Batteries rarely come up in discussions about sustainable energy. People tend to think of only solar panels, wind turbines, and other devices that capture energy from the atmosphere. However, the fact is that without a form of energy storage, the vast majority of the captured energy would be wasted. Plus, without storage, the environmental limitations of renewable energy will be insurmountable. If we can only use solar energy when the sun is out or wind energy when the wind is blowing, then we’ll never be able to power civilization over the long run.
The unfortunate effect of that common oversight is that people aren’t discussing how we can make renewable energy storage as sustainable as renewable energy capture. This means that chemical batteries are still mistakenly assumed to be the only option when storage comes up in a debate. The problem is that chemical batteries themselves are not sustainable and are harmful to the atmosphere.
Fortunately, there is an alternative. We need to get people talking about it more often.
The Problem with Battery Energy Storage
Battery energy storage is a messy business. Or, stated more properly, battery energy storage is a dirty business. Lithium, as one example, is mined primarily in South American salt brines. The lithium-mining process badly pollutes the water systems in those areas, rendering much of their fresh water undrinkable. Cobalt mining in the Democratic Republic of Congo is tangled up with severe pollution and child labor.
The waste created by battery production is not easy to recycle. One study found that only 2% of Australia’s lithium-ion waste was recycled, and Australia is one of the world’s biggest producers. Recycling the batteries means physically shredding them apart, which requires a lot of energy and waste.
Traditional battery energy storage is not a viable path to global renewable energy. So, let’s talk about options.
Eco-Friendly Alternatives to Battery Energy Storage
There are several eco-friendly alternatives to battery energy storage, each with its pros and cons.
- Compressed air energy storage
- Hydrogen fuel cells
- Ice storage technologies
- Pumped hydro storage
- Thermal storage
- Mechanical storage (including flywheel energy storage)
There may be a place for each of these alternatives, but flywheel energy storage seems the frontrunner and most likely long-term solution.
What is Flywheel Energy Storage?
Flywheels are a form of kinetic energy storage. The basic technology has been around for a long time (starting with the potting wheel). Still, modern flywheel energy storage is a highly advanced, efficient, and fascinating approach to mechanical energy storage. They use dual-function motors that spin mass around an axis and store the resulting energy to be used later. These devices are massive and heavy, requiring magnets to support their weight.
Flywheels have long life spans (up to 30 years), do not require heating, ventilation, or air conditioning, work at greater than 86 percent round trip efficiency, and are reliable in extreme heat and cold. They require no carbon-producing mining and are very recyclable.
Energy storage is a significant part of the world’s quest for renewable energy. Flywheel energy storage is possibly the best sustainable solution. The math is simple.