A Type I unit of power, the Sol

[selfAdjoint]

It's fun to think about the far-out Type II and III civilizations, but how close are we now to Type I?

M. Kaku says the output of our star is about "a billion trillion trillion ergs per second". That is, if I have done the arithmetic correctly, 10^33 ergs/sec or, dividing by 10^7, 10^26 watts. Note that this is power, rate of producing or consuming energy that we are talking about. I propose to name this amount of power the Sol. Numbering your power flux in Sols would be a practice of a Type I civilization.

Currently we measure the power consumption on earth in quads, quadrillions of BTUs per year. That's 10^15 BTU/yr = 3.169 X 10^10 watts. In 2000 the earth used energy at the rate of 300 quads per year, or about 10^13 watts. Notice that this power, 10^13 watts as numerically the square root of 1 Sol = 10^26 watts. This says that on a harmonic progression scale, we are half way from 10^0 watts (idly scratching) to the mark of Type I, the Sol.

Go humans, go!

[chroot]

An interesting fact that I tell my students is that the Sun produces more energy every second than mankind will use, at the current rate of consumption, in three million years.

- Warren

[Nereid]

With the exception of nuclear and geothermal sources, we live by eating the Sun, past and present. IIRC, we are eating the past Sun at a rate several hundred times faster than it was produced. Looking purely at power consumption - SelfAdjoint's numbers - and with a small envelope, our present power consumption is ~0.1% of the Sun's present power output, as received on Earth (my envelope is quite small; in trying to square SelfAdjoint's numbers with chroot's, I find a factor of ~10 has crept in somewhere).

Of course we eat more of the Sun than just raw power to run our cars, light our homes, and surf the internet; we also eat and keep warm. Does anyone have a handle on how much of the Sun-on-Earth, in total, we consume?

[chroot]

I thought worldwide power consumption was around 4 terawatts. selfAdjoint believes it's closer to 40 terawatts, but, frankly, I don't know. I'm sure someone has done a detailed study and listed a specific figure somewhere. My guess is the number of sig figs in selfAdjoint's 3.169 X 10^10 watts is due to some relatively precise authoritative measurement. So, let's be generous and say mankind uses 40 TW.

- Warren

[selfAdjoint]

World power usage is in hundreds of quads, here is a Physics Today analysis. (http://www.aip.org/pt/vol-55/iss-4/p38.html)