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Make electricity make sense


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On 7/2/2016 at 5:27 PM, Corona688 said:

As close as I can guess, based on the power output of fuel cells relative to rocket engines on the same fuel, 1 "unit" of electricity is about 40 joules.  At 0.04 units per second, that makes the mk1 illuminator a one-watt bulb.

No matter what units you put on it, electricity's not going to make sense right now.

I don't know if we really need to worry about volts, amps and watt-hours.  If you take voltage out of the equation - which you mostly do with chemical cells, where 1.2v is full and 1.1v is flat -- everything's just energy in the end.

Edited by Corona688
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Have to remind yourself here how Joule is represented as measure unit. Ws is just one of possible representation of it. But, since it actualy very small amount of energy, more apropriate unit should be kWh.

As for usage in form of electricity, no special need to overcomplicate things with voltages and ampers, as power consumed from power source (battery/solar panels) can be presented in various ways if you know resistance of load attached to power source. If we mark resistance as R, voltage as U current as I and power as P most of you know from school how it is calculated:

P = U * I

R = U / I

Therefore

P = I2 * R

or

P = U2 / R

Therefore, for game usage should be enough to have Power in watts or kilowatts for both, power sources and power consumers. Depending for how long it is plugged in, it will consume as much kWh stored energy from batteries. Solar panel could be rated in kilowats for maximum exposure of 100% to sunlight and for how long it get light it would fill energy in batteries.

Curently, in game we have confusing numbers, some fictional EC/min in one item and EC/s on other item. If one of KSP goals is to be educative game, kW and kWh are more apropriate units to be used for electricity parts, especialy as it follow to good degree International System of Units and SI derived units.

Batteries in real life is more complicated, for example as stored energy in battery depleats voltage drops, but even nearly empty battery can have significantly high voltage, but as soon as you plug in something on such battery, it no longer can provide enough current and because of that not enough power that some load attached needs. That is whole another topic for itself that is not easy to explain in few sentances.

Using SI units instead of fictional "EC" would lead to easier balancing of all items in game.

Edited by kcs123
typo corrected
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5 minutes ago, Triston777 said:

Not just that issue but let's not forget that electric engines are terrible to use in-game? My question is why is it they do so little?

You talking about the ion engine?

It's supposed to be low thrust, high efficiency.

Really, it's mainly for probes and very small craft, and only in space; trying to move something heavy or in atmo with it is just silly.

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21 hours ago, Triston777 said:

Not just that issue but let's not forget that electric engines are terrible to use in-game? My question is why is it they do so little?

In vacuum conditions, it can push a grand piano up to 60mph in 5 seconds flat.  That is not under-powered.  Your spacecraft are just huge.

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14 hours ago, Corona688 said:

In vacuum conditions, it can push a grand piano up to 60mph in 5 seconds flat.  That is not under-powered.  Your spacecraft are just huge.

 

This has little meaning without context on how big the engine is in comparison.

 

If the engine's the size of a pencil sharpener, that's absurdly impressive.  If the engine is the size of a school bus, that's irrecoverably pathetic.

 

The real problem with ion engines is they operate in a manner not really conducive to gameplay.  Gameplay events must be done in minutes to keep the player entertained.  Ion engines only really shine when they're burning for HOURS or even DAYS at a time.  This is made more troublesome with Kerbal's reduced system scale.  Orbits are tighter, maneuver windows are smaller.  So an ion engine is stuck working even harder.

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Well, I am pretty sure that complicating things with volts and amps on batteries, changing if connected in series or parallel, will NOT make EC make sense to most people.

What would, is KSP adding up your usage and presenting it as a number, and also your generation and presenting that as another number, possibly with a third number showing if you are generating too much, enough, or not enough.

The way I would like units of measurement to make sense is to have the same timescale used for every part. Either per second, per hour, or per day. All are fine but choose one, not a mix and match of whichever units you decided to use when you wrote the description.

Also, how am I supposed to know if I am making enough power when parts do not tell me usage/generation if I right click in the VAB or in flight? Should I be right clicking on all the parts one by one in the parts list then adding up the various amounts, so much in EC/s, so much in EC/hr, multiply one to get numbers that make sense together then add them up.

Then repeat the whole process for generation?

Idiotic. Minimalism taken to the point of being unusable.

Without going into volts and amps etc there are some more basic, obvious, ways to deal with EC could do with being implemented.

