after an earthquake and tsunami destroyed Japan’s Fukushima nuclear power plant, the road ahead remains riddled with unknowns… Experts have yet to pinpoint the exact location of the melted fuel inside the three reactors and study it, and still need to develop robots capable of working safely in such highly radioactive conditions. And then there’s the question of what to do with the waste… serious doubts about whether the cleanup can be completed within 40 years.” […]

According to the Smithsonian, April 30, 2015: “Birds Are in a Tailspin Four Years After Fukushima: Bird species are in sharp decline, and it is getting worse over time… Where it’s much, much hotter, it’s dead silent. You’ll see one or two birds if you’re lucky.” Developmental abnormalities of birds include cataracts, tumors, and asymmetries. Birds are spotted with strange white patches on their feathers.

Maya Moore, a former NHK news anchor, authored a book about the disaster:The Rose Garden of Fukushima (Tankobon, 2014), about the roses of Mr. Katsuhide Okada. Today, the garden has perished: “It’s just poisoned wasteland. The last time Mr. Okada actually went back there, he found baby crows that could not fly, that were blind. Mutations have begun with animals, with birds.” […] “<

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Alberta Pipeline Spills 5 Million Liters in Major Leak Near Oil Sands

Nexen Energy apologized Friday for a major leak in an Alberta pipeline that was only installed last year and said a warning system failed to detect it.

Sourced through Scoop.it from: www.news1130.com

>” […] A contractor discovered the leak Wednesday about 35 kilometres southeast of Fort McMurray, Alta. Nexen shut down the pipeline soon after, but not before some five million litres of bitumen, produced water and sand spilled into muskeg.

Nexen, which was taken over by China’s CNOOC Ltd. in 2013, says the affected area is about 16,000 square metres, mostly along the pipeline’s route. […]

John Bennett, national program director of the Sierra Club Canada Foundation, said he was worried.

“We’re always concerned when petroleum products get spilled into the environment. There’s always damage, and it’s usually permanent of some nature,” said Bennett. “It’s full of toxic elements that should not be released into the environment.” “<

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Water Quantities Used for Hydraulic Fracturing Varies According to Drilling Methods

The amount of water required to hydraulically fracture oil and gas wells varies widely across the country, according to the first national-scale analysis and map of hydraulic fracturing water usage detailed in a new USGS study accepted for publication in Water Resources Research, a journal of the American Geophysical Union.

Sourced through Scoop.it from: www.usgs.gov

>” […]  from 2000 to 2014, median annual water volume estimates for hydraulic fracturing in horizontal wells had increased from about 177,000 gallons per oil and gas well to more than 4 million gallons per oil well and 5.1 million gallons per gas well. Meanwhile, median water use in vertical and directional wells remained below 671,000 gallons per well. For comparison, an Olympic-sized swimming pool holds about 660,000 gallons.

“One of the most important things we found was that the amount of water used per well varies quite a bit, even within a single oil and gas basin,” said USGS scientist Tanya Gallegos, the study’s lead author. “This is important for land and resource managers, because a better understanding of the volumes of water injected for hydraulic fracturing could be a key to understanding the potential for some environmental impacts.”

Horizontal wells are those that are first drilled vertically or directionally (at an angle from straight down) to reach the unconventional oil or gas reservoir and then laterally along the oil or gas-bearing rock layers. This is done to increase the contact area with the reservoir rock and stimulate greater oil or gas production than could be achieved through vertical wells alone.

However, horizontal wells also generally require more water than vertical or directional wells. In fact, in 52 out of the 57 watersheds with the highest average water use for hydraulic fracturing, over 90 percent of the wells were horizontally drilled.

Although there has been an increase in the number of horizontal wells drilled since 2008, about 42 percent of new hydraulically fractured oil and gas wells completed in 2014 were still either vertical or directional. The ubiquity of the lower-water-use vertical and directional wells explains, in part, why the amount of water used per well is so variable across the United States.

The watersheds where the most water was used to hydraulically fracture wells on average coincided with parts of the following shale formations:

Eagle Ford (within watersheds located mainly in Texas)Haynesville-Bossier (within watersheds located mainly in Texas & Louisiana)Barnett (within watersheds located mainly in Texas)Fayetteville (within watersheds located in Arkansas)Woodford  (within watersheds located mainly in Oklahoma)Tuscaloosa  (within watersheds located in Louisiana & Mississippi)Marcellus & Utica (within watersheds located in parts of Ohio, Pennsylvania, West Virginia and within watersheds extending into southern New York)

Shale gas reservoirs are often hydraulically fractured using slick water, a fluid type that requires a lot of water. In contrast, tight oil formations like the Bakken (in parts of Montana and North Dakota) often use gel-based hydraulic fracturing treatment fluids, which generally contain lower amounts of water. […]”<

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Comfort is key in a passive house

duanetilden:

0620 home green  Rendering of the home Chris Weissflog, who operates the renewable energy firm Ecogen Energy, is building for his family. Among other green features, its solar panels will meet most of the 3,000-square-foot home’s heating and cooling needs as well as powering a greenhouse with an extended growing season. With story by Patrick Langston.

