How much food do you need to eat if you want to shoot lasers out of your eyes continuously?

This post was inspired by Cyclops from X-Men who shoots red lasers out of his eyes. To stop him frying everything in sight, he wears some nifty glasses to block the light which he takes off to zap the bad guys.

Just how much energy would his eyelaser consume?

File:Industrial 4kW laser with flying optics system.jpg

Wikipedia reckons an industrial cutting laser uses 100-3000W on average.  To make things easier for Cyclops lets assume he has a 100W laser in his eye (given his name I guess he only has one eye?).  This means his laser is consuming 100 joules of energy a second.

There are 24×60×60 = 86400 seconds in a day so Cyclops must be burning through an extra 8,640 kilojoules each day compared to a normal bloke.  The body turns food into physical power with 18-26% efficiency.  We don’t know how good Cyclops is at turning food into laser power but lets assume it’s similar to this and his body has an efficiency of 25%.  This means he has to eat an extra 34,500 kilojoules every day compared to the average man.

A Calorie is just over 4 kilojoules so this equates to around 8,300 Calories.  Recommended daily energy intake for a man is 2500 Calories so Cyclops must be eating at least four and a quarter times as much as I do.  This is certainly possible if he is eating lots of energy rich foods (think lots of chocolate).

At any rate we now know who eats all the pies in the Xavier Mansion.