China has announced plans to build a giant solar power space station, which will be lifted into orbit piece by piece using the nation's brand-new heavy lift rockets.
  • humanspiral@lemmy.ca
    5·
    2 days ago

    headline not claimed. 1 km2 as a continuous flat surface that can be pointed at sun is 250mw from commercial cells. Outside of our atmsophere, irradiance boost is only 33%. so 340mw. Geosynchronous over China will only gain up to 3 hours per day of sun. That can be a 75% boost in average daily power.

    except microwave energy transmission… While a 50% efficient transmission is possible (effectively 250mw earth equivalent delivered), it needs a 100 square km receiver array. Even at 150mw per square km earth solar, is enough space for 15gw of solar.

    So, it only makes sense at much larger scale, and only makes sense if denser energy costs as astronomically high as such a project. Beaming energy to other points in space, or even remotely powering a spacecraft are applications.

  • Dropper-Post@lemm.ee
    13·
    2 days ago

    Lately i heard so many amazing things that china will do. I almost now want to live in china and not usa anymore. They got me convinced.

    • ☆ Yσɠƚԋσʂ ☆@lemmy.mlOP
      13·
      2 days ago

      I’ve been slowly learning Putonghua for the past two years here. At this point, I just can’t see how anything gets better in the west in the near term, meanwhile life in China is improving by leaps and bounds each and every year.

  • balsoft@lemmy.ml
    8·
    2 days ago

    The article is very light on details, but the numbers don’t seem to check out at all. Back-of-the napkin math (assuming a square 1km × 1km solar array and total sun luminosity of 3.83e26 W):

    1 km ^ 2 * (3.83e26 W) / (4 * π * (1 AU) ^ 2) * 1 year to TWh ≈ 11.94 TW·h

    This is a “measly” 12 TWh of TOTAL energy delivered to the array over a year - not accounting for solar panel efficiency losses (20-24%) or the elephant in the room of transmitting this energy back to earth. For context, China alone consumed around 39 PWh (39000 TWh) of energy from fossil fuels just over the course of one year, 2023. The entire world consumed 55 PWh (55000 TWh) of oil energy in 2023 alone. It’s not even comparable to the annual consumption of oil. If we consider the aforementioned factors, assuming 24% solar panel efficiency and an extremely generous 50% power transmission efficiency, we get:

    1 km ^ 2 * (3.83e26 W) / (4 * π * (1 AU) ^ 2) * 24% * 50% ≈ 163.43 MW

    Which is literally nothing on a national scale - it’s less than a percent of the Three Gorges Dam output.

  • hotspur@lemmy.ml
    6·
    2 days ago

    I was hoping the article would explain how they planned to transmit the energy in a useful way. It says beaming back my microwave, but I have no idea how that works or if it has a good scale potential. Guessing they’re targeted at some surface that vibrates or heats up and that geberates the power on the terrestrial side of the equation?