0620 home green Rendering of the home Chris Weissflog, who operates the renewable energy firm Ecogen Energy, is building for his family. Among other green features, its solar panels will meet most of the 3,000-square-foot home’s heating and cooling needs as well as powering a greenhouse with an extended growing season. With story by Patrick Langston.

>” […] The falling price of technology may still help us out of the quandary. The CHBA is currently developing a net zero and net zero-ready labelling program for home builders and renovators. A net zero home typically uses photovoltaic panels to produce as much energy as it consumes, generally selling excess electricity to the grid. A net zero-ready home is set up for, but does not include, the photovoltaic system.

The CHBA’s Foster says that a net zero home including photovoltaic panels now costs $50,000 to $70,000 more than a conventional home. That’s 50 per cent of the cost of just five years ago, and the price of PV panels continues to drop.

With rising energy prices, the CHBA says the extra monthly mortgage costs associated with a net zero home are now comparable to the savings in energy costs, making it net zero in more ways than one. […]”<

Originally posted on Ottawa Citizen:

Maybe your private fantasies don’t include an attic insulated to R-100, twice what’s required by the building code. Or a motion-activated gizmo that provides immediate hot water when you enter the bathroom so you don’t send thousands of gallons a year down the drain while waiting for it to warm up for a wash or shower.

But these and countless other energy-saving initiatives were on the bill during a recent tour of Ottawa-area passive homes — passive homes being ultra-energy-efficient structures — that was organized by folks either living in or building them.

So here’s the question: Since passive homes meet rigorous certification standards that, for example, mean they use 90 per cent less energy for heating and cooling than a home built to code, why aren’t we seeing these same building technologies in the production homes that most of us buy? Or are our large-scale builders actually making good strides down…

View original 1,976 more words

Airplane Contrails Boost Global Warming by Trapping Earth’s Heat Energy

The warming effects of aircraft vapor trails could be eased with fewer night flights, especially during winter, the report says.

Sourced through Scoop.it from: news.nationalgeographic.com

>” […]

Nicola Stuber, first author of the study, to be published in tomorrow’s edition of the journal Nature, suggests that contrails’ overall impact on climate change is similar in scope to that of aircrafts’ carbon dioxide (CO2) emissions over a hundred-year period.

Aircraft are believed to be responsible for 2 to 3 percent of human CO2 emissions. Like other high, thin clouds, contrails reflect sunlight back into space and cool the planet.

However, they also trap energy in Earth’s atmosphere and boost the warming effect, the study says. […]

Contrails are artificial clouds that form around the tiny aerosol particles in airplane exhaust.

They appear only in moist, very cold (less than 40ºF/4ºC) air—usually at altitudes of 5 miles (8 kilometers) or higher.

Some contrails can last for a day or longer, though they gradually disperse and begin to resemble natural clouds.

Contrails Mystery Scientists disagree about the extent of contrails’ climate impact.

“The jury is out on the impact of contrails,” said Patrick Minnis, an atmospheric scientist at NASA’s Langley Research Center in Langley, Virginia.

David Travis, a climatologist at the University of Wisconsin-Whitewater, notes that some recent studies suggest that contrails have little impact on global climate change but have a greater regional warming impact.

“I prefer to think of contrails as a regional-scale climate problem, as they are most common in certain regions of the world, such as western Europe, eastern and central U.S., and parts of eastern Asia,” he said.

“This is due to a combination of dense air traffic in these areas and favorable atmospheric conditions to support contrail persistence once they form.”

Because of their locations and short life spans, contrails are a difficult study subject.

“The greatest impediment to understanding the contrail impacts on weather and climate is the poor state of knowledge of humidity in the upper troposphere [3.8 to 9.3 miles/6 to 15 kilometers in altitude],” NASA’s Minnis said.

“Until we can measure it properly and extensively, and model it and its interaction with cirrus clouds and contrails, we will continue to have large uncertainties about the effect of contrails.”

Winter is Contrail Season

At the high altitudes favored by commercial airlines, the air is much more humid in winter, so contrails are twice as likely in that season, study co-author Stuber said.

“We also found that flights between December and February contribute half of the annual mean climate warming, even though they account for less than a quarter of annual air traffic,” she said of her U.K.-based research.

Study leader Piers Forster, of England’s University of Leeds, suggests that contrails’ current impact on the atmosphere is likely to increase as air traffic grows. […]”<

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