Going by this year's rainfall performance and outlook reports issued by the meteorology department, most areas in Uganda have received poor rainfall.
Statistics show that most parts of the country have received rainfall within the near normal to below normal range throughout the first half of this year, a proof that global warming is real.
In the last two years alone, the country has experienced shortage of food, inflation, floods and general increase in temperature, which has affected the economy.
Global warming, a gradual increase in the temperature of the atmosphere, is tending to change the earth's climate permanently. The warming is largely the result of emissions of greenhouse gasses for human activities, fossil fuel combustion and changes in land use such as deforestation and agriculture as well as industrial processing.
The greenhouse effects is a phenomenon whereby certain gases (CO2 methane and the other gases) in the earth's atmosphere, absorb heat that would otherwise escape to space.
As the country feels the impacts of climate changes, the worst scenario is reported in the cattle corridor, stretching from the northern region to the southwest region.
It is reported that the cattle corridor has a fragile ecosystem that is gravely affecting agriculture, cattle keeping, health and water.
GA_googleFillSlot( "AllAfrica_Story_InsetB" );
Ms Rehema Kahigwa Akiki, a subsistence farmer of Wabigalo village, Wabinyonyi Sub-county in Nakasongola District (one of the districts that lies in the corridor), says the situation is worrying.
Ms Kahigwa, a single mother of eight, whose livelihood solely depends on farming, says bad weather has frustrated their efforts to overcome poverty.
The farmer, who grows matooke (bananas) and rears local poultry, reveals that chronic drought has gravely affected her banana plantations, diminishing her returns by more than half.
"In order to maintain this garden, I have to irrigate it daily with water I fetch from a water dam located about one and half kilometre from here," a distressed mother says.
"At times I am forced to buy water at Shs200 per 20litre jerrican to irrigate because I can't sit and look on when my garden, the only source of income, is drying up."
GA_googleFillSlot( "AllAfrica_Story_InsetC" );
To Salongo Stanley Senku, a commercial farmer of Macumu-Sasira parish in Nakasongola District, this year's first season has been a gamble. He says the change in weather patterns has prompted them to plant whenever they see some rains, which was a grave move.
"We have harvested nothing in this year's first season due to poor rain," Mr Senku who has lived on farming for over 30 years, says.
All crops he planted after receiving mild rains stunted or dried up as temperatures soared.
"This season alone, I have slashed two maize plantations, one of seven acres and another on of 10 acres after they dried up," he narrates.
Salongo Senku says Uganda's two rainy seasons, the long rain starting in March and lasting through until June and the short rains running from around October/November to December are now erratic.
GA_googleFillSlot( "AllAfrica_Story_InsetD" );
The farmers' misery, however, is echoed by the District's Production officer Sarah Nakamya, who admits that the district is in crisis.
"We have been advising farmers to diversify cattle keeping with crop farming, but what disturbs, is that people are not harvesting due to bad weather and animals have started dying," she laments. She says though they receive weather focus reports from the meteorology department, purposely to advise farmers on when to start sowing with a view of minimising losses, the practice has yielded nothing because reports are also erratic.
She says with such experiences, farmers have lost trust in them. Despite the fact that Nakasongola greatly depend on agriculture, the district has intensely destroyed its tree cover due charcoal burning.
Currently, the district is ranked among the three districts (Nakasongola, Kiboga and Apac) that lead in charcoal supply.
Meanwhile, Ms Nakamya, says the district is currently sensitising residents to abandon charcoal burning and plant more trees to restore what has been degraded. But the rate at which trees are cut doesn't match with those being planted.
Currently, deforestation in Uganda is alarming. Over 90,000 hectares of Uganda's forest cover disappear per year yet deforestation is responsible for up to 20 per cent greenhouse gases.
According to the March 1 to April 30, 2009 meteorology report, places in the Lake Basin and central, Kampala recorded 43 per cent, Namulonge 61 per cent and Kituza 67 per cent of their Long-Term Mean (LTM) rainfall, which was in the below normal range. Only Kibanda, Entebbe and Mubende recorded amounts which were within the near normal range; 102 per cent, 93 per cent and 80 per cent respectively.