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On 11/25/2017 at 2:15 PM, Triston777 said:

Not just that issue but let's not forget that electric engines are terrible to use in-game? My question is why is it they do so little?

They actually do a lot more than real-life electric engines.  It's inherent in the technology, they don't have a lot of thrust

3 hours ago, John FX said:

What would, is KSP adding up your usage and presenting it as a number, and also your generation and presenting that as another number, possibly with a third number showing if you are generating too much, enough, or not enough.

The

Oh, you mean, hmmmm, Fusebox or AmpYear?

On 11/23/2017 at 1:58 PM, Corona688 said:

I don't know if we really need to worry about volts, amps and watt-hours.  If you take voltage out of the equation - which you mostly do with chemical cells, where 1.2v is full and 1.1v is flat -- everything's just energy in the end

Depends on the chemical:

Lead-Acid: 1.9v - 2.1v

Ni-cad: 1.3v - 1.5v

Lithium-Polymer: 3.6v - 4.2v

 

etc

 

Edited by linuxgurugamer
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11 minutes ago, linuxgurugamer said:

Oh, you mean, hmmmm, Fusebox or AmpYear?

*sigh*

If you had read the thread then you would have read the post where I relate how neither of them are suitable and why...

To save you time, if you use mods then fusebox picks up on so few of them it is worse than nothing, if you use mods then (in my case right now) mod interaction means if Ampyear is installed, my root part cannot be moved by gravity or thrust, a bit of a problem if you want your craft to go anywhere. If you do not use mods then a mod is not a solution for your problem.

As such, `there`s a mod for that`, especially after I have explained why I am calling for a stock solution and have explained specifically why neither of those mods is good enough, is more trite than usual.

Please read the thread to stop me having to say this too often...

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9 hours ago, AdmiralTigerclaw said:

This has little meaning without context on how big the engine is in comparison.

Its an ION DRIVE.  An ion drive with 2 kilo-newtons thrust is absurd.

9 hours ago, AdmiralTigerclaw said:

The real problem with ion engines is they operate in a manner not really conducive to gameplay.

Which is why they have a 2 kilo-newtons thrust, not a more technically reasonable 50 milli-newtons.

9 hours ago, AdmiralTigerclaw said:

Ion engines only really shine when they're burning for HOURS or even DAYS at a time.

...or when you build small.  Not everything has to be a kerbal 10 ton monstrosity.

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2 hours ago, Corona688 said:

...or when you build small.  Not everything has to be a kerbal 10 ton monstrosity.

The problem is that it may still take days to complete a burn, especially large ones. And some players just don't have the patience to plan and execute gravity assists. (I know I'm not :P) And besides, whats the fun in something that isn't  a kerbal monstrosity? :wink: 

 

Edit: Misinterpreted post. Please move on.

Edited by Gyrfalcon5
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Misinterpreted, fair enough, but it's still worth pointing out that the small xenon tanks only have 20 minutes of xenon fuel, not 3 hours.

6 hours ago, linuxgurugamer said:

They actually do a lot more than real-life electric engines.  It's inherent in the technology, they don't have a lot of thrust

Oh, you mean, hmmmm, Fusebox or AmpYear?

Depends on the chemical:

Lead-Acid: 1.9v - 2.1v

Ni-cad: 1.3v - 1.5v

Lithium-Polymer: 3.6v - 4.2v

etc

You get my point though - the voltage only changes a small percentage between full and discharged.  If the voltage significantly drops, the battery's dead.  You could model it as a uniform voltage and an energy level below which everything stops.

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3 minutes ago, Corona688 said:

Misinterpreted, fair enough, but it's still worth pointing out that the small xenon tanks only have 20 minutes of xenon fuel, not 3 hours.

You get my point though - the voltage only changes a small percentage between full and discharged.  If the voltage significantly drops, the battery's dead.  You could model it as a uniform voltage and an energy level below which everything stops.

But why bother? End result is no Ec, whether it is because of lo voltage or something else

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6 minutes ago, linuxgurugamer said:

But why bother? End result is no Ec, whether it is because of lo voltage or something else

Because we already have it, more or less.  It just needs a tiny bit more foundation so we can start defining consumption in watts, batteries in kilowatt-hours, and balance everything out so we have 1kwh power, 50w lights, 1000/50 = 20 hours, done.

Edited by Corona688
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As I understand, electricity is abstracted in the following ways:

First, batteries can charge and decharge arbitrarily fast, when real-world batteries don't do that. Power is not an issue, just energy.

