Monthly Archives: January 2013

Crooked Willows Make Better Fuel

An experiment, which findings have  appeared in the Biofuels journal,  has encovered that willow trees grown at an angle produce five times more biofuel than willows grown diagonally. According to the research, done by the Imperial College London, crooked willows produce a special kind of wood that results in higher sugar content.

willow

Willows are traditionally grown for wicker furniture and baskets, but the leaves and bark of the willow tree also have been used a precursor of asprin.  At the moment,  the short rotation coppice crop is mainly grown as a resource for the biofuel and biomass industry. Willow appears to produce the highest yield of biomass compared to other woody biomass crops, making it a good source for renewable bio-fuel.

Scientists were previously unable to explain why some willows produced more biofuel than others.  The British scientists now found  that when trees are blown sideways some trees have a genetic make up which allows them to produce strengthening sugars which try and make the tree grow straight again. These sugars boost  the amount of biofuel that can be released from the tree. Michael Ray, a researcher at Imperial College London, explained to the BBC; “The phenomenon we are investigating is a natural phenomenon that is observed in most trees. You get a special type of wood (known as reaction wood) laid down in response to environmental stimuli, such as tipping or wind, which induces these special woods to be formed.”

The researchers preditct that in the future all willow crops could be bred for this genetic trait, making them a more productive and greener energy source. The biofuel willow crops could be grown in climatically challenging conditions where the options for growing food crops are limited.

See this video for more informationon this subject

Via: BBC News and RDmag.com

The Global Soya Bean Problem According to Lester Brown

The global demand for soya beans has increased 16-fold in the past few  decades. The largest demand originates from China, which predominantly uses soya to feed pigs, poultry and farmed fish. This may well cause problems according to environmentalist Lester Brown

Lester Brown, who has being named  as “one of the world’s most influential thinkers” by the Washington Post,  started his career as a farmer growing tomatoes in New Jersey.  He joined  the U.S. Department of Agriculture’s Foreign Service as an international analyst in 1959, before graduating in Agricultural Economics.  In 2001 he founded  the Earth Policy Institute , an organisation that aims for an environmentally sustainable economy. Brown has been monitoring the effects of unsustainable development and forecasting their possible consequences. He is now, and has been,  warning the world about China’s (soya) consumption, believing that it’s rising demand will bring about consequences that will be felt all over the world.

So why doesn’t China produce more soya itself? The answer lies in 1995, when the Chinese government decided, with the Great Chinese Famine of 1959 in the back of their heads, to focus on being self-sufficient in producing grain.  They dreaded having to be dependent on the rest of the world for their grain supplies once more.  As a result, grain production in China became heavily subsidised, which was detrimental to the country’s soya production. In order to meet demand, China is now forced to import large quantities of the bean. The effects are beginning to make themselves felt on western agricultural soils.

Momentarily the U.S. has more land where soya beans are being grown, than grain. In Brazil, the land in soya beans exceeds that of all grains combined. Argentina’s soya bean area is now close to double that of all grains combined, putting the country dangerously close to becoming a soybean monoculture.  Nearly 60% of all soya beans entering the international market today go to China, making the country the world’s largest importer of soya beans by far. China’s soya demand has risen greatly in the past decades.

It wasn’t until the 1950s that the soya bean, domesticated in China some 3,000 years ago, joined wheat, rice, and corn as one of the world’s four leading crops.  Animal nutritionists had discovered that combining one part soya bean meal with four parts grain would sharply boost the efficiency with which livestock and poultry converted grain into animal protein. Seeing that half of the worlds’ pig population can be found in China and together with the countries fast-growing poultry industry and large quantities of farmed fish in the country demand for the bean went up. To illustrate; in 1995, China was producing 14 million tons of soya beans and  consuming 14 million tons. In 2011, it was still producing 14 million tons of soya beans but now consuming 70 million tons, meaning that 56 million tons had to be imported.

Since the mid-20th century the yield of grain production has risen in ratio to land use, whereas soya beans still require vast amounts of land.  Grain yield has tripled per acre, the 16-fold increase in the global soybean harvest has come largely from expanding the amount of crop lands. While these area have been expanded nearly sevenfold, the yield has scarcely doubled. This is where the problem lies.

