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Author Topic: Fuel Cell vs ICE  (Read 2801 times)

KaiserDunk

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Fuel Cell vs ICE
« on: 09 January 2019, 13:41:29 »
Very simple question since I have not yet been able to get my hands on TacOps; for the purposes of writing fluff for a combat vehicle, how does the operation of a fuel cell powerplant differ from that of a combat vehicle ICE powerplant?

TigerShark

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Re: Fuel Cell vs ICE
« Reply #1 on: 09 January 2019, 13:58:37 »
Fuel cells use a different fuel type. They explode on a critical hit (when mounted in 'Mechs), same as ICE engines. Their weight is much lower and they supply a single heat sink when installed.
These engine types are not widely used due to fuel availability and cost, since fossil fuels are more abundant. They are most commonly found in IndustrialMechs and civilian vehicles. TacOps notes that they can be used on military vehicles "on request," but are not typically offered up-front in a new design.
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AdmiralObvious

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Re: Fuel Cell vs ICE
« Reply #2 on: 09 January 2019, 14:26:54 »
Fuel cells can be used underwater and in space. The common ICE can't, so that's one other difference between the two. The fuel cells usually come with their own oxidizer, usually hydrogen and oxygen, and it basically works like a contained rocket engine, and it spits out water when done.

The ICE uses fuel, of course, and fuel doesn't burn without said oxidizer.

Either way, both will explode when shot at too much.

Sartris

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Re: Fuel Cell vs ICE
« Reply #3 on: 09 January 2019, 14:28:11 »
Range is another one. An ICE engine has fuel for 600km (20,000 hexes at cruising speed). A fuel cell has a lesser range of 450km (15,000 hexes) (TechManual pg. 68)

KaiserDunk

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Re: Fuel Cell vs ICE
« Reply #4 on: 09 January 2019, 14:56:42 »
Thank you.   It sounds like the fuel cells are like what are commonly used on current space craft.   That definitely helps.

Atarlost

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Re: Fuel Cell vs ICE
« Reply #5 on: 09 January 2019, 16:46:53 »
Realistically, ICE should only exist on civilian vehicles on pre-fusion worlds that happen to have oil.  Fuel Cells run on Hydrogen just like fusion reactors and just like fusion reactors if you have a fusion reactor in your force you can make it from water.  ICE runs on liquid hydrocarbons and these are only available on worlds that have had mass extinctions that produced oil beds and that have developed infrastructure to extract and process them, or that have lots of biomass and have developed infrastructure to process that into hydrocarbons, but this is higher tech infrastructure as it requires a power source.  Any world that retains fusion (doesn't have to be mobile) will find it easier to use fuel cells even if it also has accessible oil.  The oil can be used for plastics and a chemical industry for export to those poor benighted worlds that don't have oil.  A world that has never had an extensive biosphere (eg. Trell I) will have no local hydrocarbon source, but any world fit for human habitation has to have water and thus hydrogen and any attacking force has to have a dropship and thus a fusion power plant to crack that water for hydrogen. 

Sabelkatten

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Re: Fuel Cell vs ICE
« Reply #6 on: 09 January 2019, 18:06:27 »
IIRC fuel cells were originally included in "ICEs", just like gas turbines, batteries and advanced steam engines or similar. Btw piston engines, gas turbines and steam engines run fine on Hydrogen (piston engines might require quite a bit of adjusting).

Personally I ignore the name and just call FCEs advanced ICEs!

Daryk

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Re: Fuel Cell vs ICE
« Reply #7 on: 09 January 2019, 19:40:14 »
Just to be clear, Fuel Cells are NOTHING like rocket engines.  They are used on real world spacecraft, but that's about the only commonality I can think of.  [/physics major]

AdmiralObvious

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Re: Fuel Cell vs ICE
« Reply #8 on: 09 January 2019, 21:59:43 »
Just to be clear, Fuel Cells are NOTHING like rocket engines.  They are used on real world spacecraft, but that's about the only commonality I can think of.  [/physics major]
Yeah, I should've made that clear. It works with the same principle... but not at all...

Daryk

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Re: Fuel Cell vs ICE
« Reply #9 on: 09 January 2019, 22:04:33 »
I'm really not sure what principle you're referring to... Fuel Cells chemically convert fuel into electricity while rocket engines generally turn fuel into thrust physically (an argument can be made regarding ion engines, but they convert electricity into thrust)…

boilerman

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Re: Fuel Cell vs ICE
« Reply #10 on: 09 January 2019, 22:32:35 »
And they are not heat engines so their upper limit of efficiency is not limited by Carnot's Law.   :)
The main reason I prefer them in BT over ICE engines; though this has no effect in BT rules.

A little add on for BT fuel cells is you get a 1 free heatsink. I find it annoying you still have to use power amplifiers are for energy weapons with a fuel cell, which generate electricity directly. But I just chalk that up to all the capacitors you need to store enough energy to power a BT energy weapon.
« Last Edit: 09 January 2019, 22:50:19 by boilerman »
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Kovax

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Re: Fuel Cell vs ICE
« Reply #11 on: 10 January 2019, 11:47:15 »
Note that an ICE can be built (or possibly reconfigured) to run on alcohol, oil, hydrogen gas, or almost any other flammable liquid or gas.  They're not limited to worlds with petrochemical deposits or imported gasoline.  Virtually any planet with a breathable atmosphere and able to support even limited agriculture will be able to produce fuel for ICE engines, and many without such amenities will still be able to manufacture it by utilizing local chemical deposits to produce flammable liquids.

My assumption is that many vehicles will have a drivetrain mechanically coupled to the engine (as per the modern day "car"), while others will have an engine which drives a generator, and run off stored electrical power using electric motors (gas-electric hybrids).  The former will be simpler and cheaper to build, but have more restrictions as to fuel type, while the second could have different engines (reciprocating piston, gas turbine, fuel cell, or small fusion reactor) dropped in easily during final assembly, depending on what types of fuels are available at the location where it will be used.  Even if the engine itself is fusion in that individual vehicle, the overall vehicle design and level of performance would still be considered "ICE".

As shown by Tesla, the latter type, with electric motors, can out-perform a mechanically coupled internal combustion engine for brief periods, limited primarily by battery storage capacity.  Having a small or modest-sized "engine" to recharge the batteries would allow far greater duration in the field than a purely battery-powered design which would need frequent breaks for recharging.

