Even if they could only be used on certain routes set in specific time periods I suggest the implementaion of fireless locomotives specifically of the steam type. Used as shunting locomotives in industrial areas they became especially popular in Germany in the 20th century and some countries like the GDR ordered them as late as the 1980s. Some are still in use with an example being at a coal power plant at Mannheim. How they work: Being similar to a conventional steam locomotive, but instead of a boiler there´s a reservoir. This reservoir is charged with superheated waer under pressure from a stationary boiler. The engine works like a conventional steam engine using the high pressure steam above the water in the accumulator. As the steam is used and pressure drops, the superheated water boils, replacing the used steam. The locomotive can work like this until the pressure has dropped to a minimum useful level or the water runs out, after which it must be recharged. Where they could be used: Usable on Routes set in the last century mainly at coal power plants, chemical, paper or ammunition production or in mining. They were used mainly in locations where no open fire is allowed due to the risk of an explosion or widespread fire and the availability of steam is already on location. Disadvantages are a limited range of operation and the dependence on an external boiler. Meanwhile low maintenance requirements and costs and no environmental pollution are there advantages. Sources: wikipedia (german page: https://de.wikipedia.org/wiki/Dampfspeicherlokomotive ) (english page: https://en.wikipedia.org/wiki/Fireless_locomotive )
I love this idea. It is essentially a stem engine and should be an easy build. In addition they look about the same in each country.
There are a couple of small fireless loco's in preservation near me- one is on display at Locomotion in Shildon. Note that they have the cylinders at the cab end to keep the steam pipes as short as possible. The examples I've seen have bells instead of whistles, again to conserve steam, and one has a cosmetic funnel because it just didn't look right without one.
