As of 2007, ethanol is produced mostly from sugars or starches (zetmeel, stijfsel), obtained from fruits and grains. In contrast, cellulosic ethanol is obtained from cellulose, the main component of wood, straw and much of the plants.
The publicly traded cellulosic ethanol companies should prove to fair better. And not just production companies, but chemical companies as well.
Cellulosic ethanol could create a $3 billion to $5 billion industry in enzymes and fermentation organisms, which help break down the tough bits of the plants into fuel.
Companies in the cellulosic sector include Verenium Corporation and Bluefire Ethanol Fuels Inc. Both of those companies have received federal funding and should prove to be a good bet going forward.
It would also be wise to look at paper and pulp companies like Domtar Corp. that could start selling their byproducts as cellulosic ethanol feedstocks.
The quest for alternative sources of energy has provided many ways to produce electricity, such as wind farms, hydropower, or solar cells. However, about 40% of total energy consumption is dedicated to transportation (i.e., cars, planes, lorries/trucks, etc.) and currently requires energy-dense liquid fuels such as gasoline, diesel fuel, or kerosene.Top
Switchgrass: Yields of up to 18 tonnes dry matter/ha were found in NW Europe and up to 25 tonnes dry matter/ha were found in Southern Europe.
The cost prices for switchgrass for the different countries varied between 24 and 62 Euro per tonne.
Switch grass can net up to 400 liters of ethanol per ton, which is more efficient than corn.
This fuel is primarily being developed by Dupont and BP Biofuels, and can be fermented from biomass using a process discovered all the way back in 1916.
Butanol can be made from fossil fuels, but it can also be made from biomass. When made from biomass it is called biobutanol.
Methanol 83,000 BTUs
Ethanol 84,000 BTUs
Butanol 110,000 BTUs
Gasoline 115,000 BTUs
There are also infrastructure benefits. Unlike traditional ethanol, which cannot use the existing fuel distribution infrastructure, biobutanol can. That's because it is less corrosive and will not separate in the presence of water.Top
Ethanol, as we know it, is produced by fermenting sugars with yeast. In the production of biobutanol, fermentation still occurs, only it's done using a special bacterium instead of yeast.
The problem has been that when using this bacterium, only about 2% final fermentation product is butanol, which must then undergo an energy intensive distillation process to be purified. And there is no point in producing a fuel that takes more energy to create than it possesses. But as the process is improved, logistics are enhanced, and feedstocks are diversified, biobutanol will eventually come onto the scene in a big way.
12-4-2008
Nederland was vorig jaar de grootste buitenlandse investeerder in Brazilië. Lula (Pres. Brazilië, op bezoek in Nederland)bracht in herinnering hoe het de Nederlanders waren die in de 17de eeuw in Noordoost-Brazilië de suikerteelt opzetten en presenteerde de ethanol-samenwerking in het verlengde van deze historische banden.
Unlike petroleum, ethanol is corrosive and cannot be transported through pipelines. This leaves three options for moving it from producers in the heartland to consumers on either side of the country--trains, barges and, most likely of all, trucks. If we can find the drivers.
The WWF estimates that demand for ethanol will reach 100 billion liters by 2012, and that the United States, the biggest producer, will provide 42 percent of that. Gasoline consumption, by way of comparison, was 1.24 trillion liters in 2005.
Currently, the United States produces 28 billion liters of ethanol, followed by Brazil with 22 billion liters.Top
Hoewel suikerbieten niet te eten zijn vanwege hun hardheid, werden ze tijdens de hongerwinter in de Tweede Wereldoorlog wel gegeten, net als tulpenbollen. Men had er speciale raspen voor.
24-4-2009 Codexis --a privately held Silicon Valley enzymes company--is on firm ground, in large part because of the Shell deal. It already has revenues--$50 million in 2008--from its biocatalyst and enzyme business with pharmaceutical companies like Pfize
In 2006 and 2007, Shell invested $33.5 million for a 13% stake in Codexis; it made an additional equity investment (the amount was undisclosed) in March this year. Shell pays Codexis' biofuels research costs and will pay a royalty upon commercialization.
Codexis Redwood City, Calif., which was spun out of biotech company Mayxgen in 2002, is working with Shell to produce enzymes that will break down a variety of biomass (such as wheat grass) to turn it into fermentable sugars, which can then be made into cellulosic ethanol. A variety of companies, including Genencor (a unit of Denmark's Danisco) and Novozymes, have spent decades in the enzyme business and are working on similar projects.
But Shaw says Codexis has a unique approach in enzyme production. Instead of finding existing enzymes in places like termite bellies and improving them, Codexis scientists follow what Shaw calls an evolutionary approach. They start with DNA information of an enzyme and do sexual reproductions of millions of parents and millions of offspring, using computing power. "Each time [the enzymes] get incrementally better. This is a random but directed process," Shaw says.
Codexis is also working on improving the productivity of the fermentation process using designer microbes. Shaw says the whole process will be up and running and making money for Shell and Codexis by 2013.
Shell, meanwhile, has partnered with several companies in the biofuels sector, including Iogen in Canada, which is making cellulosic ethanol out of wheat straw. Last month, Shell announced that all its future investments in alternative energy would focus on biofuels and carbon capture and storage. Scoffone explains that "sustainably sourced biofuels could make a substantial contribution to reducing CO2 emissions. Second, they are a natural fit with our downstream capabilities in transport fuels."
De kristallen in lignocellulosevezels bijelkaar worden gehouden door meerdere netwerken van zeer sterke waterstofverbindingen. Valt een netwerk onder bepaalde omstandigheden uit elkaar, dan neemt een ander netwerk de bindende functie over.
Er zijn gelukkig een aantal zwakkere waterstofverbindingen die het molecuul potentieel blootstellen aan een aanval van cellulase entzymen. Via het manipuleren van temperatuur is het mogelijk de waterstofverbindingen te verbreken zonder dat nieuwe waterstofverbindingen een kans krijgen.
Het probleem om suikers te maken uit de zeer hechte lignocellulosemoleculen is een stukje inzichtelijker geworden.