Much of our global greenhouse gas emissions and air pollution come from energy used in cities. Transportation and buildings, in particular, are energy-intensive sectors, as Dr Jan Rosenow states.Transitioning away from fossil fuels is not straightforward, no matter where we are in the world. Godwin Aigbokhan refers to the Nigerian ‘funnel’, where less than 4 GW of the 13 GW electricity generated gets distributed. As a result, there are millions of oversized diesel generators. Dr Jemma Green contrasts this with Germany, which has a high penetration of renewables, but also high electricity costs and carbon emissions due to its grid design and stabilisation requirements.We are now having to change all the wheels - figuratively - after the airplane has taken off. We must move to low carbon sources and tackle efficiency, which includes using energy that is produced, but currently not consumed. We must also look to storage, and to making dispatchable alternatives scalable and cost-effective. Jan sees green hydrogen as potentially playing an important role here, not least in high temperature applications in industry.Both Jemma and Jan talk about the importance of when and where electricity is generated and utilised. Jemma recommends time- and place-based price signals, increasing renewable energy supply only where it matches demand, deploying storage, enabling close proximity trading, and having a more cellular, efficient grid. Shifting from a centralised to a peer-to-peer distributed model is a major urban opportunity. Blockchain-based technology can enable energy communities where electricity - and even the payment - travels shorter distances. Jemma’s company Powerledger is implementing solutions in the global north and south.Aside from physical and digital infrastructure, all three speakers talked about policy, with Europe as the “learning laboratory”, to quote Jan. This includes net metering, smart electricity tariffs based on supply and demand, carbon pricing, and product efficiency. We need ways to increase renewables without wasting energy, making it unaffordable or indeed creating more backlash and knee-jerk reactions from consumers and industry.Speakers:Godwin Eni Aigbokhan - Former Head of Energy and Environment Competence Center, Delegation of German Industry and Commerce in Nigeria, AHKDr Jan Rosenow - Principal and European Programme Director, Regulatory Assistance ProjectDr Jemma Green - Executive Chairman & Co-Founder, PowerledgerLinks:UN Habitat on Future of Energy