Swiss Startup Invents Unique Energy Storage Solution

David Fessler By David Fessler
Energy and Infrastructure Strategist

Alternative Energy

Our electrical grid is the largest, most complex machine ever designed. And over the past century, engineers have continued to modify and improve on that design.

However, the grid requires that the supply of power be equal to demand at any given time.

This presents a problem when one of the peak periods of demand for electricity is in the late afternoon and evening… when energy produced by solar and wind power is decreasing.

The ability to store electricity produced during the day for use at a later time solves this problem. That’s why adding energy storage to the power grid is critical.

Each storage technology is unique. In fact, my last article focused on a unique energy storage system that’s tailor-made for the cold storage business.

But there are other exciting energy storage technologies under development, one of which I want to share with you today.

Just a Crane and Concrete

Engineers are always looking to improve things. This includes the ability to store energy for longer periods of time.

Battery-based energy storage systems can produce energy for four to five hours at most. Pumped hydroelectric systems can produce energy for 10 to 12 hours.

But what if we could store energy for days or even weeks? Or for an entire season? That would give residents the ability to heat their homes through the winter with electricity that was produced and stored during the summer.

Well, Swiss startup company Energy Vault has an interesting and completely new idea. It plans to build an energy storage system using a 400-foot-tall crane.

The crane will have six arms, each of which will be capable of lifting 53-metric-ton concrete-filled cylinders.

The crane will stack the cylinders in a circular pile around the tower. It will do this during periods of excess energy production.

During periods of peak demand, the crane will lower the blocks back to the ground. Electricity will be generated during the blocks’ descent.

The cost of this storage solution is expected to be roughly $150 per kilowatt-hour. Compare that with today’s battery-based systems that cost between $280 and $350 per kilowatt-hour.

Energy Vault’s crane-based system will be able to store about 20 megawatt-hours’ worth of electricity. And there will be no degradation over time.

The system is expected to be roughly 85% efficient. That compares with 90% efficiency for a battery storage system.

Additionally, the biggest expense isn’t the crane itself – as some might guess – but the concrete blocks.

Unsurprisingly, Energy Vault has a unique solution to this problem too. It uses used gravel, cement and other building waste, and recycles them for use in the blocks.

In an upcoming article, I’ll discuss another unique form of energy storage that uses off-the-shelf materials to store electricity.

Not all of these new and interesting energy storage systems will pan out. But it’s clear that the future is bright.

You can bet I want to invest in the most promising prospects… as should you.

Good investing,

Dave