tem

tem builds AI-native infrastructure for energy transactions, aiming to be the 'Stripe of energy' by automating how businesses buy, sell and manage electricity while stripping out hidden fees and inefficiencies in wholesale markets. Its Rosso platform automates energy transactions, and its RED neo-utility gives businesses and brokers a modern interface to contract and manage energy. Founded in 2021 and based in London, tem facilitated over 2TWh of transactions for 2,600+ UK customers in 2025 and exceeded $300M in annualised gross transaction value. It raised a $75M Series B in February 2026 led by Lightspeed, bringing total funding to about $94M, with backers including Atomico, AlbionVC, Hitachi Ventures and Voyager Ventures.