Hammerson and B&Q Partner on Eco Learning Store

20/04/2016

At Cyfarthfa Retail Park in Merthyr Tydfil, Hammerson and B&Q partnered to create an Eco Learning Store. It is one of the first projects in the UK to feature a Transpired Solar Collector system, which harvests the sun’s heat to warm the store’s interior, cutting energy bills and CO2 emissions. Other sustainability measures include rainwater harvesting, green roofs, low carbon materials and low energy lighting. The store presents a highly sustainable blueprint for retail parks and demonstrates the environmental and cost savings that can be achieved by owners and occupiers working together.

Lower operational costs

Reduced CO2 emissions

Energy Performance Certificate B rating

Property Week Sustainability Achievement Award 2015

Situation

B&Q, which operates 350 stores in the UK, is part of Kingfisher plc. Through its One Planet sustainability programme, B&Q has been cutting carbon, saving water, reducing waste and sourcing sustainable timber since 2007. Hammerson’s sustainability framework, Positive Places, aims to create retail destinations that deliver positive impacts economically, socially and environmentally.  

When B&Q approached Hammerson about an Eco Learning Store at Cyfarthfa Retail Park, Hammerson welcomed the opportunity to collaborate to build a large-scale, sustainable and low-energy store. Hammerson and B&Q agreed a set of best practice sustainability targets at an early stage of development. These targets go above and beyond local planning requirements and support Hammerson and B&Q’s sustainability objectives. Issues covered include energy efficiency, embodied carbon, recycled content, responsibly sourced timber, waste management, water consumption, biodiversity and climate change adaptation.

Fulfilling B&Q’s aspirations meant that the new store must:

  • Demonstrate a sustainable approach that is replicable and scalable
  • Be flexible and future proofed to respond to changing market needs
  • Be commercially viable
  • Be subject to a post-occupancy evaluation after 18 months.

The 4,200m2 Eco Learning Store, which opened in 2014, was designed by Powell Dobson Architects and built by BAM Construction. The store won the Property Week Sustainability Achievement Award in 2015, with Hammerson and B&Q praised by the judges for their collaborative and holistic approach.

Actions and benefits

Key sustainability features, being evaluated for potential roll out to other stores, include:

  • 34% reduction in gas consumption resulting from the Transpired Solar Collector system, which harvests the sun’s heat to warm the store, and solar thermal panels, which provide heat for domestic hot water.
  • 50% of available roof area covered with an ecologically diverse, plant rich green roof, supporting biodiversity, improving thermal insulation and reducing local flood risk by slowing rainwater run-off rates. The amount of green roof space was affected by factors such as weight, cost, access and equipment.
  • 50% of water provided through a rainwater harvesting system to flush toilets and urinals, and supply the garden centre irrigation system.
  • 23% less embodied carbon than industry benchmarks for similar retail developments (0.336 tCO2e per m2 ‘cradle to gate’ including transport), through the use of steel cladding rather than aluminium, insulation with recycled content and cement replacement in the structural concrete.
  • 15% better energy efficiency than required by Building Regulations (2010 Part L), with high thermal efficiency in the building fabric (air tightness of 2.47m3/hr/m2), energy efficient LED lighting, automatic daylight dimming and sun pipes that channel light from the roof through highly reflective pipes.
  • 100% of timber from guaranteed sustainable sources, as certified by the Forest Stewardship Council (FSC)
  • 90% of construction waste diverted from landfill.
  • Climate change adaptation measures included the green roof and Grasscrete in some areas of the car park, as part of a sustainable urban drainage scheme, slowing rainwater run-off and so reducing flood risk.
  • Locally procured materials to benefit the local economy and cut transport CO2 emissions, including steel from Port Talbot, cladding and roofing from Cardiff, insulation from Barry, and pulverised fuel ash concrete replacement sourced from Port Talbot and manufactured in Cardiff.

Financials

Commercial Transpired Solar Collector systems typically have a three- to ten-year payback, depending on whether:

  • The project is a new build or a refurbishment.
  • The system operates in series with or parallel to a conventional space heating system. If the system is in series, only the incremental cost of the collector and interfaces need to be accounted for in the payback.
  • Contractors increase rates for perceived risk associated with new technology.

For example, the 280m2 Transpired Solar Collector installed on the Eco Learning Store is expected to:

  • Produce direct gas savings of 37MWh per annum and other system benefits from recirculation and night cooling.
  • Deliver annual savings of circa £3,500, based on conventional system overall efficiency of 80%, average gas costs of £0.04 per kWh and including the Renewable Heat Incentive.
  • Cost £36,000, although this doesn’t account for the financial savings associated with the installation of a smaller heating system.
  • Estimated to achieve payback in less than 10 years.

The Transpired Solar Collector at Cyfarthfa Retail Park was an innovative demonstration project rather than a pure commercial solution. It attracted funding from the Welsh European Funding Office to inform future design and installation of similar systems in the UK on a commercial basis. Performance of the Transpired Solar Collector is being monitored by Cardiff University and Tata Steel.

Challenges & Achievements

 

PARTNERSHIP

 

How can owners and occupiers work together?

 

Owners need interest from occupiers to drive real changes. At Cyfarthfa Retail Park, B&Q set pioneering sustainability objectives for the project from the outset. As a result, B&Q and Hammerson took an unprecedented single client design approach, representing a breakthrough in owner and occupier collaboration. Rather than B&Q and Hammerson each engaging separate design teams, they worked together with a shared team.  

 

INNOVATION

 

How to introduce a new technology to the UK?

 

The Transpired Solar Collector was the result of a collaborative research project with the Welsh School of Architecture at Cardiff University, which aimed to determine the performance of the system and the contribution of renewable heat to the retail space. Black, perforated, steel roof-sheets absorb solar heat into a collector underneath, which imparts heat to the ventilation air that is then circulated mechanically throughout the building. Tata Steel supplied the Colorcoat Renew SC roof-sheets. There are two equally sized roof mounted solar collectors on the Eco Learning Store, totalling around 280m2. A comprehensive remote monitoring system was designed to capture performance data at one minute intervals. Early results show the Transpired Solar Collector system using over 20% of the available solar energy, offering a predicted payback of three years from gas savings.

 

BREEAM

 

Do BREEAM sustainability ratings work for greenfield sites?

 

It can be challenging for out-of-town, greenfield schemes to achieve the highest BREEAM ratings, even when the material choices, design and energy sources are all very sustainable. Greenfield developments tend to be less able to gain BREEAM ecology credits than those on brownfield sites or contaminated land. In addition, out-of-town schemes may not be able to gain as many transport credits as urban schemes. Whilst B&Q and Hammerson did not submit the Eco Learning Store for BREEAM certification, they ensured that the sustainability strategy for the store covered all BREEAM criteria, including aspects related to energy and water use, the internal environment (health and wellbeing), pollution, transport, materials, waste, ecology and management processes. As a result, the Eco Learning Store won the Property Week Sustainability Achievement Award 2015.

Find out more

Richard Quartermaine

Environmental Manager

 

http://sustainability.hammerson.com/

“We are delighted with the Eco Learning Store, which embodies the sustainability vision set by Hammerson and Kingfisher. I am gratified by how the team and industry collaborators rose to the challenge, overcoming many technical and financial barriers. We believe we have created a template for a truly sustainable store that is as replicable as it is ground breaking.”

Dr Antony Davies, Powell Dobson Architects