Goole Farm

Goole Farm 250kW ground mounted solar

The 250kW solar PV system at a farm in Goole is not your average ground mount, nor was the cabling and grid requirements that posed an interesting challenge for the GMI installation team. In fact, the project is a fantastic example of how flexible solar PV systems can be when you are looking to maximise revenue from on site renewable energy generation.

Challenge 1 - survey of ground

Following planning approval for the ground mounted solar, the GMI Energy team conducted a detailed geotechnical survey of the site to check the stability and suitability of the ground for a post-driven solar PV system. Wind loading calculations were also undertaken in collaboration with the manufacturers.

Challenge 2 - design for a small area with shade

There was limited space available for the ground mounted system and potential risk of losses from shade from the farm building. In order to overcome this, our design team created an unusual ground mounted array that is approximately 6 metres high. The effect of shade from the farm building on a small area of the system was quarantined by ensuring that section was strung to an inverter with multiple MPP trackers. This segregates the losses from shade and prevents an overall loss in yield across the system.

Challenge 3 - grid connection upgrade and relocation

Before installation could commence it was necessary to upgrade the existing grid connection. This involved moving the grid supply and constructing a new supply building adjacent to the solar PV system. There were two additional advantages to this; the farm no longer had overhead 3-phase lines across the site entrance and we achieved further savings from reduced cable costs and losses from voltage drops along with reduced grid works for the upgrade.

Challenge 4 - installation to integrate an existing system

The first installation challenge was time; the farm already had an existing roof mounted solar PV system, which meant it was not eligible to pre-accredit the new install and secure the current Feed in Tariff rate so we were working towards the next FiT deadline.

The second major installation challenge was integrating the existing system, whilst retaining the separate metering system so that it did not affect the FiT rate of the old system. In this unusual scenario it was necessary to re-direct the feed from the existing system so that it could be incorporated into the G59 protection, whilst keeping the meters separate for FiT readings. At the same time, the electricity supply to the farm needed to be redirected from the new supply building. The result was a lot more cable but an effective set-up that ensured maximum revenue for the client.

 

The outcome

Mr Tindale now has a successful upgrade on his existing solar PV system that will generate additional revenue to the farm, with a healthy 13% ROI predicted from the new system. GMI Energy Facilities Management will now take over the monitoring and maintenance of the system, producing regular performance reports and undertaking annual inspection to ensure it continues to generate the expected yield.

Case Study - Goole Farm (pdf)