Bergey WindPower's BWC Excel-R/48: Peak power of 7.5kW. 48VDC output. Includes VCS-10/48 charge regulator and step-down transformer. Bergey wind turbines used in combination with a back-up diesel generator, and with optional photovoltaics (PV), provide a cost-effective and reliable alternative to conventional methods of electricity supply in remote areas. For home and village power applications Bergey technology includes advanced system architectures featuring state-of-the-art sine-wave, bi-modal DC-AC power inverters. For telecommunications and smaller village power applications, Bergey hybrid systems often incorporate photovoltaic subsystems to take advantage of the complimentary seasonal variations in wind and solar power. Bergey hybrid power systems are designed around a DC bus, which forms the common connection point for all of the DC sources and loads. A DC Power Center, which includes protective fuses, controls, and monitoring, forms the heart of the system. Wind turbines and PV arrays are connected to the DC Power Center through separate charge regulators. One or more battery strings are also connected to the DC Power Center to provide the short-term (typically 0.5 - 2 days) energy storage. The inverter system and any DC loads are also connected to the DC Power Center. The back-up diesel is connected to the inverter, which can double as a battery charger during diesel operation. Village power systems usually incorporate one or more 7.5 kW BWC EXCEL wind turbines. The turbines supply variable power to the DC bus, where it is converted to constant voltage, constant frequency AC power in the inverter, and used to supply the load. Any excess wind turbine power is stored in the batteries until they become fully charged. During short-term low wind periods this stored energy is available to supply the loads. If the battery voltage falls below a pre-set limit the back-up diesel is started and operated until the batteries again reach full charge. Battery charging from the diesel is provided by the bi-modal (DC-AC or AC-DC) inverter. In larger systems the inverter can also synchronize with the diesel generator to share peak loads. Diesel run time is kept to a minimum and the diesel is fully utilized when it is operated. Battery charging BWC EXCEL's can be supplied with outputs of 48, 120 or 240 VDC. They are well suited for large rural homes, remote villages and facilities, eco-tourism resorts, and larger telecommunications sites. The BWC EXCEL is most often installed on a guyed lattice tower, which is available in heights of 18 m (60 ft.) to 37 m (120 ft.). Tilt-up versions of these towers are available for sites without crane access. Non-guyed lattice type towers and monopoles (tapered tubular) towers are also available to heights of 37 m (120 ft). You may also supply your own tower if you follow BWC's technical requirements for Excel towers. Specifications Start-up Wind Speed: 3.4 m/s (7.5 mph) Cut-in Wind Speed: 3.1 m/s (7 mph) Rated Wind Speed: 13.8 m/s (31 mph) Rated Power: 7.5 kW for battery-charging Cut-Out Wind Speed: None Furling Wind Speed: 15.6 m/s (35 mph) Max. Design Wind Speed: 54 m/s (120 mph) Type: 3 Blade Upwind Rotor Diameter: 6.7 m (22 ft.) Blade Pitch Control: None, Fixed Pitch Overspeed Protection: AUTOFURL Gearbox: None, Direct Drive Temperature Range: -40 to +60 Deg. C (-40 to +140 Deg. F) Generator: Permanent Magnet Alternator Output Form: 3 Phase AC, Variable Frequency (Regulated 48 - 240 VDC after VCS-10).