Jellico

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Re: Fuel Cell vs ICE
« Reply #12 on: 15 January 2019, 21:20:01 »
Note that an ICE can be built (or possibly reconfigured) to run on alcohol, oil, hydrogen gas, or almost any other flammable liquid or gas.  They're not limited to worlds with petrochemical deposits or imported gasoline.  Virtually any planet with a breathable atmosphere and able to support even limited agriculture will be able to produce fuel for ICE engines, and many without such amenities will still be able to manufacture it by utilizing local chemical deposits to produce flammable liquids.


Fuel Cells run on hydrogen. Literally the most common element in the universe. If you have water (I assume your crew is drinking something) you have hydrogen. The limited factor is conversion which requires large amounts of electricity. If it is an industrial society you have that electricity. Heck. If you flew in by DropShip you have a fusion reactor. If you are Invading a world FC is better than ICE because you don't need to transport fuel.

Really the limiting factor with FC is the tech to build the engine.

More importantly why is any society more advanced than our own using ICEs over FCs?

Atarlost

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Re: Fuel Cell vs ICE
« Reply #13 on: 15 January 2019, 21:28:20 »
Fuel Cells run on hydrogen. Literally the most common element in the universe. If you have water (I assume your crew is drinking something) you have hydrogen. The limited factor is conversion which requires large amounts of electricity. If it is an industrial society you have that electricity. Heck. If you flew in by DropShip you have a fusion reactor. If you are Invading a world FC is better than ICE because you don't need to transport fuel.

Really the limiting factor with FC is the tech to build the engine.

More importantly why is any society more advanced than our own using ICEs over FCs?

If it weren't for the issue with fuel cell engines on supersonic conventional fighters not making sense I'd suggest swapping the fluff, weight, cost, and introduction dates wholesale so that FCEs were the ones everybody used by default and ICE was what you used to squeeze a few extra tons at the expense of needing to worry about special fuel. 

AdmiralObvious

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Re: Fuel Cell vs ICE
« Reply #14 on: 15 January 2019, 21:29:15 »
Fuel Cells run on hydrogen. Literally the most common element in the universe. If you have water (I assume your crew is drinking something) you have hydrogen. The limited factor is conversion which requires large amounts of electricity. If it is an industrial society you have that electricity. Heck. If you flew in by DropShip you have a fusion reactor. If you are Invading a world FC is better than ICE because you don't need to transport fuel.

Really the limiting factor with FC is the tech to build the engine.

More importantly why is any society more advanced than our own using ICEs over FCs?
Because it's relatively cheap to manufacture compared to a FC? Sure, the fuel itself is easy to find and produce. Making something to contain the reaction, or even start it, especially in the outer sphere/pererphiery is pretty hard to do, where in rare cases, you're still using coal fired steam engines to get around.

Terrace

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Re: Fuel Cell vs ICE
« Reply #15 on: 16 January 2019, 00:59:41 »
I was messing around in MegaMekLab and took advantage of Fuel Cell's big advantage over ICE to upgun a Vedette to sport an AC/10 and extra armor.

Because that's the most noticeable advantage of the FC in a one-shot tabletop game: drastically reduced weight means you can stuff bigger/more guns onto the same chassis. Is the fuel restrictions important in a campaign? Sure. But as has been said, if you've got a Fusion Engine hanging around nearby, making more hydrogen mitigates that disadvantage neatly.

Edit: I just realized that the example I gave was basically a Po that shrank in the wash and picked up some extra speed in the process.
« Last Edit: 17 January 2019, 10:00:05 by Terrace »

Col Toda

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Re: Fuel Cell vs ICE
« Reply #16 on: 16 January 2019, 06:49:56 »
Fuel Cell engine have approximately the same motor power on a combat vehicle as a light Fusion engine plus shielding . I have done upgrades to most canon ICE vehicles to Fuel Cell and upgraded the Patton and Romel Fusion tanks because it has only a small laser and the one heat sink handles that .

Jellico

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Re: Fuel Cell vs ICE
« Reply #17 on: 16 January 2019, 07:27:27 »
RS3060 Update was possibly the first major project where this was noticed by the designers after FCs were introduced. You could hear the squeals of glee across the internet.

Elmoth

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Re: Fuel Cell vs ICE
« Reply #18 on: 16 January 2019, 08:28:38 »
I would assume that a fuel cell would NOT be great for vehicles with energy weapons since they would deplete it fast (no idea on rules, just gut feeling), but othewise running on an alkaline tank in the future makes sense, specially if you expect to control the time of the engagement. Refuelling can me complicated otherwise.

The_Caveman

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Re: Fuel Cell vs ICE
« Reply #19 on: 16 January 2019, 09:31:12 »
If a fuel cell breaks down, you basically have to replace the whole thing because it runs off a specially-manufactured chemical catalyst and there is no real way to fix that in the field.

If an ICE breaks down, any shadetree mechanic in the Inner Sphere can fix it with common shop tools.

Maintenance rules don't reflect this, so to get around that I would say fuel cells are built as progressively-larger stacks of universal modules. Plug-and-play. But you still gotta have the modules on hand to do repairs, whereas an ICE just requires having access to a machine shop and steel billets.
Half the fun of BattleTech is the mental gymnastics required to scientifically rationalize design choices made decades ago entirely based on the Rule of Cool.

The other half is a first-turn AC/2 shot TAC to your gyro that causes your Atlas to fall and smash its own cockpit... wait, I said fun didn't I?

Sartris

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Re: Fuel Cell vs ICE
« Reply #20 on: 16 January 2019, 12:39:41 »
RS3060 Update was possibly the first major project where this was noticed by the designers after FCs were introduced. You could hear the squeals of glee across the internet.

that was mostly me

I would assume that a fuel cell would NOT be great for vehicles with energy weapons since they would deplete it fast (no idea on rules, just gut feeling), but othewise running on an alkaline tank in the future makes sense, specially if you expect to control the time of the engagement. Refuelling can me complicated otherwise.

they require power amplifiers like ICE vees with energy weapons but there are no special rules that affect fuel consumption


since most of this science is mercifully left out of the rules, the only thing that really matters is that cell engines are super light.

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Re: Fuel Cell vs ICE
« Reply #21 on: 16 January 2019, 17:36:46 »
More importantly why is any society more advanced than our own using ICEs over FCs?

