UK – G100 Export Limitation for Complex, HV Connected University Site

GridGEM enables DNO-compliant G100 solution for multiple installations on University site

Overview & Client Problem

Plymouth Marjon University, a large educational establishment based in south west UK, was awarded a large Salix financed fund to reduce their carbon footprint. Part of the solution was to install solar PV on the roofs. However, the site was given an export limit by the local DNO, Western Power Distribution (WPD), which required a G100 compliant export limitation solution that could also manage the energy flows in the context of a high voltage (HV) connected site.

In addition, the site’s solar PV systems were installed at locations that were a significant distance both from each other and the main incoming supply where import / export had to be measured.

As such, an “off the shelf” export limitation system would not meet the different challenges and so Argand Solutions were invited to supply a solution that overcame all of these challenges so that the system would meet the DNO’s stringent rules.

Argand’s Solution

The client site was HV connected and so Argand provided the client with a DNO-compliant metering solution to capture the real-time import/export at the HV connection point. This solution overcame many challenges that the electrical contractors were not able to solve. The metering solution provided the input to calculate the dynamic set-point for the solar inverters.

In relation to the generation inverters, the client’s solar PV providers, Mole Energy & Naked Solar, both utilised Solar Edge inverters for the generation conversion from DC to AC. Argand Solutions provided a dynamic export management solution that interfaced directly with each inverter over LAN and provided a dynamic set-point for each inverter to ensure the system maintained the optimum output to meet the DNO’s export limit and ensure that the client received the maximum possible generation.

Client Benefits

A significant fund would not have been able to be used if Argand had not been able to solve the problems at the site to make the system DNO-compliant. This involved solving the HV metering issues, the distance issues and the optimal interface with the chosen inverters.

In addition, the client can receive real-time data from the Argand site to continuously monitor the output.