Electric aircraft are a reality - what about electric spacecraft?
#1
So here's a recent CNBC news story about electric aircraft.

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Although we're still dependent upon chemical reaction propulsion for spacecraft, science has already proposed a number of alternative means of propulsion from laser-powered light sails to ion-generated engines.

Something will have to convert mass to energy and something will have to create a reaction that moves a spacecraft away from its launch point. But what if we can develop battery-powered spacecraft that are able to travel along special gravitational conduits. Think about leveraging the slingshot effect to propel craft around the Solar System. They just need enough energy to get into position to dive toward a gravitational mass (like a planet).

If engineers believe they can build batteries capable of moving a 737-sized aircraft through the Earth's atmosphere in the next 10 years, then I think electric-powered spacecraft may not be that far beyond 10 years.

We already have solar-powered satellites that use the sun to power their non-propulsion systems. What will it take to design and build craft capable of harvesting energy from the sun and using that to power propulsion systems?
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#2
Ion thrusters and plasma thrusters are electric low-thrust engines in use for mainly deep-space probes. The thrust developed by the current designs in use are low, but thrust can be sustained a relatively long time and could be powered by solar energy, stored electricity, or nuclear isotope or reactor generators. Ion thrusters use electrical charge fields and plasma thrusters use magnetic fields to fling ionized particles backwards, driving the spacecraft forward with the reaction. Plasma engines are electricity hogs; one typical model consumes 20 kilowatts to generate 5 newtons (1.124 lb) of thrust. At one AU (average radius of Earth orbit around the Sun) this would require almost 15 square meters of solar power capture to supply, plus inefficiency, and more as the craft gets farther from the Sun per the inverse square proportionality principle.

These systems, esp. ionic, do not generate enough thrust to overcome gravity or air resistance, and have other drawbacks such as a tendency to erode their own structures over time at high output, therefore I can't see they will be practical for propelling aircraft or launching spacecraft from a planet or large moon for the foreseeable.
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#3
Well, I'm sure you're right about all that, but only a few years ago the idea of powering an airplane with batteries was seen as impossible (given the technology of the time).

The question is: how far can we take these technologies for collecting and storing energy from the sun (or other sources)?

I don't see these kinds of propulsion systems being used to launch heavy loads into orbit or on journeys to the outer regions of the Solar System. But could we launch electric-powered craft from orbit (assembled in orbit) and send them into other parts of the Solar System (presumably within the boundaries of the Martian or asteroid belt orbits)?

Using today's technology, we can't do more than you say. But where will the technology go in 10-25 years? That's what I'm getting at?

And if a science fiction writer wants to project farther into the future - what might be conceivable 100 years from now?
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