My grandfather was a farm equipment dealer in Saskatchewan when my dad was a boy, and my dad would sometimes hang around the dealership office. There would often be farmers there, also hanging around, or huddling around the wood-burning stove, talking and arguing, and one main argument was the old question of gas tractors versus steam tractors. Actually by then gas had won, and it was more of a lament by the steam guys. Now you might say that was a no-brainer, a modern diesel a quarter the size does as much work as those old smoke-belching, water-using, occasionally exploding steam monsters, but then, you haven’t heard the argument.
Actually, the argument was about engines burning the fuel inside the power-producing cylinder in a sort of controlled explosion, so they need very special, manufactured fuel, and the products of combustion get into the engine working parts so it won’t last very long, and come out as a stinky exhaust. As against burning the fuel in a furnace, and taking the heat to an engine which would turn it into mechanical power, so that the fuel could be anything that will burn, and the fine working parts of the engine are kept clean and will last much longer. There is no explosion, so there is no noise, and the exhaust is clean. The farmer stays independent of industry – they don’t have an engine busy self-destructing on its fuel byproducts, needing expensive parts, and they don’t have to buy fuel from a factory, so easy and convenient for the government to tax. Steam tractor equals free and independent; gas or diesel tractor equals government and industry taking your money to the city.
And stop thinking about those monsters you see trundling around at the Austin fair – that is nineteenth century technology – they hadn’t even invented radio yet, much less computers. Think instead about Mr. Lear – not King Lear, but Lear the inventor/ entrepreneur/ self-made millionaire who invented mobile radios, and later built the Lear jet. His next project was the Lear car, and it would be external combustion – able to burn any fuel. He had prototypes built, and was getting close to the market when he met an untimely death – you conspiracy theory believers can speculate that maybe the government or auto industry or both had him done in, to keep this great advance off the road.
The old steamers had a big boiler full of water, and a fire had to burn long enough to heat all those tons of steel and water up to boiling point – hours – before you could even move it, not very practical for a car although we have all heard of the Stanley Steamer. The steam was then drawn off to the engine, and after it did its work it was exhausted, so the tractor needed lots of water, and its downfall was the rust and scale that all that water left in the boiler. Lear was experimenting with fluids something like Freon, working in a closed cycle in the same way it does in your refrigerator. It would use a flash boiler, in which the flame heats up a small chamber, so warmup time is very short. An electric pump would inject liquid Freon into the hot chamber, where it would instantly evaporate (flash) to vapour, under pressure. The vapour would be run through a tiny little turbine, spinning about a zillion revs and running a generator. Electric motors in the wheels would make the car go. The exhaust from the turbine would be Freon gas under low pressure; this would be condensed to liquid again by cooling it in a radiator, and pumped back up to the flash chamber by the electric pump. No steam escapes, and no big vessel full of boiling water to explode in spectacular fashion if something goes wrong, which was the real bugaboo of the old steamers. The only exhaust is that from the burner, and you know how clean that can be – the exhaust from your modern furnace comes out that little plastic pipe at the side of your house, and has no smell, well ok, maybe a slight odour of roses. Best of all, you can burn almost anything, canola oil, homebrew, pellets made from straw or sawdust or even garbage – no fuel bill!
External combustion is long past its time, but of course it can’t happen. How would they tax you if your car could run on wood or corn or pellets or your morning newspaper? How would they sell new cars and endless service and parts keeping those internal combustion engines going if cars would last forever?