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New algae fuel
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Drivers could soon be filling their cars with petrol created using algae thanks to a new process that converts the organisms into crude oil in less than an hour.
Engineers at the U.S. Department of Energy's Pacific Northwest National Laboratory (PNNL) have created a chemical process that produces useful crude oil minutes after they pour in harvested algae - a verdant green paste with the consistency of pea soup.
Now a biofuels company, Utah-based Genifuel Corp., has licensed the technology and is working with an industrial partner to build a pilot plant for mass production.
In the process, recently featured in the journal Algal Research, a slurry of wet algae is pumped into the front end of a chemical reactor.
Once the system is up and running, crude oil comes out in less than an hour, along with water and a byproduct stream of material containing phosphorus that can be recycled to grow more algae.
With additional conventional refining, the crude algae oil is converted into aviation fuel, gasoline or diesel fuel.
 
And the waste water is processed further, yielding burnable gas and substances like potassium and nitrogen, which, along with the cleansed water, can also be recycled to grow more algae.
The process creates :
 
Crude oil for fuelling vehicles
In the team's experiments, generally more than 50-70  per cent of the algae's carbon is converted to energy in crude oil
 
Clean water, which can be re-used to grow more algae.
 
Fuel gas, which can be burned to make electricity or cleaned to make natural gas for vehicle fuel in the form of compressed natural gas.
 
Nutrients such as nitrogen, phosphorus, and potassium — the key nutrients for growing algae.
 
While algae has long been considered a potential source of biofuel, and several companies have produced algae-based fuels on a research scale, the fuel is projected to be expensive.
The PNNL technology harnesses algae's energy potential efficiently and incorporates a number of methods to reduce the cost of producing algae fuel.
'Cost is the big roadblock for algae-based fuel,' said Douglas Elliott, the laboratory fellow who led the PNNL team's research.
'We believe that the process we've created will help make algae biofuels much more economical.'
PNNL scientists and engineers simplified the production of crude oil from algae by combining several chemical steps into one continuous process.
The most important cost-saving step is that the process works with wet algae.
Most current processes require the algae to be dried - a process that takes a lot of energy and is expensive. The new process works with an algae slurry that contains as much as 80 to 90 per cent water.
'Not having to dry the algae is a big win in this process, that cuts the cost a great deal,' said Elliott.
'Then there are bonuses, like being able to extract usable gas from the water and then recycle the remaining water and nutrients to help grow more algae, which further reduces costs.'
While a few other groups have tested similar processes to create biofuel from wet algae, most of that work is done one batch at a time.
The PNNL system runs continuously, processing about 1.5 litres of algae slurry in the research reactor per hour.
While that doesn't seem like much, it is a step closer to the type of continuous system required for large-scale commercial production.
The system runs at around 350C (662F) at a pressure of around 3,000 pounds per square inch, combining processes known as hydrothermal liquefaction and catalytic hydrothermal gasification.
Elliott says such a high-pressure system is not easy or cheap to build, which is one drawback to the technology, though there are cost savings.
'It's a bit like using a pressure cooker, only the pressures and temperatures we use are much higher,' said Elliott.
'In a sense, we are duplicating the process in the Earth that converted algae into oil over the course of millions of years. We're just doing it much, much faster.'
Elliott has worked on hydrothermal technology for nearly 40 years, applying it to a variety of substances, including wood chips and other substances.
Because of the mix of earthy materials in his laboratory, and the constant chemical processing, he jokes that his laboratory sometimes smells 'like a mix of dirty socks, rotten eggs and wood smoke'.
James Oyler, president of Genifuel, said: 'It's a formidable challenge, to make a biofuel that is cost-competitive with established petroleum-based fuels.'
'This is a huge step in the right direction.'
 
The worse gas yet
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A new greenhouse gas that is 7,000 times more powerful than carbon dioxide at warming the Earth has been discovered by researchers in Toronto.

 The newly discovered gas, perfluorotributylamine (PFTBA), has been in use by the electrical industry since the mid-20th century.

 The chemical, that does not occur naturally, breaks all records for potential impacts on the climate, said the researchers at the University of Toronto's department of chemistry.

 "We claim that PFTBA has the highest radiative efficiency of any molecule detected in the atmosphere to date," said Angela Hong, one of the co-authors.

 The study, published in the journal Geophysical Research Letters, found PFTBA was 7,100 times more powerful at warming the Earth over a 100-year time span than CO2.

 Concentrations of PFTBA in the atmosphere are low – 0.18 parts per trillion in the Toronto area – compared to 400 parts per million for carbon dioxide. So PFTBA does not in any way displace the burning of fossil fuels such as oil and coal as the main drivers of climate change.

 Dr Drew Shindell, a climatologist at Nasa's Goddard Institute for Space Studies, said:

"This is a warning to us that this gas could have a very very large impact on climate change – if there were a lot of it. Since there is not a lot of it now, we don't have to worry about it at present, but we have to make sure it doesn't grow and become a very large contributor to global warming.".

 He said a number of recent studies had drawn attention to other potential new greenhouse gases which, like PFTBA, pack a lot of warming potential in each molecule but are not very prevalent in the atmosphere.

 Such studies were a warning against increasing uses of such compounds without first understanding their impact on climate change, he added.

 "From a climate change perspective, individually, PFTBA's atmospheric concentration does not significantly alert the phenomenon of climate change," Hong said. "Still the biggest culprit is CO2 from fossil fuel emissions."

