Background 

Sustainability is a central focus for real estate investors and occupiers, driven by global, national, and local ESG commitments as well as corporate led initiatives. Whether through the UK’s 2050 Net Zero target, revised Local Plans, or company-specific goals, new sustainability targets are being set with increasing frequency.

The BNP Paribas Real Estate Green City Index, utilising Next X data, assesses the performance of UK cities based on key sustainability indicators, providing a clear view of which cities are advancing towards more sustainable objectives.

Encouragingly, all sustainability measures we track have shown improvement in recent years from a national perspective. For instance, according to the latest data releases:

• Local Authority (LA) average CO2 emissions per capita dropped by 6.5% year-on-year to a new record low in 2022. (1)
• Residual household waste per household in England decreased by 6.0% year-on-year in 2023, also reaching record lows. (2)
• UK renewable energy installations grew by 18.4% in 2023, totalling 1,495,000 sites. (3)

While most LAs align with this general trend of improvement, some stand out more than others.

Our Index examines 61 major UK urban areas, identifying both the top performers and those making the greatest strides. To ensure more fair comparisons, data is mostly analysed per person, household or kilometre.

To identify the top performing markets, data has been centred around five fundamental themes:

• Pollution / emissions
• Sustainable lifestyles (i.e. household recycling, commuting patterns)
• Infrastructure (including public transport usage, accessibility and electric vehicle infrastructure)
• Built environment (such as energy efficiency of real estate stock and renewable installations)
• Access to open space

Overall, Cambridge tops the rank for the second consecutive year, while Exeter and Gloucester have seen the most significant improvement in their ranking (from 6th to 2nd and 16th to 9th respectively). A noticeable divide exists between north and south, with eight of the top ten markets situated in the south, and York being the only northern city listed. This may reflect the fact that there are fewer carbon-intensive industries and a higher prevalence of service-based businesses, in the south (see Chart 1).

The list is also dominated by smaller cities (with Bristol being the exception), averaging a population of just 262,970, often reflecting lower density living and generally better access to green space.

Chart 1: BNPPRE Next X Green Cities Index – top ten cities

Top performers: Cambridge maintains its lead

Cambridge retains top position for the second consecutive year, thanks to strong performance across all five sustainability themes. This reflects the continued commitments from the city council, the private sector and residents to support the city’s sustainability efforts.

Access to open space plays a crucial role in providing a city’s “green lungs”, and Cambridge excels in this area. The city stands out for its protection and maintenance of city centre parks, surpassing most UK cities in both the number of parks and average distance from residents

Cambridge’s transportation network also supports a greener environment. Well-utilised park-and-rides reduces car traffic while its extensive cycle network promotes healthier modes of transport. The latest Census ranks Cambridge second in the UK for commuter cycling, at 8.1%, aided by ample bike parking, designated cycling lanes, bike-sharing schemes and local initiatives from the university.

The city’s environmental commitment is reinforced by its Climate Change Strategy with the goal of carbon neutrality by 2030, which has driven the integration of sustainability into urban development projects.

At Eddington, a growing neighbourhood in Cambridge, all buildings are designed to meet Code of Sustainable Homes Level 5 and BREEAM Excellent standards (4), incorporating solar panels, heat pumps and an underground waste/recycling system. Similarly, new life science and technology developments within Cambridge Science Park and St John’s Innovation Park are being developed with environmental initiatives at their core. These efforts have contributed to Cambridge’s above-average EPC ratings for both residential and commercial buildings.

Chart 2: CO2 emissions per capita, across the top 5 ranking Green Cities, against the UK average

Source: BNPPRE, ONS, Department for Energy Security & Net Zero 

As one of the UK’s leading cities for innovation and technology, Cambridge is poised for further rapid growth, especially among young working age populations, with a projected 5.6% increase in the 20-40 age group by 2030. With this will come carbon-intensive development which will need to be a monitored closely from a sustainability perspective.

Milton Keynes: an outlier or clear contender? Planning’s role in sustainability

Two towns developed under the New Town Act make the top ten within the Green Cities Index, Milton Keynes (MK) and Telford. While perhaps not obvious outperformers, their ranking is reinforced by convincing data.

• Milton Keynes is one of the fastest growing towns, driven predominantly by its widespread housing development. Newer residential stock tends to achieve a higher average EPC rating, as building technologies have improved efficiency. In the ten years to Q4 2024, 26.4% of EPC lodgements on residential premises in MK achieved EPC A or B, the highest of any major UK urban area. For context, the UK LA average over the same period was 15.4%. (6)
• Newer residential developments also support the growth of renewable energy installations. Many new towns are among top for the number of photovoltaic (PV) installations, with Peterborough leading the way with 10,966 PV installations (one for every 7.7 households). MK ranks seventh, with one for every 16.7 households, although boasts one of the highest national annual growth rates of 18.2% in 2023. (7)
• Urban green infrastructure is crucial. While most cities have naturally expanded their existing boundaries, new towns have the advantage of a blank canvas. In turn, they are often designed with open space and public parks as a focal point.

