Function

The German forest alone grows by around 3 m³ every second. One third could be used for the production of fuels. Already after the Second World War there were vehicles with 'wooden carburetors' (see pictures 2 and 3). These were monsters which did not only take possession of the whole boot, but often even jutted out of it, because they were larger than the boot space. In spite of operating them at the limit, the effect was only moderate, and it produced a lot of dense smoke and even more cleaning work afterwards. There you can see that the technology has made considerable progress.

The leap to renewable raw materials has to be made in the not too far future, especially in the light of further rising oil prices, the knowledge that the oil sources are finite, and the approaching CO2 disaster.Besides the production of bio-diesel there are at least two processes for the petrol engines with which the fuel is produced industrially. They use biomass, consisting of almost everything that grows on fields, including timber.

How it works

Ethanol (alcohol) is used as fuel for the automobile already as long as the internal combustion engine exists. Already the first prototypes were operated with it. Early racing cars achieved impressive results with special mixtures however made up of fossil fuel. This indicates an advantage of Ethanol; it has a considerably higher octane rating and would, presumed the engine would be adapted in terms of compression and the characteristic engine maps would be altered, manage a clearly higher performance. Indeed, the engine would use, nevertheless, 20 - 30% more fuel because Ethanol contains one third less energy. Though, this is valid only for monovalent systems. Being able to operate the engine also with petrol, the conversion is clearly more difficult. There are systems in the pipeline, e.g., the variable compression with which the switch from petrol to ethanol and vice versa would be possible without performance losses or a higher fuel consumption due to the switching. The supercharging has progressed already much further. Controlling the boost pressure electronically up to 20% increased performance can be achieved currently (2006). Looking at the technology present right now you may hope for 15 to 20 percent of fuel savings in Germany.

Bio ethanol consists of 85% Ethanol and 15% petrol. For operating the engine, materials must be implemented or exchanged that are less prone to chemical decomposition e.g. the piston surface and the fuel pipes.

Vehicles for Ethanol operation are offered lately also by manufacturers directly from the factory. We may hope that a European-wide filling station network develops for Ethanol what would allow a monovalent operation. Maybe subsequently the surcharge for these vehicles can be lowered and the range of action with one filling. State subsidies would become obsolete. Particularly Sweden is ahead currently (2006). The country has reduced its dependency from crude oil to one fourth. Brazil already earlier switched to this form of energy. 7 out of 10 cars are operated with Ethanol in Brazil. However, such an extreme switch supports the one-sided, not unproblematic cultivation of sugarcane. Moreover, the sugarcane edges out the rain forest.

Another approach is based on the already available natural gas network and some filling stations connected to it already. It is anyways a pity to burn this valuable raw material. It also has a higher octane rating and it has almost the same specific features in terms of the insertion in the petrol engine car like with Ethanol. Except maybe that the tank must be a little more voluminous and more pressure resistant. But a filling station network is already in progress in Central Europe. But, what is the relation between natural gas and biomass? The production of biomass should occur decentralised. Best of all in the midst of many fields because the transportation to the processing facilities is one of the few negative points in the production process. Almost all remaining energy can be gained from the process itself.

Solving the transportation problem is possible with the help of the natural gas network. There are (2007) first projects in Germany with which after the standards of a certain network natural gas is produced out of biomass and feed into the existing natural gas network. Thus agricultural products can obtain a considerable utility value, instead of being stored running into a lot of money. You have to say goodbye to the idea that food is just intended for eating, and should not be misused as fuel.

On top in the picture a model of the low temperature carburetor is visible. Below the bio coke appears and on top the low temperature carbonisation gas comes out. The latter still contains tar which is removed in the carbon V carburetor. This forms the heart of the system after which it is also named. The heat exchanger heats the gas and gets out the steam. Once dedusted and washed the combustible gas emerges.