ICE covers things like coal, wood, biodiesel still, aye? Engines that any half-awake tech can figure out and can be rigged to run on whatever's both local and suitably flammable presents a fantastic choice for logistics. The important people have the technology, but let the indigs get by with chichken farm and their fuel-chugging old pickup and you won't have to waste good resources keeping them running. ol' cletus can just fix everything hisself and think he's important for that...
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MoneyLovinOgre4Hire

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Re: Fuel Cell vs ICE
« Reply #22 on: 16 January 2019, 20:21:28 »
If a fuel cell breaks down, you basically have to replace the whole thing because it runs off a specially-manufactured chemical catalyst and there is no real way to fix that in the field.

If an ICE breaks down, any shadetree mechanic in the Inner Sphere can fix it with common shop tools.

Maintenance rules don't reflect this, so to get around that I would say fuel cells are built as progressively-larger stacks of universal modules. Plug-and-play. But you still gotta have the modules on hand to do repairs, whereas an ICE just requires having access to a machine shop and steel billets.

How does repairing a fuel cell compare to repairing a damaged nuclear fusion reactor?

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Kovax

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Re: Fuel Cell vs ICE
« Reply #23 on: 17 January 2019, 11:25:45 »
How does repairing a fuel cell compare to repairing a damaged nuclear fusion reactor?
You don't glow afterwards.

The_Caveman

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Re: Fuel Cell vs ICE
« Reply #24 on: 17 January 2019, 13:02:06 »
Fuel cells are solid-state devices by their very nature. It's a sandwich of metals and polymers. There's nothing really to repair if it gets broken, aside from the fuel lines and electrical cables that connect it to the chassis.

AFAIK fusion engines have always been described as having moving or at least removable parts of some manner (though the writers are understandably cagey about getting too detailed). In high-tech eras, those probably could be fixed at least at depot-level. Deep in the LosTech era, you'd probably have to just yank any mysterious magic components that got damaged and replace them with spares (probably sourced from a different design, while praying to Blake that the whole thing doesn't explode when you turn it on), so not much different from a FC.

In 3025 a fuel cell gives you all the headaches of a fusion engine with none of the "pew pew lazors" goodness that makes fusion engines attractive to begin with. It does let you build a tank that can operate in vacuum, though.
Half the fun of BattleTech is the mental gymnastics required to scientifically rationalize design choices made decades ago entirely based on the Rule of Cool.

The other half is a first-turn AC/2 shot TAC to your gyro that causes your Atlas to fall and smash its own cockpit... wait, I said fun didn't I?

Colt Ward

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Re: Fuel Cell vs ICE
« Reply #25 on: 17 January 2019, 14:42:18 »
To me FCEs were a boon for the 'cheap' ICE/AC line tanks . . . what you can do with a Vedette, Po and Zhukov with a FCE and 3050 weapons gets kind of crazy.  Vedette gets options to make it a real cavalry mech for post 3050- bigger gun, more armor, faster- maybe a supercharger!  Sure it costs more now than the bog standard Vedette but your combat capability goes up more dramatically IMO- and your logistics gets simpler for offensive forces.  Give the Po a Gauss Rifle and X-SPL instead of MG for Anti-Inf, more armor and survivability- AMS, maybe ECM, maybe A-pods.  The Zhukov gets better guns (GR, LBX & large MML rack) with more ammo and more armor- maybe bumped to 4/6.

From a logistics standpoint, ICE vehicles always struck me as placed more in defensive formations.  Offensive formations should have fusion engine vehicles so you do not have to worry about capturing fuel (easier to destroy defender stockpiles than capture) and their range in support of mechs is not limited by fueling needs.  You will also not need to transport the initial fuel requirements of the armor forces though support (ammo trucks, ambulances, mobile kitchens, repair trucks) will still have those needs.
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Maingunnery

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Re: Fuel Cell vs ICE
« Reply #26 on: 17 January 2019, 16:25:50 »

I usually use Fuel Cells when designing environmentally sealed vehicles, these compensate each other quite well.
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Jellico

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Re: Fuel Cell vs ICE
« Reply #27 on: 17 January 2019, 16:55:46 »
Personally when I first started designing with FCs they struck me as Clantech ICEs.

More advanced tech. Lighter. Less range.

Of course they haven't been used that way but I feel that you can make an argument that FCs should replace most of the ICEs in Clan service right down to the very low civilian end. You could say the same for the Star League given what they have been fluffed to have been running in civilian vehicles.

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Re: Fuel Cell vs ICE
« Reply #28 on: 17 January 2019, 18:54:58 »
Colt, at the low tonnage end, even support forces are ultimately cheaper with fusion engines.  The 25 rated engine is extremely useful, and not that expensive.

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Re: Fuel Cell vs ICE
« Reply #29 on: 18 January 2019, 02:14:52 »
After I saw this I tried to build a flying Hetzer (with a MRM 40 as the cheep-o big boomstick) in MegaMek Lab with a fuel cell. 
It turns out that conventional aircraft in Lab at least can't be given a fuel cell engine. 

I was wondering if this was in the rules anywhere or just an issue in Lab? 
Is it the range restriction on fuel cells that prevents you from powering a plane with them, even if you allocate extra tonnage for fuel?  Or is there some other catgirl killing reason that a fuel cell wouldn't work.

The_Caveman

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Re: Fuel Cell vs ICE
« Reply #30 on: 18 January 2019, 09:34:56 »
After I saw this I tried to build a flying Hetzer (with a MRM 40 as the cheep-o big boomstick) in MegaMek Lab with a fuel cell. 
It turns out that conventional aircraft in Lab at least can't be given a fuel cell engine. 

I was wondering if this was in the rules anywhere or just an issue in Lab? 
Is it the range restriction on fuel cells that prevents you from powering a plane with them, even if you allocate extra tonnage for fuel?  Or is there some other catgirl killing reason that a fuel cell wouldn't work.

Fuel cells can only power prop-driven aircraft. They don't produce thrust directly like turbines and aero-fusion engines. You can't build a conventional fighter with props, but you can do it as a fixed-wing support vehicle.
Half the fun of BattleTech is the mental gymnastics required to scientifically rationalize design choices made decades ago entirely based on the Rule of Cool.

The other half is a first-turn AC/2 shot TAC to your gyro that causes your Atlas to fall and smash its own cockpit... wait, I said fun didn't I?

Colt Ward

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Re: Fuel Cell vs ICE
« Reply #31 on: 18 January 2019, 11:56:50 »
Colt, at the low tonnage end, even support forces are ultimately cheaper with fusion engines.  The 25 rated engine is extremely useful, and not that expensive.

