The unprecedented situation that we have found ourselves in with the Corona virus outbreak has had some positives. One of these positives has been a reduction in carbon dioxide emissions. This has been due to the effect of the lock down that has been occurring throughout the world. The lockdown has resulted in fewer people traveling which has led to a reduction in transport use and hence the reduction in carbon dioxide emissions.
Environmentalists are hoping that this will kick start a green revolution with people seeking and actively using more environmentally friendly means of transport. One alternative, greener method of transport is to use a car powered by hydrogen, utilizing the fuel cell.
Fuel cells are referred to throughout the course and are covered in the Energy option (option C). They work through a redox reaction where hydrogen and oxygen are combined to produce water. This means that the waste product is completely harmless – thus eliminating the polluting effect of carbon dioxide.
By R.Dervisoglu – Own work, based on http://en.wikipedia.org/wiki/File:Solid_oxide_fuel_cell.svg, Public Domain, https://commons.wikimedia.org/w/index.php?curid=19314043
There are other advantages too – for example, they are more efficient than diesel or petrol engines and, unlike other cells (batteries) the current stays constant, it does not dip or reduce over time. Well, it stays constant as long as there is fuel to be reacted.
It sounds great doesn’t it, so why are fuel cells not part and parcel of the world now? Well, they do have a few disadvantages as well. For example, they are expensive to manufacture. However, as I am sure you are aware, manufacturing costs do come down as technology is more widely available and readily used, so I would expect to see changes to the price in the future.
However, the main stumbling block is to do with hydrogen. It is not readily available, and it is dangerous – as it is explosive. So any vehicle powered by a fuel cell needs to have a safe way of storing sufficient hydrogen to allow a decent length journey to take place. At the moment, cars with fuel cells need to have hydrogen tanks that can store the gas at getting on for 700 atmospheres – how would you feel sitting above that?!
However, a new product, NU-1501 has been manufactured that allows hydrogen to be stored at much lower pressures. The substance is like a sponge with an incredibly high surface area and is a metal-organic complex. However, unlike a sponge it has a very ordered structure but can be ‘squeezed’ to release the gases stored in it. It sounds promising – could it prove to be the tipping point?
This article was inspired by a BBC article “Climate change: ‘Bath sponge’ breakthrough could boost cleaner cars” that I read a few days ago (https://www.bbc.co.uk/news/science-environment-52328786)