# Electric boiler



## cjsrch (May 29, 2010)

In my other topic on indoor 7.5 I mentioned electric heaters but it went in noticed any one care to comment 


This is my post from iter thread 
" 

LOL that is very true high ceilings with vent would not help since CO is heavier then air. 

However that also had me thinking about two things 
1- air powered "steamers" i saw this advertised somewhere once. instead of a boiler it is a air tank. 
2- electric heating element steamers- a 20k btu equivlent 'burner' would be apx 8 700 watt 12 volt heaters , either fire tube style or watertube could be used. 
could run each element for 1 hour on a deepcycle marine. adding 380 lbs apx tothe engine. Im crazy i know. but its not fun unless you boil water. 

Ok back to reality.  
" 

How off is my math


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## HMeinhold (Jan 2, 2008)

Do you mean something like this:


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## steamtom1 (Jan 2, 2008)

Or like this...


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## zubi (May 14, 2009)

it's been done before, just scale it up: http://www.hornby.com/livesteam/ Best, Zubi


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## cjsrch (May 29, 2010)

i think that fireless is actualy pressurized from an external source. 
im wondering if it is possiable to take a alreadymade propane or coal fired loco and fix heaters inside of the firetubes. directly transfering heat to the firetube and then to the water


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## Semper Vaporo (Jan 2, 2008)

Posted By cjsrch on 25 Feb 2011 05:50 PM 
i think that fireless is actualy pressurized from an external source. 
im wondering if it is possiable to take a alreadymade propane or coal fired loco and fix heaters inside of the firetubes. directly transfering heat to the firetube and then to the water 

"Fireless cookers" were filled with "liquid" water at a temperature way above the boiling point, but at a pressure to keep it liquid. When the throttle is opened the pressure drop allows some of the water to flash to steam and it is then fed to the cylinders just like a normal steam locomotive. They worked quite well where there was a ready supply of superheated water to replenish the tank as necessary. Some could run for hours on a full charge, but of course that depended on tonnage and distance traveled.

Putting the heaters in the flue tubes is not nearly as effecient as putting them directly in the water (fully insulated, of course!). There is no need to allow the heat to enter the smokebox and get vented up the smokestack.


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## David Leech (Dec 9, 2008)

Now, I may have some of my facts a little confused here, but!!!! 
There was an extensive use of electric steam power in Gauge O (I believe) back in the 50's by a club in the UK. 
In effect they put an electric kettle element in the boiler and ran the thing on a 'very' high voltage. 
Basically the same idea as the new Hornby OO gauge things. 
I must try an find where I read about it. 
All the best, 
David Leech, Delta, Canada


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## HMeinhold (Jan 2, 2008)

Posted By cjsrch on 25 Feb 2011 05:50 PM 
i think that fireless is actualy pressurized from an external source. 
im wondering if it is possiable to take a alreadymade propane or coal fired loco and fix heaters inside of the firetubes. directly transfering heat to the firetube and then to the water This is exactly what the Swiss did in 12" = 1' (see my first posting). The juice goes from the pantograph to a transformer and then to immersion heaters in the boiler (heaters in the fire tubes are less effective). This was done during WWII when they had ample of hydroelectric energy but no coal. One advantage of this contraption was that it could operate for a limited time on non-electrified track.
Regards


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## David Leech (Dec 9, 2008)

Okay, I just found the information that was on the G1MRA Yahoo group a long time ago. 
Here are a couple of responses about it. 
I am sure since it is all reminisces and facts that the group will not mind me quoting the information here: 
1) Yes there was such a group, but in the 1950s and late 40s It was written up in the English model railway press of the 1950s. 
The group was known as "GMT" from the initials of the principal protagonists. 
I believe that they used either stud contact or third rail for surrent pickup. 
The boilers used an electric immersion heater to boil the water, and as considerable power was needed, they used an elevated track voltage, I thought it was 90 volts AC, others have suggested 50 volts AC. 
The higher voltage reduced the current needed to heat the water. 
They superimposed a DC voltage of 12 or 24 volts onto the AC for control of the loco speed and direction, using DC motors to move the throttle and reverser controls on the loco. 

2) GMT used heaters of atleast 750 watt so current collection of around 15/20 amp was a problem. 
I also tried this method using 360watts but was not really sufficient for sustained running.At least 500/600 watts would be required!! so battery is a no no!! 

3) I recall GMT coming down to Keen House (the HQ of the Model Railway Club up passed Kings Cross going towards the Angel. 
The room was a tight squeeze for the members and their demo track and we had to be careful not to overlap the track. 
I do recall lots of sparks and arcing from the pickups but it was very impressive nevertheless. Must have been in the early 60’s. 

All the best, 
David Leech, Delta, Canada


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## cjsrch (May 29, 2010)

ok now we are getting somewhere. 