Sure, but typically you are grabbing whatever trucks you can since they never get the production priority of actual combat machines.  Now something like the Davion Brigade of Guards, 1st FS Armored Cav, Lyran Royals, Sword of Light, and other elite commands may get all their vehicles to match up.  But the Ghost & Legion of Vega regiments?  They are likely seizing the trucks they need from militia units on planet or even businesses to meet their TO&E needs before boosting for a invasion- and taking more when they land to use.
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Atarlost

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Re: Fuel Cell vs ICE
« Reply #32 on: 18 January 2019, 13:15:14 »
After I saw this I tried to build a flying Hetzer (with a MRM 40 as the cheep-o big boomstick) in MegaMek Lab with a fuel cell. 
It turns out that conventional aircraft in Lab at least can't be given a fuel cell engine. 

I was wondering if this was in the rules anywhere or just an issue in Lab? 
Is it the range restriction on fuel cells that prevents you from powering a plane with them, even if you allocate extra tonnage for fuel?  Or is there some other catgirl killing reason that a fuel cell wouldn't work.

Fuel cells create electricity.  You can't power a jet engine with electricity.  Propellers or rotors can be powered by electricity but cannot reach the speeds of even conventional fighters.  You can't break the speed of sound with a propeller except possibly in a dive where it's gravity doing the work.  No catgirls, just actual physics and aerodynamics.  Thus, VTOLs can use fuel cells but conventional fighters cannot. 

The_Caveman

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Re: Fuel Cell vs ICE
« Reply #33 on: 18 January 2019, 14:03:42 »
You can't power a jet engine with electricity.

Not strictly true, as an electrically-driven compressor tied to an expanding nozzle is still a jet engine. But compared to a conventional gas turbine it would be heavy and inefficient. Or a gas turbine where the combustor was replaced with an electric heating element--but again, this would add dead weight and suck up lots of power for no real benefit.

It only makes sense with nuclear power, where there is abundant electrical power and lots of free waste heat to dump into the working fluid, and no significant fuel mass to worry about.

There's no technical reason you couldn't make a fuel cell-powered jet, you just wouldn't want to. It'd be the worst of both worlds.
Half the fun of BattleTech is the mental gymnastics required to scientifically rationalize design choices made decades ago entirely based on the Rule of Cool.

The other half is a first-turn AC/2 shot TAC to your gyro that causes your Atlas to fall and smash its own cockpit... wait, I said fun didn't I?

AdmiralObvious

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Re: Fuel Cell vs ICE
« Reply #34 on: 18 January 2019, 16:07:07 »
Not strictly true, as an electrically-driven compressor tied to an expanding nozzle is still a jet engine. But compared to a conventional gas turbine it would be heavy and inefficient. Or a gas turbine where the combustor was replaced with an electric heating element--but again, this would add dead weight and suck up lots of power for no real benefit.

It only makes sense with nuclear power, where there is abundant electrical power and lots of free waste heat to dump into the working fluid, and no significant fuel mass to worry about.

There's no technical reason you couldn't make a fuel cell-powered jet, you just wouldn't want to. It'd be the worst of both worlds.
I mean, if you have enough power, you can make a resistojet out of it. Its grossly inefficient, as you're basically burning a lightbulb to ignite (more) fuel, but even then you're better off just using your typical combustion reaction.
« Last Edit: 18 January 2019, 16:21:48 by AdmiralObvious »

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Re: Fuel Cell vs ICE
« Reply #35 on: 23 January 2019, 10:38:00 »
I was messing around in MegaMekLab and took advantage of Fuel Cell's big advantage over ICE to upgun a Vedette to sport an AC/10 and extra armor.

You can install a Gauss Rifle keeping the 5/8 movement and add some more armor in a Vedette with FCE. Scary.
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Colt Ward

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Re: Fuel Cell vs ICE
« Reply #36 on: 23 January 2019, 11:13:43 »
UAC/10, more & HFF, and put a SC . . . now THAT is a cav tank!
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Nebfer

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Re: Fuel Cell vs ICE
« Reply #37 on: 29 January 2019, 16:47:15 »
Range is another one. An ICE engine has fuel for 600km (20,000 hexes at cruising speed). A fuel cell has a lesser range of 450km (15,000 hexes) (TechManual pg. 68)
Thats for Battlemechs (well Industrialmechs)
IIRC the Errata for vehicle range states that the fuel tank is 10% of the engines mass, and follows support vehicle rules so 100km for an ICE is 1% of the engines mass, Fuel cell is 1.5%

So a ICE equipped tank has a range of 1,000km and Fuel cell 667km.
Though Industrial mechs it's as you state, 600km for ICE and 450km for fuel cell, an extra fuel tank is 10% of the engine and doubles the range (I.e. it adds an extra 600 or 450km of range).


As for the Topic at hand
IIRC Fuel cells are more expensive than ICE but are cheaper than Fusion, they also weigh less than fusion engine vehicles (which are also lighter than ICE), as such unless you want to use a lot of energy weapons or are worried about refueling, then Fuel cells are better then ICE or fusion engines. On the other hand the Light and XL Fusion engines are lighter than Fuel cells.

In short
ICE: Still good for extremely dirt cheap units, but pore on anything else
Fusion: Good for unlimited range or energy weapons, other wise inferior payload to Fuel cells
Light & XL Fusions: Have better payload than Fuel cells as well as being better for energy boats

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Re: Fuel Cell vs ICE
« Reply #38 on: 29 January 2019, 23:05:49 »
More importantly why is any society more advanced than our own using ICEs over FCs?


Because by 3025 many worlds were less advanced than our own, not being able to manufacture anything above 80s level technology.
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MoneyLovinOgre4Hire

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Re: Fuel Cell vs ICE
« Reply #39 on: 29 January 2019, 23:14:08 »
Some worlds, especially in the Davion Outback and the Periphery, can't even properly be said to be industrialized.

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Re: Fuel Cell vs ICE
« Reply #40 on: 30 January 2019, 00:59:52 »
In which case they import.

Mobile phones are ubiquitous in Africa but they certainly don't make them there. Mr Scott was Scottish because Scottish steam engines were exported to every Victorian hell hole in the world in the 1800s.

I get that industrial levels may be low but in this case that is mostly about maintenance. These guys maintain nukes with gaffer tape and chewing gum. But the barrier to build any sort of engine is high and I am not sure that most will bother.

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Re: Fuel Cell vs ICE
« Reply #41 on: 30 January 2019, 03:19:27 »
Those places probably aren't going to have a lot of combat units beyond infantry in the first place.  It's not like there's much that's actually worth fighting over on any of them.

