Unit of "ElectricCharge"

[1096bimu]

The small solar panel gives 0.75 units of electric charge per second. I don't know its area, assuming its length and width are a and b, we have:

a+2b=3.4a=1.25

2b=2.4a=1.25

b=0.625

a=0.521

Area= 0.326m^2

Our sun's output in orbit around Earth would be around 1.3kJ/m^2/s.

A panel this size would be receiving 0.42kJ/s

Assuming its efficiency to be at 20%, energy output would be 85J/s

And we have, 1 unit of ElectricCharge roughly equal to 113, or about 100 Joules of energy if we were to take a guess at the developers' original intent.

However, the Z-400 battery weighing at 20 kilos, only has 400 units, where as a Lithium-ion battery would have 16,000,000 joules or 160,000 electric charge.

The stock lights, they only use a few units of ElectriCharge per minute, where as a real light of about 100 watts would be using 1 per second.

Edited May 28, 2013 by 1096bimu

[Michael Kim]

So what is your point here?

Our sun's output in orbit around Earth would be around 1.3kJ/m^2/s.

It's Kerbal.

[iamaphazael]

There have been some heated debates over what units we should use to talk about the electrical energy in the game. The thing is that the way "ElectricCharge" functions in the game is not at all an accurate representation of how electricity works in the real world, and so any attempt to try to apply actual principles of electrical engineering to the system in the game is destined to end in pain. It's best to just think of it as a different flavor of fuel, because that's how the game treats it.

Maybe someday Squad will implement a more realistic electricity model, but it doesn't seem like they're particularly interested in going in that direction, and personally, I don't think it's needed.

[HoY]

I call them kW and kWh just to call then something that's not "unit"

[Specialist290]

I typically call them "kwonks" (for Kilowatts on Kerbin), but that's just me.

[AlexanderB]

The solar panels ingame are just way overpowered, compared to real life..

[m4v]

The small solar panel gives 0.75 units of electric charge per second.

If you take the ElectricCharge unit literally and we believe that the devs didn't call it "electric charge" just because then it should be measured in Coulombs, that translates nicely all the sources and sinks of electricity into Amperes (1A is 1C/s, ie, the small solar panel gives 0.75A or 750mA, the spotlights consume 40mA, etc) but then the batteries ratings get awfully low like Z-400 getting 0.111Ah or 111mAh, which is like 10 times worse than a typical AA alkaline battery.

Also "electric charge per sec" isn't energy, you can't compare it with joules, for talk about energy we need to know the potential or voltage involved.

I suppose that electricity in KSP is so disconnected from reality that we can't say what it is

Edited June 4, 2013 by m4v

[silent_prtoagonist]

I like to think of 1 unit of "electric charge" as being equal to 1 MJ, based on the ion thruster.

The PB-ION produces 500 N of thrust with an exhaust velocity of 41,202 m/s (insert rant about the units of Isp here), and draws 14.548 ec/s (according to the wiki).

Thrust power for a reaction engine is:

thrust power = 1/2*thrust*exhaust velocity = 0.5*500N*41202m/s = 10.3E6 W

Assuming it's drawing 14.548E6 W of electrical power, this corresponds to an efficiency of 10.3/14.548 = 70.8%, which seems reasonable.

Interestingly, 1 MJ is also equal to about 240 food calories. Thus, in order to reduce confusion about charge vs. power, I hereby recommend rebranding the unit of electrical power in KSP as "snacks."

[Aghanim]

I like to think of 1 unit of "electric charge" as being equal to 1 MJ, based on the ion thruster.

The PB-ION produces 500 N of thrust with an exhaust velocity of 41,202 m/s (insert rant about the units of Isp here), and draws 14.548 ec/s (according to the wiki).

Thrust power for a reaction engine is:

thrust power = 1/2*thrust*exhaust velocity = 0.5*500N*41202m/s = 10.3E6 W

Assuming it's drawing 14.548E6 W of electrical power, this corresponds to an efficiency of 10.3/14.548 = 70.8%, which seems reasonable.

Interestingly, 1 MJ is also equal to about 240 food calories. Thus, in order to reduce confusion about charge vs. power, I hereby recommend rebranding the unit of electrical power in KSP as "snacks."

But KSP Interstellar....

[SunJumper]

I like to think of 1 unit of "electric charge" as being equal to 1 MJ, based on the ion thruster.

The PB-ION produces 500 N of thrust with an exhaust velocity of 41,202 m/s (insert rant about the units of Isp here), and draws 14.548 ec/s (according to the wiki).

Thrust power for a reaction engine is:

thrust power = 1/2*thrust*exhaust velocity = 0.5*500N*41202m/s = 10.3E6 W

Assuming it's drawing 14.548E6 W of electrical power, this corresponds to an efficiency of 10.3/14.548 = 70.8%, which seems reasonable.

Interestingly, 1 MJ is also equal to about 240 food calories. Thus, in order to reduce confusion about charge vs. power, I hereby recommend rebranding the unit of electrical power in KSP as "snacks."

I prefer the unit Yoda-Second (170 Yoda-Seconds to an electric charge unit). Source

[Andrew Hansen]

I personally think the batteries in Kerbal Space Program need to become 100x as heavy (they're so light right now) and be used 100x as slowly. Why used 100x as slowly? It's the same as saying the batteries have 100x as much charge, but without dealing with such huge numbers.

Right now you can't even drive up a hill on the Mun on batteries. If you lose solar power in a shadow, you'll have to wait for a long time before driving again.