Ashfield District Council – Northern Transport Depot

Drivers for the project

The Clients requirements were to install a Solar PV system on to the roof space at the Northern Depot to reduce their Carbon Emissions and help save on energy costs.


Custom Solar were contracted under a JCT Minor works contract to deliver a turnkey solution for the installation of solar systems Ashfield Northern Depot 49.95kWp.


As part of the initial design phase our design engineering team reviewed the clients half hourly electrical data in order to size the solar system appropriately. A number of options were presented to the client based on current and future electrical consumption usage on site. A 49.95 kWp system was chosen, comprising of 185 No. 270Wp panels and 2 No. ABB inverters. Suitable isolators, a new dedicated PV distribution board and generation meter were installed and fitted seamlessly into the sites existing electrical network.

The system will produce enough electricity (42,358 kWh per annum) to power around 11 residential homes per year or power 19 electric cars. After 25 years in operation the project is predicted to have saved 84.9 tonnes of CO2e, an equivalent of 439,159 fossil fuelled car miles, 56 fossil fuelled cars off the road and 339 pine trees planted.


Due to roofing issues on parts of various buildings we were tasked to work on an area that had recently had a roof replacement, this meant we had design the system in such a way to distribute the weight across the trusses of the building.

Multiple systems were appraised but ultimately the final system was designed around the utilisation of 2 x ABB inverters to maximise efficiency of the system. Due to areas outlined in the structural survey report, the module layouts were designed to allow for spacing between each row to evenly distribute the weight load and match the structure of the building.

Access within the site had to be tightly controller as the yard around was extremely high in traffic and footfall, with a pedestrian walkway directly under the front of the building.


The project was delivered in one week including the provision of a monitoring solution which allows both Ashfield District Council and Custom Solar Ltd to live monitor the performance of the system remotely. Custom Solar provide monthly reporting and annual service check on the system to ensure optimum performance.

This project demonstrates again Custom Solar’s ability to work on busy operational sites , this site was particularly complex given it was the main transport depot for the council and so moving vehicles had to considered at all times. We had to be innovative with our designs in order to work around the structural issues with the roof which shows how we work with clients to deliver suitable and fit for purpose projects ensuring all options are considered before a projects is progressed or deemed unsuitable.

Project details

System size
49.95 KWP
Panel Manufacturer
Number of panels
Inverter Manufacturer
Estimated System Annual Performance
42,358 KWH
Completion date
July 2017
Ashfield District Council – Northern Transport Depot website