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Re: Fuel Cell vs ICE
« Reply #42 on: 30 January 2019, 04:47:07 »
There is always something that might interest a raider. Not all fights are against invaders after all, but most are against raiders. There are raids for water in official sources after all. Beats me how that is relevant considering the tinny cargo capacity of dropships, and the fact that the raiders could simply *buy* a hundred thousand tons of water for a fraction of the cost of a single point of mech armor but hey. Water raids are there none the less and outback countries will have those for sure and other resources.

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Re: Fuel Cell vs ICE
« Reply #43 on: 30 January 2019, 09:14:32 »
Those places probably aren't going to have a lot of combat units beyond infantry in the first place.  It's not like there's much that's actually worth fighting over on any of them.

There’s probably always a demand for water purifying equipment and the like with pirates

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Re: Fuel Cell vs ICE
« Reply #44 on: 30 January 2019, 22:03:36 »
I wish there were a long-lived radioisotope of oxygen. It would make the difficulty of water purification in BT so much more believable.

Much of the easily-available water could be heavily tritiated. Although with a half-life of just 12 years tritium is a short-term contaminant. There would need to be a radioactivity source constantly replenishing the tritium in order to make the water dangerous over long periods.

So that requires either cosmic rays or contamination by certain types of nuclear fallout.

The latter explanation strongly favors the "nuke everything anywhere near anything" view of the 1st and 2nd Succession Wars that the writers have recently shyed away from. Without heavy NBC contamination it's a lot harder to justify those water raids. Since a planet bathed in cosmic rays would be uninhabitable anyway.
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Re: Fuel Cell vs ICE
« Reply #45 on: 31 January 2019, 00:47:38 »
ICE is supposed to be a far more developed technology than Fuel Cells for military purposes. Military ICE is supposed to be able to run effectively on a variety of fuels, and be easily maintained in the field. Fuel Cells existed in the civilian market, but could never compete with Fusion for efficiency in military deployment. Much like Tripod mechs and superheavies, Fuel Cells are a technology that piddle around in the background for centuries because it never hit the critical mass of R&D to find its niche until after the disruptions of the Jihad made people re-evaluate the assumptions made during the Star League.
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Re: Fuel Cell vs ICE
« Reply #46 on: 31 January 2019, 11:46:30 »
I wish there were a long-lived radioisotope of oxygen. It would make the difficulty of water purification in BT so much more believable.

Much of the easily-available water could be heavily tritiated. Although with a half-life of just 12 years tritium is a short-term contaminant. There would need to be a radioactivity source constantly replenishing the tritium in order to make the water dangerous over long periods.

So that requires either cosmic rays or contamination by certain types of nuclear fallout.

The latter explanation strongly favors the "nuke everything anywhere near anything" view of the 1st and 2nd Succession Wars that the writers have recently shyed away from. Without heavy NBC contamination it's a lot harder to justify those water raids. Since a planet bathed in cosmic rays would be uninhabitable anyway.

Biological contamination that is part of the world's native biosphere but is persistent.  AFAIK only a few places in the world produce the fine filters for the best RO processes, most 'water purification' stuff just gets out the large contaminates, removes smells and relies on all the chlorine (or derivatives) that bleaches everything in the water to make it 'clean.'  In addition you have the degree of difference between industrial sized applications and personal applications for the RO.

Desal?  Huge plants and IMO would really should be used since the tech is simpler . . . but it will wear out as well.
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Kovax

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Re: Fuel Cell vs ICE
« Reply #47 on: 31 January 2019, 12:49:26 »
There’s probably always a demand for water purifying equipment and the like with pirates

Either that, or they know that a lot of planets will pay good money for such equipment, regardless of its source.

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Re: Fuel Cell vs ICE
« Reply #48 on: 31 January 2019, 13:13:21 »
Either that, or they know that a lot of planets will pay good money for such equipment, regardless of its source.

Triple expansion Steam Evaporation will usually get biologicals out, and it's low tech....just energy intensive.
Saying that because the equipment isn't up-to-the-minute, bleeding-edge tech therefore not a threat is like saying an M2 Browning isn't dangerous to modern infantry because it is 100 years old.

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Re: Fuel Cell vs ICE
« Reply #49 on: 31 January 2019, 13:19:25 »
What about going the other way.

Instead of having the water purifying equipment deal with pollution, imagine them making water of extreme high quality, with just the right mixture of compounds/trace elements to enable extreme longevity. There will be plenty of demand for that.
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Re: Fuel Cell vs ICE
« Reply #50 on: 31 January 2019, 15:11:02 »
Fuel cell engines would, ironically, make great ad-hoc water generation systems.

Hydrogen and oxygen go in, electricity and pure water come out.

Ultimately the problem with purification being difficult is that if you have abundant electrical power you can just heat water to temperatures where the molecules dissociate, which will kill anything. The constituent gases are easy to separate from any chemical contaminants at that point. Some light centrifuging and a controlled combustion reaction later, and you have potable water. Fission, nevermind fusion, makes this trivial to do.
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The other half is a first-turn AC/2 shot TAC to your gyro that causes your Atlas to fall and smash its own cockpit... wait, I said fun didn't I?

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Re: Fuel Cell vs ICE
« Reply #51 on: 31 January 2019, 15:18:37 »
Yeah, but then that also would suppose 3SW most planets were using coal or gas fired plants.

Additionally, if you were the House Lord would you want some underling messing around with nuclear power on their planet . . . where they might be able to sneak through either dirty bombs or even a full fledged weapons program?  What took geniuses at the beginning now takes well trained technicians as long as they have the tools- why give some future rebel such tools?
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MoneyLovinOgre4Hire

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Re: Fuel Cell vs ICE
« Reply #52 on: 31 January 2019, 15:36:45 »
I'm pretty sure that the nuclear genie is sufficiently out of the bottle by the time of the Star League's formation that it's really not possible to prevent a determined group from building their own low-yield nuke if they wanted to.

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Re: Fuel Cell vs ICE
« Reply #53 on: 31 January 2019, 15:51:13 »
I'm pretty sure that the nuclear genie is sufficiently out of the bottle by the time of the Star League's formation that it's really not possible to prevent a determined group from building their own low-yield nuke if they wanted to.

Right. Not to mention fission plants are looked down on as downright primitive technology even in the LosTech era.

WMDs aren't used for cultural reasons, not technological ones. Anyone with a flyable DropShip technically has their hands on a WMD comparable to a dinosaur-killer asteroid.
Half the fun of BattleTech is the mental gymnastics required to scientifically rationalize design choices made decades ago entirely based on the Rule of Cool.

