The RE based electrical generation system consists of 7 ducted wind turbines each rated at 90W, with integral photovoltaic aerofoils rated at 85 W each and a facade mounted PV system rated at 765W. This gives an installed RE based generation capacity of 1990W. The ducted wind turbines and photovoltaic systems are connected to a 48 volt battery bank via electronic charge controllers/regulators. The option favoured for this installation was an AC supply, powered from the battery storage system via a DC to AC power inverter. The battery unit has an auxiliary charging system connected to the local electricity supply in the event of insufficient power delivery from the RE systems. The electrical supply circuits in the gallery are powered from the renewable energy charged battery systems via an electronic 48V DC to 240V AC, sine wave power inverter. It is important to evaluate the options for maximising the efficiency of electrical supply and the resulting impact on power Quality. The benefits of this system are:

  minimised circuit and appliance costs are achieved as only one supply circuit type is required, operating at the standardised supply voltage (240V). This enables non specialised high efficiency electrical appliances to be used.

  supply of all electrical loads via DC/AC power conversion ensures complete segregation between the renewable supply systems and public electrical supplier. This prevents any distortion or interruption to the electrical supply network resulting from the direct connection of small renewable energy systems.

 since this supply option results in no physical connection between the renewable energy systems and the public electricity supply network, this eliminates the technical and policy complexities that exist for compliance with network connection.