By: Sandy Tung, Programme Manager for Sharing Cities

Cities play a crucial role in shaping the climate agenda, accounting for about 65 percent of global energy demand and 70 percent of energy-related CO2 emissions. Of that, buildings are responsible for 40 percent of energy consumption and 36 percent of CO2 emissions in the EU. As urban populations continue to increase, the challenge to shift to more sustainable development, and decouple increasing energy demands from greenhouse gas emissions, has never been more pressing.

National and regional carbon reduction targets have led to a big shift in how energy is produced, distributed and consumed at every scale. Rapid electrification of our transport and heating systems is essential in achieving these targets, and our ability to supply electricity through local, renewable power is a crucial part of that effort. However, shifting to greener energy production alone is insufficient in meeting our climate goals quickly enough. To support faster decarbonisation at lowest cost, we need a smarter energy system – one that integrates heat, power, transport and buildings, and can optimise supply and demand with storage and flexibility. According to the Mayor of London’s Zero Carbon London plan, if we further decarbonised energy systems and buildings UK-wide, we could reduce carbon emissions by an extra 30 percent.

COVID-19 has also forced an unforeseen shift in energy patterns. To support social distancing, people are spending more time in their homes, and our relationship with energy and the way we use buildings is also changing. These patterns may well continue long after the peak of the pandemic. Investing in a smart, local and fairer energy system must be at the heart of any recovery plan, and indeed any long-term development strategy.

Energy-saving in action

The Greater London Authority leads Sharing Cities, a collaborative European smart cities programme of 34 partners across the public, private and academic sectors. Since 2015, we have tested technologies such as electric and shared mobility schemes and street sensors, and have developed data-sharing platforms that integrate these solutions for increased impact. Our work shows how thoughtfully designed, integrated, open-source solutions can improve the wellbeing of citizens as well as the sustainability of our cities.

Sharing Cities also trialled deep energy retrofits and smart energy systems, which were rolled out in three cities: Lisbon, Milan, and the Royal Borough of Greenwich in London. These energy upgrades are already showing impressive results. Lisbon’s historic city hall is receiving 36 percent energy savings and a 50 percent reduction in total electricity use from the grid. In Milan, energy consumption has been reduced by 60 percent in the buildings that were retrofitted.

In the Royal Borough of Greenwich, where 41 percent of the borough’s emissions come from housing and 10 percent of households are in fuel poverty, Sharing Cities went beyond standard retrofit and repairs by completing a deep energy retrofit on two large housing estates, combining energy-efficiency measures with low carbon technology, connected devices and smart controls. This has led to greater savings, equivalent to 667 homes’ energy usage a year so far.

In our latest playbook on deep energy retrofits, we summarise the lessons learned and share our insights on how these methods can be replicated across municipal buildings, public housing and private developments to help reduce energy use whilst improving comfort levels for people living and working in those buildings. We also share some advice on navigating the tricky political, regulatory and cultural challenges to implementing these ambitious and complex schemes.

Old cities like London, Lisbon and Milan have a large amount of old building stock with inefficient heating and cooling systems. This presents an enormous opportunity to reduce our environmental footprint with retrofits. In London, to meet our carbon targets set by the Mayor of London, we will need to retrofit almost 160,000 homes a year by the mid 2020s – requiring £10 billion (US$13 billion) of investment by 2050. There’s still a long way to go. With the recent announcement of the UK government’s £3 billion energy-efficiency plan for homes and public buildings, our playbook makes the case for greater investments retrofits that leverage smart technology for greater impact.

There’s no better time than now to roll up our sleeves and get retrofitting!