New York Times article - biopolymers
April 9, 2008
Harnessing Biology, and Avoiding Oil, for Chemical Goods
By YUDHIJIT BHATTACHARJEE
THE next time you stop at a gas station, wincing at the $3.50-a-gallon price and bemoaning society’s dependence on petroleum, take a step back and look inside your car.
Much of what you see in there comes from petroleum, too: the plastic dashboard, the foam in the seats. More than a tenth of the world’s oil is spent not on powering engines but as a feedstock for making chemicals that enrich many goods — from cosmetics to cleaners and fabric to automobile parts.
In recent years, this unsettling fact has motivated academic researchers and corporations to find ways to make bulk chemicals from renewable sources like corn and switchgrass. The effort to tap biomass for chemicals runs parallel to the higher-stakes research aimed at developing biofuels. Researchers hope that the two will come together soon to help replace petroleum refineries with biorefineries.
“As petroleum prices go up and climate change becomes a serious concern, the economy will have no choice but to switch to a chemical base derived from plant materials,” said Dr. Richard Gross, director of the Center for Biocatalysis and Bioprocessing of Macromolecules at Polytechnic University in Brooklyn.
The chemical industry is beginning to make that transition, at least for a few products. One success story is a method developed by DuPont, with Genencor, to ferment corn sugar into a substance called propanediol. Using propanediol as a starting point, DuPont has created a new polymer it calls Cerenol, which it substitutes for petroleum-sourced ingredients in products like auto paints.
Similarly, the biotech giant Cargill has begun manufacturing a polymer from vegetable oils that is used in polyurethane foams, which is found in beddings, furniture and car-seat headrests. Cargill says that using the polymer does more than save crude oil and reduce carbon emissions: the foam it produces has a more uniform density and load-bearing capacity.
Researchers say these products are a good beginning, but that new cost-effective processes are needed before biorefineries can replace all petroleum-based chemicals. Many of the solutions, they say, could come from novel ways of harnessing biology.
That’s what John Frost and Karen Draths, a husband-and-wife team of chemists, showed in the late 1990s when they engineered micro-organisms that could convert glucose into aromatic alcohols — compounds traditionally produced from a petroleum product and used to make plastics.
Dr. Frost said that the research had been inspired by his fascination with microbes as a child, when his father, a dentist, described the work of patients who happened to be chemists. “I thought this was pretty cool stuff,” he said.
Dr. Frost and Dr. Draths, who left their jobs as professors at Michigan State University in December 2006 to start Draths Corporation, have more recently developed a microbial process for making phloroglucinol, a chemical to replace formaldehyde, a carcinogen, in adhesive resins. The company is also commercializing a way to make nylon entirely from renewable feedstocks like starch and cellulose.
“In this approach,” Dr. Frost said, “what was last growing season’s carbon dioxide is this quarter’s carbon used for the manufacture of chemicals and polymers.”
To make biobased manufacturing economically appealing, researchers are also determining ways to reduce the energy costs of transforming hydrocarbon building blocks like sugars and alcohols obtained from biomass into polymers. Dr. Gross and his colleagues at Polytechnic University have been using enzymes for that goal — making, among other things, a biodegradable polyester coating.
Some researchers are exploring renewable feedstocks as a source for novel materials, which could provide another economic incentive to companies to pursue biobased chemical production.
Dr. George John, a chemist at the City College of New York, and others, for example, have designed a polymer gel for drug ingestion using a byproduct of the fruit industry as a starting point. By adding an enzyme to the gel, which breaks it down over a few hours, the researchers can control the release of the drug after it is swallowed.
More players are expected to enter the field as rising oil prices force countries to increase production of biodiesel, providing a bigger supply of the byproduct glycerol.
“It could prove to be a very valuable commodity,” said Keith Simons, a chemist who consults for the Glycerol Challenge, a project started by a group of British companies and universities. The $3.6 million-a-year effort is aimed at developing catalysts and other technologies that will use glycerol as a feedstock “for making various downstream chemicals,” Mr. Simons said.
The payoffs from developing biobased chemicals could be huge and unexpected, said Dr. John Pierce, DuPont’s vice president for applied biosciences-technology. He pointed to DuPont’s synthesis of propanediol, which was pushed along by the company’s goal to use the chemical to make Sorona, a stain-resistant textile that does not lose color easily.
Soon DuPont scientists realized that bioderived propanediol could also be used as an ingredient in cosmetics and products for de-icing aircraft. The high-end grades that are now used in cosmetics are less irritating than traditional molecules, Dr. Pierce said, and the industrial grade used in de-icing products is biodegradable, which makes it better than other options.
