SUMMARY PRODUCER gas plants have been made in portable sizes for lorries, tractors, small stationary sets, motor boats, etc., for some years, and remarkable economy in the cost of fuel can be obtained by using producer gas plants and charcoal or low-temperature coke as fuel instead of petrol.
The plant consists of a gas generator fitted with a hopper on the top to contain charcoal or coke. The gas is generated by the induction through the gas generator which is connected to the induction pipe on the engine. The cleanser or filter box is placed on the gas pipe between the generator and the engine to take out any dust or foreign matter which may be in the gas.
There are no working parts with modern English portable producer gas plants and there is therefore nothing to wear out or replace, except perhaps the fire-brick lining in the body of the gas generator. Increased cylinder radio is advisable in order to get maximum power out of the gas, and this is nearly always supplied by the first-class makers of portable producer gas plants. Plants will then work satisfactorily with any " petrol " type of engine using either petrol or kerosine. In continental practice wood is frequently used and converted into charcoal in the generator, but in best English products the recommendation is to make the charcoal separately.
Amongst the advantages of producer gas plant in comparison with petrol fuel and the carburettor is the clean gas which is obtained. This is free from carbonising effect in the cylinders and has no such detrimental effect to the lubricating oil in the crank-case as petrol may have in engines with slack-fitting pistons and leaking piston rings. Another advantage in tropical climates is the fact that a good deal of pilferage takes place with highgrade spirit as well as leakage and evaporation.
The criticisms mostly made against portable producer gas plants are the time taken to start up in the morning, which is anything from 8–12 minutes with the modern English producer gas plant and the extra weight of 2j cwts. Also possibly the unsightly appearance and the time taken to clean the ash out of the gas generator and dust out of the cleaner box. This does not take long with the modern plant, not more than a few hours per week.
A recent test of 100 miles with a 30-cwt. Ford truck under average working conditions using low-temperature coke, size I" X I", shows a.cost of 2s. 3d. for the run as compared with the cost for the same journey on petrol of 9s. lld., thus showing a saving of 77J% in the cost of fuel. In tropical countries where charcoal is cheap and easily obtainable and petrol is expensive and difficult to obtain, the difference may be greater. A report on a set working under ordinary conditions in S. India shows that the cost of fuel for the last six months works out at Id. per mile. The plant working is under adverse conditions as the lorry runs up to elevations o