Better Cars

A better first step would be to increase the gas mileage of cars. The WWII Jeep, the first Volkswagen Beetle, and the diesel version of the Volkswagen Rabbit all ran with only 25 HP. The most popular version of the Beetle which was in production for a decade had a 1.3 Liter engine which produced only 36 HP. Even if we include the modern demand for air conditioning this would only round it up to 40 HP. Yet, today, there is not a single compact car manufactured or sold in the US that has less than 100 HP. This seems very strange. Further, by using composite materials which did not exist when the Beetle was designed in 1940's, we could easily reduce the vehicle weight from the original 1,900 lbs. A 50% reduction in structural weight is possible but a 1/3^rd reduction is quite easy and could be done in the near future. The original engine also weighed a hefty 200 lbs. A modern engine of this same HP would only weigh 80 lbs. This would allow an immediate reduction in weight to just 1,200 lbs with an equivalent savings in fuel in city driving. Highway mileage would also be increased both by weight reduction and better streamlining of the body. With reduced weight, a 40 HP Beetle would perform better with four people on board than the original did with just one.

The main reason that these cars are not being pursued by manufacturers is economics. It costs almost as much to make a compact car as a mid sized car even though the mid sized car sells for much more. It would take a novel approach to production and pricing to make compacts profitable again. However, it would be in the strategic interest of the US to do so, and therefore certainly the duty of the US government to encourage and foster, since for each 12% improvement in fuel economy the demand for oil Worldwide would be reduced by 1%. Since the same weight reduction techniques can be applied to mid sized and larger cars a 12% or greater reduction in fuel consumption is quite easy to do. Assuming we could change the economics of compact cars this would be the best path for reducing oil consumption in the US. Perhaps the government should sponsor novel design contests or even give grants to start production of good designs. Although, it is also likely that the traditional auto industry would invest in production on their own if the designs could be produced and a ready market demonstrated. This almost certainly needs some investment by the federal government however as in the current economic climate for automobiles in the US it is not likely that Ford, Chrysler, and GM will stray too far from established paths.

With a lighter body it is even possible that less than 40 HP would be needed. Another really good approach is to use a hybrid design. This works even better if less horsepower is needed. The generator can charge the battery in the most optimal manner rather than having to change rpm as the vehicle accelerates. However, a hybrid design would also open the door for the use of the Stirling engine. This engine was tested by GM in the 1970's. It's biggest problem was that it took about a minute to warm up enough to start. And, most consumers are not that patient. However, a hybrid design would have no such problem since it would simply move under battery power while the engine warmed up. A Stirling would have many advantages over internal combustion engines. Since there is no need to burn the fuel in a fraction of a second there is almost no pollution produced. This would avoid almost all of the modern emissions controls on cars as well as most of the complex ignition and fuel injection systems. The engine would be very simple and therefore cheaper and more reliable. This too would be a big boost to economics of compact cars. We could avoid the current problem of engine compartments which are too tight to work in and engines so complex that they require engine analyzers to diagnose problems. The burner for a Stirling would be very simple and only need a simple ignition source to light. Since combustion products would not mix with the oil, the oil would not need to be changed as often and the engine would wear less. The engine needs no muffler and no catalytic converter which reduces weight and volume. These would all be advantages for a Stirling hybrid.

However, there is another big advantage of an external combustion engine. Not only would it be possible to charge the batteries from other sources but the engine itself would be capable of using many different types of fuels. Such an engine could burn gasoline, fuel oil, diesel fuel, kerosene, cooking oil, lamp oil, or alcohol. It could also be fitted to burn gases like propane, methane, or hydrogen. This would give maximum flexibility in choosing the most economical fuel. Overhauling the current hybrid to reduce weight and replacing the current gasoline or diesel generator with a Stirling would be the best route to maintain the flexibility of the automobile if oil prices and availability become a factor in the future. Likewise this would give us maximum flexibility in meeting conditions for reducing greenhouse gases if such a treaty becomes law. This appears to be more and more of a likelihood. Therefore, sponsoring research into weight reduction and hybrid Stirling designs should be a matter of national interest.