Wednesday, July 1, 2009
Traffic Noise Pollution
Vehicular traffic noise pollution may be one of those everyday pollutions that we overlook, considering it to be annoying but not really detrimental to our health or well-being. In reality, traffic noise might just be killing many of us slowly, as well as causing lots of other irritations that we just can’t get away from.
Healthy human hearing is very sensitive, so to be subjected to prolonged exposure to traffic noise estimated to be in the range 50 to 95 dB (of equivalent sound level, or the energy mean sound level, to use the right jargon) can be both annoying and damaging to your hearing. The last century is the noisiest in the history of the world due to the advent of fossil fuels.
It seems every country has their own limits for what levels are considered to be non-damaging to the human ear, some say 85dB for more than 8 hours a day (which means 88dB for 4 hours, 91dB for 2 hours and 94dB for 1 hour, in terms of acoustical energy exposure). For sleeping, the World Health Organization proposes limits of 30 dB(A) constant noise and 45 dB(A) for individual noise events.
More than just hearing damage though, there is the stress of noise pollution that can lead to sleepless nights, anxiety, higher blood pressure and even increased chances of heart failure. Missing out on sleep makes people irritable and compromises the immune system, that lack of sleep might also mean a lack of concentration at school or work, which mean lower grades, lower pay rises and maybe an increase in accidents. Sleepless nights can also make partners grumpy the next day, meaning less blissful partnerships and maybe even contributing to break-ups.
I think we should all be looking forward to the arrival of electric and/or solar powered vehicles, they will be a lot quieter than today’s gasoline and diesel powered ones, so quiet in fact that governments might have to legislate that manufactures make them more noisy. The concern is that children and visually impaired people might not hear the vehicles coming when they are crossing the road or in parking lots.
Lotus, the specialist UK car manufacturer, has demonstrated a 300W externally mounted sound system on a Toyota Prius Hybrid which made engine like sounds when the vehicle was in hybrid mode but which switched-off when the internal gasoline engine came on. Hopefully the regulations won’t turn your future electric vehicle from a whispering buzz into a roaring V8, otherwise we won’t be able to look forward to quieter, more harmonious and healthier cities.
Healthy human hearing is very sensitive, so to be subjected to prolonged exposure to traffic noise estimated to be in the range 50 to 95 dB (of equivalent sound level, or the energy mean sound level, to use the right jargon) can be both annoying and damaging to your hearing. The last century is the noisiest in the history of the world due to the advent of fossil fuels.
It seems every country has their own limits for what levels are considered to be non-damaging to the human ear, some say 85dB for more than 8 hours a day (which means 88dB for 4 hours, 91dB for 2 hours and 94dB for 1 hour, in terms of acoustical energy exposure). For sleeping, the World Health Organization proposes limits of 30 dB(A) constant noise and 45 dB(A) for individual noise events.
More than just hearing damage though, there is the stress of noise pollution that can lead to sleepless nights, anxiety, higher blood pressure and even increased chances of heart failure. Missing out on sleep makes people irritable and compromises the immune system, that lack of sleep might also mean a lack of concentration at school or work, which mean lower grades, lower pay rises and maybe an increase in accidents. Sleepless nights can also make partners grumpy the next day, meaning less blissful partnerships and maybe even contributing to break-ups.
I think we should all be looking forward to the arrival of electric and/or solar powered vehicles, they will be a lot quieter than today’s gasoline and diesel powered ones, so quiet in fact that governments might have to legislate that manufactures make them more noisy. The concern is that children and visually impaired people might not hear the vehicles coming when they are crossing the road or in parking lots.
Lotus, the specialist UK car manufacturer, has demonstrated a 300W externally mounted sound system on a Toyota Prius Hybrid which made engine like sounds when the vehicle was in hybrid mode but which switched-off when the internal gasoline engine came on. Hopefully the regulations won’t turn your future electric vehicle from a whispering buzz into a roaring V8, otherwise we won’t be able to look forward to quieter, more harmonious and healthier cities.