 But PFTBA is long-lived. The Toronot researchers estimated PFTBA remains in the atmosphere for about 500 years, and unlike carbon dioxide, that is taken up by forests and oceans, there are no known natural "sinks" on Earth to absorb it.

 "It is so much less than carbon dioxide, but the important thing is on a per molecule basis, it is very very effective in interacting with heat from the Earth," she said. "Individually each molecule is able to affect the climate potentially and because its lifetime is so long it also has a long-lasting effect."

 Hong said the discovery of PFTBA and its warming potential raises questions about the climate impacts of other chemicals used in industrial processes.

 PFTBA has been in use since the mid-20th century for various applications in electrical equipment, such as transistors and capacitors. The researchers said it was unclear how widespread its use was today.

 It belongs to an entire class of chemicals used for industrial applications whose effects on the atmosphere remain unknown.

 "PFTBA is just one example of an industrial chemical that is produced but there are no policies that control its production, use or emission," Hong said. "It is not being regulated by any type of climate policy."

 
Global warming warning
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A landmark report says scientists are 95% certain that humans are the "dominant cause" of global warming since the 1950's the UN's climate panel details the physical evidence behind climate change.

On the ground, in the air, in the oceans, global warming is "unequivocal", it explained.

It adds that a pause in warming over the past 15 years is too short to reflect long-term trends.

The panel warns that continued emissions of greenhouse gases will cause further warming and changes in all aspects of the climate system. Stocker says to limit climate change will require substantial and sustained reductions of greenhouse gases. Finishes to applause.Very simple statement says Dr stocker, human influence on the climate system is clear, adopted by 110 governments by consensus not about headlines, but scientific assessment says Dr Thomas Stocker, wg1 co chair Wg1 co chair Thomas Stocker giving presentation on the new summary. Says he's slept only six hours in the last two days!

To contain these changes will require "substantial and sustained reductions of greenhouse gas emissions".

After a week of intense negotiations in the Swedish capital, the summary for policymakers on the physical science of global warming has finally been released.

The first part of an IPCC trilogy, due over the next 12 months, this dense, 36-page document is considered the most comprehensive statement on our understanding of the mechanics of a warming planet.

It states baldly that, since the 1950s, many of the observed changes in the climate system are "unprecedented over decades to millennia".

Each of the last three decades has been successively warmer at the Earth's surface, and warmer than any period since 1850, and probably warmer than any time in the past 1,400 years.

"Our assessment of the science finds that the atmosphere and ocean have warmed, the amount of snow and ice has diminished, the global mean sea level has risen and that concentrations of greenhouse gases have increased," said Qin Dahe, co-chair of IPCC working group one, who produced the report.

Speaking at a news conference in the Swedish capital, Prof Thomas Stocker, another co-chair, said that climate change "challenges the two primary resources of humans and ecosystems, land and water. In short, it threatens our planet, our only home".

Since 1950, the report's authors say, humanity is clearly responsible for more than half of the observed increase in temperatures.

But a so-called pause in the increase in temperatures in the period since 1998 is downplayed in the report. The scientists point out that this period began with a very hot El Nino year.

What is the IPCC?

In its own words, the IPCC is there "to provide the world with a clear scientific view on the current state of knowledge in climate change and its potential environmental and socio-economic impacts".

The offspring of two UN bodies, the World Meteorological Organization and the United Nations Environment Programme, it has issued four heavyweight assessment reports to date on the state of the climate.

These are commissioned by the governments of 195 countries, essentially the entire world. These reports are critical in informing the climate policies adopted by these governments.

The IPCC itself is a small organisation, run from Geneva with a full time staff of 12. All the scientists who are involved with it do so on a voluntary basis.

"Trends based on short records are very sensitive to the beginning and end dates and do not in general reflect long-term climate trends," the report says.

Prof Stocker, added: "I'm afraid there is not a lot of public literature that allows us to delve deeper at the required depth of this emerging scientific question.

"For example, there are not sufficient observations of the uptake of heat, particularly into the deep ocean, that would be one of the possible mechanisms to explain this warming hiatus."

"Likewise we have insufficient data to adequately assess the forcing over the last 10-15 years to establish a relationship between the causes of the warming."

However, the report does alter a key figure from the 2007 study. The temperature range given for a doubling of CO2 in the atmosphere, called equilibrium climate sensitivity, was 2.0C to 4.5C in that report.

In the latest document, the range has been changed to 1.5C to 4.5C. The scientists say this reflects improved understanding, better temperature records and new estimates for the factors driving up temperatures.

In the summary for policymakers, the scientists say that sea level rise will proceed at a faster rate than we have experienced over the past 40 years. Waters are expected to rise, the document says, by between 26cm (at the low end) and 82cm (at the high end), depending on the greenhouse emissions path this century.

The scientists say ocean warming dominates the increase in energy stored in the climate system, accounting for 90% of energy accumulated between 1971 and 2010.

For the future, the report states that warming is projected to continue under all scenarios and is likely to exceed 1.5C by 2100.

"We have found in our assessment analysing these model simulation[s] that global surface temperature change for the end of the 21st Century is likely to exceed 1.5 degrees Celsius relative to 1850 for all scenarios. This is a statement that is adopted by the governments of the world," Prof Stocker told reporters.

Prof Sir Brian Hoskins, from Imperial College London, "We are performing a very dangerous experiment with our planet, and I don't want my grandchildren to suffer the consequences of that experiment."

 
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