When your local electricity company wants to charge GBP 35 000 (over USD 52 000) to lay on mains power you know alternative sources have to be investigated.

This was certainly the case for the owner of a refurbished shepherd's house in the idyllic setting of Mindrum Farm in the North of England. A PV-diesel hybrid system now provides an economically and environmentally sound solution to the farm's various power requirements.

The occupier needed a secure power supply with scope for future expansion. The system not only had to meet the demands of typical domestic appliances, but also needed to match occasional surges related to various agricultural activities on the farm. The turnkey package supplied by Solar Century comprises a ground-mounted 2,1 kWp PV array charging a 450 Ah battery via a charge controller. This feeds power to the main consumer unit via a modified sine-wave inverter with a maximum output of 4,5 kVA. A water-cooled diesel generator feeds power to a subsidiary consumer unit to meet occasional and high power loads and for supplementary battery charging. The diesel set is activated when any of the loads on the subsidiary unit are used, or if the battery is discharged below a pre-set level. The costs of all the goods and services for the installation of the PV hybrid system amounted to GBP 17 500 (USD 26 000), in other words only half of the cost of connecting to the mains. Information Dan Davies, Solar Century Fax: +44 (0)870 735 8101 [ Top ] [ Previous article in PV Power ] [ Next article in PV Power ]

Programme summary • Location: Coldstream, Northumberland, UK • System: Isolated PV/diesel/battery hybrid • Power: 2,1 kWp ground-mounted array, 11 kVA backup Lister Petter diesel generator • Modules: 28 x Astropower AP7105 monocrystalline modules • Storage: 450 Ah battery at 48 V • Inverter: Trace SW4548E 4,5 kVA modified sinewave inverter • Typically daily consumption: 8 kWh • Information: Dan Davies, Solar Century, Fax: +44 (0)870 735 8101