750 watts =2.5k btus/ 

i thought alot of 7.5 gauge engines used between 20k-40k bts 
20 k BTU's = 6500 watts appx = apx 550 Amp hours at 12 volts most marine batterys are rated at 60-200 amp hours granted you cant ever full drain them with out dmg


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## Pete Thornton (Jan 2, 2008)

could run each element for 1 hour on a deepcycle marine 

No you can't. While you can run a marine battery at high current for a while, the current produces so much heat in the wire and the battery that resistance rises and the current falls - if it doesn't melt first! 

My boat has a hot water heater and 3 very large marine batteries, but the heater is AC shore power (120V) only. Just running the big microwave to make coffee sucks up lots of battery power - 60 amps - from the 12V battery via the 120V AC inverter. 

I have an onboard generator that will run all the AC equipment - so you could heat the boiler from a generator - but then you are going to kill everyone in the building with CO fumes! 

Maybe you could run 120V AC from overhead wires like the Swiss? The bumper cars at the fairground also come to mind - what voltage do they use in public?


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## cjsrch (May 29, 2010)

if you double or tripple the battery numbers (run in parralell.) you are reducing the strain on the battery. i was saying that off one battery it does hold enough to do it. but you wouldent want to. also draining any battery that deep each cycle will shorten the life to almost nothing. 

also take into consideration that the heaters would not need to remain on all the time and could use PWM to change the heat and power draw. 
also you would wire it as to be 24 volts reducing the amp;s drawn and there for the gauge wire needed. 

". Just running the big microwave to make coffee sucks up lots of battery power - 60 amps - from the 12V battery via the 120V AC inverter. " so about a 700 watt microwave?


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## Pete Thornton (Jan 2, 2008)

if you double or tripple the battery numbers 
On a boat we don't have the space to consider things like that, but I guess you could use enough batteries in series to get 48V or more, which would reduce the current/heat issues. 

The marine deep cycle batteries could handle the constant draw - that's what we do every night at anchor - but they ain't cheap . .


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## HMeinhold (Jan 2, 2008)

Converting chemical energy stored in a battery into mechanical energy using steam is about the least efficient way to go. With an electric motor your conversion efficiency is about 80%, while with steam you have massive thermal losses on top of the Carnot efficiency, which limits the use of your batteries to may be 10..20%. Jensen sold an electrically heated steam engine, which delivered about 1W output using several hundred Watts of input power. Good luck! 
Regards


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## cjsrch (May 29, 2010)

hehe since when do small scale steamers pay attention to efficiency considering the smaller the boiler the greater the surface to volume ratio meaning faster cooling also smaller fire tubes would allow more heat to bypass then to transfer/ 

anyways i dont think id ever get to build this in 1/8th but in 1/32 i may try it one day. 



also are you saying for every several hundred watt input they had 1 watt of motion energy ? or 1 watt heat. 
As far as i know one watt will always be 3.41 BTU's regardless the item being a heater or a fan all will make the same heat


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## HMeinhold (Jan 2, 2008)

With a limited energy source like a battery you are definitely concerned about efficiency. Yes, the Jensen engine delivers about 1 Watt of mechanical energy. The conversion of heat into mechanical energy is governed by the Carnot cycle, which depends on the temperature differences within the system ((T2-T1)/T1). With a 1/32 engine and a power of 24V/10A, an immersion heater and good insulation you may get a loco to run. But why bother, butane is much easier... 
Regards


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## zubi (May 14, 2009)

Well, let's face it. If we are thinking about electric heaters to generate steam, there is really no need to heat water in the boiler. One could heat the water directly in the cylinders. This would make a steam 'diesel' engine, where water is injected and converted into steam in the engine. No need to insulate the boiler, and the overall efficiency would be closer to the maximum possible from the Carnot cycle. Perhaps I need to patent this!! Well, I did a quick search and it seems, Mr Crower thought of this before, or something very close http://en.wikipedia.org/wiki/Crower_six_stroke and 
http://www.autoweek.com/article/20060227/free/302270007 Best wishes from Tokyo, Zubi


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## Pete Thornton (Jan 2, 2008)

there is really no need to heat water in the boiler 
Hmmm... now I recall that the latest steam cars (including the record attempt speeder) all use "flash" boilers. Could be worth investigating - there's quite a large steam auto following on the web.


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## Charles (Jan 2, 2008)

Posted By Pete Thornton on 28 Feb 2011 09:46 AM 
there is really no need to heat water in the boiler 
Hmmm... now I recall that the latest steam cars (including the record attempt speeder) all use "flash" boilers. Could be worth investigating - there's quite a large steam auto following on the web. From the fastest ever steam power:


Steam power record 



To mass production concept:

Honda 


Not impressed try to match this by a steam powered car


http://www.newlaunches.com/archives/steam_powered_car_goes_from_0_to_343_kmh_in_25_seconds.php0 to 214 mph in 2 sec

The Bugatti Veyron which goes from 0 to 100 in around 3sec


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