Second, voltage is completely abstracted away. Between the first two points, batteries are magic energy storage and delivery devices.

Third, real-world equipment decays with time, whereas KSP batteries fail primarily when you misjudge your Mun landing.

Fourth, KSP batteries appear to have very poor energy/mass density. I run with 1 EC being approximately 1 kJ of energy. KSP batteries thus store 20 kJ/kg, embarassing next to the 360-950 kJ/kg energy density of lithium-ion batteries. Even the RO assumption of 1 EC = 1 kWh brings KSP batteries to a whopping 72 kJ/kg.

 

So, the question is: which of these abstractions are sound for gameplay?

On the first: I could see this becoming a togglable difficulty option. It'd break legacy craft if always turned on, but I could see a max charge/decharge speed, though it'd take a bit of fiddling, since right now stock resources are consumed from storage as fast as the consumers need them.

On the second: I agree with this abstraction. Not all that many players are going to want to play Electrical Engineering: The Game.

On the third: this can be lumped in with "part failures in general", to which I'd say "if Squad had infinite code monkeys, sure, but I'm fine leaving this to the modders".

On the fourth: it's mostly an internal game balance issue that mostly becomes a question when you start to do large-scale modding, and I can't exactly comment on the balance of the stock game when I haven't played the stock game seriously in years.

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10 hours ago, Starman4308 said:

Not all that many players are going to want to play Electrical Engineering: The Game.

True. Next you're gonna tell me there's weirdos out there that want actual orbital mechanics in their space game, and that entire forums will be filled with discussions about dV, TWR, and rocket equations... :D

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On 11/21/2017 at 10:11 AM, Aegolius13 said:

I don't disagree,  but this seems maybe less important than the other units you mention.  In particular,  it's helpful to have meters, kg, etc. to be able to do conversions (i.e, acceleration from force and mass,  the rocket equation,  etc.).  Electricity,  though,  kind of stands on its own and does not interact with the other stats in the same way.   

For the record,  I think the official EC unit is Pirate-Ninjas.

I LOVE YOU FOR QUOTING MARK WATNEY FROM THE MARTIAN

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Some other things were not mentioned previously, while it fine to use kWh for battery as power source, there is missing info of peek power that some power source can give. It is not same if battery or other power source of 10 kWh provide 10kW trough one hour or 1kW trough 10 hours. In real life it is usualy max current on battery declaration that gives you info what is max battery power.

For power source like solar panel or RTG there should be info about peek power. Items that use electricity or load should also need info about power that is needed each second for normal operation.
All that if it is necessary to avoid more complex system that include voltages and amperes.

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12 hours ago, Starman4308 said:

As I understand, electricity is abstracted in the following ways:

First, batteries can charge and decharge arbitrarily fast, when real-world batteries don't do that. Power is not an issue, just energy.

Batteries are pretty good at dis-charging.  A car starter pulls a large chunk of the battery's capacity in seconds.  I agree that recharging should be more hassle than it is.

12 hours ago, Starman4308 said:

Fourth, KSP batteries appear to have very poor energy/mass density. I run with 1 EC being approximately 1 kJ of energy. KSP batteries thus store 20 kJ/kg, embarassing next to the 360-950 kJ/kg energy density of lithium-ion batteries. Even the RO assumption of 1 EC = 1 kWh brings KSP batteries to a whopping 72 kJ/kg.

You might pick one thing and say "therefore 1EC=1KJ" but electricity is utterly ad-hoc right now.

  • If you look at the electricity consumption of the Communotron 16 and wave a rubber chicken over some physics facts, each unit of EC might be about 10 joules.
  • If you look at the fuel consumption rate of fuel cells vs engines, each unit of EC may be about 40 joules (with a very large margin of error).
  • If you assume the MK1 Illuminator is a 100W bulb(don't tell me its a LED, it has warmup!), each unit of power is about 5 kilojoules.
  • If you look at the electricity consumption of ion engines, each unit of EC is about 30 kilojoules at minimum, probably many times more!

I'm inclined to think the lower end of the scale is right, since that's more reasonable compared to in-game solar panels.  But as the game was added on, all sense of scale was lost.

 

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On 11/21/2017 at 10:11 AM, Aegolius13 said:

Electricity,  though,  kind of stands on its own and does not interact with the other stats in the same way.

Electricity has been directly tied to in-game stats ever since they added electric parts for moving things, heating things, cooling things, and generating power from fuel.  The only magic left is lamps.

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