The race for the development of renewable energy storage solutions has increased in recent years, especially as the climate crisis and the need for renewable alternatives to fossil fuel energies continue to grow. While there are several contenders for the front runner in storage solutions, two stand out from the group: the use of grid-scale batteries, and kinetic (or flywheel) energy storage solutions. Both are attractive for different reasons, and both have drawbacks working against them, but the popularity of both leaves them worthy of discussion in the sustainability conversation.

Both have many benefits to them. Batteries are a renewable take on storage technologies that we are all already familiar with and have some degree of understanding of how they operate and store energy. Additionally, continued technological advancements have made the components used much cheaper, and so they are far more cost-effective to produce, while each battery is also able to hold a sizable amount of energy. On the other hand, flywheels are favourable thanks to their minimal running costs once installed, use of recyclable parts, and the long lifespan that some are developed with makes them beneficial both in terms of economics and environment. Both are also suitable energy storage solutions thanks to the fact that both can be accessed on-demand when electricity use is at its highest, and neither relies on weather conditions to store or generate any energy.

However, with the good comes the bad, and despite these benefits, some problems come with both types of energy storage. Despite the technological developments that have made batteries cheaper and easier to produce, many batteries still contain lithium, which requires a complex evaporation process that uses briny seawater to obtain, which in turn can damage local freshwater supplies. Many also contain heavy metals such as cobalt, which have been repeatedly proven to damage the environment, plants, animals, and human health. Furthermore, batteries built on an industrial scale, as is common, require a large area of available land to build upon, which is limited while there is an ever-growing global population. Alternately, the major drawback of the design of flywheels currently is the expense that it costs to initially build and set up the flywheels, despite efforts to reduce costs and streamline the process. However, batteries require continual upkeep, whereas flywheels require no maintenance once set up.

Of the two technologies, despite the financial cost benefits of batteries, the cost to the environment is too large to make them a truly sustainable option. Not only that, but the longevity of flywheels once set up, their lack of maintenance, and the fact that they can be used to both generate and store energy make them a natural winner. Amber Kinetics, the world’s leading developer of long-duration flywheel energy storage solutions, is working to develop the technologies and materials used in creating flywheels to reduce the initial build costs and make them a near-perfect solution to the energy storage problem as we move our global energy focus away from fossil fuels to fully invest in renewables.