PV Case studies | Commercial

Cathedral Hill Industrial Estate - 500 kWp & 26 x Tesla Batteries (Jun '23)

Written by Spirit Energy | 15 Jan 2025

Credit - Cathedral Hill

Introduction

In a significant move towards sustainability and energy efficiency, Savills Investment Management embarked on an ambitious solar energy project with Spirit Energy on their industrial estate on Cathedral Hill in Guildford. Today, the estate is home to prominent tenants such as Halfords, Screwfix, and Topps Tiles, who benefit from the renewable energy solution provided. Over a two-year period, from 2021 to 2023, Spirit Energy successfully installed a comprehensive renewable energy solution across 13 newly refurbished units. The project combined 500 kWp of solar PV capacity with 351 kWh of battery storage, ensuring significant energy savings and carbon footprint reduction for future tenants.

Project Overview

  • System Size: 500 kWp Solar PV, 351 kWh Battery Storage
  • Location: Cathedral Hill Industrial Estate, Guildford
  • Main Components:
      • 1,250 x Trina 400W solar panels
      • Solis inverters (various capacities including 50 kW, 40 kW, 36 kW, and 25 kW)
      • 26 x Tesla Powerwall 2 battery units (2 per unit, totalling 27 kWh per unit)

System Design and Implementation

Working with Savills, Spirit Energy tailored the solar PV system to maximise energy generation and on-site usage. The solar panels were mounted on new trapezoidal metal roofs, ensuring a seamless and durable installation. To enhance the tenants' experience and provide transparency, remote display screens were installed in the entrances of each unit, showing real-time energy generation and usage data.

The battery storage solution comprised a total of 26 Tesla Powerwall 2 units, spread across the 13 units with each receiving 2 Powerwalls. This configuration provided each unit with 27 kWh of storage capacity, optimising self-consumption of solar energy and offering backup power during outages. By ensuring all units were equipped with robust battery storage, the project further increased the appeal of the estate to prospective tenants.

Estimated Performance and Benefits

  • Annual Energy Output: Approximately 450,000 kWh
  • Annual Carbon Savings: 232.54 tonnes of CO2
  • Projected Payback Period: 5 years
  • Estimated Annual Financial Benefit: £47,943

The solar PV system is expected to supply a significant portion of the estate’s energy needs, reducing reliance on grid electricity and offering tenants lower operating costs. With an 80% on-site usage assumption, the remaining 20% will be exported to the grid under the Smart Export Guarantee (SEG) scheme, providing an additional revenue stream.

Challenges and Solutions

One of the main challenges of the project was coordinating the installation across 13 different units, each with unique structural and electrical requirements. Spirit Energy conducted detailed site surveys and liaised closely with Savills and their construction partners to ensure a smooth installation process. Additionally, all necessary permissions from the distribution network operator (DNO) were secured, ensuring grid compliance.

Environmental Impact

Savills' installation at Cathedral Hill Industrial Estate represents a major step forward in reducing the estate’s environmental impact. Over the expected 25-year lifespan of the system, it is projected to offset over 5,800 tonnes of CO2, equivalent to planting approximately 34,000 trees. This aligns with the broader goals of reducing carbon emissions and promoting renewable energy adoption in commercial properties.

Tenant Experience

Feedback from incoming tenants has been overwhelmingly positive. The combination of lower energy costs, energy independence, and real-time monitoring has enhanced the value proposition of leasing units at Cathedral Hill. The inclusion of battery storage provides added resilience, a key selling point in today’s energy-conscious market.

Conclusion

The Cathedral Hill Industrial Estate project showcases Spirit Energy's capability in delivering large-scale commercial solar PV and battery storage solutions. By combining innovative design, high-quality components, and excellent project management, Spirit Energy has created a sustainable energy solution that delivers both financial and environmental benefits.

If you are interested in exploring how solar PV and battery storage can benefit your commercial property, contact commercial@spiritenergy.co.uk, or our Head of Commercial, Aidan Murphy - aidanm@spiritenergy.co.uk.


Aidan Murphy,
Head of Commercial