“It looks like we found a bit of a gold vein,” he said.
New York Times article - energy efficient jet engines
April 9, 2008
A Cleaner, Leaner Jet Age Has Arrived
By MATTHEW L. WALD
JET engines are now so reliable that a pilot can go an entire career without seeing one fail. Autopilots are so good that some airlines have set up their cockpits to emit a loud beep every few minutes, to make sure the crew is still awake. And navigation is so accurate that landings can be timed to the second.
So what’s left to worry about in aviation?
In a word, fuel.
Jet fuel is now the largest expense for most airlines, and for American carriers each penny increase in price per gallon costs nearly $200 million a year. The industry is also becoming increasingly nervous about what happens when that fuel is burned. Aviation is responsible for about 2 percent of global emissions of greenhouse gases, and that share will rise as air travel continues to grow.
So the industry is scrambling to build greener airplanes — to save weight and improve engine efficiency, with an eye toward reducing operating costs and emissions.
In the short term, a revolution in jet engines is about to occur, with radically different designs that use gears to cut fuel consumption, noise and pollutants. And those new engines will power planes built more and more with carbon composite materials, which are lighter and may also be safer than the aluminum they replace.
In the longer term, the fuel itself may change; scientists are looking for an aviation version of ethanol, something that can be made from plants rather than petroleum.
The newest aircraft will also swap out many of the conventional hydraulic systems that control flaps, slats and other parts and replace them with electric motors, saving weight. In addition, new aircraft will use motors to pressurize the cabin for the same reason.
The geared jet engine will enter commercial airline service around 2013, if all goes well. Here’s how it works:
In a conventional engine, a big fan sucks air into a combustion chamber, where it is compressed, mixed with fuel and ignited. The expanding gas then blows out the back of the engine, producing thrust that pushes the plane forward.
But before the gas exits, it turns a second set of blades, which is mechanically connected to the fan in the front, to make it turn.
The problem, though, is that in current designs the two turn at the same number of revolutions per minute. But the fan in front is bigger, so the blade tips move so fast they are noisy and inefficient.
Pratt & Whitney, the engine company based in East Hartford, Conn., is testing an engine with gears arranged so that the fan in front turns at just one-third the speed of the blades in back. The innovation allows the use of a very big fan in the front, which will move more air at a slightly slower speed. “You can either make thrust by moving more air, or taking air and putting more fuel in it, to accelerate the air,” said Robert J. Saia, vice president of Pratt for new engine models. The geared turbofan does the former, he said. In addition, he said, with air moving more slowly, fewer internal parts are needed, and an engine that will produce 15,000 pounds of thrust will weigh about 500 pounds less than a conventional engine of the same power.
Mitsubishi has selected the engine for its new regional jet, and All Nippon Airways has agreed to buy 15 of them. Bombardier, in Montreal, has listed the geared turbofan as a choice for a new line of regional jets it will build.
Those new regional jets and other new planes will also use more composites. Boeing’s new 787, expected to enter service next year, will be 50 percent composites, by weight, compared with just 12 percent in its last new airplane, the 777, which was certified in 1995.
Composites have been around for years, and for aircraft are usually handmade. At the factory, the process starts with sheets of carbon fibers. In conventional manufacture, workers use shears to cut the sheets to the desired shape, layering them in a mold. Then the mold is put in an oven, and a resin, impregnated in the fibers, binds them together.
Boeing looked at that process and decided against it. “We knew that from a cost standpoint, if you had to lay down 100,000 pounds of composite material by hand, it would be very expensive,” said Tom Cogan, chief project engineer of the 787. But it has found a way to spread the carbon fiber on frames with a machine.
Carbon fiber has a weight advantage of about 20 percent over aluminum, although Boeing gave back a little bit of the gain by putting in bigger windows. The stronger composite frame of the plane makes the change possible.
Using composites to improve passenger comfort is a trend in aviation. Companies building private jets have switched to composites but used the weight advantage to build a bigger plane, rather than a plane of the same size with a lighter weight.
Corrosion is a problem on aluminum airplanes, because they pick up moist air on the ground, and the water condenses on the metal as the plane cools in the upper atmosphere. But composites do not rust, and they are not subject to metal fatigue, although they are subject to other deterioration. Still, Boeing expects planes made with more composites to have lower maintenance costs, as well as lower weight.
