Seasoned dealmakers going back to school, Wall Street banks hiring from NGOs, bankers looking beyond the bottom line and thinking like management consultants — the battle for the $7tn-a-year needed to finance the push to net zero is presenting unique challenges to investment banks that many are not prepared for.

Banks have rushed to create teams of specialist dealmakers to focus on ESG, sustainability and clean energy transition over the past year as capital markets are expected to provide the bulk of financing in the quest to tackle climate change. But most lack expertise and need to hugely shift their businesses to meet demand, according to specialists.