is it possible to make an engne that runs on pure electricity?

[Capt. Hunt]

that is different, as I recall, it worked on the same principle as the NERVA, using radiation to heat the fuel.

[MarvinKitFox]

Light is massless so option 1 would not work. And if I understand option 2 correctly, something like that is already being worked on.

Light (photons) have no rest mass, but an energized photon is a quite effective conveyor of momentum.

See: http://en.wikipedia.org/wiki/Radiation_pressure

And, it it quite possible to generate huge amounts of photons, with no loss to your spacecraft other than the energy needed to create to photons. no mass loss needed, unless you delve into the obscure depths of e=mc2

Unfortunately, the energy needs for even one newton of thrust is... massive. For example, the full blast of solar light in earth orbit provides a thrust of 9 micro-newton per square meter. While "using" about 1350watt.

Disregarding conversion efficiencies, you would need 150 megawatt of electrical power to generate 1 newton of thrust.

[Bloodbunny]

that is different, as I recall, it worked on the same principle as the NERVA, using radiation to heat the fuel.

Not the same as a NERVA to be sure, the nuclear jets didn't use any liquid fuel. Needing liquid fuel would defeat the purpose of having a nuclear powered aircraft. http://en.wikipedia.org/wiki/General_Electric_J47#The_nuclear-powered_X39

[radonek]

Not the same as a NERVA to be sure, the nuclear jets didn't use any liquid fuel. Needing liquid fuel would defeat the purpose of having a nuclear powered aircraft. http://en.wikipedia.org/wiki/General_Electric_J47#The_nuclear-powered_X39

Same thing. Just dont need to carry "fuel" around since air tends to be around aircraft, but it need some form of reaction mass. NERVA have to carry reaction mass outside atmosphere, but create thrust via same principle.

[CoolBeer]

As far as I recall it's not possible to make a pure electrical rocket in KSP, you can however have an engine with a moduleGenerator module that takes electrical charge and converts it into fuel that you can burn.

It does not have any basis in reality though(which is a no-go for myself).

(And yes, the nuclear jet engine basically sucked in air, compressed it, passed it over a reactor to heat it up(and therefore expand) before throwing it out the back. So yes, air was the reaction mass. *SOURCE*).

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Kolbjorn

Edited April 11, 2014 by CoolBeer
added a word

[SirusKing]

The resulting laser output is probably enough to vaporize the very ground from which it launches from (and blind about everyone in the vicinity).

Have you heard of the Kzinti Lesson?

[TheScareCake!]

Its even created now! There are drones who use electric propellers and solar panels.

[Sandermatt]

Edit: way too slow

[Slow Dog]

KSP Interstellar has a fuelless drive that supposedly uses quantum fluctuations.

Have you heard of the Kzinti Lesson?

Indeed. Niven's also described the Puppetteer drives, which use Neutrinos (which thus pass straight through normal matter) as the reaction mass.

[TK421d]

I'm making one of my radial engines a pure electric, by adding an alternator instead of a pure generator. i just want it to run, not refill some other part, so it only creates the resource while the engine is operational.