The 787 has another innovation that is becoming common in new designs: electric motors instead of hydraulic pumps. At Honeywell, a major manufacturer of aircraft parts, Robert H. Smith, vice president of advanced technology, described systems that will run on electricity as opposed to hydraulic fluid, as is the case today.
Among examples he cited are the brakes on a 787 and the thrust reversers on the Airbus A380. The thrust reversers are mechanical parts that slide into position to reverse the direction of the jet engine’s blast, used by pilots when they are landing. Some pneumatic systems are also being replaced; for example, the system that keeps the wings free of ice on conventional jets does so by squeezing hot air, borrowed from the jet engine, through holes in the wing. But on the 787, that work will be done by electricity. The cabin atmosphere will be pressurized by an electric pump.
Electricity is “safer, lighter and greener,” Mr. Smith said. Hydraulic fluid is flammable, and the lines that carry it are big and heavy, among other disadvantages. He added, “The technology curve is such that electric systems fundamentally have a better efficiency associated with them.” In other words, all the energy must eventually come from a jet engine, but using the engine to make electricity to apply the brakes or move a flight-control service requires less fuel than using the engine to compress air or fluid to do the same job.
The 777, a mid-1990s design, can generate up to 270 kilowatts of electricity, enough to run a small neighborhood of houses. The 787, he said, would make five times as much, 1.35 megawatts.
The long-term change, though, may come in the fuel itself. For example, the Institute for Air Science at Baylor University ran a 60-hour test of a turboprop airplane, a twin-engine King Air, with one engine flying on a mixture of 80 percent jet fuel and 20 percent biodiesel, and the other on straight jet fuel. Whenever the plane landed, it was obvious which engine was using the mixture because it had much less soot on its cowl, said Grazia Zanin, the director of renewable aviation fuels development at Baylor.
Biodiesel can be made from soybeans or other biological sources, with much less carbon dioxide output per gallon. But “we don’t think biodiesel is the answer,” she said, partly because it does not function well at the extremely cold temperatures that jets must endure at high altitudes.
Her institute has had better luck flying piston-driven planes on ethanol. That can save money on fuel and reduces the need for engine overhauls, she said. But relatively little flying is done in piston-driven planes.
The industry will have to find some solution, Ms. Zanin said, because as carbon output becomes a major concern, “commercial aviation as we know it today is not going to survive.”
New York Time article - development and energy
April 9, 2008
Money for India’s ‘Ultra Mega’ Coal Plants Approved
By Andrew C. Revkin
India electricity appetite is exploding.
The troubling tension between propelling prosperity and limiting climate risks in a world still wedded to fossil fuels is on full display this week. India’s Tata Power group just gained important financial backing from the International Finance Corporation, a branch of the World Bank, for its planned $4 billion, 4-billion watt “Ultra Mega” coal-burning power plant complex in Gujarat state.
The I.F.C., along with the Asian Development Bank, Korea, and other backers, sees the need to bring electricity to one of the world’s poorest regions as more pressing than limiting carbon dioxide from fuel burning. The plants will emit about 23 million tons of carbon dioxide a year, according to the I.F.C., but using technology that is 40 percent more efficient at turning coal into kilowatt-hours than the average for India.
The decision powerfully illustrates one of the most inconvenient facets of the world’s intertwined climate and energy challenges — that more than two billion people still lack any viable energy choices, let alone green ones.
As Michael Wines reported last year, the 700 million people of sub-Saharan Africa outside of South Africa have access to the same amount of electricity used by the 38 million people of Poland.
And the fastest-growing population on Earth is the middle class, which — whether in India or Indiana — revolves around access to electricity and mobility. (Tata Power is part of the same conglomerate that is poised to sell millions of $2,500 Nano sedans to the expanding Indian middle class.)
Here’s how the World Bank framed the issues in the I.F.C. news release on the $450 million loan for the Tata power project:
[B]etter access to energy services and higher energy use by developing countries are fundamental to the development goals of the Bank Group and our client countries. The Bank Group is working to balance these energy needs with concerns about climate change.
Within this framework, I.F.C. is prioritizing investments in renewable energy around the world: it is tripling its renewable energy and energy efficiency investments over the next three years, supporting improvements in energy efficiency through financial intermediaries, and helping increase efficiencies in transmission and distribution. With fossil fuels likely to remain a key contributor to the world’s electricity needs, I.F.C. intends to support only highly efficient coal-fired projects, such as Tata Mundra, that have a relatively lower carbon footprint than existing coal plants.
