There was some train that ran on quicklime, or something similar, I don’t remember. Basically you get heat by pouring water on it, which reacts exothermically to create heat and calcium hydroxide. The heat you then use to create steam like a normal steam locomotive. You can “charge” the train back up by turning it into quicklime again by heating it.
Theoretically you could do that with concentrated solar power. Aside from the steam turbine, it’s pretty low tech.
This is really cool and lines up neatly with some discussions RoboGroMo and I have been having around solar furnaces, do you remember anything else about it - like was this historical or a research project/prototype? I’m having trouble finding it.
I’ve been looking many times, asking ChatGPT, I think I’ve seen it on the YT channel Train of Tought, but I can’t find it. Feels like Mandela Effect lol. I fear I made it up. So, source: it came to me in a dream.
I wanna say it was a small Swiss system and some time around the World Wars. I think because there was a fuel shortage or something? Like I said it might have been something other than lime.
But it didn’t use solar, just some regular fuel like wood.
But you can achieve high enough temperatures with less than a 1m² fresnel lens to melt rock into obsidian, so you can dry slaked lime too. That’s why I suggested it.
But you can do the math, how much quick lime you would need (one litre of water combines with approximately 3.1 kilograms of quicklime to give calcium hydroxide plus 3.54 MJ of energy) to generate enough heat to drive a train (various size trains use like 100-1000kW) a useful distance and how much volume that is. Then you just need to calculate how much energy you need to dry that amount, then you can calculate how much solar power you need (you know like if you need 10kW, you need at least 10m² worth of solar at 1000W/m² solar irradiance).
I think you would need around 10t (I trippled the weight because most steam engines are only around 30% efficient) of quicklime to power a 1000kW train for 1 hour. Union Pacific big boy weighs 544t and has a power of 5200kW, so a 1000kW should have around 100t of weight. Also you need to store 1kg of watee for every 3.1kg of quicklime. If you try to keep within those limits a quicklime train only has enough fuel for a few hours maybe.
But I guess you could make it heavier if you aren’t transporting that much cargo or change locomotives or quicklime tenders every few hours.
So you would need like 1000m² of solar power (e.g. from concentrator mirrors) to power a train like that continuously. Including efficiency losses, lack of sunlight etc, you can probably 10x that number or more to keep the train running 24/7.
I guess you could also skip the quicklime and just power trains with solar directly by attaching a 1000m²+ solar concentrator blimp to it. After all, steam locomotives really run on heat, not coal. I guess the Hindenburg had 10 000m² of surface area, so just make it transparent and able to focus the sun on a precise spot on the ground and you can run your 1000kW solar powered steam train. lol
Kinda like that, but zeppelin sized attached to your train:
I guess you could do that with cargo ships too.
As long as the drag if that zeppelin doesn’t eat up all the power lol.
Also you don’t need to check my math, I guarantee you it’s off by orders of magnitude.
There was some train that ran on quicklime, or something similar, I don’t remember. Basically you get heat by pouring water on it, which reacts exothermically to create heat and calcium hydroxide. The heat you then use to create steam like a normal steam locomotive. You can “charge” the train back up by turning it into quicklime again by heating it. Theoretically you could do that with concentrated solar power. Aside from the steam turbine, it’s pretty low tech.
This is really cool and lines up neatly with some discussions RoboGroMo and I have been having around solar furnaces, do you remember anything else about it - like was this historical or a research project/prototype? I’m having trouble finding it.
I did stumble onto this, which could perhaps work with fixed site solar concentrators to recharge the superheated water resivoires https://en.m.wikipedia.org/wiki/Fireless_locomotive
I’ve been looking many times, asking ChatGPT, I think I’ve seen it on the YT channel Train of Tought, but I can’t find it. Feels like Mandela Effect lol. I fear I made it up. So, source: it came to me in a dream.
I wanna say it was a small Swiss system and some time around the World Wars. I think because there was a fuel shortage or something? Like I said it might have been something other than lime.
But it didn’t use solar, just some regular fuel like wood.
But you can achieve high enough temperatures with less than a 1m² fresnel lens to melt rock into obsidian, so you can dry slaked lime too. That’s why I suggested it.
But you can do the math, how much quick lime you would need (one litre of water combines with approximately 3.1 kilograms of quicklime to give calcium hydroxide plus 3.54 MJ of energy) to generate enough heat to drive a train (various size trains use like 100-1000kW) a useful distance and how much volume that is. Then you just need to calculate how much energy you need to dry that amount, then you can calculate how much solar power you need (you know like if you need 10kW, you need at least 10m² worth of solar at 1000W/m² solar irradiance).
I think you would need around 10t (I trippled the weight because most steam engines are only around 30% efficient) of quicklime to power a 1000kW train for 1 hour. Union Pacific big boy weighs 544t and has a power of 5200kW, so a 1000kW should have around 100t of weight. Also you need to store 1kg of watee for every 3.1kg of quicklime. If you try to keep within those limits a quicklime train only has enough fuel for a few hours maybe.
But I guess you could make it heavier if you aren’t transporting that much cargo or change locomotives or quicklime tenders every few hours.
So you would need like 1000m² of solar power (e.g. from concentrator mirrors) to power a train like that continuously. Including efficiency losses, lack of sunlight etc, you can probably 10x that number or more to keep the train running 24/7.
I guess you could also skip the quicklime and just power trains with solar directly by attaching a 1000m²+ solar concentrator blimp to it. After all, steam locomotives really run on heat, not coal. I guess the Hindenburg had 10 000m² of surface area, so just make it transparent and able to focus the sun on a precise spot on the ground and you can run your 1000kW solar powered steam train. lol
Kinda like that, but zeppelin sized attached to your train:
I guess you could do that with cargo ships too.
As long as the drag if that zeppelin doesn’t eat up all the power lol.
Also you don’t need to check my math, I guarantee you it’s off by orders of magnitude.
Thanks for doing the math on this!
Is this what you were thinking of? http://www.douglas-self.com/MUSEUM/LOCOLOCO/soda/soda.htm
yeah I think that’s it