Saltwater causes a sea-change in energy generation
You might not think much could come of sea water, but you’ll be surprised to know it is brimming with potential.
Unlike freshwater, sea water contains such a high concentration of salt that it simply isn’t drinkable unless distilled. What good could it possibly have, you may ask? Just as the seas are teeming with life, sea water is teeming with potential energy, waiting to be tapped into.
As one of the most abundant resources on our planet, sea water could be the oil of the future – we just need to find the right use for it, and harness its power the correct way.
A catalyst for change
As mentioned, sea water is highly concentrated with salt, or sodium chloride. The US-based National Ocean Service estimates that the world’s oceans have a salinity of 35 parts per thousand, suggesting that 3.5 per cent of the weight of seawater is derived from dissolved salt alone.
Our oceans are salty because they collect a large quantity of dissolved mineral ions from rocks on land and under the sea.
In July 2020, the University of Rochester published a paper in the Energy & Environmental Science Journal, suggesting that the US Navy was getting closer to being able to use seawater as a reliable source of fuel for ships. It all comes down to using a catalytic converter to separate the CO2 and hydrogen molecules from saltwater. The gases this produces can then be converted into liquid hydrocarbons, to be burnt as fuel.
If scientists could make this process as efficient as possible, ships would be spared from having to be constantly refuelled at ports or by other ships, provided they had the equipment to generate their own seawater-derived fuel. The current sticking point is the difficulty of converting CO2 into hydrocarbons, as scientists are having to make do with generating carbon monoxide instead.
Worth its weight in salt
In the ancient Roman era, salt was linked to the way soldiers were paid (as evidenced by the word salarium). It remains unclear whether soldiers were either paid in actual salt, or simply paid money to buy this commodity, but the concept became inextricably linked to the phrase “worth one’s salt” and even our own word for earning money, ‘salary.’
Whatever the origins of the concept, salt was clearly such a precious commodity in the ancient world, as it preserved food and was costly to generate large quantities of it. Now, salt is abundant, and we think little about what the salty seas could offer us, other than a refreshing swim on a hot sunny day. But changes are afoot.
Not only is the US Navy looking into the power of catalytic conversion, when it comes to saltwater – car manufacturers are researching innovative ways to harnessing seawater to power the cars of the future.
German car manufacturer Nanoflowcell unveiled designs for a new model, the Quant 48Volt, which it intends to present as the world’s first electric car, powered by sea water. The model uses flow cell technology to give two tanks of water opposing charges, using dissolved metallic salts. A membrane is then used to strip the positively-charged molecules of their electrons, unleashing enough energy to power the car’s engine.
Nanoflowcell calls this type of fuel ‘bio-ION’, which is effectively a form of electrolysed liquid. The benefit of using salty water as fuel is that it is non-toxic and non-flammable, making it more environmentally-friendly, and safer to use than petrol, diesel or other hydrocarbons.
The Quant 48Volt boasts to be a safer type of electric car, by using a lower voltage than conventional EVs charged up at power points. Despite the low voltage, Nanoflocell claims the model can travel for a distance of 621 miles at a time before requiring a refill, and reach 0-60mph in just 2.4 seconds.