India faces power shortages that leave more than 400 million people without access to electricity, mainly in poor rural areas. The country needs to expand generation capacity by 160,000 megawatts over the next decade, and this new project helps address this gap.
Even as former Vice President Al Gore and NASA climate scientist James E. Hansen call for a freeze on new coal-plant construction in the United States unless the emissions can be captured, the reality of decades of coal burning is unfolding.
And, as we’ve written here repeatedly, experts say the world has barely begun to engage in the research and testing required to determine whether it’ll be possible to capture and bury carbon dioxide at the rate of billions of tons a year.
L. Hunter Lovins and others swear that India and China need not follow the Western norm of building prosperity on black rock and petroleum, noting the embedded subsidies in old energy habits and ample opportunities to curb energy use at a profit. But inertia appears to be their enemy. And how to blunt it remains an unanswered question.
Just one indicator of the direction of things is that coal-sales ticker over at the Web site of Peabody Energy, the world’s largest private coal company. It reels off sales at about 8 tons a second, by my estimate. As of 2 p.m. today Peabody had sold 65,246,061 tons so far this year.
Is all of this bad? If you’re one of many climate scientists foreseeing calamity, yes. If you’re a village kid in rural India looking for a light to read by, no.
Nature's Editorial (April 3, 2007)
Nature 452, 503-504 (3 April 2008) | doi:10.1038/452503b; Published online 2 April 2008
The need to transform the world's energy technology is even greater than many perceive.
How much energy, and of what sort, should we expect the world to be generating in the decades to come? This is a question of crucial importance to economics, development and the management of climate change. But as the Commentary on page 531 argues, it is not an easy question to answer (see also News on page 508).
In 2000, the Intergovernmental Panel on Climate Change introduced a range of 'emissions scenarios' that sought to estimate the amount of carbon emitted over the twenty-first century for a range of different assumptions. Climate modellers have since used a small subset of these scenarios as the basis for their analyses of possible climate change. But these scenarios are not without their controversies. One is their much-criticized approach to currency exchange rates, which some economists say overstates the impact of industrialization in developing countries. Another, it turns out, is not so much a problem with the scenarios themselves, but with the way some of them are seen as being 'business-as-usual' — in other words, what would happen if we do nothing differently.
That perception leads to an apparently straightforward measure of the climate-change problem for each scenario: take the anticipated carbon emissions and subtract an emissions profile designed to bring about a specific goal — say, a significant chance of keeping the increase in global average temperature at or below 2 °C. The result is the amount of carbon emissions that must be avoided to reach the goal. This figure, typically hundreds of billions of tonnes of carbon over the century, is then treated as the challenge that must be met by new energy technologies and efficiency drives.
But this approach brings with it a risk of double counting. The 'business-as-usual' scenarios actually assume that economies will somehow steadily increase their energy efficiency and decrease the amount of carbon they emit per unit of energy. The scenarios don't specify what technologies will be used to achieve these things, so unwary users could wrongly consider all reductions in either measure as progress over the status quo scenario. As a result, the amount of decarbonization required to achieve a stated goal is far larger than is often assumed.
The challenge is daunting enough without such misprision. An ever greater amount of world domestic product is coming from developing economies where the amount of energy used and carbon emitted per unit of economic activity is growing.
The history of the industrialized nations does suggest that there would, over time, be progress in energy technology and efficiency even without any threat of climate change. But global policy must now aim to increase this progress greatly, which means we have to accept that there are no meaningful 'business-as-usual' scenarios. The required progress requires new incentives, new research and, crucially, new costs imposed on the users of fossil fuels. It would also benefit from new economic models that, unlike the ones used with current scenarios, can show how the various policies aimed at replacing fossil fuels might work.
We also need to accept that the challenge of providing humanity with more energy in a minimally damaging way is even bigger than is usually thought. A simple calculation illustrates the point. If a growing population is to have access to the energy needed to drive development, then in 50 years the world's energy supply will need to at least double, even if energy use in tomorrow's great powers never rises to the per capita level seen in industrialized nations today, and if use in those nations is severely curtailed by efficiency improvements.
At the same time, if the world's climate is to be stabilized, carbon emissions from fossil fuels will have to be reduced dramatically in comparison with today's levels. To satisfy both those requirements, the amount of energy generated without the emission of fossil carbon needs to increase by something like a factor of ten.
That is the most daunting challenge humanity has ever sought to meet with a united front. The chances of success will be helped by models that allow different strategies to be compared. But no amount of scenario planning can replace the need for the will and leadership.