[klean92]

Slightly off-topic, but i find impressive that with the same 2,500 calories needed to power daily my moderately used smartphone, my body can walk, go up the stairs, lift heavy objects, do math, laugh and think.

Way to go to match the efficiency of the human body.

[snaily]

I can't make sense of this statement in the article - it seems to be off by two orders of magnitude.

A typical smartphone battery (Xiaomi Mi4i) is specified at 3.12Ah @ 4.4V. Multiplying, we get an energy content of about 50 kilojoules, which is about 1/200th of the a typical daily human energy requirement (10MJ).

[anon4]

As snaily said above, your smartphone really doesn't need 2500kcal/day. I think what they were trying to say is that, given 100% perfect energy transfer, you'll be able to power your phone from your daily calories without missing much. As in, "this is so much, you can power a phone without realising something's missing".

[_Adam]

Dietary calories are actually kilocalories. 2500 kcal is approximately 3kWh..enough to run a thousand phones for an hour.

What's impressive isn't the efficiency of the body's use of energy (electric motors are already pretty good) , but rather how efficiently it extracts and stores it.

If smartphones had our stomachs, we wouldn't need to charge them..just let throw a hamburger in there once a month.