Wouldn't a steam car have to build up a head of steam first? That would mean waiting in your car for 10 minutes or so before you can go anywhere, right? And what about leaving cars out in freezing parking lots? They would have to melt the ice in the boiler first, right?
Stanley brothers used a "flash boiler," as did a few other manufacturers.
ghlin2.greenhills.net/~apatter/whiteb.gif Kind of like the "on demand" water heaters, uses a narrow tube with water at one end, heat applied to the entire length, water boils at some point in the tube and steam comes out.
www.stanleymotorcarriage.com/GeneralTechnical/GeneralTechnical.htm"Early Stanleys were fueled with gasoline but later models incorporated a two-fuel system of gasoline for the pilot and kerosene for the main burner. Kerosene, provided not only more heat energy per unit than gasoline, it was also safer and less expensive. Both the Stanley pilot that operates continuously as well as the main burner which operates on steam demand is based on the simple principles of the Bunsen Burner. In the Stanley the heat of the fire vaporizes the liquid fuel before the fuel vapor is fed through an orifice, mixed with air, and burned below the boiler."
As for freezing, Stanleys required preheating by the user, making the morning start-up longer and inconvenient-seeming to those of us that have never had to saddle up a horse in the morning and brush it at the end of the day:
"To start a Stanley a torch is used to preheat the vaporizing tube and light the pilot making the Stanley Steamer one of the few cars difficult to steal in anything less than 20 minutes."
Compared to horse and carriage, this was pretty easy.
Stanley Steamer boilers are probably "overbuilt" - none have ever exploded. Things like that, and the preheating, are just engineering issues. Remember - Fords had to be hand-cranked to start, once upon a time, and sometimes misfires would lead to broken arms.
The answer is to lubricate the engineering department with money, coffee, and enthusiasm.
"Fuel efficiency was roughly 10-12 miles to the gallon."
The Stanley boilers were rated at 10, 20, and 30hp, depending on the model, but the "engine" part of the equation could develop 100hp for short periods. Top speeds were about 75mph, if you could find a road capable of being driven on that fast. Huge amounts of torque - you pretty much can't "stall" a steam vehicle.
The Ford Model T was rated in 1908 at 20hp and could go 45 mph, using about 25mpg.
My red minivan ,1994, gets about 14 to 20 MPG depending on the number of stopsigns in the trip. It's rated for about 160 hp, and I've driven it at a hundred miles an hour.
You have to compare the autos of 1900 to 1945 to one another and to horse-and-carriage, not to modern cars, in terms of what the consumer will find "convenient." I had a '74 VW Beetle in college, and I'd say it's every bit as inconvenient as a model T - including the lack of an electric starter, sometimes. Beetles with carb engines are about 1935 state-of-the-art in many ways. When they get old, it's like reliving 1908. Yet they sold millions.
Younger readers who've never seen under the "tupperware" of a modern engine have no idea how crude gasoline engines still are. A lot of engineering has been done in the last 20 years to make cars cleaner, more convenient to the user, and more trouble-free. But underneath the plastic tubs that cover the fuel-rail, vacuum lines, wiring harness and serpentine belts, they're still just jugs of exploding vaper. It's easy to take them for granted, because the engineers did a lot of work for us.
Electric cars are still at the point of the model T - things cludged together by a few guys in a garage are every bit as sophisticated as the product from GM featured in the Original Post video. The level of consumer-convenience will drop to bad-old-days of religiously checking the dipstick (batteries, in this case) and sometimes having to walk, before it gets to the point of convenience modern cars provide. That's what killed the electric car - the Board of Directors pulled support for a project that was going to bleed money for years, and risk the name of the company by leading the way into darkness. Sometimes pioneers get eaten by wolves blazing the trail for those who follow.
Hybrids seem to be the best of both worlds, in terms of user-simplicity, efficiency and marketability. That's gonna change what the consumer expects, leading to other market options later.
Then we need better energy storage. That's not an engineering problem - totally new science needs to be discovered.