The Model T as the Killer App of Cars

E-mail was the killer app (application) that made Internet access "must have" for modern man and the Model T was the killer app that made the automobile a "must have" in its day. Neither technology was a new invention, both had existed in various forms for at least a decade before their broad public introduction. The thing that made them killer apps is that they had arrived at the evolutionary stage where they were seen as practical and cost effective. E-mail got there with the 14.4 Kb/s dial-up modem, remember those? I’ve had a decade long career as an Internet publisher, and I’ve been on dial-up for all but eight months of that period. The Model T became the killer app of the automotive world with 20 horsepower engine and a 1200 pound curb weight, and it likewise showed it’s worth for over a decade.

The world may have changed quite a bit between now and then, but I have to believe if people could buy street legal Model T’s to tool around the country for $850 (their introductory price), there would still be a market. What that tells me about automotive technology as a starting point is that you can get by with 20 hp. I’ll get into what a horsepower actually is in the next post, but for the time being, lets look at some comparisons. I’ve seen SUV’s advertised on TV with 300 horsepower engines, talk about a waste of resources. On the other hand, a 125cc Honda dirt bike with a total weight of 180 pounds could also boast 20 horsepower a couple decades ago. I rode a 100cc Honda for a few summers, it had plenty of power to go wherever you wanted, though it got blown around a bit by passing trucks.

The relationship between horsepower generated by a motor and speed achieved by a vehicle depends on several factors, the gearing in the drive train, the friction losses in the drive train, the aerodynamic losses to wind, even the rolling friction of bearings and soft tires. Well, that’s not exactly right either, since a small horsepower engine can move a car along just as fast as a large horsepower engine, particularly if the car isn’t very heavy and you don’t exceed the speed limit by an excessive amount. The main difference horsepower makes in this case is how quick you can get up to that speed. If you drive like an idiot and never learned how to merge, horsepower can be very useful, but in most cases, it’s just not necessary.

So, our adoption of the Model T as the killer app of cars means if we build a 1200 pound electric car and put 20 horsepower of motors into it, we should have the start of a useful car. Whether or not it will have a useful range with the number of batteries we can afford to carry to keep the weight down will be another question for another day, but it’s a start. For what it’s worth, I expect we’ll be able to get more useful work (speed and acceleration) out of our 20 horsepower than the Model T did with its two speed transmission.