SYSTEM SPECIFICATION ❱ SD6 (300V) x 2 (12kW) ❱  SMA Mini-Grid Inverters ❱  Rectifier Protection Controller ❱  Battery Bank 720 AMPH ❱  10kVA 3 Cylinder Diesel Generator ❱  EWP Hot Water Diversion Control THE CHALLENGE A smallholding and business premises that is located in rural Yorkshire, England, is a great example of living off-grid. When the owners purchased and developed the property to become their new home and business premises, the property was not connected to the national grid. This was due to the rural location of the property which is in one of the highest points in the Yorkshire countryside. The owners originally enquired about connecting the property to the national grid, however, due to the excessive costs of obtaining a grid supply they quickly decided to seek an alternative. THE SOLUTION The location has a good wind resource, is well exposed and has plenty of space, so the obvious solution was to install a small scale wind turbine. In 1992, the owners installed their first wind turbine as part of a hybrid system with a diesel generator as back up. As the power demand of the property increased within the business and office premises, the system has been expanded to cover this demand and now has 2 x SD6 wind turbines, back up diesel generator and battery bank. When the battery is fully charged, any surplus energy produced from the wind turbines is diverted into hot water storage with a unique diversion control system. This ensures all of the renewable energy produced is utilised across the domestic premises, office and outbuildings. KEY COMPONENTS SYSTEM BENEFITS Turbines annual average output 21,500kWh Diesel annual average output 1,315kWh Annual energy used for hot water & heating 13,980kWh Annual energy used for electricity 8,835kWh Annual energy produced by the wind turbines 95% Annual energy produced by the diesel generator 5% LIVING OFF GRID COMPARISON ANNUAL RUNNING COSTS To power this application without the off-grid system would have an annual average cost of: £5,375.00 Annual running cost if powered solely on diesel £3,422.25** Annual running cost if electricity was purchased from grid *at 0.25p per kWh of energy produced by a diesel generator **at an electricity purchase rate of 0.15p per kWh WIND TURBINE CONTROLLER INVERTER HOT WATER DIVERSION BACK UP DIESEL GENERATOR GRID INVERTER BATTERY BANK 11 SYSTEM TYPE: Wind & Diesel Hybrid