Tuesday, June 30, 2009
Rising Acidity Levels Could Trigger Shellfish Revenue Declines, Job Losses
Changes in ocean chemistry — a consequence of increased carbon dioxide (CO2) emissions from human industrial activity — could cause U.S. shellfish revenues to drop significantly in the next 50 years, according to a new study by researchers at the Woods Hole Oceanographic Institution (WHOI).
Intensive burning of fossil fuels and deforestation over the last two centuries have increased CO2 levels in the atmosphere by almost 40 percent. The oceans have absorbed about one-third of all human-generated carbon emissions, but the buildup of CO2 in the ocean is pushing surface waters toward more acidic conditions.
This “ocean acidification” creates a corrosive environment for marine organisms such as corals, marine plankton, and shellfish that build carbonate shells or skeletons. Mollusks — including mussels and oysters, which support valuable marine fisheries — are particularly sensitive to these changes.
In a case study of U.S. commercial fishery revenues published in the June issue of Environmental Research Letters, WHOI scientists Sarah Cooley and Scott Doney calculated the possible economic effects of ocean acidification over the next 50 years using atmospheric CO2 trajectories from the Intergovernmental Panel on Climate Change and laboratory studies of acidification’s effects on shell-forming marine organisms, focusing especially on mollusks.
Mollusk sales by fishermen currently generate about $750 million per year — nearly 20 percent of total U.S. fisheries revenue. The study assumed that mollusks harvests in the U.S. would drop 10 to 25 percent in 50 years’ time as a result of increasing acidity levels, which would decrease these mollusk sales by $75 to $187 million dollars annually.
“Losses in primary revenue from commercial mollusk harvests—or the money that fisherman receive for their catch—could add up to as much as $1.4 billion by 2060,” said Cooley.
Reduced harvests of mollusks, as well as losses of predatory fish and other species that depend on mollusks for food, could lead to economic hardships for fishing communities.
“Ocean acidification will impact the millions of people that depend on seafood and other ocean resources for their livelihoods,” said Doney. “Losses of crustaceans, bivalves, their predators, and their habitat — in the case of reef-associated fish communities — would particularly injure societies that depend heavily on consumption and export of marine resources.”
Because changes in seawater chemistry are already apparent and will grow over the next few decades, Cooley and Doney suggest measures that focus on adaptation to future CO2 increases to lessen the impact on marine ecosystems, such as flexible fishery management plans and support for fishing communities.
“Limiting nutrient runoff from land helps coastal ecosystems stay healthy,” said Cooley. “Also fishing rules can be adjusted to reduce pressure on valuable species; fisheries managers may set up more marine protected areas, or they may encourage development of new fisheries.”
Intensive burning of fossil fuels and deforestation over the last two centuries have increased CO2 levels in the atmosphere by almost 40 percent. The oceans have absorbed about one-third of all human-generated carbon emissions, but the buildup of CO2 in the ocean is pushing surface waters toward more acidic conditions.
This “ocean acidification” creates a corrosive environment for marine organisms such as corals, marine plankton, and shellfish that build carbonate shells or skeletons. Mollusks — including mussels and oysters, which support valuable marine fisheries — are particularly sensitive to these changes.
In a case study of U.S. commercial fishery revenues published in the June issue of Environmental Research Letters, WHOI scientists Sarah Cooley and Scott Doney calculated the possible economic effects of ocean acidification over the next 50 years using atmospheric CO2 trajectories from the Intergovernmental Panel on Climate Change and laboratory studies of acidification’s effects on shell-forming marine organisms, focusing especially on mollusks.
Mollusk sales by fishermen currently generate about $750 million per year — nearly 20 percent of total U.S. fisheries revenue. The study assumed that mollusks harvests in the U.S. would drop 10 to 25 percent in 50 years’ time as a result of increasing acidity levels, which would decrease these mollusk sales by $75 to $187 million dollars annually.
“Losses in primary revenue from commercial mollusk harvests—or the money that fisherman receive for their catch—could add up to as much as $1.4 billion by 2060,” said Cooley.
