A school field trip in 1971 set me on my career to become an engineer. We visited what was then the largest engineering project ever undertaken in the history of the State, by the ESB at Turlough Hill in Co Wicklow.
A half kilometre-length tunnel was constructed deep through the granite between a man-made reservoir on the summit and the lower lake, driving hydroelectric turbines. Fully operational since 1974, Turlough Hill is, in essence, a massive battery recharged by using otherwise surplus power on the national grid to pump water up to the reservoir. The power station then can rapidly come on line to generate electricity at times when the grid is under stress. It thus smooths the national power generation and demand. The capacity is about 1,500MW hours. As a comparison, our record national demand was over 5,000MW in a peak surge just last December.
Our need for energy storage systems is increasing as we switch to renewable power sources, such as wind and solar. Today renewables supply up to about 40 per cent of our national power. Because of the need to balance load over weather vagaries, the ESB has recently announced two battery storage projects: one at Inchicore, Dublin, and the other at Aghada, Cork. In conjunction with Fluence (a joint venture between Siemens and AES) these batteries can together provide about 100MW hours before requiring recharging.
Energy storage has become a part of our everyday lives. We have all become much more aware of improvements in battery technology as we seek out the latest laptops, smartphones and devices. A significant proportion of their weight is the battery, and we all want lighter devices. The time available between recharging also influences our purchasing decisions, but multiple recharges reduce the life of the battery and it is often not possible to replace the battery in smart devices.
Range anxiety
When selling an electric vehicle (EV), showroom staff are frequently quizzed on the quality of the battery. We may be concerned by the length of time needed for a recharge, and have range anxiety over how long a charge can last. Colder and hot climates impact battery range, as power is used to keep the passenger cabin comfortable with heating or air conditioning. The lifetime of the battery controls the secondhand and resell value of an EV: as the capacity of a battery diminishes with multiple recharges, then so does the available range.
We can also worry about the physical safety. It is only a few years ago that the newly introduced Boeing Dreamliner was making headlines as its lithium-ion batteries spontaneously caught fire in parked aircraft leading to fleet groundings, Boeing pausing production and a Federal Aviation Administration safety review.
As we move to EVs, in the past year alone there have been well over a dozen reports of lithium-ion based battery fires, unrelated to collisions or accidents, when a parked EV or an EV being recharged has spontaneously caught fire. Following numerous battery fires, the Hyundai Kona EV underwent a worldwide recall in October 2020, followed by General Motors of the Chevy Bolt EV in November 2020. And if you have a boat trailer, be extremely careful not to dip your EV battery into the sea or a lake when loading or unloading!
Cobalt and lithium
Some commodity traders describe lithium as the new "white gold", as worldwide demand has accelerated due to EV batteries. Tesla has gone as far as to assert it will control its supply by owning its lithium mining operations. Cobalt is also used in most of the current generation of EV batteries, and accounts for a significant proportion of their cost. The Democratic Republic of Congo controls much of the world's cobalt production and there have been allegations of child labour and human rights abuses in its mining operations.
The EV industry is keen for myriad reasons to move to new battery technologies. A decade-old Stanford University spinout, QuantumScape, announced in December its new solid state battery technology for EVs using a flexible ceramic electrolyte. Current lithium-ion batteries in contrast use a liquid electrolyte. QuantumScape claims just a 15-minute charging time, but nevertheless a battery lifetime more than double that of current battery technology. The company went public last September and is now valued at about $16 billion (€13.3 billion).
Meanwhile, China's Contemporary Amperex Technology has announced a new EV battery technology with a 16-year or two million kilometre lifetime. In conjunction with Volkswagen, it is now building a plant at Erfurt, Germany, due to enter production later this year.
Ford, BMW and Hyundai are working with Solid Power, a Colorado based start-up, using a sulphide electrolyte solid state battery. Toyota, Samsung, Panasonic and LG Energy (a spin-off from South Korea's largest chemicals company) are all also rumoured to be researching solid state EV batteries.
The EU has just announced €2.9 billion support for a €11.9 billion European Battery Innovation project, with 42 collaborating companies and 12 member states (Ireland was not one of the proposer countries).
Energy storage technology is likely to remain a fruitful area of research and innovation for some considerable time.
