Paris-based climate technology startup Epyr has raised €15 million in an oversubscribed Series A funding round led by SlateVC. Existing investors AENU, Daphni, WEPA Ventures, OVNI Capital and Aurum Impact also participated in the financing.
The funding will support the deployment of additional thermal energy storage systems across European industrial facilities, beginning with a planned 35 MWh installation for French paper manufacturer Papeco.
Founded in 2024 by Bastien Oggeri and Léa Dardenne, Epyr develops thermal energy storage technology that enables industrial manufacturers to replace fossil fuel-based heating with electricity. Its systems are designed to supply high-temperature process heat while allowing industrial customers to manage energy costs.
Epyr’s technology uses electricity during lower-cost periods to power resistance heaters that heat air and transfer energy into firebricks. The stored thermal energy can subsequently be released to supply industrial processes, including steam generation, when required.
The company combines thermal storage equipment, system integration and energy management with optional third-party financing through a Heat-as-a-Service model. This approach allows industrial customers to access electrified heat without necessarily financing the equipment themselves.
Epyr’s first industrial installation was inaugurated in May 2026 at WEPA Group’s paper mill in Troyes, France. Built and commissioned in less than six months, the unit supplies approximately 25% of the facility’s steam requirements. The system had already entered commercial operation before its inauguration.
The company is now preparing a 35 MWh thermal energy storage project at Papeco’s Orval-sur-Sienne facility. The planned installation is designed to replace the site’s natural gas consumption with electrically generated process heat.
Before its Series A, Epyr announced a €3 million pre-seed funding round on February 3, 2025, co-led by AENU and Daphni, with participation from OVNI Capital, WEPA Ventures and several business angels.
The latest financing will allow Epyr to pursue further industrial installations as it expands its thermal storage offering beyond its initial deployment in France.