The other half is a first-turn AC/2 shot TAC to your gyro that causes your Atlas to fall and smash its own cockpit... wait, I said fun didn't I?

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Re: Fuel Cell vs ICE
« Reply #54 on: 31 January 2019, 16:20:30 »
I'm pretty sure that the nuclear genie is sufficiently out of the bottle by the time of the Star League's formation that it's really not possible to prevent a determined group from building their own low-yield nuke if they wanted to.

Which is why I said it takes a good technician with the tools.  The tools are going to be the limiting factor and depending on what type of bomb is being built will make determine if/type of reactor is needed.


Right. Not to mention fission plants are looked down on as downright primitive technology even in the LosTech era.

WMDs aren't used for cultural reasons, not technological ones. Anyone with a flyable DropShip technically has their hands on a WMD comparable to a dinosaur-killer asteroid.

Fission is looked down on?  Sure from the golden Star League age where every SL city was powered by some giant fusion plant.  But those fusion plants started falling apart and the ability to maintain them became limited- so which planet is likely to get fusion spares, New Avalon or Outback Central?  And since the SL era fusion plant no longer works and is stripped for parts to maintain fusion plants on more important worlds.  So what does that planet replace their non-functioning fusion plant with during or towards the end of the 2SW?  Fission?  Why would a House Lord allow it to be built or make the parts even available since tech & shipping is at a premium?  A planet is more likely able to make a coal, oil or gas fired power plant out of their own sources which leaves a advanced factory trying to keep up with the demand for fusion plant spares as more of the advanced factories get nuked.  Each world would also have to build the industries that would lead to a nuclear reactor; the threshold for hydro or c/o/g plants is a lot lower.

While the IS population might be scarred by the NBC exchanges of the 1SW & 2SW the House leaders are still going to take steps to keep that sort of resource out of other people's hands.
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The_Caveman

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Re: Fuel Cell vs ICE
« Reply #55 on: 31 January 2019, 23:55:07 »
Why would a House Lord allow it to be built or make the parts even available since tech & shipping is at a premium?

Who says a House Lord has that kind of authority? They're not interstellar dictators. If a duke or earl wants a nuclear program in his own sub-realm, that's his business under the feudal code. The House Lord isn't likely to start a civil war over it since there are bigger fish to fry. And if anyone is that afraid of nuclear weapons, thorium breeder reactors are a safer, difficult-to-weaponize option.

But again, nobody freaks out over random civilians having their own DropShips because using them as relativistic weapons is just not the done thing, despite a Union that has expended all its fuel burning at a planet being deadlier than Earth's entire present-day nuclear arsenal combined. The trouble and expense of a secret nuclear weapons program just isn't worth it even for terrorists. Even a K-1 DropShuttle has the potential to be a multi-gigaton impactor.

Quote
A planet is more likely able to make a coal, oil or gas fired power plant out of their own sources which leaves a advanced factory trying to keep up with the demand for fusion plant spares as more of the advanced factories get nuked.  Each world would also have to build the industries that would lead to a nuclear reactor; the threshold for hydro or c/o/g plants is a lot lower.

Fossil plants are easier and cheaper, and I suspect they'd be the main source of power for any place out in the sticks. But fission plants are still 1930s technology, and the thorium variety doesn't even require a uranium enrichment program. Any large city that can't maintain a fusion plant has almost certainly switched to fission.

Even on planets where the economy doesn't support fission energy, as I mentioned previously, fuel cells are convenient sources of pure water and there are no technological hurdles preventing a planet with abundant oceans from using solar concentrators and fuel cells together as an effectively unlimited source of drinkable water--except in the case of places that are limited to 19th-century tech like New St Andrews.
Half the fun of BattleTech is the mental gymnastics required to scientifically rationalize design choices made decades ago entirely based on the Rule of Cool.

The other half is a first-turn AC/2 shot TAC to your gyro that causes your Atlas to fall and smash its own cockpit... wait, I said fun didn't I?

Jellico

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Re: Fuel Cell vs ICE
« Reply #56 on: 01 February 2019, 00:58:24 »
Heck. I'd be looking at solar or wind power for power generation even in the sticks. Battletech tech lasts for centuries. Importing a generator may well be comparable in cost to designing and implementing an ICE plant. Maintenance is then a magic number but it could well be negligible.

I have said before the US writers are too far removed from when the US was a 3rd rate power which imported most of its advanced tech. Too often the Periphery minors are treated as little games of Civilization where you have to build all your own stuff. In reality minors are often dependent on imports to a shocking level.

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Re: Fuel Cell vs ICE
« Reply #57 on: 01 February 2019, 10:14:14 »
Heck. I'd be looking at solar or wind power for power generation even in the sticks. Battletech tech lasts for centuries. Importing a generator may well be comparable in cost to designing and implementing an ICE plant. Maintenance is then a magic number but it could well be negligible.

I have said before the US writers are too far removed from when the US was a 3rd rate power which imported most of its advanced tech. Too often the Periphery minors are treated as little games of Civilization where you have to build all your own stuff. In reality minors are often dependent on imports to a shocking level.

I suspect that part of the reason why everyone wants to build their own stuff is because the Star League worlds on the Periphery and other backwaters who were depending mostly on imported tech backslid badly or died out during the Succession Wars.


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Re: Fuel Cell vs ICE
« Reply #58 on: 01 February 2019, 12:17:29 »
Who says a House Lord has that kind of authority? They're not interstellar dictators. If a duke or earl wants a nuclear program in his own sub-realm, that's his business under the feudal code. The House Lord isn't likely to start a civil war over it since there are bigger fish to fry. And if anyone is that afraid of nuclear weapons, thorium breeder reactors are a safer, difficult-to-weaponize option.

But again, nobody freaks out over random civilians having their own DropShips because using them as relativistic weapons is just not the done thing, despite a Union that has expended all its fuel burning at a planet being deadlier than Earth's entire present-day nuclear arsenal combined. The trouble and expense of a secret nuclear weapons program just isn't worth it even for terrorists. Even a K-1 DropShuttle has the potential to be a multi-gigaton impactor.

Fossil plants are easier and cheaper, and I suspect they'd be the main source of power for any place out in the sticks. But fission plants are still 1930s technology, and the thorium variety doesn't even require a uranium enrichment program. Any large city that can't maintain a fusion plant has almost certainly switched to fission.