Soya bean

Do we have any land left to plant the soya beans which are so in demand? There is no available cropland left in the United States. Making room for soya beans can only been done by shifting land from other crops, such as corn or wheat. In other countries, like Brazil, the result has been that the Amazon Basin and the cerrado (a vast tropical savannah) are being traded in for soya bean cropland. 

To save the Amazon rainforest, which destruction will cause even more environmental problems down the line, we have to find a way to reduce the demand for soya beans. One way to do it, according to Brown, would be to stabilize the world population, another would be for us all to eat less meat (and not use soya as a substitute, of course). Americans still eat more meat than anyone else in the world, but consumption is, luckily, declining now according to recent publications.

Via: www.earth-policy.org/data_highlights/2013/highlights34

 

First Hybrid Train Takes Passengers through Germany

The first hybrid train with a new regenerative braking system is being trialled in Germany. The train will be taking passengers on a 37 km (22 miles) route between Aschaffenburg and Miltenberg.

Railroad track in SwitzerlandMost trains can work on both diesel and electric motors, depending on the track, and half of Europe’s train-tracks are electrified, so why haven’t we seen hybrid trains before?  This is due to high capital investments, the extreme conditions faced by trains on a daily basis and reliability. All these factors ensure that the development of hybrid trains has been limited mostly to shunting locomotives (called switching engine or switcher in the US),  which have particularly high energy losses.

The German train, a Siemens Desiro Classic VT 642 locomotive, which is now the first hybrid in the world taking passengers, was originally diesel powered and equipped with two 275 kilowatt engines. The train has been supplied with regenerative braking capacity and two 315 kilowatt-rated hybrid power packs.

MTU, the subsidary of Tognum, a manufacturer of large diesel engines, has developed the braking system that uses a generator to convert the kinetic energy generated during braking into electrical energy. This electrical energy is temporarily stored in lithium-ion batteries before being used again for starting, accelerating or for supplying electrical loads on the train. The battery packs are placed on the roof, where they are cooled by the air streaming across the top of the train whilst it’s in motion.

The new system is intended to reduce fuel consumption and greenhouse gas emissions by 25%.  As the trail-route has 14 stops, the train will have plenty of opportunity to use the braking system and to recharge the train’s batteries.

If the system proves to be a success, the authorities hope that all the existing trains can be converted to hybrids in future.

You can see an animation video of how the train works here

Via: Treehugger

Scientists Find Way to Boil Water Using Sunlight

Scientists from the Rice University in Houston, Texas, have developed a new technology that uses nanoparticles to convert solar energy directly into steam with an overall energy efficiency of 24 percent. The research was published in ACS Nano.

The team from Rice’s Laboratory for Nanophotonics (LANP) used light-capturing nanoparticles to convert sunlight into heat. By submerging  the light-capturing nanoparticles  in water and exposing them to sunlight, the particles heat up so quickly they instantly vaporize water and create steam. So it doesn’t require boiling water. The  method, the scientists refer to as “solar-steam””, works in a different way than conventional solar thermal panels, that can only heat up water slowly.

The solar steams’ overall efficiency of the 24 percent is quite high compared to the efficiency of photovoltaic solar panels, which have an overall energy efficiency of around 15 percent. The LANP – team says the overall energy efficiency can probably be increased as the technology is refined.

On Rice University’s website LANP Director Naomi Halas, the lead scientist on the project, explains why they managed to achieve such high efficiency: “We’re going from heating water on the macro scale to heating it at the nano-scale ” Halas said. “Our particles are very small — even smaller than a wavelength of light — which means they have an extremely small surface area to dissipate heat. This intense heating allows us to generate steam locally, right at the surface of the particle, and the idea of generating steam locally is really counter-intuitive.”

The solar steam method is apparently so effective,  it can even produce steam from icy cold water. This video shows how the LANP-team creates  steam from almost frozen water.  Water with added nanoparticles sits in an ice bag, a lens is used to concentrate sunlight onto the near-freezing mixture in the tube. The nanoparticles heat up and produce steam. The technology converts about 80 to 90 percent of the energy coming from the sun into steam.

Stoom- NZ

According to the researchers, the technology can play an important part  in low-cost sanitation, water purification and human waste treatment for the developing world. Although its not the initial intended use , it could be very interesting exploring this technique for the generation of electricity by using steam. Perhaps with a steam turbine as a converter?

 

Via:  news.rice.edu/2012/11/19/rice-unveils-super-efficient-solar-energy-technology-2/