Terra Innovatum, GSR III Combine Businesses, Bring Micro-Modular Reactors to Market

Terra Innovatum's SOLO micro-modular reactor generates low-carbon stable electricity and heat across multiple sectors, such as industrial manufacturing, mining, rural and remote communities, defense installations, AI data centers, and more.

Terra Innovatum will assemble its SOLO reactors with off-the-shelf components and, once factory-assembled, fuel them with 4.95% low-enriched uranium to reduce supply chain issues and accelerate deployment. The compact, cube-shaped microreactor design was finalized in October 2024 and can generate 1 MWe of clean power. It features ultra-long refueling intervals of 15 – 45 years, depending on the configuration.

Rendering of SOLO microreactor plaza; image credit: Nuclear Regulatory Commission

“We are excited to take Terra Innovatum public, which will mark a major milestone in our mission to make nuclear power simple, safe, and scalable,” said Alessandro Petruzzi, Co-Founder & CEO of Terra Innovatum. “Our reactor, SOLO, aims to bring off-grid, zero-carbon power to industrial, remote, and high-demand sectors. With 1 MWe at a time for a single SOLO unit, we can leverage our modularity to power up to one GWe with a lower footprint of a similar GWe plant.”

Each SOLO unit leverages helium gas cooling to eliminate meltdown risk, explosion potential, and proliferation. It’s contained within a 2.5-meter-thick concrete housing, which removes emergency planning zone requirements and ensures that public radiation exposure is far below legal safety limits. The company submitted its formal regulatory engagement to the Nuclear Regulatory Commission in January 2025, with plans to achieve commercial deployment in 2028.

Transaction Details

Terra Innovatum and GSR III Acquisition Corp. signed a business combination agreement that allows Terra to enter the Nasdaq as a publicly listed company under the “NKLR” ticker symbol. The transaction values Terra Innovatum at $475 million, with its micro-modular reactor development and commercialization being supported by up to $230 million as it enters public trading. The business combination agreement is scheduled to close in late 2025.

"With trillions in capital seeking clean, scalable solutions, nuclear energy is finally receiving the recognition it deserves,” said Giordano Morichi - Partner, Chief Business Development Officer & Investor Relations. “Our decision to go public reflects the maturity of our technology, enabling a rapid go-to-market response to the growing demand for low-carbon energy. SOLO is a platform designed for global scalability and impact. This transaction marks the beginning of Terra Innovatum's global deployment journey, offering an opportunity to invest in nuclear energy."

Microreactor Technology

Turbomachinery International spoke with Rolls-Royce about microreactor technology: compact, portable reactors that produce thermal energy for use as heat or electrical power. Potential use cases for the technology include, “The first one is the terrestrial variant for supplying power to different applications on Earth; and the second is the space micro-reactor that has potential applications for the lunar base as part of the space program and, in the longer term, for power and propulsion applications on satellite and deep-space missions,” said James Montgomery, Chief Design Engineer, Novel Nuclear at Rolls-Royce.