On my drive to the post office on Saturday I noticed that about fifteen houses had sprouted solar panels since my last trip three days before. It got me thinking!
My first reaction was that if all these houses were going to start to provide their own electricity, and sell the surplus to the grid, then would there really be an energy crisis in the future? Thinking like the average 'man in the street' my conclusion was 'no, there won't be'. I even, briefly, thought that (electric) cars may survive!!
But the bubble has since then popped. Whilst we can still provide solar panels for all the houses that need them at the moment, how long will this last? One big problem for solar panels is that they require a small amount of what is known as a 'rare earth' metal - as the name suggests these are not easy to find. Most rare earths are found in China, and China is holding back a large percentage of these for their own use, which is fair enough.
So this suggests that the price of solar panels will inexorably rise, and supply may tighten up. The next thing that sprang to mind is that whilst the solar panels going up now are new and bright and shiny, how long before they will need to be replaced? They are exposed and nobody seriously expects the climate to improve over the coming decades. There will come a point when the cost of rare earth components plus replacement makes their supply very difficult indeed. This is of course where scalability comes in. To encourage take up of solar panels the government was making installation free plus there was a guaranteed income for 25 years. This is already being scaled back.
This problem of resources and scalability comes into play wherever a replacement for fossil fuels is introduced. Biofuel died before it even began, because it straight away began to put pressure on food prices. Hydrogen will almost certainly face the same fate. Windmills need rare earth metals as well as a lot of conventional metal, plus maintenance. No doubt the same applies to hydroelectric, tide and wave power. There are always costs, and things that are trumpeted as panaceas often have a very short shelf life.
It brings us back to the initial problem of how we replace fossil fuels, and also to the enormous superiority of rail over road. It will be energy-efficient designs and modes that triumph in the long term, and the idea that we can continue to live energy-wasteful lives IF THAT ENERGY IS GENERATED SUSTAINABLY will soon be shown to be a greenwash and cop out.
So if seeing all these solar panels and windmills going up gives you a warm feeling remember that they will have huge problems once they take off on a large scale. We'll still be here waiting to lay our rails ...