I've heard a few times that the Sun's energy output per unit volume is less than that of a human, with the Sun's much higher power output being a result of its much greater size.
In a blog post, Phil Plait runs through the numbers and concludes that humans put out 60,000 times more energy per unit volume than the Sun. However, he also makes the counterargument that one shouldn't assume the energy generation density is uniform inside the Sun, since most of it takes place in the core.
I would like to know how heat generation is distributed inside the Sun. Is it more or less uniform inside the core? Is there any part of the Sun that generates substantially more energy per unit volume than a human?
Phil Plait seems to say that there is, but I think he makes an error in his reasoning: he seems to imply that because the temperature of the inside of the Sun is millions of Kelvin, it must be generating millions of times as much heat. But of course, the temperature isn't the same as the rate of heat generation. If the core of the Sun were thermally insulated, it could stay at millions of Kelvin without generating any heat at all. (Of course I know this isn't really the case.) So I would like to know the figure for the amount of heat generated per unit volume in each part of the Sun.
