Rondo Superheated Brick Energy Storage Technology Backed by Microsoft and Aramco

Aug. 18, 2023
The Rondo Heat Batteries can store energy at half the cost of green hydrogen and chemical batteries, and the company hopes their system will reduce energy consumption rates across the industry

Rondo Energy has successfully raised $60 million in financing to advance the rollout of its Rondo Heat Batteries on a global scale. The funds, which will help Rondo Energy develop and build storage projects around the world, were provided by several investors, such as Microsoft, Rio Tinto, Aramco Ventures, and SABIC.

“We are honored and excited by this opportunity to go faster by working with these leaders. Our Strategic Investor Advisory Board will help Rondo focus on the simplest, fastest ways to power their operations with low-cost clean energy and shape our priorities for ongoing research and development,” said John O’Donnell, CEO of Rondo Energy.

The Rondo Heat Battery is a low-cost, zero-emission industrial technology that utilizes bricks to store and deliver continuous heat from intermittent power sources, such as wind and solar.

To start, electricity from the intermittent power sources is collected and turned into heat using electrical heating elements similar to those used in toasters or ovens. The electrical heaters convert the electrical energy into heat at 100% efficiency.

Next, the electrical heaters begin to warm the objects around them through thermal radiation – in this case, thousands of tons of bricks. These bricks are heated up to 1,500°C and are capable of storing energy for days with less than a 1% loss per day.

When the heat is needed, air flows through the brick stacks, superheating them to over 1,000°C. The heat delivery rate is adjusted by changing the airflow, and the heat at the outlet is delivered at the required temperature through a system of automated AI controls. The air used to heat the bricks will also be recycled back through the system, minimizing the potential for heat loss.

From here, the heat gets delivered at the exact temperature and pressure required, either as superheated air or superheated steam, to meet facility demands.

By using materials already made at large scale for more than a century – brick and iron wire – Rondo has helped reduce the safety, durability, and supply chain risks common with other storage technologies. The Rondo Heat Batteries can store energy at half the cost of other technologies, such as green hydrogen and chemical batteries, and the company hopes their system will reduce energy consumption rates across the industry, which currently consumes a quarter of all global energy.

“To tackle our climate challenge, we need tools to build big, low-cost, clean energy infrastructure fast.  The Rondo Heat Battery is one of those tools. This investment will help us grow our capacity to meet customer demand and begin to build at scale,” added O’Donnell.