Reduced harvests of mollusks, as well as losses of predatory fish and other species that depend on mollusks for food, could lead to economic hardships for fishing communities.
“Ocean acidification will impact the millions of people that depend on seafood and other ocean resources for their livelihoods,” said Doney. “Losses of crustaceans, bivalves, their predators, and their habitat — in the case of reef-associated fish communities — would particularly injure societies that depend heavily on consumption and export of marine resources.”
Because changes in seawater chemistry are already apparent and will grow over the next few decades, Cooley and Doney suggest measures that focus on adaptation to future CO2 increases to lessen the impact on marine ecosystems, such as flexible fishery management plans and support for fishing communities.
“Limiting nutrient runoff from land helps coastal ecosystems stay healthy,” said Cooley. “Also fishing rules can be adjusted to reduce pressure on valuable species; fisheries managers may set up more marine protected areas, or they may encourage development of new fisheries.”
Environmental Toxicologists Link Household Bacteria to Asthma
Researchers say asthma and allergy triggers may be commonly found at home. That means there are things you can do to reduce the cause of your family's symptoms.
Steven Pannkuk loves playing with his kids but he worries about their health. "I have some asthma and allergies in my genetics," he says. While genetics do play a role, environmental toxicologists say the bigger culprit may be in the carpet and other places that collect dust.
A new study indicates bacteria in household dust releases chemicals called endotoxins, which can inflame airways and trigger asthma.
Peter Thorne, an environmental toxicologist at the University of Iowa in Iowa City says, "If you think of a bacterium as an orange, the endotoxin is the material that makes up the peel. It's the outer layer. And this becomes shed from bacteria, and it's everywhere in the environment.
Researchers found the bedroom had fewer endotoxins, but it had a greater impact on a child's health. After all, that's where kids spend almost half their day. Plus, they have closer contact with the endotoxins. "Endotoxin in the home is related to higher rates of asthma," Thorne says.
There are things you and your family can do to lower the amount of endotoxins: wash your bed linens in hot water at least once a week, reduce clutter so you can clean better, purchase allergen-prevention pillow cases and mattress covers and don't eat in bed.
"I just try and be a little more conscious inside of what I can do so I can control my environment on the inside," Pannkuk tells DBIS. He is stuck with his seasonal allergies but is happy he can control environmental factors that affect his family.
Another cause of asthma in the home is pet dander. Cases of asthma tripled among newborns to 4-year-olds between 1980 and 2000.
show background -->
BACKGROUND: Bacteria lurking in household dust produces chemicals that may trigger asthma symptoms, whether a person suffers from asthma or allergies or not. The results, from the first nationwide study of toxins made by bacteria in households, indicate that it's not just the concentration of the bacteria-made toxin that is important. Other factors, such as how long and when a person is exposed to the bacterial toxin, as well as genetic factors, may contribute to the development of asthma.
THE STUDY: The nationwide study involved the analysis of more than 2,500 dust samples from 831 homes across the U.S. Results showed a strong association between the levels of toxins made by bacteria -- called endotoxins -- and the prevalence of diagnosed asthma, asthma symptoms and wheezing. People in households with higher endotoxin concentrations had higher instances of respiratory symptoms.
ABOUT ENDOTOXINS: Endotoxins are found in the cell wall of bacteria and are only released when the cell ruptures or disintegrates. Because bacteria can be found everywhere in the home, the likelihood of such a release is very high. Once released, endotoxins can cause inflammation of the airways and lead to asthma symptoms. Endotoxin levels can be reduced in the same way that allergy symptoms can be reduced: by removing dust, keeping the floors as clean as possible, keeping moisture low, repairing water damage, cleaning bed linens, and using a high-efficiency vacuum cleaner with a HEPA filter, among other actions.
ASTHMA OR ALLERGIES? Asthma is a chronic disease affecting the airways that carry air in and out of the lungs. The inside walls of the airways become inflamed (swollen) and narrower so less air can flow through the lung tissues. This in turn causes wheezing, coughing, tightness in the chest, and trouble breathing. Asthma is linked to allergies, although not everyone with asthma has allergies. People with allergies tend to react more strongly to the presence of allergens such as animal dander, dust mites, pollen or mold, as well as cigarette smoke and air pollution.