Even on planets where the economy doesn't support fission energy, as I mentioned previously, fuel cells are convenient sources of pure water and there are no technological hurdles preventing a planet with abundant oceans from using solar concentrators and fuel cells together as an effectively unlimited source of drinkable water--except in the case of places that are limited to 19th-century tech like New St Andrews.

Because smacking a planet with a dropship has implications for those who are still on the planet and its something that is obvious as it happens.  Pulling a Atomic Annie and walking the bomb to near the target is not something obvious and is a threat that does not have to change the whole world- size dependent of course.  Its a kind of defensive measure that allows a planet to thumb their nose at the House Lord- land your RCT, I DARE YOU.  Restricting NBC, like artillery and ASF, is one of those setting things that makes ground armies in general and mech in particular king.  Its not like we are talking about some US state building a new nuke plant.  You are talking about planets involved with a continuing tech loss, or already hammered by it so they will have to get the specialized tools to build the tools they need to make the tools that gives them the piles, reactors, and such to get the energy/weapon.

When they have to import tech/parts rather than build it up from scratch in their own fief, then that gives the House Lord a lot more ways to slow things down- just like Sun Tzu did to the Taurians in the Trinity Alliance.

Again, end of 2SW and through the 3SW you are going to have to get the technology to build up to the infrastructure it takes to support a nuclear program- and you said the SL considered it 'dead' technology.  While it maybe 1930s tech its not something post-Star League worlds will have experience with or have the infrastructure in place to crank out the components needed.  You may know the general theory behind the processes, but can you sit down and build your own coal fired boiler to motive power?  or more complicated, electricity?  Its like when the Iowa had a 16" gun malfunction in '89.  We knew the specs, we knew the how, but the factories that had built the gun tubes, breechs, blocks and other parts for its operation had been shut down for decades- so even before that the parts had to be custom made which made the costs astronomical.  Heck, we have not built a new non-ship/military reactor here in the US until 2016, and it was nearly 20 years before that for the last one . . . which had a decade or more from the previous one.  This also gets into the economies of scale, which also leads to the planet wanting it to import- to go somewhere that can produce it.
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Atarlost

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Re: Fuel Cell vs ICE
« Reply #59 on: 01 February 2019, 18:53:39 »
Fossil plants are easier and cheaper, and I suspect they'd be the main source of power for any place out in the sticks. But fission plants are still 1930s technology, and the thorium variety doesn't even require a uranium enrichment program. Any large city that can't maintain a fusion plant has almost certainly switched to fission.

The trouble is that they presume fossil fuels exist on the planet.  You need to start with a lot of life, which many planets will never have had.  Then you need lots of it to die all at once and pile, then it needs to get buried before it decomposes.  Add time heat and pressure over geologic time and you've got oil, but the earlier steps are less reliable. 

Some worlds never had dense enough biospheres.  Others haven't had a mass extinction.  Or just haven't had one that produced oil fields.  Not all of Earth's seem to have.  Carbon sequestration reduces the potential density of the biosphere because life is made of carbon (or at least any life that can produce fossil fuels is).  Hesperus seems to be about as dense with life as possible so it probably can't have had a mass extinction that produced oil.  That means you can probably go for biofuels, but it still not going to be as economical as other methods. 

Most of the time these no oil planets are going to be the poor ones.  Not only is it a handy bootstrapping fuel but it's used in chemical industries.  Tharkad's going to have oil but be prosperous enough to not need to burn it while poor Trellwan desperately needs cheap power but doesn't have oil. 

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Re: Fuel Cell vs ICE
« Reply #60 on: 01 February 2019, 19:13:21 »
The trouble is that they presume fossil fuels exist on the planet.  You need to start with a lot of life, which many planets will never have had.  Then you need lots of it to die all at once and pile, then it needs to get buried before it decomposes.  Add time heat and pressure over geologic time and you've got oil, but the earlier steps are less reliable. 

Some worlds never had dense enough biospheres.  Others haven't had a mass extinction.  Or just haven't had one that produced oil fields.  Not all of Earth's seem to have.  Carbon sequestration reduces the potential density of the biosphere because life is made of carbon (or at least any life that can produce fossil fuels is).  Hesperus seems to be about as dense with life as possible so it probably can't have had a mass extinction that produced oil.  That means you can probably go for biofuels, but it still not going to be as economical as other methods. 

Most of the time these no oil planets are going to be the poor ones.  Not only is it a handy bootstrapping fuel but it's used in chemical industries.  Tharkad's going to have oil but be prosperous enough to not need to burn it while poor Trellwan desperately needs cheap power but doesn't have oil.

The term Internal Combustion Engine doesn't neccesarily mean fossil fuel powered. You can use basically anything that burns, even low grade alcohol like hydrogen peroxide to fuel an engine. They aren't very efficient compared to high grade gas, but you can definitely use low grade fuel to fuel and run an engine that doesn't require "oil" to produce.

Even then, you can probably import fuel if you really needed to.

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Re: Fuel Cell vs ICE
« Reply #61 on: 01 February 2019, 20:04:28 »
ICE engines don't need petroleum.  Other chemicals, like ethanol, can be used instead.

If the planet can support life, you can probably grow something that can be converted into ethanol.

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Re: Fuel Cell vs ICE
« Reply #62 on: 02 February 2019, 12:34:19 »
The term Internal Combustion Engine doesn't neccesarily mean fossil fuel powered. You can use basically anything that burns, even low grade alcohol like hydrogen peroxide to fuel an engine. They aren't very efficient compared to high grade gas, but you can definitely use low grade fuel to fuel and run an engine that doesn't require "oil" to produce.

Even then, you can probably import fuel if you really needed to.

This could be a useful secondary source of income for any unit with a fusion reactor.  As long as they are provided with enough hydrogen, they can provide electrical energy for the locals to produce various ICE fuel with.  Ammonia might be a good one for the locals to make, using an advanced version of the Haber Process.  You won't get the same energy per weight of fuel (ammonia is only ~40% as much as gasoline), but ammonia only needs Nitrogen and hydrogen, while gasoline needs fossil fuels.  Ammonia only has ~60% the fuel density of ethanol.

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Re: Fuel Cell vs ICE
« Reply #63 on: 02 February 2019, 14:53:43 »
The term Internal Combustion Engine doesn't neccesarily mean fossil fuel powered. You can use basically anything that burns, even low grade alcohol like hydrogen peroxide to fuel an engine. They aren't very efficient compared to high grade gas, but you can definitely use low grade fuel to fuel and run an engine that doesn't require "oil" to produce.

