Walther engine: an interesting fuel experiment.

Injecting water and sulfur acid or hydrogen peroxide into diesel engine cylinders makes a new type of steam engine. And that is an interesting attempt to replace petroleum from cars. 

In the 1910's before service stations, some cars used steam engines. The steam engine cars were popular until the gas station network was comprehensive enough. Those petroleum stations left steam engine cars into history. But it's possible that if the engineers had put their time into "precisely operating steam engines" those steam cars would not be put into history. The precisely operating engine means that the system injects water and sulfur acid or hydrogen peroxide into the combustion cylinders. When hydrogen peroxide or sulfur acid is injected into those chambers it creates heat and steam.  

Sometimes, researchers introduced that the diesel engine could be turned into a steam engine. They could operate without fossil fuels by using peroxide or sulfur acid-water mixture as the tool that replaced the combustion. In that system, another line transports water into the cylinder. Then the fuel injector injects sulfur acid or hydrogen peroxide into the cylinder. That kind of system can make it possible to create a new type of steam engine that should not create pollution. The problem is that the sulfur acid itself is a very corrosive thing. But it's possible that if that kind of system were created in the 1910's those steam engine cars still exist. 

The Walther turbine is used in torpedoes. The system works with hydrogen peroxide that reacts with water. The 90+% hydrogen peroxide will conduct to the turbine along with water. The chemical reaction creates heat and water vapor. And then that pressurized steam rotates turbines. In some other versions, the system uses sulfur acid that reacts with water and creates heat and vapor as hydrogen peroxide. In those systems, the attempt to replace fossil fuel was because the fuel must be stored in torpedoes. In the 1940's during WWII. German researchers developed submarines that used hydrogen peroxide and water as tools that created the steam for turbines that the submarine could use in underwater drive. 

Those systems gave test submarines an impressive underwater speed of 20-29 knots, which was much more than the normal diesel-electric propulsion. During WWII Germans built 31 (12A and 19B models) XVII-type submarines. But after WWII the interest in that system ended. And the reason was that. The hydrogen peroxide was expensive. The system could use sulfur acid for the same purpose, but for some reason, those systems didn't too flame. 

https://en.wikipedia.org/wiki/Type_XVII_submarine