Kendal Farm Benefits From Solar

Our Client runs a mixed farming business on the southern edge of the Lake District National Park with a beef suckler herd, 2 flocks of sheep comprising 1000 Lleyns and 130 Charollais, and 6 poultry units. The on site Lion Approved packing centre also packs eggs from other free range egg producers in the area.
Keen to reduce energy costs both now and in the future our client looked at the possibility of a wind turbine but were unable to obtain planning approval so invited agricultural solar PV specialists Westflight Ltd to look at the viability of a solar PV installation instead.
The poultry sheds are the largest users of electricity on the farm with more power being required during summer to run the ventilation fans within the sheds which was ideally suited to the output from a solar PV system. After a detailed analysis of the existing electricity consumption profile and discussions on possible future demands Westflight proposed a 150kW solar PV installation using 600 x 250Wp solar modules and 8 x SMA inverters. The location is close to an estuary and can experience high winds so the roof loading calculations and the design of the mounting system were critical to a successful installation.
Planning approval and a connection agreement with the DNO are precursors to the OFGEM accreditation process for systems over 50kW. Westflight acted as the client’s agent and navigated the project through this sometimes difficult phase to reach the OFGEM Preliminary Accreditation point where installation could commence.

Two South facing sheds 160 metres apart were used for the installation with 100kW (400 modules) and 5 SMA Tripower inverters on the first shed and 50kW (200 modules) with 3 SMA Tripower inverters on the second shed. Each inverter was then cabled back to the switch room and into the G59/2 relay. On long cable runs the sizing and selection of DC and AC cables is critical to correct system performance and is an area where costs are frequently overlooked or reduced by under sizing cables.
The poultry sheds are supported with an auto-start standby generator in case of grid supply failure.  The solar PV installation electrical design must integrate this correctly to ensure that the generator can start immediately if the grid fails whilst at the same time as the solar PV system is shutting down. The design of the G59/2 relay incorporated the RCD, MCB and surge protection, metering and the relay itself into one enclosure which made for a very neat and “clean” installation.
The Westflight team comprising 3 roofers, 1 electrician and the project manager arrived on site on Monday 22nd April.  The installation was completed and ready for commissioning 10 days later on the 2nd May. On the 8th May the G59/2 Witness test was successfully completed in the presence of the DNO engineer following which the installation went live. As part of the service package the system is continually monitored for both performance and faults through the SMA Sunny Portal and on the 25th May generated 1,128 kWh with a peak output of 128kW at around 3 o’clock in the afternoon and avoided over 3/4 ton of C02.
With around 70% of the generation being used on site and the remainder being sold through a Power Purchase Agreement our clients expect to achieve an early payback and an ROI of over 14%.