The other day I was in a supermarket and was shocked to find a portable CD player on sale for £6 / $12 and not really any better than the one I bought 7 years ago for £150 / $300. We all know the first part of the story as to why this happened; scaled-up low cost Chinese manufacturing. The second reason for these fast-falling costs, the hardware refresh rate, needs further exploration. The hardware refresh rate is all about how often a given product is replaced. I'm only a very occasional music listener, but I've had two mp3 players since then, so I have in the course of 7 years, refreshed the hardware twice. That's typical with consumer goods, the hardware refresh rate tends to be far quicker than the lifetime of the product itself. Perhaps the ultimate example is the mobile telephone - probably about once a year or certainly every two.

So what does this have to do with alternative energy technologies?

I think the rollout and development of alternative energy technologies needs to be thought of not just in terms of increased production yielding lower costs, but in the rate of hardware refresh rates. For background, read this usefully sceptical piece about plans to switch Israel to all electric road transport in 10 years.

So here are the hardware refresh rates and an important reason why they're won't be a Moore's law for solar, wind, fuel cells or anything else in the near future;

Conventional road vehicle - 15 years
Conventional power plant (coal, gas, nuclear) - 40 years

Solar PV - 30 years
Wind turbine - 15 years
Fuel cell - maybe 15 years?

The one hardware refresh rate bright spot I would suggest is energy storage because conventional lithium ion batteries have a limited number of charge/recharge cycles - about 500 before they are finished. That has led to plenty of research which is quick to market in extending battery life.