Heritage with innovation: How Citigen could help London’s historical buildings towards a greener future

In London’s historic Square Mile, where cobblestone streets meet modern ambition, and where centuries-old structures are seamlessly integrated with cutting-edge technology, a green revolution is quietly unfolding. The City of London Corporation has approved ambitious plans to upgrade several iconic office buildings, breathing new life into them while aligning with the City’s net zero goals – all while preserving their historic charm.

This is the vision taking shape as three large residential developments in the heart of the Square Mile undergo dramatic transformations. Far from mere facelifts, these renovations are designed to preserve the architectural heritage while significantly reducing carbon footprints. By retaining much of the existing building fabric, the City will avoid the carbon costs associated with demolition and new construction, cutting thousands of tonnes of emissions in the process.

Citigen, a unique energy centre at the heart of London’s energy revolution, has the potential to play a pivotal role in helping these historical buildings reach their sustainability targets. Located just a stone’s throw from the historic Smithfield meat market in Farringdon, Citigen’s district heating and cooling network offers an ideal, low-carbon energy solution that could complement the energy efficiency upgrades being made to some of these buildings.

Using boreholes that extend 200m below the city, Citigen taps into the natural warmth of the earth while recycling waste heat from power generation. This provides an additional 4MW of heating capacity and 2.8MW of cooling capacity—enough to power the equivalent of 13,600 homes. With this innovative system Citigen could help future renovations meet sustainability standards without compromising the architectural integrity of London’s iconic buildings.

Citigen also houses our UK Energy Control room, where more than 70 housing developments across the UK are remotely monitored and managed in real-time. These sites, connected through district heating schemes, are crucial in ensuring that thousands of homes and businesses across the country receive reliable and sustainable energy.

While Citigen directly manages 28 sites, including notable locations including the Barbican, the Guildhall, and The Museum of London, the potential for expansion is clear. As new renovation projects get under way, the opportunity to connect them to Citigen’s district heating and cooling network could further enhance their energy efficiency, making them even more significant contributors to London’s sustainability agenda.

By integrating Citigen’s advanced energy systems with London’s building upgrades, the City has the opportunity to achieve a unique balance between preserving its heritage and embracing its sustainable future. The fusion of old and new is more than just a clever solution to meet today’s energy needs — it’s a blueprint for how cities can transition toward a zero-carbon future while respecting their history.

As London continues to balance its storied heritage with a forward-looking sustainability agenda, the possibility of connecting upgraded buildings to Citigen’s energy infrastructure exemplifies how cities can marry their past with their future. The result would be a greener, more efficient city that remains rooted in its rich architectural history, all powered by innovative, low-carbon solutions.