Not for power production you can't.  Alcohol and biodiesel work for energy transport, though you're going to suffer the same range penalties as fuel cells if you try to use the former.  They don't work for energy production, though.  They're just staggeringly inefficient methods of solar collection.  If you use the same land you were using to grow fuel crops to build mirror array and heat engine style solar plants you get more power out. 

Also, hydrogen peroxide is not alcohol or even fuel.  It's an oxidizer completely redundant if you have a breathable atmosphere. 

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Re: Fuel Cell vs ICE
« Reply #64 on: 02 February 2019, 17:59:05 »
Not for power production you can't.  Alcohol and biodiesel work for energy transport, though you're going to suffer the same range penalties as fuel cells if you try to use the former.  They don't work for energy production, though.  They're just staggeringly inefficient methods of solar collection.  If you use the same land you were using to grow fuel crops to build mirror array and heat engine style solar plants you get more power out. 

Also, hydrogen peroxide is not alcohol or even fuel.  It's an oxidizer completely redundant if you have a breathable atmosphere.
Err... Humanity's been using biofuel for energy production for millennia before we figured out fossil fuels. It most certainly works for a high-tech society as long as the population density is low enough (because otherwise you won't have enough space to grow fuel - which is the problem IRL).

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Re: Fuel Cell vs ICE
« Reply #65 on: 03 February 2019, 16:06:33 »
In general, I assume non-fission energy sources are plentiful and easy to access. IIRC thee is no mention of energy problems anywhere in the background... Only when someone comes and disrupts your supply via a raid, but then, that is what the raid was about after all. Or as cover for something else

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Re: Fuel Cell vs ICE
« Reply #66 on: 03 February 2019, 23:12:54 »
ICE engines don't need petroleum.  Other chemicals, like ethanol, can be used instead.

If the planet can support life, you can probably grow something that can be converted into ethanol.

Wouldn't waste my time, grow an oil crop and get it running in a Diesel Type application, less loss due to conversion and processing.
Saying that because the equipment isn't up-to-the-minute, bleeding-edge tech therefore not a threat is like saying an M2 Browning isn't dangerous to modern infantry because it is 100 years old.

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Re: Fuel Cell vs ICE
« Reply #67 on: 03 February 2019, 23:32:18 »
Wouldn't waste my time, grow an oil crop and get it running in a Diesel Type application, less loss due to conversion and processing.

Sure, I was just using an example.  Biodiesel would be more efficient but it depends on what grows best.

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Re: Fuel Cell vs ICE
« Reply #68 on: 08 March 2019, 10:16:54 »
Battletech was written in the 80s as such military deuce and a halfs had multi fuel ICE engines . So in battletech I always thought any non aviation chassis used whatever fuel was most available in a motar pool . The ICE engine was configured to use that fuel be it Gasoline , Desil , Alcohol , or Natural Gas . Aviation gas normally is used to propell units in the air Alcohol my not have enough BTU to get the lift needed to fly . Since I am normally doing the defence the operational radius of fuel cell helpas mostly

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Re: Fuel Cell vs ICE
« Reply #69 on: 09 March 2019, 01:49:12 »
Also a question re fuel cells.

Can you put a gauss rifle on a fuel celled vehicle or do you need a fusion engine for them?
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Re: Fuel Cell vs ICE
« Reply #70 on: 09 March 2019, 02:08:15 »
Standard Gauss Rifles work with Fuel Cell engines.  Fusion is only required for HGRs and iHGRs.

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AdmiralObvious

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Re: Fuel Cell vs ICE
« Reply #71 on: 09 March 2019, 03:55:52 »
The standard gauss rifle comes with what's essentially a power amplifier already built in. The difference between it and the HGR series is that you need a pretty big series of capacitors to charge a heavy gauss.

You probably could still fire one without a fusion engine, you'd just have to wait a few minutes to hours for the capacitor to charge enough to actually fire again. Unlike the current ten second refire time.

marauder648

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Re: Fuel Cell vs ICE
« Reply #72 on: 09 March 2019, 04:46:06 »
Cheers :) Thanks for the clarification :)
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Talen5000

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Re: Fuel Cell vs ICE
« Reply #73 on: 09 March 2019, 07:59:37 »
Personally when I first started designing with FCs they struck me as Clantech ICEs.

More advanced tech. Lighter. Less range.

Of course they haven't been used that way but I feel that you can make an argument that FCs should replace most of the ICEs in Clan service right down to the very low civilian end. You could say the same for the Star League given what they have been fluffed to have been running in civilian vehicles.

No Clan vehicle should be using ICE. They don't like waste and don't even do much extraction of oil. Unfortunately l, I don't think rules for fuel cells were written when Clan vehicles were added.
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Terrace

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Re: Fuel Cell vs ICE
« Reply #74 on: 09 March 2019, 11:26:08 »
No Clan vehicle should be using ICE. They don't like waste and don't even do much extraction of oil. Unfortunately l, I don't think rules for fuel cells were written when Clan vehicles were added.

That's probably why so many Clan vehicles use fusion engines.

marauder648

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Re: Fuel Cell vs ICE
« Reply #75 on: 10 March 2019, 04:52:00 »
I doubt Clan ICE engines would use oil, they'd probably be a multi-fuel engine and would burn something like alcholo or something.
Ghost Bears: Cute and cuddly. Until you remember its a BLOODY BEAR!

AdmiralObvious

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Re: Fuel Cell vs ICE
« Reply #76 on: 10 March 2019, 05:33:14 »
The ICE in general is pretty wasteful compared to most other engine types. As said earlier, what's going for them is their simplicity to maintain.

The difference I guess, and reason they aren't totally phased out in the clans is because you can burn almost anything in them. That makes them extremely useful for utility purposes like support vehicles and industrial mechs. I can see why they'd use a few on combat vehicles too, but I think the overwhelming majority of Clan combat vehicles use fusion, except for maybe the Hells Horses. They actually went out of their way to make chemical lasers relevant because they didn't want to use fusion engines, and didnt want to have to add capacitor banks to every tank they make.

marauder648

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Re: Fuel Cell vs ICE
« Reply #77 on: 10 March 2019, 06:24:36 »
I see it the other way round with Chemical lasers.  They are almost uniformly seen on very much second line or defensive units and were designed at a time when resources were tight.  Better to pull out those fusion engines from the tanks, slap an Fuel cell into it and use Chemical lasers instead of normal lasers and the like on those 2nd line vehicles and put their energy weapons and fusion engines to better use elsewhere.
Ghost Bears: Cute and cuddly. Until you remember its a BLOODY BEAR!