Cut Energy Use

Entry by: Alex Fleet

17th October 2022
At last the message is getting through. People are starting to realise how important it is to save power. But how effective are their actions?

I’ve just popped upstairs. It is dark, so the light has come on automatically and will switch off when I am not on the stairs. This is not a mains light, it is a small battery-operated light which cost £5 in a DIY shop I visited in passing. I use used AA batteries which do not have enough power for the old camera I sometimes use, but which have enough power left over for a torch. Or sometimes I use rechargeable batteries. This is instead of paying an electrician to drive out specially and use power to fit a more sophisticated light which has no doubt cost more to manufacture than my little £5 light. However, how long will my little £5 lamp last? Probably not so long as the proper light, so maybe I will spend more in £5 lamps in the long run than fitting a proper one. Does it cost more to the environment manufacturing several batteries than making a proper fitting and using a bit of electricity? Maybe electrical items need to indicate just how much energy was used in creating them, same way as food now contains comprehensive information on its ingredients.

At last the government is encouraging us and the industries involved to explore alternative energy sources. But why didn’t they do that back in the 1970s, or even earlier, when the warnings first started of what would happen if we continued with our pays of creating power and moving transport. Are they doing the right thing now? A decade ago they encouraged us to buy diesel cars, but now frown upon them. A decade ago they encouraged drivers to scrap perfectly good cars, some of them classic, in order to buy new, less polluting cars. But how much more pollution was caused in dragging the raw materials out of the ground, forging and moulding and assembling them to create new cars, compared to saving probably a smaller amount of pollution caused by keeping the old cars running? They are encouraging us to buy new, electric, cars, but the materials to produce them are scarce and cause their own pollution in their creation.

But things may be looking up. “Alternative” power sources such as wind and solar energy have been sneered at by many quarters and they certainly need improvement – had we started serious development years ago the technology would have been a lot more advanced by now. It is acknowledged that their main disadvantage is their unreliability – it is not always sunny or windy. And sometimes they produce so much electricity the energy they produce goes to waste.

The answer is to find a way of storing this excess energy for use when the energy source reduces. In some geographic areas this can be achieved with hydro-electricity, where water flowing downhill from one lake to another generates power, then when there is excess power – at night for example when the demands on the grid are minimal - that can be used to pump the water back to the higher lake. The lakes basically act like a rechargeable battery.
But hydro-electricity is not possible everywhere, so alternative “rechargeable battery” systems are needed. And here it gets exciting.

Although exotic materials are commonly used at the moment for battery systems, there are other far more common materials that can be used. Iron-air batteries are being developed. Yes – that is iron, not ion as in lithium-ion. Iron, clearly, is far more easily available than the current exotic materials: used in a similar way to conventional batteries, passing an electric current creates or disperses rust on the iron, causing an electro-chemical reaction. Too heavy for use in transport, it could however be useful for stationery applications, at source in the vicinity of solar or wind farms.

Another contender for battery applications could be sodium. Sodium (that is, common salt) is very similar to lithium: they are immediate neighbours on the periodic table and they can be handled with very similar technology and behave in similar ways. Sodium is less effective than lithium but in many ways would be far more suitable, not only because it is so prolific. The mines where it is obtained can themselves also be used for other purposes, such as storing other materials which could be used for storing potential energy.

When an excess of electricity from wind or solar can be used to create “green” hydrogen, for example, that can be stored in the salt caverns. The hydrogen itself is versatile enough to be used not only to create electricity for the grid when required but also to power vehicles – that is already in progress. Of the alternatives available at the moment that looks the most viable.

There are exciting times ahead and there is a race between the various technologies. Which one will win? The information I have seen is at a basic level – videos on Youtube – so maybe I too am making incorrect assumptions – like the government has done at times. It is an interesting discussion. Judge for yourself, as a start checking out the links to the videos below.

However: the best action is: to Cut Energy Use.


Iron-air batteries

Sodium-ion batteries

Green hydrogen