These numbers are not accurate.
It is not stable to restrict people to poverty.
Everyone needs to have high basic standard of living.
The actual energy requirements to bring every person on the planet to a standard of living that we would consider a high basic standard of living, and leave 50% of the land in a natural state, would use 30% of the remaining energy available.
We could bring a high modern standard of living to about 20 Billion people without impinging on the ocean.
If we start to seriously modify the ocean, then we could support about 70 billion people on this planet – at a standard of living any of us would consider reasonable.
Beaming in more energy isn’t necessarily a great idea – maintaining heat balance is hard enough already (think global warming). Doing heavy engineering in space by remote might be a good idea. Building orbital habitats is almost certainly a great idea. Coal would be a great source of carbon and hydrogen, to make water and life.
Ted Howard NZ's Blog 