Eaton’s Electrical Sector has supplied and installed complete BoS (balance of system) solutions for three major new solar energy parks (developed and owned by Lightsource Renewable Energy).
The largest of the new parks, at Chittering in Cambridgeshire, has an installed capacity of 5MWp. The other two parks, at Great Knowle Farm and Eastacombe Farm in Devon, have capacities of 2.5MWp and 3.5MWp respectively.
On all three of the projects, Eaton worked in close conjunction with engineering and project management teams from supplier of solar photovoltaic (PV) systems, Solarcentury.
For each of the new solar energy farms, Eaton designed, supplied and installed the custom built electricity substations that provide the vital link between the photovoltaic panels and the national power distribution grid. At the Chittering and Eastacombe sites, three substations were installed while, for the smaller system at Great Knowle, only two substations were needed. In all cases, Eaton constructed and tested the substations on-site in order to minimise the time and cost of installation and commissioning.
Each of the substations is equipped with Eaton DC junction boxes to provide safe and secure connections for the incoming supplies from the PV panels, and multiple SolarMax TS-SV 330kW inverters, which achieve maximum power point (MPP) efficiencies of 99%. The low voltage AC supplies from the inverters feed Eaton Memform low voltage switchboards rated at 3,200A, which offer Form 4 separation and the high fault current capacity needed to ensure safe operation in these demanding applications.
The substations also incorporate 280V to 11kV transformers and Eaton Xiria 11kV ring main units with integral G59 protection. These versatile units use reliable vacuum switching technology to minimise both maintenance requirements and the environmental impact of the equipment during manufacture and at end of life disposal.
At the Eastacombe site, the connection to the grid is at 33kV and, to cater for this, Eaton supplied an additional 11kV to 33kV transformer, together with the necessary third party 33kV switchgear.
Very tight time schedules were in place for all three of the projects, with the aim of ensuring that they were completed before the next stage of the Feed-in-Tariff (FiT) degression took effect. In spite of these very tight deadlines, Eaton ensured all of its equipment was in place and fully operational by the times dictated in the project schedule.