Someone once told me that the reason arctic animals are often very large is because they have a lower surface area to volume ratio that smaller animals, and therefore dissipate less heat. Has anyone else heard this?
The way this came up was that I am having a debate with a friend about whether it is more energy-efficient to install a switch on a water heater and turn it on only once every few days. He thinks that this is the most efficient use of a water heater. I think that a larger volume heater uses more energy to heat up water from cold that it dissipates in heat over a couple days, especially if it is wrapped in blanket insulation.
I'm curious if anyone has insight into this.
Yup, that's why I believe hair colour of many Northern European children changes from very fair when young, gradually darkening through to adult.
The water heater would give off MORE heat if it is kept hot. heat that must be replaced.
Don't confuse power and energy.
What if it was off for a year?
Would you agree then that it would be better to turn it off?
And you are off about the artic animals being large.
they are roundish.
A sphere has the lowest surface area to volume.
It doesn't matter what size.
Don't confuse power and energy.
What if it was off for a year?
Would you agree then that it would be better to turn it off?
And you are off about the artic animals being large.
they are roundish.
A sphere has the lowest surface area to volume.
It doesn't matter what size.
QUOTE (buttershug+Oct 25 2009, 03:31 AM)
The water heater would give off MORE heat if it is kept hot. heat that must be replaced.
Don't confuse power and energy.
What if it was off for a year?
Would you agree then that it would be better to turn it off?
And you are off about the artic animals being large.
they are roundish.
A sphere has the lowest surface area to volume.
It doesn't matter what size.
It would give off more heat if kept hot, but would it use more power to stay hot or to heat its contents from cold to hot every 2-3 days? Assume a large tank where only @1/4 of the water was used every day or two.
If it was off for a year it would definitely be better to turn it off.
So you think that a tall cylindrical water heater with the same diameter as a short water heater with the same shape would actually have a lower surface area to volume ratio and lose heat slower than the tall one, because it's more "roundish?"
I guess then the optimal energy-efficiency strategy would be to get a small water heater and turn it off before use and only turn it on again long enough to heat the water before using it again.
Don't confuse power and energy.
What if it was off for a year?
Would you agree then that it would be better to turn it off?
And you are off about the artic animals being large.
they are roundish.
A sphere has the lowest surface area to volume.
It doesn't matter what size.
It would give off more heat if kept hot, but would it use more power to stay hot or to heat its contents from cold to hot every 2-3 days? Assume a large tank where only @1/4 of the water was used every day or two.
If it was off for a year it would definitely be better to turn it off.
So you think that a tall cylindrical water heater with the same diameter as a short water heater with the same shape would actually have a lower surface area to volume ratio and lose heat slower than the tall one, because it's more "roundish?"
I guess then the optimal energy-efficiency strategy would be to get a small water heater and turn it off before use and only turn it on again long enough to heat the water before using it again.
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