Experiences gained from conversion and operation of modern vehicles
.2.1 The need for continued practical tests
Producer gas was used as a substitute fuel for almost all the vehicles operated in Sweden during the Second World War. Some improvements of the gasifier and the gas cleaning technology have been made since then. This does not necessarily mean that producer gas is still a realistic option for substitution of petroleum fuels in case of a supply crisis. The current engines are different from those used in the forties and so are the vehicles. For an assessment of the present possibilities of producer gas, it is therefore important to collect and evaluate experiences from operation of modern vehicles with this fuel. Tables 3.10 and 3.11 list tractors and trucks converted to producer gas in Sweden after the Second World War. The majority have been converted and tested by the National Swedish Testing Institute for Agricultural Machinery, and have been used for practical operation for several years, monitored by the Institute. These tests have been concentrated on dual fuelling of compression-ignition engines. The operating experience now covers more than 65000 km for trucks and 15000 hours for tractors.
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Table 3.9 Results of scoping tests with various biomass fuels in the standard gasifier for wood chips
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cut |
Gasitier F3u0 |
Some slagging. Power output І97% of that for wood chips. |
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jCoconut shell crushed I |
‘Tractor: Bolinder — iMunktell BM650 iGasifier F300 |
17 h of operation. Excellent performance. Power output 103% of that for wood chips. |
Good fuel for the present gasifier. I |
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.COoOi lUt .husk, cut |
Tractor: Bolinder- Munktell BM650 Gasifier F300 (wood block configuration). ____________________________________________ |
2.5 h of opeiatioii. No bridging, but some slagging observed. ’Power output 102% of that for wood chips. _ |
Test too short for conclusion. Absence of bridging is promising. Slagging indications shows that more frequent cleaning of gasifier may required. |
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Table 3.10 Tractors converted to producer gas operation in Sweden after the Second World War |
In addition, the Institute has converted and operated one passenger car, an Opel Rekord 1700, which has been driven for more than 47000 km with a wood chip gasifier. The Swedish car manufacturer Volvo has converted and operated three passenger cars, one Volvo 142 and two Volvo 144, with engine types B20.
Recent conversions of trucks have been made by the Beijer Institute for field tests in developing countries and by a private company.
The most comprehensive operating record for modern tractors and trucks has been collected within the programme conducted by the National Swedish Testing Institute for Agricultural Machinery. It’s experiences with two of these vehicles, a truck and a farm tractor are presented below.
Field tests with each particular vehicle model and for all operating conditions are obviously necessary for a complete assessment of producer gas as a vehicle fuel. The experiences described can serve only to provide some guidance as far as the technical performance, service and maintenance requirements and equipment lifetime are concerned.
The experiences are not related to the most recent models of vehicles and are not necessarily transferable to the operating conditions of other countries. The field tests in developing countries planned by the Swedish International Development Authority and other international development assistance organizations will provide valuable complementary information.