3M contributes towards Owls Hatch Solar Farm meeting its tight energisation deadline

Owls Hatch Solar Farm is a landmark renewable energy project for the UK. The first and largest privately connected 132kV grid connection for a solar PV energy generator, Owls Hatch solar PV site is set across more than 213 acres in Herne Bay in Kent and its 49.99MWp farm of polycrystalline solar panels are capable of generating enough energy to power 11,900 homes per year (based on typical household energy consumption of 4170kWh/per annum). Essential to the success of the Owls Hatch solar farm project has been the installation of a private 132kV connection, which was designed and installed by Renewable Energy Connections, appointed by British Solar Renewables, working alongside the DNO, UK Power Networks.

One of the most impressive aspects of the whole project was the tight timescale, with the installation of a new substation and underground cable circuits taking just 11 weeks, from approval in January 2014 to energisation in late March, meeting the UK government’s deadline. However, that date was put at risk due to the unavailability of the 132kV High Voltage termination kits originally chosen.

Fortunately, Martin Parker, Sales and Marketing Director at Jointing Technologies – the firm supplying the electrical cables and accessories – came to the rescue with his suggestion to approach 3M. Says Martin, “We’ve known and worked with 3M for years, particularly in the medium voltage market and know that they have a policy of rapid turnaround of just a few weeks, largely because they hold stock locally. I was aware that 3M had also entered the high voltage market with cold-applied termination and jointing connections that enable installers to ‘mix and match’ with other vendors’ products. 3M products are ready to use and eliminate the need to create bespoke products or design them from scratch. We contacted 3M, it had exactly what we needed and the high voltage connection kits were delivered in just five weeks.”

The solar park 33kV network consists of four 33kV radial ‘strings’ with ring main units that supply individual transformers on the park. The 132kV cable itself weighs 15kg per metre, meaning that it can be difficult to work with, particularly when under pressure to meet fast-approaching deadlines. Says Lee Wootton, of Wootton and Wootton, the firm responsible for installing the cable sealing ends at Owls Hatch, “The 3M product is good to work with and has very simple instructions. Even though we hadn’t worked with the product before, it was relatively simple and fast to install. The composite insulator was a bonus, because it was lightweight enough to mean we didn’t need to introduce a hoist for the installation. Instead, the cable sealing ends can be installed by hand between two people. The 3M Cold Shrink Stress Cone was also simple to install, with minimal taping.”

Adds Louis Wright, Senior Technical Engineer, Renewable Energy Connections, “The 3M product was more than adequate for what was needed and most importantly, the rapid delivery by 3M meant that we could meet our deadline. We had confidence in the 3M product because we knew it had been type tested, with proven customer service and lead times. Towards the end of the project, many of us were on site all the time, including the 3M team, who were clearly committed to playing their part. Knowing that the cable circuit termination was being dealt with efficiently meant we could concentrate on other aspects of the project.”

Phase one of the Owls Hatch Solar Farm project went live on 29 March 2015. While the role played by the 3M Termination Kits may sound like a small detail, it prevented unnecessary delays to the project that could have had serious repercussions. The whole project underlines the fact that while product quality is important, the supply chain and support around it is essential in the energy industry.