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If they're going to have something called a NERD NOTE, they should at least get their units right:

"The entire planet’s electrical consumption is right around 5 terawatt-hours."

5TWh per what? Per second? Per hour (then why not 5TW?)? Per year? Cumulative over all of human history?




Its roughly 5 TWh per 2h (to spare you the algebra, thats 2.5 TW power generation)

Source: https://en.wikipedia.org/wiki/Electrical_power_generation


Watt is joule/second.

Write it out and algebraically cancel the units and you'l understand that you don't understand, and then maybe you will.

As a rule, in future, try to understand before mocking, its a better way to live, take it from me...


I think you've misunderstood the point. Terawatt-hours is ambiguous, without specifying a time period.

In particular, Terawatt-hours can be converted to Joules. To say that humanity's energy usage is X Joules is meaningless without specifying the time period that that energy is used over. For example, it means very different things to say that humanity uses 5 TWh per day than to say that humanity uses 5 TWh per year (versus 5 TWh since the dawn of recorded history!).


The context is deathprint” (casualties per terawatt-hour) or deaths/joule, time cancels out. If you read the NERD Note alone your right of course.


That's not the context that everyone else is referring to. They are referring to this:

"[NERD NOTE: A terawatt is a trillion watts. The entire planet’s electrical consumption is right around 5 terawatt-hours. One TWh (terawatt-hour) is a constant flow of a trillion watts of electricity for a period of one hour.]"

The argument others are making (which I think is correct) is that it is meaningless to say "The entire planet’s electrical consumption is right around 5 terawatt-hours" without specifying a time frame over which that consumption occurs.


A terawatt-hour is 3600 terajoules (a measure of energy, not power). So you've got your units wrong, unfortunately.


You might say, for example, that "in 2008, the world total of electricity production was 20,279 terawatt-hours (TWh)." You need the time period however for it to make sense. Referring to a continuous generation capacity would be measured simply in terrawatts. As in "this number corresponds to an average rate of around 2.3 terawatts continuously during the year."

The original article has an error as pointed out by the parent. Insert ironic mocking statement here.


There is not time period in context of deaths/joule. There is only a error if the note is taken out of context. On its own its ambiguous sure.




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