Hybrid DC-AC homes with roof top solar power

¹ Department of Mechanical Engineering, BMS Institute of Technology and Management, Bengaluru, India
² Department of Mechanical Engineering, Ramaiah Institute of Technology, Bengaluru, India
³ U R Rao Satellite Centre, Bengaluru, India

Abstract

The paper investigates the feasibility of a hybrid DC-AC home with roof top solar power. In recent times, roof top solar power has become popular for residential homes. Generally, the power obtained from roof-top solar panels is converted to AC with a power control unit and routed to the existing wiring network of the houses designed essentially to support the Electric Utilities which deliver AC power. Solar power with DC bus routing power to various sub-units and Brushless DC (BLDC) motor-based systems have been successfully flown in satellites for decades. The study presents the possibility of having a dedicated DC bus (24V / 48V) in the home connected directly to roof-top solar panels along with the traditional wiring network to support AC power (220-230V) from Electric Utilities. The recent success of the BLDC based home appliances further highlights the potential. This will also help to benefit from higher efficiency due to BLDC and avoid the conversion losses as home appliances that can run on DC power are presently available. It is now possible to have an independent local Roof Top solar power-based DC home-grid to support lighting circuit and homeappliances that operate on DC power. The existing wiring network for AC can continue to support high power equipment like motors, boilers, washing machines etc., It will also simplify the power control unit as the traditional inverter portion is avoided. Thus, the proposed hybrid DC-AC home needs be viewed in terms of an overall green approach which will be a paradigm shift for energy efficiency and lower carbon footprint. It has the potential to boost the sale of DC home appliances.