Hacker News Reader

Comment by HPsquared | Hacker News Reader

Somewhat different, but this reminds me of an approach that uses temperature gradients in the ocean to power a heat engine.

https://en.wikipedia.org/wiki/Ocean_thermal_energy_conversio...

View on HN

OTECs are amazing, and step 1 of "The Millennial Project: Colonizing the galaxy in eight easy steps"[0]

[0]: https://en.wikipedia.org/wiki/The_Millennial_Project

There's a shore-based research OTEC in Hawaii, but the best is a floating, closed-loop OTEC in the ocean.

Interesting link. I would think step 7 would come before step 6 though. I thought about this for a few minutes and can't come with a reason otherwise.

The timelines are increasing powers of 2. It’ll take much longer to colonize all asteroids than to settle Mars.

wiki article states "Up to 10,000 TWh/yr of power could be generated from OTEC without affecting the ocean's thermal structure". which converts to about 500GW which... isn't that much

10 000 TWh/yr is one third of the current total electric energy generation of the whole planet, is not a small amount.

Source, page 39 of the full report:

https://www.iea.org/reports/global-energy-review-2025/electr...

This can't be correct.

10,000 TWh/y = 1e+7 GWh/y, divide it by 365.25 days/y to produce daily output of 27,379 GWh/day, then by 24 h/day to get pure power of 1,141 GW. It's still more than a terawatt, three orders of magnitude larger than the largest nuclear reactors.

oops. yes. still not that much though. i mean it's a lot but it's "one more large industrialized country" a lot not "kardashev 2" a lot

Those goalposts of yours are on a FTL ship...

Kardashev 2 has a Dyson sphere. Of course anything on a single planet can never have that much.

Reply on news.ycombinator.com