The ISS has the four (pair) sets of solar arrays that can generate 84 to 120 kilowatts of electricity. Each of the eight solar arrays is 112 feet long by 39 feet wide and weights 2400 pounds. There were space missions involving astronauts working in space to install and deploy the ISS solar panels.
Alliant Technical Systems, ATK, was selected in 2012 by NASA's Space Technology Program under a Game Changing Technology competition for development of a promising lightweight and compact solar array structure. The MegaFlex™ engineering development unit, EDU, was tested at NASA GRC Plumbrook facility this year. See below for the ATK deployment of the demonstration unit.
Use of high-power solar arrays, at power levels ranging from ~500 KW to several megawatts, has been proposed for a solar-electric propulsion (SEP) demonstration mission, using a photovoltaic array to provide energy to a high-power xenon-fueled engine. One of the proposed applications of the high-power SEP technology is a mission to rendezvous with an asteroid and move it into lunar orbit for human exploration (the Asteroid Retrieval mission). NASA is also exploring options for future power systems for extreme environments, including near-sun environments, solar electric propulsion, and operation on the Venus surface
The unit employs an innovative spar hinge to reduce stowed volume. Deployment is achieved in three stages: release from the spacecraft, unfolding the hinge, and rotating the wing. A single lanyard and motor operates the last two stages. The EDU is 10m in diameter and able to provide ~20kW BOL with TJ cells.
Similarly, Deployable Space System, DSS, developed a roll-out array, ROSA, EDU that employs an innovative stored strain energy deployment to reduce the number of mechanisms and parts. The elastic structure maintains stiffness throughout deployment for partially deployed power generation. The rectangular design can be configured in many ways by either lengthening the booms, adjusting the length and width, or attaching several winglets onto a deployable
backbone. Lengthening and/or shortening the booms provides power scaling without changing any of the subsystems or stowed configuration. See below for a fully deployed ROSA array.
* four 150 kilowatt wings would be 600 kilowatts in power. The new wings are easy to deploy and do not involve astronauts.
* eight 150 kilowatt wings would be 1.2 megawatts
Ion drives are ten to twenty times more fuel efficient than chemical engines.
Spider fab robotic assembly in orbit can get to 1 square kilometer or larger structures
Getting to 1 square kilometer would mean going from 1600 square meters and 150 kilowatts to 1 million square meters and 90 megawatts.
Here is the Spiderfab update.
Improving and testing reliability and a lot of engineering would be needed to get to 100 kilometer structures.
Making 6U cubesat trusselator to put out 50 meter trusses and make truss of trusses from several
They are using Baxter robot to work with trusselators.