The National:

Good evening! This week's edition of the In Common newsletter comes from Robin McAlpine, the director of Common Weal. To receive the newsletter direct to your inbox every week click here.

THE National had an interesting article on energy from Lesley Riddoch and response in the letters page from George Rennie.

George accused Lesley of making errors in her article but also made quite a number in his response. It is worth spending a second on why this is such a complicated issue – and why it is really daft to be pessimistic about Scotland's energy future.

The first thing I'd take some issue with is Lesley writing that there hasn't been much work done on post-independence energy. That's not really right; Common Weal has done absolutely loads – our energy team includes people who have very senior electricity grid technical expertise.

That is probably why people don't know about it – it is a highly technical subject and some of our papers are technically dense, so let me give you some simplified explanations of why this isn't simple.

Let's say you're planning a post-independence electricity system – what do you do with "wrong time generation" (the wind blowing overnight when no-one is using it)? George implies that we'd keep doing what we do now and pay the private owners of the wind turbines a generous sum to dump that electricity.

But that assumes we're maintaining the UK energy market and market regulations. That would be really daft because they're a giant, sprawling mess. Ireland does not pay so-called "constraint payments" (paying people to dump electricity). But anyway it is now simply daft to dump any electricity at all because storage technologies have advanced so much.

There are two top options. One is battery storage, the other hydrogen. Sodium ion batteries are an exciting development because they're cheaper and cleaner than lithium batteries, can be made from sea water rather than rare earth mining and get less hot. They won't be used in cars because they are about a third heavier for the same capacity, but that doesn't matter for non-mobile applications.

READ MORE: Line-up confirmed for The National's indyref anniversary event

You can't store weeks of energy, but you could store overnight and provide that electricity at a discount to energy-intensive businesses the next day, or sell it back to the grid to export south – or a host of other things. For long term storage we'll probably use hydrogen, but that can be in the form of a gas or it can be converted into ammonia.

Electrolysis is simple – you run electricity through water and it breaks it down into hydrogen and oxygen. If you combine the hydrogen with nitrogen you get ammonia. That can be used as a fuel or to make fertiliser. If you store it as a gas you want to produce and store it close to existing gas fired turbines because they can run on hydrogen and hydrogen is a nightmare to transport.

Ammonia is not. If you're storing your hydrogen as ammonia you want to do it where there is large supply and low local demand – so you put it in Caithness. All these choices must be made.

The grid should certainly be nationalised (the UK is the only European country with a privatised grid), but what do you want to do with generating companies? You could leave things as they are and allow Scotland's energy to be owned by foreign corporations, like our oil.

(Image: PA)

Or you could legislate such that only Scottish-registered companies that pay tax in Scotland can get generation licenses.

Or, since all renewable energy generation needs to be relicensed at minimum every 20 years, you can just wait and gradually take the licenses back into public ownership. Over 20 years you could nationalise the entire energy generation system without paying any compensation – but you'd have problems with an EU that demands a privatised energy system.

And there are many options for the way you buy electricity for your house. Again, at one end you can maintain the free-market anarchy which is the UK retail energy market, or at the other you could have a single mutual company owned by customers selling electricity to households at cost-plus-reinvestment rates.

The point is that whichever system you want to move towards you need to plan it. In fact you need to plan it now because we're rebuilding the grid as we speak. All the decisions above would shape that grid if Scotland was independent.

READ MORE: Edinburgh Council votes to approve plans for tourist tax

We're not, and energy policy is reserved. We're currently being engineered as an energy supplier for England but we're still being asked to pay way more for Scottish electricity than it costs to generate it because of the UK market. If Scotland split its grid from the UK right now and simply regulated the whole system on the UK basis, you'd see your bills drop by a third. The options for a different regime of infrastructure development, ownership, regulation, energy storage and retail markets are vast.

What Common Weal has argued really strongly is that, while we're not independent, we can still shape our energy system and there is still lots we could do even under the UK regime. But only if we plan it.

That is why we've called for the Scottish Government to establish a Scottish Energy Development Agency (backed by SNP members at conference a few years ago) to devise Scotland's energy future. Unless we know where we're trying to go, the path to get there will never be clear. It is simply wrong to assume that a post-energy system in Scotland would have to be bound by the same rules we have now.

But equally we won't achieve a better vision by wishing it to be true. What until Scotland can adopt the mindset of a nation with aspirations to become independent and we plan accordingly, we really will be stuck with the dysfunctional, anti-Scottish energy system we have.

And if we stumble into independence without properly preparing for it, we will inherit a mess with no roadmap on how to get out of the mess. The time to avoid regret over lack of preparation is always sooner than you think ...