Steven Pannkuk loves playing with his kids but he worries about their health. "I have some asthma and allergies in my genetics," he says. While genetics do play a role, environmental toxicologists say the bigger culprit may be in the carpet and other places that collect dust.
A new study indicates bacteria in household dust releases chemicals called endotoxins, which can inflame airways and trigger asthma.
Peter Thorne, an environmental toxicologist at the University of Iowa in Iowa City says, "If you think of a bacterium as an orange, the endotoxin is the material that makes up the peel. It's the outer layer. And this becomes shed from bacteria, and it's everywhere in the environment.
Researchers found the bedroom had fewer endotoxins, but it had a greater impact on a child's health. After all, that's where kids spend almost half their day. Plus, they have closer contact with the endotoxins. "Endotoxin in the home is related to higher rates of asthma," Thorne says.
There are things you and your family can do to lower the amount of endotoxins: wash your bed linens in hot water at least once a week, reduce clutter so you can clean better, purchase allergen-prevention pillow cases and mattress covers and don't eat in bed.
"I just try and be a little more conscious inside of what I can do so I can control my environment on the inside," Pannkuk tells DBIS. He is stuck with his seasonal allergies but is happy he can control environmental factors that affect his family.
Another cause of asthma in the home is pet dander. Cases of asthma tripled among newborns to 4-year-olds between 1980 and 2000.
show background -->
BACKGROUND: Bacteria lurking in household dust produces chemicals that may trigger asthma symptoms, whether a person suffers from asthma or allergies or not. The results, from the first nationwide study of toxins made by bacteria in households, indicate that it's not just the concentration of the bacteria-made toxin that is important. Other factors, such as how long and when a person is exposed to the bacterial toxin, as well as genetic factors, may contribute to the development of asthma.
THE STUDY: The nationwide study involved the analysis of more than 2,500 dust samples from 831 homes across the U.S. Results showed a strong association between the levels of toxins made by bacteria -- called endotoxins -- and the prevalence of diagnosed asthma, asthma symptoms and wheezing. People in households with higher endotoxin concentrations had higher instances of respiratory symptoms.
ABOUT ENDOTOXINS: Endotoxins are found in the cell wall of bacteria and are only released when the cell ruptures or disintegrates. Because bacteria can be found everywhere in the home, the likelihood of such a release is very high. Once released, endotoxins can cause inflammation of the airways and lead to asthma symptoms. Endotoxin levels can be reduced in the same way that allergy symptoms can be reduced: by removing dust, keeping the floors as clean as possible, keeping moisture low, repairing water damage, cleaning bed linens, and using a high-efficiency vacuum cleaner with a HEPA filter, among other actions.
ASTHMA OR ALLERGIES? Asthma is a chronic disease affecting the airways that carry air in and out of the lungs. The inside walls of the airways become inflamed (swollen) and narrower so less air can flow through the lung tissues. This in turn causes wheezing, coughing, tightness in the chest, and trouble breathing. Asthma is linked to allergies, although not everyone with asthma has allergies. People with allergies tend to react more strongly to the presence of allergens such as animal dander, dust mites, pollen or mold, as well as cigarette smoke and air pollution.
Peer Pressure Plays Major Role In Environmental Behavior
People are more likely to enroll in conservation programs if their neighbors do--a tendency that should be exploited when it comes to protecting the environment, according to results of a new study.
The research, to be published in the journal Proceedings of the National Academy of Sciences (PNAS) this week, is the first to focus on the phenomenon of social norms in the context of China's conservation efforts, said scientist Jianguo "Jack" Liu of Michigan State University (MSU).
The study focused on a mammoth government initiative called Grain-to-Green that pays Chinese farmers to convert cropland back to forest.
"Much of the marginal cropland in rural communities has been converted from agriculture to forests through the Grain-to-Green Program, one of the largest 'payment for ecosystem services' programs in the world," said Alan Tessier, program director in the National Science Foundation (NSF)'s Division of Environmental Biology.
