Lightspeed makes rare investment in European energy tech: ‘Strategic partnership was our absolute priority’

Lightspeed Venture Partners has led a $75m investment in tem, a fast-growing UK-based energy tech startup which is now looking to expand across the Atlantic.

One of the world’s most prominent VCs, Silicon Valley-based Lightspeed’s portfolio includes financial services platform Stripe, now valued at over $100bn, and Anthropic, the maker of the Claude large language model (LLM) which just raised $20bn at a $350bn valuation.

The bulk of Lightspeed’s portfolio are US-based software companies, however the firm has invested in European climate and deep tech as well, including in German fusion energy startup Proxima Fusion, Swiss hydrogen company NovaMea, and London-based carbon removal measurement firm Supercritical.

“We back a small number of companies each year…but tem stood out immediately,” said Paul Murphy, a London-based partner at Lightspeed Venture Partners, saying he saw a “clear market demand” coupled with sound economics.

‘Intentional about who funds us’

Joe McDonald, tem’s co-founder and CEO, told Impact Loop that bringing Lightspeed onto its cap table was as much a strategic move as a financial one.

“We’ve always been very intentional about who funds us, and for this round in particular, strategic partnership was our absolute priority,” McDonald said. “We needed a tier-one US generalist who understands what it takes to build a generational company.”

The Series B round also saw the participation of Hitachi Ventures, Voyager Ventures, and Schroders Capital, alongside existing backers AlbionVC and Atomico.

The funding comes at a time of rapid growth at tem, which more than doubled its headcount over the past year – from 56 to 127, per Dealroom data.

Cutting energy bills

Tem’s AI software stack helps businesses buy renewable electricity straight from generators like wind and solar farms.

Unlike utilities like Octopus Energy, which make money by buying and selling electricity, tem makes its revenues by cutting out the middlemen between an energy buyer and an energy supplier. This way, it claims to save up to 30% on a businesses energy bill.

International expansion

In 2025 alone, tem says it facilitated transactions for over 2,600 UK customers, including Boohoo Group, Fever‑Tree, Silverstone Circuit, and Newcastle United FC.

Tem will now use the fresh capital to expand its operations outside the UK – starting in Texas, US and Australia, where it says it is already in advanced talks with potential customers.

With the backing of some of the world’s top tech investors, McDonald appears confident about embarking on this next phase of growth.

“Lightspeed share our conviction that the energy system needs to be fundamentally rebuilt, and that only an AI-native company that is innovating at an infrastructure level can achieve that,” he said.