海角视频

Early collaboration in the design stage and engagement with supply chain partners enables Temple Quarter Enterprise Campus to achieve a 25% reduction in embodied carbon.

The Temple Quarter Enterprise Campus for the University of Bristol is one of the UK鈥檚 largest city centre regeneration schemes. The development site is adjacent to Bristol Temple Meads station on a site previously occupied by a derelict and dilapidated Royal Mail sorting office. 

At the core of the development is the 38,500m2, 6-storey Academic Building (TQA1) being constructed by . This will be the eventual home of the University鈥檚 Business School, digital engineering research groups, Centre for Entrepreneurship and Innovation, and the Quantum Technologies Innovation Centre, while also providing dedicated facilities for enterprise and community partners.聽

In line with our commitment to reducing carbon emissions in construction, led by Sir Robert McAlpine, in partnership with 海角视频, demonstrates the benefits of early collaboration in the design stage and engagement with supply chain partners that share the same sustainability ethos and carbon reduction aspirations.

Low Carbon Design

The project demonstrated significant embodied carbon savings after a value engineering exercise conducted by 海角视频 in collaboration with Sir Robert McAlpine. The original design consisted of a 15m x 7.5m structural steel frame grid, answering the brief for maximum flexibility defined early in the design process. The grid size was reduced to 7.5m x 7.5m and the frame changed from hollow core precast planks supported on steel beams to a reinforced concrete solution slab solution. At ground floor level, 30m long steel trusses provided additional support for the large open-plan areas along with important rooftop elements. This change allowed for a more focused provision of flexible space, as the design had settled sufficiently to understand where these flexible spaces needed to sit. 

The newly optimised design had reduced upfront embodied carbon by almost half, from an estimated 29,560 tCO2e to circa 15,569 tCO2e (A1-A5). Approximately 70% (10,884 tCOe) of these remaining emissions were associated with the embodied carbon of the ready-mix concrete.  Reducing the carbon intensity of the concrete material therefore became a priority during procurement.  

Lower carbon concrete procurement and concrete zero 

The design stage embodied carbon calculations assumed a minimum of 35% GGBS would be utilised in each concrete mix design as a supplementary cementitious material (SCM), and this was reflected in the designer鈥檚 specification. Where feasible, the team were keen to further reduce the associated embodied carbon, partly driven by both 海角视频鈥檚 and Sir Robert McAlpine鈥檚 corporate commitments under ConcreteZero, and the University鈥檚 2030 net-zero commitment.

Sir Robert McAlpine鈥檚 commitments under ConcreteZero:

• 2025 (interim): Minimum of 30% by volume meeting the definition of 鈥榣ow embodied carbon concrete鈥� 鈥� less than or equal to the LCCG benchmark rating of 鈥楤鈥�
• 2030 (interim): Minimum of 50% by volume meeting definition of 鈥榣ow embodied carbon concrete鈥� 鈥� less than or equal to the LCCG benchmark rating of 鈥楤鈥�
• 2045: 100% of total concrete consumption meeting the definition of 鈥楴et Zero鈥� 

To further reduce emissions, Sir Robert McAlpine and 海角视频 collaboratively engaged with key supply chain partners, such as framework partner Heidelberg Materials and their nearby batching facilities. We also held collaborative workshops with 海角视频 and all relevant concrete using sub-contractors such as Bachy Soletanche, Toureen Group and Churngold. These sessions looked to reduce the embodied carbon intensity of the works whilst also managing the associated cost, programme and quality implications. The sessions typically focused on material efficiency, optimising the total cementitious content of each mix design and substituting Portland cement for GGBS, where feasible. 

All proposed concrete mixes were assessed against the Lower Carbon Concrete Group鈥檚 (LCCG) benchmark rating scheme. This scheme scores the emission intensity of a mix design against industry data, rating mixes from A (low carbon) to F (high carbon). The central banding of a 鈥楥鈥� rating is considered the UK average emission intensity. The project team was aiming to score as much 鈥楤鈥� rated (or better) concrete as possible, in line with ConcreteZero鈥檚 definition of 鈥榣ow embodied carbon concrete鈥�.

Key outcomes from the exercise included:

• 93.7% of the concrete poured (by volume) achieved the definition of 鈥榣ow embodied carbon concrete鈥� (B rated or better)
• 55.9% of the concrete poured (by volume) was 鈥楢鈥� rated 
• A comparative 2,254 tCO2e (A1-A3) was saved through low carbon procurement 鈥� relative to industry average emissions (‘C’ rated concrete) 鈥� a 25.7% tCO2e saving.
• Emissions reductions were predominately achieved through maximising GGBS proportions as a supplementary cementitious material 鈥� the GGBS was sourced relatively locally from Port Talbot.
• Individual mix designs included up to 85% GGBS 鈥� such as the mix used for the foundations of the site cabins (temporary works).
• Excess and waste concrete was utilised to create temporary site platforms 鈥� reducing the total amount of concrete ordered. 
• Over 35,000 m3 of concrete was poured onsite which accounted for 6,509t CO2e, all of which was assessed by Sir Robert McAlpine and monitored via their 鈥楾racker+ KPI鈥� system. An 鈥榓s-built鈥� embodied carbon assessment is also being prepared using the 鈥極ne Click LCA鈥� industry software. 
• The project was used as a 鈥榮ample project鈥� for Sir Robert McAlpine’s ConcreteZero submission requirements in both 2023 and 2024, in the process of informing the next revision of the LCCG benchmarks.

In conclusion, the results have highlighted the clear benefits of early collaboration with engaged supply chain partners who share our carbon reduction aspirations. This collaborative approach proved instrumental in achieving our goals. It showed that emission savings of approximately 25% are achievable at the procurement stage for ready-mix concrete. However, while these procurement stage savings were considerable, the greatest savings were realised through design stage optimisation. This underscores the importance of embedding low-carbon engineering principles in the design phase to maximise emission reductions.