Fireworks signs for 5MW of Nvidia B300 capacity at Era4

Fireworks will lease 5MW of direct-liquid-cooled capacity powered by Nvidia Blackwell Ultra HGX B300 GPUs at Era4's Chesterfield data center in Derbyshire, Data Center Dynamics reported Nov. 3.

Fireworks will initially aim the Chesterfield capacity at financial services, insurance and life sciences customers, according to Data Center Dynamics. The company runs an open-model AI training and inference platform and already has deployments in Germany and Iceland. The site uses HPE ProLiant Compute XD685 servers inside an HPE AI Mod POD modular data center.

Allocators underwriting the 5MW face on-site fuel and operations risk rather than a new grid interconnection. The Chesterfield site runs primarily on landfill gas captured on site, with a grid connection for backup. Era4 owns and operates the infrastructure, including behind-the-meter power generation, chief executive Tom Humphreys said.

Era4, which launched last year as Carbon3.ai and rebranded earlier this year, said in September 2025 that its platform would eventually comprise 100,000 GPUs across more than 30 locations. In October, Forum Edge signed a $94.4 million Nvidia B300 reservation with Fireworks, a 36-month Dallas capacity deal, as Private Infrastructure Daily previously reported.