Wood gasification, cogeneration and green electricity
published: 17/07/07, 10:27
As the subject intrigued quite a few people, here is a very concrete example of a wood gas cogenerator.
Found on: http://www.econologique.info/index.php/ ... issinfoorg
While renewable energy was struggling, the threat of oil shortage and climate change gave them a boost. But pioneers have been at work for a long time ...
The Bosshard family, for example, with Woodpower AG near Wila in the canton of Zurich, produces CO2-neutral current and heat by gasifying wood.
The idea was born three years ago: father and son Bosshard, owners of a wood construction company in Wila, wanted to secure their future by seeking new perspectives.
“Woodpower was born out of necessity, but not only. There was also an interest in new technologies, because we are a family of DIY enthusiasts, and then we wanted to do something for the environment, ”explains Oliver Bosshard with pride.
By chance, they came across a small wood gasification plant and started to think about the possibility of commercial exploitation. They researched the Internet, searched for contacts and investors around the world.
During the change of supply network, the Zurich electricity company EKZ became aware of the existence of this company like no other and was interested in it. Today, EKZ owns 49% of the capital of Woodpower.
Indian technology
Wood carburetors were already used at the time of the 2nd World War, in particular to replace gasoline. They were fed with beech wood and installed on trucks. Then this technology fell into oblivion.
Besides, the Bosshards have found no model of commercial exploitation in Europe. But, finally, in India, where there were forty years of experience. "It is rather curious to seek out know-how in a country which, if not, imports everything from Western countries," observes Oliver Bosshard.
To generate electricity, the company uses unused wood waste collected from the surrounding area. “There is enough wood here. If it had to be transported over long distances, the benefit for the environment and the company would be reduced. ”
The old wood is first burned, and produces wood gas, composed of carbon monoxide, dihydrogen and methane. Before introducing the gas into the current generator, it must be cleaned of all tar, which is evacuated with special waste.
Burning wood is part of the natural carbon cycle: it does not release more CO2 than the tree needed for its growth, which means that the electricity thus produced is neutral compared to with greenhouse gases.
Heat and current
But electricity only constitutes a third of production. The main thing is the heat. A small part is used for drying the wood used for power generation. And most of it to make wood chips. The drier they are, the better the combustion.
Oliver Bosshard adds that, since the installation was commissioned at the start of the year, they have been overwhelmed with demands. He does not know if his adventure will be successful in Europe. But the 'childhood illnesses' are now over, there are only a few adjustments left. According to his most conservative estimates, his business will be profitable in two years.
The energy of the future
For EKZ and the Bosshards, this innovative and unique installation plays a pilot role, a demonstration role too: there are visitors every day. Banks and electricity groups invest in renewable energy, in short, the green current is very trendy.
The Confederation also wants to encourage this sector. This is explained by Michael Kaufmann, vice-director of the SFOE: “Projects like Wila's have a future. Switzerland has great potential in terms of biomass, wood, organic waste, and it is a question of exploiting it. Energy is outside our door. ”
Michael Kaufmann is delighted to see this kind of project emerge. But this type of installation must have a certain size, not too large either, so as not to harm the environment, for example with transport that is too long.
Advance cautiously
Recently, the UN warned of the negative effects of bioenergy, but its benefits should not be overlooked either. "I would like to remind you that fossil fuels have far more serious effects on the environment and society," says Michael Kaufmann.
“As this is only the beginning of renewable energies, we have the opportunity to learn the necessary lessons from it.” And, therefore, avoid negative developments. "The use of biomass must not harm the population, agricultural production or the ecosystem."
swissinfo, Gaby Ochsenbein
(Translation and adaptation from German: Isabelle Eichenberger)
Found on: http://www.econologique.info/index.php/ ... issinfoorg