Despite the widespread acknowledgement of the climate crisis and the need to reduce our reliance on fossil fuels, renewable energy still meets only around 10% of our annual energy needs. And a key reason is that renewable energy production is not consistent—it relies on the prevailing weather conditions and even the time of day, which means that without a means to store the energy, it cannot provide a reliable supply of power.
The solution has been to store excess energy, using the stored energy later to manage peaks in demand and troughs in production. The difficulty is in how that energy is stored. The two main approaches have been chemical and kinetic.
Chemical storage devices—batteries, in other words—will be familiar to everyone. Whether the integrated batteries in electronics, the replaceable batteries available from any store, or industrial batteries used alongside renewable power generation, the concept is the same. Essentially, power creates a chemical reaction within the battery. When the reaction is reversed, the battery then generates power.
Kinetic energy might be less familiar, but the concepts are probably not. Kinetic solutions have been used for thousands of years for energy storage. From ancient potters’ wheels to flywheel energy storage during the industrial revolution, and even children’s spinning tops, the basic principle is the same: Use energy to start something moving, then use the ongoing motion to power something else.
Both methods have their merits but also their disadvantages. Battery technology is rapidly improving, driven partly by consumer demand and also the recognition of its importance to renewable energy. However, some of batteries’ fundamental problems may never be overcome. The chemicals used all have drawbacks, from extraction processes that often carry a large environmental and human cost to the difficulties of chemical disposal at the end of life. And while the technology and efficiency are improving, batteries are likely to remain impractically large, slow to charge, and with relatively short lifespans, for some time to come.
Flywheel technology, still in its infancy at this scale, is more expensive, and has to overcome the difficulties imposed by the laws of physics. The biggest enemies of flywheel energy storage are the air resistance and friction that can slow the wheel. However, like batteries, flywheel technology is rapidly improving. Using magnetic bearings and running the wheels in a vacuum increases efficiency. Amber Kinetics, for example, boasts a flagship product that offers at least 86% efficiency.
Flywheels also have the benefit of being more environmentally friendly. They can be made largely or entirely from recyclable materials, meaning there is no environmental impact, and their design means a much longer lifespan—typically up to thirty years with little loss in energy storage performance.
While the technology is still developing, Amber Kinetics have, since their foundation in 2008, established themselves as world leaders in the kinetic storage sector. With a strong focus on providing a sustainable and environmentally sound product, their M32 has been deployed in solar farms across the world. A highly scalable solution, it has seen use from Massachusetts, where it provides 128kW supply for a small town, to China, where it supports a 60MW solar power plant by storing and supplying stable energy.
Amber Kinetics’ systems have provided nearly a million kilowatt-hours, ensuring that homes, businesses, factories, and industries have a secure and reliable power supply, and doing it all without emitting any greenhouse gases. In other words, keeping the world running without it costing the earth.
Although batteries have shown that renewable energy is viable, it will likely be kinetic systems like Amber Kinetics’ flywheels that really solve the renewable energy storage problem.
