No idea how good the source is, however it looks like we have a nice exponential there.
Lets see what the envelope says for an exponent of 2:
Using numbers from parent commentors, log2(6.6 x 10^13) is about 45.9, so we are in our 46th doubling period. A guess on the graph says its 25 years to double.
> The total heat content of the Earth is of the order of 12.6 x 10^24 MJ, and that of the crust the order of 5.4 x 10^21 MJ (Dickson and Fanelli, 2004).
so that's end of crust energy usefulness at the start of the 72nd period and end of Earth energy less than halfway through the 84th period.
So that gives us 500-1000 years of energy from now if we solely use the planets heat. Whether we soley use it or not becomes largely irrelevant due to the exponent, we can stretch it as a major source a few hundred more years or so.
Of course, if in 1000 years we aren't only using this planet we should be good. How many years to the next system again?
No idea how good the source is, however it looks like we have a nice exponential there.
Lets see what the envelope says for an exponent of 2:
Using numbers from parent commentors, log2(6.6 x 10^13) is about 45.9, so we are in our 46th doubling period. A guess on the graph says its 25 years to double.
> The total heat content of the Earth is of the order of 12.6 x 10^24 MJ, and that of the crust the order of 5.4 x 10^21 MJ (Dickson and Fanelli, 2004).
so that's end of crust energy usefulness at the start of the 72nd period and end of Earth energy less than halfway through the 84th period.
So that gives us 500-1000 years of energy from now if we solely use the planets heat. Whether we soley use it or not becomes largely irrelevant due to the exponent, we can stretch it as a major source a few hundred more years or so.
Of course, if in 1000 years we aren't only using this planet we should be good. How many years to the next system again?