Case Study: 1–27 Henbane Court

Client: Crawley Homes | Principal Contractor: Mears | Location: Crawley, West Sussex

Project Brief

Crawley Borough Council is investing in its housing stock as part of a wider decarbonisation programme designed to improve living conditions for residents across Crawley Homes.

At Henbane Court, this project delivered a combined package of renewable energy and building fabric improvements, including:

• Solar PV & battery storage solutions
• Full replacement of the existing flat roof with a high-performance Bauder warm roof system, improving the thermal efficiency of top-floor flats
• Installation of A-rated windows (U-value 1.2)
• Cavity wall insulation.
• Achieving an EPC C rating for each flat
• New security & door entry systems
• Upgraded LED communal & Emergency lighting 

This integrated approach provides long-term energy efficiency gains while reducing potential fuel poverty for residents.

System Design

Henbane Court comprises two separate blocks:

1. Block 1–18: A three-storey building with a multi-level roofline split into three sections.

• System Size: 38 kWp PV array, three inverters, and two 3.3 kWh batteries
• Grid Connection: Two separate incoming mains located at opposite stairwell entrances
• Shading Mitigation: Panel optimisers installed on partially shaded modules

2. Block 19–27: A smaller block with shading from trees on the east elevation.

• System Size: 15 kWp PV array, one hybrid inverter, and 3.3 kWh battery storage
• Shading Mitigation: Optimisers to overcome tree shading

Forecast Generation: Combined annual output of approximately 59,000 kWh, delivering a potential yield of over £8,850 per year for the landlord.

Problem Solving

Project Involvement & Design Development

Blue Electric was invited by Crawley Borough Council to explore the potential of adding Solar PV to the newly replaced roof at Henbane Court. Our role was to design solutions that maximised available roof space while making full use of the existing access provisions already in place for the decarbonisation project.

We began with a G99 application to confirm the project’s deliverability and then developed battery storage options aligned with the requirements of PAS 63100:2024, ensuring compliance with the latest safety and performance standards.

A key part of our design development was to ensure the system would fully maintain the Bauder roof warranty, safeguarding the Council’s investment in the new warm roof system while integrating renewable technology.

Roof Loading & Design Revisions

Following scaffold erection, a structural survey identified potential loading concerns with the initial PV design due to joist spacing. The revised structural loadings significantly reduced the PV capacity unless an alternative solution was found.

We evaluated lighter mounting systems that would not penetrate the newly installed Bauder warm roof. After consulting with Bauder, we selected the BauderSOLAR F photovoltaic systems, which provided:

• Significant weight reduction compared to traditional ballasted systems.
• Single-manufacturer warranty covering both the roof and PV mounting.

This project also marked Blue Electric’s first Bauder installation, completed in collaboration with Bauder’s technical team. Successful delivery enabled us to achieve BauderSOLAR F Approved Installer status.

Inverter & Battery Location

A second design challenge was identifying an inverter and battery location that complied with MCS requirements, was easily serviceable, and avoided disruption for residents.

Our solution:

• External pre-manufactured cabinet (powder-coated and coloured green to blend into the surrounding landscape)
• Concrete base anchoring for stability and security
• Mechanical ventilation retrofit to ensure compliance with manufacturer guidance and prevent overheating
• Cabinet solution compliant with MIS 3012:2025, scalable across similar housing schemes, and particularly suitable for terraced properties with limited internal space

Sub-Contractor Collaboration

This project was delivered in partnership with multiple service providers, coordinated through a structured milestone programme to ensure works were completed in the correct sequence and without delay.

Blue Electric maintained continuous communication with all subcontractors, managing resources and deliveries while making live adjustments to accommodate weather conditions, material lead times, and workforce availability.

By fostering strong relationships with our supply chain partners, we created a supportive and collaborative working environment. This approach streamlined design integration and allowed multiple trades to work seamlessly alongside one another, ensuring high-quality junction and interface detailing across the project.

Resident Engagement

As the Solar PV systems installed at Henbane Court were not connected directly to individual resident properties, we tailored our resident engagement approach to provide clear communication and continued satisfaction throughout the project.

At the start of the works, Blue Electric delivered a block-wide introduction, outlining the project scope and providing residents with clear contact details for our project team. This gave every household a direct route to raise questions or concerns relating to the Solar PV works.

Building on our previous good practice in resident engagement, we also:

• Provided project information notices explaining timelines, work phases, and expected impacts
• Issued regular progress updates to keep residents informed of key milestones
• Maintained an open-door communication policy, with our site supervisors available to respond quickly to any queries

This proactive approach helped maintain resident confidence, reduced disruption, and ensured a positive experience for the community, even though the PV installations was not directly connecting to each residents home.

Apprentice Training

Blue Electric runs continuous apprenticeship programmes, employing at least one new apprentice each year. To maximise opportunities for hands-on learning in solar PV and battery system design, we invited four Mears Group electrical apprentices to spend a day each with our team at Henbane Court.

Each apprentice worked alongside different members of the Blue Electric team, providing one-to-one engagement and experience across all elements of the system installation.

In total, seven apprentices contributed to this project:

• Four visiting apprentices through our partnership with Mears
• Three of Blue Electric’s own apprentices, who supported the works throughout and continue to grow in confidence and technical skill

The experience gained at Henbane Court has directly enhanced our wider service capability, ensuring the next generation of engineers are trained in real-world, renewable energy projects.

Client Feedback

Crawley Borough Council praised Blue Electric’s:

• Proactive problem solving and collaborative working practices
• Clear communication with residents and stakeholders
• Ability to adapt system design to meet structural challenges without reducing system performance

The Council also highlighted Blue Electric’s innovative approach to meeting the latest MCS requirements for battery placement, noting the scalable external cabinet solution as an exemplar for similar housing schemes.

In addition, the Council commended our commitment to apprenticeships and investment in the future workforce of the electrical industry, recognising the value created by giving apprentices direct involvement in a live renewable energy project.

The project was successfully handed over on time, achieving the Council’s objectives of improved energy efficiency, reduced carbon emissions, and enhanced resident comfort.

Reference

Geoff Weekes.

Senior Supervisor, Mears, Geoff.Weekes@mearsgroup.co.uk

Jack Veaney.

Decarbonisation Manager, Crawley Homes, Jack.Veaney@crawley.gov.uk