1000 X 15 ton skylon payloads
Build the first 5 gigawatt space based solar power (32500 tons) at 2000 kilometers above the space junk. Afterwards use the first SPS to help boost the other launch stacks to construction at 12,000 kilometers in the low radiation area.
The SPS would be stationed at 18,000 kilometers. Making SPS propulsive allows for half the distance of GEO. This would reduce the size of rectannas.
To replace oil in a decade would require 400 5 gigawatt