Photovoltaic power generating systems for the Nagasakayama Tunnel

摘要

The global environment is threatened by global warming and many other environmental problems today. As a solution to these problems, effective utilization of natural energy is being promoted worldwide. Under such social circumstances, a photovoltaic (PV) power generation system was constructed for the Nagasakayama Tunnel to cut down the increase cost of electricity resulting from the expanded electric and telecommunications facilities for the Hanshin Expressway. This PV system with a rated power generating capacity of 50 kW began operation in October 1996. The operating records indicate that the PV system effectively reduces the peak power demand of the illumination system at the tunnel entrances by providing electrical energy as originally designed. The PV power generation system installed at the Nagasakayama Tunnel offers the following features. 1. PV-generated power is effectively utilized since the power generating pattern of the PV system and the load pattern of the tunnel entrance illumination system are similar. 2. Hybrid system (system interconnection) was adopted to ensure stable and reliable power generation. This system configuration eliminated the need for storage batteries for reduced costs. 3. Solar panels were installed near the tunnel entrances with design considerations for harmonious blending with the natural surroundings. Low-glare glass was used on the solar panels to minimize light reflection that may cause adverse effects to traffic safety. 4. A monitor terminal is installed in a parking area to make known the PV system in operation.