Power system of Antenna Relays

[kithylin]

Okay something I've been wondering about KSP I would like for someone to please to answer for me.

I know for example: I have a space ship and I collect a bunch of science, extend it's antenna and send home. And while it's transmitting, it chews through the on-board electricpower supply.

But what I don't know I would like you to clarify: What if I bounce that much science through a relay satellite through the network. Does the act of relaying the science data through the network drain the same amount of power (compared to transmitting it from the ship as described above) through each relay's on-board electricpower as it passes through?

Will the science stop and transmit much slower if the relay runs out of power and sucks it back through it's solar panels?

I have so far been over-building my relays with something around 8000 - 12000 electricpower worth of batteries. But I'm wondering.. to be more efficent at things, do I need that much? Or can I build my relays with say just 100-300 electric power and will they still be able to bounce data through the network without slowing down?

 

EDIT: Vanilla game, no mods other than MechJeb. 

Edited July 27, 2019 by kithylin

[overkill13]

I haven't exactly tested, but I've never noticed the EC being depleted on my relays. 

Given that a solar mining rig on the night side of the mun will keep on pumping out ore/fuel even while it's shaded for 19+ hours so long as you do not switch to it, I doubt KSP is coded for unloaded vessel power consumption from relaying data.  It would also conflict with the fact that power does not generate on unloaded vessels, so a relay in the sun would never recharge after being depleted by data transmission until you switched to flying it.

[Gargamel]

No, I believe they do not use any power if they are not in focus. 

Moved to Gameplay Questions. 

[kithylin]

Thank you all for answering. So I can build much smaller relays now which will make deploying them easier.

[AHHans]

A quote from the documentation of the Kerbalism mod: "Contrary to popular belief, the observable universe is not a sphere of a 3km radius centered around the active vessel." (here) But in KSP that is exactly the case! Everything further than 3km from the active vessel doesn't really exist, or you could say, that they exist in a state of non-existence. But before I get too philosophical, back to the gameplay consequences: in stock KSP no electricity is ever added or drained to unloaded (= not simulated, i.e. far from the current vessel) vessels. So if you leave a vessel on low ECs because you just made a bunch of maneuvers and drained the batteries, it will not have recharged even if it spent ages with its solar panels in the sun and nothing running that drains ECs. But also if you have a vessel with a continuous power drain - like the research lab, or and ISRU system - and not enough power generation to fulfill that need, as long as it had some ECs left in the batteries when it is unloaded (e.g. because you go back to the space center)  it will "keep working"(*) until the vessel is loaded the next time. Which is considered a kind of cheat by most people.

From this follows, that: no, relays don't need electricity to relay science.

P.S. (*) They don't really work while they are not loaded. But when they are loaded the next time then the system computes how much it would have done (science generated for the lab, or ore mined/converted for an ISRU) since the last time they were visited.