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157 points Helmut10001 | 1 comments | | HN request time: 0s | source
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kacesensitive ◴[] No.43593217[source]
Earth gets over 170,000 terawatts of solar energy every day—10,000 times more than humanity uses. Losing just a fraction of our cloud cover means a massive, invisible throttle is coming off the climate system. If this trend holds, we’re not just warming—we’re stepping on the gas.
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dbacar ◴[] No.43593273[source]
terawatt is not an energy unit.
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spacedcowboy ◴[] No.43593349[source]
R̶e̶a̶d̶ ̶t̶h̶e̶ ̶c̶o̶n̶t̶e̶x̶t̶…̶

- A̶ ̶w̶a̶t̶t̶ ̶i̶s̶ ̶d̶e̶f̶i̶n̶e̶d̶ ̶a̶s̶ ̶1̶ ̶j̶o̶u̶l̶e̶ ̶p̶e̶r̶ ̶s̶e̶c̶o̶n̶d̶

̶ A̶ ̶w̶a̶t̶t̶ ̶f̶o̶r̶ ̶1̶ ̶s̶e̶c̶o̶n̶d̶ ̶t̶h̶e̶r̶e̶f̶o̶r̶e̶ ̶e̶q̶u̶a̶l̶s̶ ̶1̶ ̶j̶o̶u̶l̶e̶,̶ ̶a̶ ̶m̶e̶a̶s̶u̶r̶e̶ ̶o̶f̶ ̶e̶n̶e̶r̶g̶y̶

- A̶ ̶T̶e̶r̶a̶w̶a̶t̶t̶ ̶f̶o̶r̶ ̶a̶ ̶d̶a̶y̶ ̶i̶s̶ ̶t̶h̶e̶r̶e̶f̶o̶r̶e̶ ̶a̶l̶s̶o̶ ̶a̶ ̶m̶e̶a̶s̶u̶r̶e̶ ̶o̶f̶ ̶e̶n̶e̶r̶g̶y̶.̶

[edit: The earth receives 14.9 ZettaWatts of solar power per day, and 173 Petawatts per second, I was reading it as 173 PW over a day, in which case the above works fine. Mea culpa]

See: https://gosolarquotes.com.au/amount-of-solar-energy-hitting-...

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CorrectHorseBat ◴[] No.43593557[source]
No they don't, you need to divide, not multiply just like you would with every other unit. 1l of rain every day is 1l/day, not 1l * day . Which means Watt per day is J/s^2
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1. jijijijij ◴[] No.43593805[source]
If you want to be nitpicky about semantics, I think the only valid interpretation then is to take OP by their words and assume they meant energy transfer for 24h, since they did not write "per day" as you suggest:

"Earth gets over 170,000 terawatts of solar energy every day"

= 170 PW × 1d

= 170 × P(J/s) × 86.4 × ks

= 170 × 10¹⁵ × (J/s) × 86.4 × 10³ × s

= 14.6 × 10²¹ × J

= 14.6 ZJ

However, I also think "of solar energy" could be read as specifying the type of energy for the "rate of energy transfer", which is already implied in 'watt'. And since it's related to energy usage (rate), there really is no need to leave the "rate of energy transfer" interpretation at all and get hung up on "energy vs. power":

"Earth receives 170 petawatts as solar energy - 10,000 times the energy humanity uses, at any moment.

Edit: And let's be real, we all only feel very smart here because we just watched the latest Technology Connections video https://www.youtube-nocookie.com/embed/OOK5xkFijPc :D