Elon Musk’s five insights into solar energy

[NickB79]

3. Nothing is "inherently exponential" for long periods of time

Whether we're speaking of solar panels or bacteria in a Petri dish, exponential growth rates can't be sustained for long periods of time.

I note that SciAm's blog did investigate the idea of Moore's Law applying to solar:

So is there such a phenomenon? The National Renewable Energy Laboratory of the U.S. Department of Energy has watched solar photovoltaic price trends since 1980. They’ve seen the price per Watt of solar modules (not counting installation) drop from $22 dollars in 1980 down to under $3 today.

See what they did there? Solar is following Moore's Law of exponential growth, so long as you ignore installation costs that would otherwise fuck up the exponential growth claim. The solar cells themselves are indeed holding true by and large, but installation costs aren't keeping up as things like automation improvements and labor costs refuse to move as much.

That doesn't mean that the growth in renewables, including solar, hasn't been anything short of stellar in recent years, or to argue against their continued deployment at the fastest rate possible. Even though I think calling solar's projected growth exponential is a distortion, we should do all we can to ensure it grows as close as possible to exponential to salvage what we can of modern civilization.

A fellow DU'er once wisely cautioned me against extrapolating short-term rates of change over long periods of time, because eventually you'll realize your young child will be 15 ft tall by the time they reach puberty