Cambridge’s Green Business Programme also targets local businesses, providing funding to 223 Small and Medium Enterprises to outline five-year net-zero plans (75 of which receiving funding to enhance the energy efficiency of their buildings). (5)

Measures like these support reduction of CO2 emissions and can help explain Cambridge’s strong ranking within the Green Cities Index. CO2 emissions (tCO2e) per capita in Cambridge dropped by 21.8% in the five years to 2022, reaching 3.2, outperforming the national average in both emissions and progression (see Chart 2). 

A clear shift toward Electric Vehicle adoption

MK has also become a pioneer in the adoption of electric vehicles, with widespread usage supported by an extensive network of rapid (50kW+) EV charging stations. MK has 77.7 publicly available rapid charging stations per 100,000 people, the highest among the top ten Green Cities, and more than three times the UK major city average of 22.3.

The map below illustrates the national divide in terms of EV ownership. The South East region dominates EV infrastructure, bar a few outliers which are generally boosted by largescale corporate usage. UK EV ownership rose by 36.2% in the year to Q2 2024, with London and the South East accountable for almost a third of UK ownership.

Map: Ultra Low Emission Vehicle ownership per 1,000 population by local authority, 2024

Source: BNPPRE, Department for Transport & DVLA 

Top-down strategy success: Bristol’s green agenda

It has now been a decade since Bristol was awarded European Green Capital, during which the city has implemented and improved the infrastructure projects that helped it win that award. Most notably the Bristol Heat Network, which allows retrofits, refurbishments and new builds the opportunity to effectively remove gas from their heating system and take the buildings fully electric. This has been an important step in the road to allowing developers to achieve Net Zero Carbon, as demonstrated by CEG’s work on the EQ building. 

Rupert Elphick, Associate Director in the Bristol Office Agency team adds “Bristol has always had a sustainable ethos, from the ground-up with occupiers targeting high ESG standards to secure the best talent and developers pushing the standards to achieve the best occupiers. This competition has peaked with developments like Welcome Building and EQ that now lead the market, both on sustainability credentials but also the well-being offering.”

This competition, coupled with the completion of several high-quality developments, has led to a strong uptick in Bristol’s prime office rents, increasing 40.6% since 2015 to now lead the Big Ten office markets at £48 per sq ft. Looking ahead, we expect low supply and build costs to play a more pivotal role – which could limit new build viability over the short-term but continue driving existing landlords to refurbish schemes to match the quality that has already been produced. 

Elsewhere across the city, initiatives launched by the city council have supported environmental improvements. For instance, Bristol City Council introduced the Clean Air Zone in November 2022 to reduce city centre pollution and encourage EV usage (which subsequently increased 72.7% between 2022 and 2024). This has also supported investment into Bristol’s cycling network. The council has announced plans for a further 3.5km of bike lanes, whilst many office buildings have adapted to support this movement, with end-of-trip facilities becoming an increasingly important function.

Donna Rourke, Head of ESG & Sustainability: “I’m always impressed by the power of local authority initiatives to drive sustainable change. Cities like Bristol and Paris prove that localised action can yield significant environmental gain. Bristol has expanded green spaces, rolled out energy efficiency programmes alongside renewable and recycling projects – cutting emissions whilst boosting biodiversity. Paris has created car-free zones, restricted polluting vehicles, expanded transit and cycling networks. These actions have reduced air and noise pollution while enhancing urban life, offering a strong blueprint for creating more sustainable cities.”

Conclusion

UK cities are making significant strides towards sustainability. Outperformers like Cambridge, Bristol and Milton Keynes somewhat lead the charge due to either innovative infrastructure, housing projects, electric vehicle adoption or city council initiatives. However, challenges persist across the UK, especially when it comes to balancing growth and expansion with carbon neutrality, underscoring the need for innovation and efforts to achieve long-term sustainability.

Sources:
1 BNPPRE, ONS, Department for Energy Security & Net Zero
2 BNPPRE, DEFRA, WasteFlowData
3 BNPPRE, ONS, Department for Energy Security & New Zero
4 University of Cambridge, Eddington Cambridge
5 Cambridge City Council
6 BNPPRE, ONS (Ministry of Housing, Communities & Local Government)
7 BNPPRE, ONS, Department for Energy Security & New Zero