It seems strange that, nowadays, we continue to extract oil and burn it to generate electricity. A primitive legacy, which not only pollutes but is also expensive and fuels wars. There is an innovation that could make both current fossil fuels and some future energy sources totally obsolete, making solar and wind much more affordable and environmentally friendly. Ladies and gentlemen: CO2 batteries.
First of all, what are CO2 batteries?
A CO2 battery is a technology that converts energy from carbon dioxide by moving it in a closed loop. When the battery is discharged, all that remains is a huge dome filled with carbon dioxide at atmospheric pressure. To charge it, CO2 is first pumped out of the dome and compressed (which heats it). The heat is removed and stored in a device known as TES (Thermal Energy Storage), which turns CO2 into a cold, thick liquid that is then stored in tanks. Energy is now stored as heat in the TES and as pressure in liquid carbon dioxide tanks.
Discharging the CO2 battery is a two-step process.
First: the tanks are opened, which release the liquid CO2 at high pressure. When it escapes, the pressure decreases and causes the CO2 to return to its gaseous state (this causes it to expand). The gas is then passed through the TES, where it is heated and expands further. This double expansion creates colossal pressure, which is channeled through a turbine that spins a generator and produces electricity. The CO2, now at atmospheric pressure, is then pumped back into the dome, ready for battery charging.
It seems complicated to me, and given the required dimensions I have an idea that we will hardly see CO2 batteries that power electric vehicles-
So what makes these CO2 batteries unique?
Wind and solar are excellent, creating loads of energy with far fewer emissions than other technologies. The wind doesn't always blow, however, and the sun doesn't always shine. I will never tire of repeating it: batteries will be needed to store energy when it exceeds, and discharge it when needed. The current battery of choice for this process is the lithium-ion battery, the same technology that powers electric vehicles, laptops and phones.
CO2 batteries are simply better than lithium batteries for use as storage systems. For four reasons: cost, environmental impact, scalability and life cycle.
Cost
Lithium batteries are expensive, and most EV owners will tell you this. Batteries for solar and wind energy storage are even more expensive, because they are larger in size. CO2 batteries, on the other hand, can be created from readily available materials at a fraction of the cost, making wind and solar farms much cheaper.
Environmental impact
Lithium-ion batteries are not the “environmental angels” they seem. Building them requires a lot of energy and logistics, so they also have a certain carbon footprint (check it out to this research published in Nature). Not to mention the mining activity necessary to access this raw material, and the geopolitical problems that it will cause in the next few years. On the other hand, CO2 batteries can be built using readily available recycled materials. This makes their impact on our planet much lighter.
Scalability
As you may know, we are plunging headlong in a battery crisis. Material supply chains (and the world situation) are unable to handle the growth in demand for batteries, which is why the price of materials such as lithium, nickel and manganese has skyrocketed.
CO2 batteries have no such problems. Thousands and thousands of these batteries can be built quickly and easily - theoretically, the world could embrace this technology very quickly.
Life cycle
Lithium-ion batteries don't last forever, as every iPhone owner knows. The internal structure of the cell deteriorates with each charge and the battery capacity reduces over time. Modern high-end lithium-ion cells can handle up to 2.000 charges, but less expensive versions can survive a few hundred charges. In summary? Lithium ion batteries will need to be replaced approximately every 10 years.
Again, CO2 batteries would be far superior, as they do not degrade. In theory, these batteries could last hundreds of years with regular maintenance.
So why don't we immediately adopt CO2 batteries?
Nobody is perfect, and therefore not even CO2 batteries. In terms of efficiency, for example, they are lower than lithium ion ones. The latter have an efficiency of 99%: if you charge one with 1 kWh of power you will get 0,99 kWh. CO2 batteries have maximum efficiency of “only” 80%. At the moment, therefore, to obtain the same energy we would have to build more plants, and goodnight to some of the advantages that I have listed so far.
However, some does not mean all. There would still be a saving. With new generation (and larger) solar parks they can still improve wind and solar energy, mitigating the environmental impact. Indeed, it would be the beginning of a domino effect.
Renewable revolution
The transition to a network of CO2 batteries could kickstart a renewable revolution. Why bother increasing (or reintroducing) nuclear energy, or keeping gas-fired power plants running when we could get much more energy (and much less ecological impact) from a solar or wind farm powered by CO2 batteries?
Let's give time to time: CO2 battery technology was conceived only in February 2020, and since then the first functioning systems have already been available. Such rapidity of development justifies a little confidence.
Maybe we don't need a fusion reactor or science fiction technology to save the planet. Perhaps an already available technology can produce incredible results surprisingly quickly, if properly supported.
How about?
