> This graph is from Tim's website and illustrates the relationship λ (lambda) between the world't total accumulated wealth (C, the integral) and our ever-accelerating energy consumption rate (a, measured in 10^21 joules per year)

It's an odd choice to use global accumulated wealth rather than the global equivalent of GDP (GWP). What are the error bars on the calculation for how much the entire planet is worth in dollars?

For reference, GWP growth rate has been between 3% - 6% in the period considered by that paper. If the net world wealth growth rate was 1.82% during that period, it would suggest that depreciation effects are significant in determining that figure.

"It's an odd choice to use global accumulated wealth rather than the global equivalent of GDP (GWP)"

No, it isn't. If you own a house that has already been build it does not influence GDP. Yet you need to finance repairs and maintenance (and therefore Energy).

The problem with most infrastructure is actually not to build it but to sustain it.

That's an interesting point. To give a sense of scale, at least in the context of the US market:

"According to US News and Freddie Mac, homebuyers should actually budget up to 4% of the property’s value in annual maintenance costs." [0]

"house price rises have averaged more than 5 percent over the last few years." [1]

[0] https://www.upnest.com/1/post/what-is-the-annual-cost-of-mai...

[1] https://www.cnbc.com/2018/06/06/us-house-prices-are-going-to...