I was delighted to see the letter on fracking from my friend and contemporary Alan Mears (Oxford Today, Trinity 2015). I agree, and offer an engineer’s point of view.

It’s not love, or even money, that make the world go round: it’s inertia. Our little island is ideal for harnessing the energy of tides and there are many ingenious ways of doing this, both small and local, The Earth’s inertia is one of the greatest gifts we’ve got and we should make more use of it. And don’t worry about its inevitable unrenewable energy cost: our descendants will have died out long before the resulting lengthening of their days or increase in their weight become perceptible.