"Results of this study show that a community's social norms have substantial impacts on the sustainability of these conservation investments."
Liu's research was funded through NSF's Coupled Natural and Human Systems (CNH) Program. CNH is co-funded by three NSF Directorates: Biological Sciences; Geosciences; and Social, Economic & Behavioral Sciences.
While money is a key factor in whether people sign up for the voluntary program, peer pressure also plays a surprisingly large role, Liu said.
"That's the power of social norms," he said. "It's like recycling. If you see your neighbors doing it, you're more likely to do it."
A representative survey of households in China's Wolong Nature Reserve for giant pandas found that both government payments and social norms had "significant impacts" on citizens' intentions of re-enrolling in the Grain to Green program.
"In other words, people's re-enrollment intentions can be affected by the re-enrollment decisions of their neighbors and tend to conform to the majority," says Liu.
Xiaodong Chen, a doctoral student at MSU and lead author of the paper, said government officials should leverage these social norms along with economic and demographic trends when deciding how to support conversation programs such as Grain to Green.
"We found that, without considering the social norm factor, conservation payments may not be used efficiently," Chen said.
"But if the government considers social norms as it decides where to invest money, it could obtain more environmental benefits in communities that are supportive of these programs than in those that aren't."
Added co-author and MSU scientist Frank Lupi: "Simply by taking account of the social norms, more conservation can be obtained from limited conservation budgets."
Also contributing to the study was doctoral student Guangming He.
Funding also was provided by NASA, the National Institutes of Health, MSU's Environmental Research Initiative and the Michigan Agricultural Experiment Station.
The research, to be published in the journal Proceedings of the National Academy of Sciences (PNAS) this week, is the first to focus on the phenomenon of social norms in the context of China's conservation efforts, said scientist Jianguo "Jack" Liu of Michigan State University (MSU).
The study focused on a mammoth government initiative called Grain-to-Green that pays Chinese farmers to convert cropland back to forest.
"Much of the marginal cropland in rural communities has been converted from agriculture to forests through the Grain-to-Green Program, one of the largest 'payment for ecosystem services' programs in the world," said Alan Tessier, program director in the National Science Foundation (NSF)'s Division of Environmental Biology.
"Results of this study show that a community's social norms have substantial impacts on the sustainability of these conservation investments."
Liu's research was funded through NSF's Coupled Natural and Human Systems (CNH) Program. CNH is co-funded by three NSF Directorates: Biological Sciences; Geosciences; and Social, Economic & Behavioral Sciences.
While money is a key factor in whether people sign up for the voluntary program, peer pressure also plays a surprisingly large role, Liu said.
"That's the power of social norms," he said. "It's like recycling. If you see your neighbors doing it, you're more likely to do it."
A representative survey of households in China's Wolong Nature Reserve for giant pandas found that both government payments and social norms had "significant impacts" on citizens' intentions of re-enrolling in the Grain to Green program.
"In other words, people's re-enrollment intentions can be affected by the re-enrollment decisions of their neighbors and tend to conform to the majority," says Liu.
Xiaodong Chen, a doctoral student at MSU and lead author of the paper, said government officials should leverage these social norms along with economic and demographic trends when deciding how to support conversation programs such as Grain to Green.
"We found that, without considering the social norm factor, conservation payments may not be used efficiently," Chen said.
"But if the government considers social norms as it decides where to invest money, it could obtain more environmental benefits in communities that are supportive of these programs than in those that aren't."
Added co-author and MSU scientist Frank Lupi: "Simply by taking account of the social norms, more conservation can be obtained from limited conservation budgets."
Also contributing to the study was doctoral student Guangming He.
Funding also was provided by NASA, the National Institutes of Health, MSU's Environmental Research Initiative and the Michigan Agricultural Experiment Station.
