• "Given that Scotland can produce 400% of what it requires in cheap green energy, is it not a key economic argument for independence?"

The answer is, of course, that it is.

I have a habit that does, I suspect, annoy my wife. What I do when visiting a place is ask what makes its economy tick. I try to do it silently these days, but the question never goes away.

It is one of things that really interests me about travelling. And when I say travelling, I mean even relatively short distances, because I ask this question of anywhere from a village, to a town, to a city or country. It’s as valid however big or small the location. To understand a place you have to work out what really does make it tick.

READ MORE: As nations benefit from Scottish renewables we lose out

Vitally, that question means you have to look beyond all those things that most places have in common. They are not hard to spot. The reality is that the vast majority of the economy of any place, again whether large or small, is dedicated to servicing the needs of the people in that community. Retailing, education, healthcare, care, the repair and servicing industries, and so much more are all about doing these things. They are really important. They make massive differences to lives. We most definitely notice them when they’re gone. But, for all that, they are not what makes a particular place tick.

The tick comes from what is different about a place. Where I live right now it is tourism.  Where I lived before moving here it was agriculture. And before that I lived in a suburb. Providing dormitory services was what made that place tick.

Go to a city, rather than the smaller communities I prefer, and it is harder to work out where the tick is. For example, is Edinburgh really only about festivals and tourism? Clearly it is not. But equally, we can be sure it is not now so much about financial services in the way it once was, and might need to be again if Scotland is independent.

READ MORE: Rishi Sunak told to act for pumped-storage hydro renewables

It should follow from the logic I have just explored that saying what makes a country tick should be harder still. I am not, however, sure that is true. At the risk of offering some appalling generalities, what makes a country tick is very often readily apparent.

Napoleon thought England was a nation of shopkeepers.

These days he would think it all about financial services and the post-colonial desire of the City of London to replace its former direct power on the world with the indirect power that the control of money brings.

Germany is about manufacturing. Someone has to do it. They do.

France? That’s harder, but isn’t its essence about making the finer things in life that support luxury? Is it any wonder there are so many social tensions as a consequence?

And, the US? It is built on the naked power of the dollar and the military that it supports, which is utterly disproportionate in size.

I accept that all of these are caricatures. But, like all rules-of-thumb, what they suggest can be useful. They hint at why these countries place priority on some issues over others. They do so because that is where they think that the source of their wealth lies. Quite literally, they know what makes them tick.

And so to renewable energy, and Scotland. My suggestion is that Grant Smith had worked out what will make an independent Scotland tick. At one time everyone thought that oil would make Scotland tick. No one does now. The world has moved on.

So too can Scotland. The world need renewable energy.

There are few countries in the world with better natural resources capable of delivering renewable energy way in excess of its needs than Scotland. It is the export of that excess energy that will make Scotland tick. And if it can export that energy in manufactured form by turning that capacity to generate power into the energy intensive products that other countries will not be able to afford to make, then the value-added that Scotland might make could be even bigger.

Any plan for Scotland's future that does not put renewable energy at its heart will be missing the point of what will make Scotland tick in the future.

The choice for Scotland is does it want the advantage that this brings or is it willing to let the politicians and bankers in London exploit it? It is as simple as that.