Inside Rondo’s European debut with new CEO Eric Trusiewicz

Rondo Energy’s hot bricks are crossing the pond. 

The thermal storage startup uses electrical heaters to convert intermittent renewable energy into industrial heat, and recently announced a new round of $80.6 million (€75 million) in non-dilutive funding to expand its European presence. 

• The top line: The capital is slated to fund three European projects, which are the first large-scale commercial projects Rondo has disclosed since it raised its $22 million Series A round of financing in early 2022. According to the company’s new CEO Eric Trusiewicz, Europe’s decarbonization policies combined with its desire to achieve energy security and get off natural gas create an ideal context for the adoption of Rondo’s heat batteries.
• The nuts and bolts: The capital comes in the form of a grant from Breakthrough Energy Catalyst and a loan from the European Investment Bank. The three projects it is slated to fund will be in three countries — Denmark, Germany, and an unspecified third — and in use across three industries: green industrial waste, chemical production, and the food and beverage sector.

Europe is a high-priority market for Rondo, as the announcement of the three new project highlights.

“There’s a broader industrial decarbonization tendency in the continent that has been part of government policy for longer than it has in the U.S.,” Trusiewicz told Latitude Media, adding that some of the high-profile legislation in the U.S. is really the country’s effort to catch up to Europe.

But the U.S., where Rondo is headquartered, is where the company installed its first, smaller-scale commercial project: a battery that converts renewable energy to heat, then uses what is essentially a hot brick to store that high heat until Calgren Renewable Fuels is ready to use it at its California ethanol production facility. 

And Rondo has other, undisclosed commercial projects under development in North America as well.

Speaking as the 2024 election season heats up in the U.S., Trusiewicz added that the country’s future policy environment “will be an important consideration for how competitive North America is for this type of technology deployment.”

Trusiewicz has been involved with Rondo since it was “five people in a garage,” but was just appointed as CEO last month. He succeeded co-founder John O’Donnell, who has in turn become chief innovation officer.

While Rondo is furthest along when it comes to commercialization, thermal batteries as an option for decarbonizing industrial processes is gathering steam more widely. In February, the industrial thermal battery competitor Antora Energy raised a $150 million Series B aimed at scaling up manufacturing. And Fourth Power, which relies on liquid tin to store heat that is then converted only into electricity, raised a $19 million Series A round in December.

The projects 

The range of industries and locations chosen for Rondo’s three European projects was an intentional demonstration of the company’s technology, Trusiewicz said. 

In Denmark, for example, GreenLab is developing a circular industrial park to demonstrate how energy waste can be reduced in industrial applications, and is planning to install Rondo’s heat batteries to provide high pressure steam to a combined heat and power generator. The CHP generator will in turn provide baseload heat and power for multiple companies, including one producing low-carbon biogas.

In Germany, chemical manufacturer Covestro is planning to introduce Rondo’s heat battery to provide the heat needed to create steam at one of its facilities; the third, undisclosed project is for a producer in the food and beverage sector that charges the batteries using on- and off-site solar. 

“Breakthrough and the investment bank are putting in financing sufficient to cover the capital investment of those projects,” Trusiewicz said. “Rondo is constructing the projects, and then the customers will be paying over a number of years for us to recuperate the investment.” 

Installing the heat batteries and receiving availability payments from customers, which handle the electricity procurement and operations — or storage-as-a-service, as Trusiewicz calls it — is one of three ways Rondo makes its product available to customers. A customer can also just buy the equipment directly, or have Rondo handle everything from the battery installation to renewable energy procurement. 

Breaking through the gap

With the new funding, Trusiewicz said Rondo is successfully plugging the “famous” funding gap between when a startup develops its technology in the lab, and when it deploys its first-of-a-kind projects; investors tend to be less eager to finance the latter. 

“Infrastructure investors aren’t keen to take venture risk, banks want to wait until the technology is more mature, and customers want to see something operating before they buy it for large scale infrastructure assets,” Trusiewicz said. “So that [$80.6 million] really comes in at the perfect time for us.”

As a nonprofit arm of Breakthrough Energy, the Catalyst platform’s aim is to come in with money exactly at that moment when first-of-a-kind projects need capital to get off the ground. The organization is currently focusing on clean hydrogen, long duration energy storage, sustainable aviation fuel, direct air capture, and manufacturing.

In 2021, Catalyst launched a partnership with the European Union specifically to develop large-scale climate projects like Rondo’s.

“[Catalyst] brought us in conversation with the European Investment Bank,” Trusiewicz said. “Of course, we had to have that conversation independently… But that existing relationship and introduction made that go faster.”

(Breakthrough also supports Rondo Energy through its venture capital arm, which led its Series A funding round alongside Energy Impact Partners.) 

With that support, Trusiewicz anticipates scaling the technology and the company quickly, given what he characterized as the market’s “accelerating appetite for adoption.” 

“The company is going faster than we could ever have imagined,” he said. “We raised the Series A; we raised follow-on capital; we raised this non-dilutive capital. The amount of capital demand goes hand-in-hand with deployment of technology, so we'll continue to raise capital to meet the demand for growth for the company.”