Waste water plus bugs make hydrogen
Bacteria that feed on vinegar and waste water zapped with a shot of electricity could produce a clean hydrogen fuel to power vehicles that now run on petrol, researchers report.These so-called microbial fuel cells can turn almost any biodegradable organic material into zero-emission hydrogen gas fuel, says Professor Bruce Logan of Penn State University.This would be an environmental advantage over the current generation of hydrogen-powered cars, where the hydrogen is most commonly made from fossil fuels.Even though the cars themselves emit no greenhouse gases, the manufacture of their fuel does."This is a method of using renewable organic matter, using anything that's biodegradable and being able to generate hydrogen from that material," Logan says.In research published today in the Proceedings of the National Academy of Sciences, Logan and colleague Dr Shaoan Cheng used naturally-occurring bacteria in an electrolysis cell with acetic acid, the acid found in vinegar.The bacteria slurp up the acetic acid and release electrons and protons creating up to 0.3 volts of electricity. When a bit more electricity is added from an outside source, hydrogen gas bubbles up from the liquid.Water is the only emissionThis is far more efficient than water hydrolysis, where an electric charge is run through water to break it down into its constituent parts of oxygen and hydrogen."It uses about a 10th as much energy as water electrolysis," Logan says.That is because the bacteria do most of the work, breaking the organic material into subatomic particles, so all the electricity does is juice these particles to form hydrogen.The resulting fuel is a gas, not a liquid, but could still be used to power vehicles
This process could be used with cellulose, glucose, acetate or other volatile acids, Logan says. The only emission is water.Although it sounds futuristic, microbial fuel cell technology is available now. The researchers have filed for a patent on this work.These cells are too large to be put into cars, so the gaseous hydrogen fuel they produce must be made in a factory."You could put one of these reactors at a food processing plant and take the waste water and make hydrogen out of it," Logan says."Or you could go to a farm, where there's lot of cellulose or ... agricultural cellulosic residues, take that and make hydrogen there."This would be unlikely to work in big cities but might well be effective in rural areas."The first step is just to start using locations where we have waste waters that were spending money on treating, and turning those water treatment plants into hydrogen production plants," Logan says.
This process could be used with cellulose, glucose, acetate or other volatile acids, Logan says. The only emission is water.Although it sounds futuristic, microbial fuel cell technology is available now. The researchers have filed for a patent on this work.These cells are too large to be put into cars, so the gaseous hydrogen fuel they produce must be made in a factory."You could put one of these reactors at a food processing plant and take the waste water and make hydrogen out of it," Logan says."Or you could go to a farm, where there's lot of cellulose or ... agricultural cellulosic residues, take that and make hydrogen there."This would be unlikely to work in big cities but might well be effective in rural areas."The first step is just to start using locations where we have waste waters that were spending money on treating, and turning those water treatment plants into hydrogen production plants," Logan says.
Liquid coal for cars 'dirtier' than petrol
Some alternative vehicle fuels such as liquid coal can cause more harmful greenhouse gas emissions than petrol or diesel, scientists warn."Liquid coal, for example, can produce 80% more global warming pollution than [petrol]," says the US non-profit environmental group, the Union of Concerned Scientists.Some people have billed liquid coal, the name for petrol or diesel derived from coal, as a potential replacement to the oil on which countries rely heavily to fuel vehicles.Likewise another alternative fuel, petrol from tar sands, is estimated to have 14% more global warming potential compared with standard petrol, says the union in its latest report Biofuels: an important part of a low-carbon diet."Corn ethanol, conversely, could be either more polluting or less than [petrol], depending on how the corn is grown and the ethanol is produced," the report says.The analysis is based on replacing a fifth of all petrol used in the US with alternative fuels by 2030.If most of these alternatives consist of liquid coal, the change could pump pollution into the atmosphere equivalent to 34 million more cars on the road, the report says.But favouring cleaner "advanced biofuels" could cut harmful gases by a similar amount.The cleanest alternative, the report says, is cellulosic ethanol, made from grass or wood chips. It could cut greenhouse emissions compared with petrol by more than 85%."We need to wean ourselves off oil, but we should replace it with the cleanest alternatives possible," says study author Patricia Monahan."Let's not trade one bad habit for another."
Subscribe to:
Comments (Atom)