Honda has had a high level of environmental awareness since the founding of the company, and taken an aggressive approach to research and development in natural energy that is environmentally friendly because it does not rely on petroleum. In addition to developing a fuel cell electric vehicle and hydrogen supply system as a means towards achieving a hydrogen society and bio-ethanol technology, Honda has devoted considerable resources to solar power generation that converts the sun's energy into electricity. Honda took on the challenge of developing solar cells from the time that it first participated in the "World Solar Challenge", the pre-eminent solar car race. In 2002, it overcame the obstacles to the mass production of thin film compound solar cells. Most conventional solar cell modules used silicon, but Honda used a semiconductor compound made from Copper, Indium, Gallium and Selenide, known as CIGS, enabling electricity to be generated from a thin film measuring only 2 – 3 microns in thickness. In 2005, Honda formally announced the commercialization of CIGS thin film solar cells, continued with research and development after this, and started a new business selling solar power generation products for homes in October 2007 with its wholly owned subsidiary Honda Soltec.
As part of the renewal program for the Hanshin Koshien Stadium, Honda Soltec CIGS thin film solar cells have been installed on the roof over the infield seats called Ginsan (Silver Umbrella), and operation of the solar cells was started in March 2010. Yearly power generation is estimated to be approximately 193 thousand kWH*1. This is equivalent to the amount of electricity used to light up night games by the Hanshin Tigers at the stadium during the year.*2 This enables CO2 emissions to be reduced by approximately 133 tons*3 per year as compared to when electricity is generated with fossil fuel.
In place of silicon, Honda has developed CIGS solar sells that consist of a thin film to generate electricity made from Copper, Indium, Gallium and Selenide. This has reduced the thickness of the membrane from 80 microns with silicon to a mere 2 - 3 microns. This reduces the amount of energy consumed and CO2 emissions during the production process, making them environmentally friendly. The structure of these solar cells enables stable generation of electricity without a substantial drop in voltage even when a portion of the solar cell is in the shade.
Honda is striving to create a sustainable society that uses renewable energy. Electricity is generated with solar panels installed on the roof of the home, and this electricity is stored in household fuel cells. This will provide the power to run the home, as well as for fuel cell electric vehicles, motorcycles and the Monpal electric 4-wheel scooter. Honda will continue with its research into achieving a sustainable society based on electricity and hydrogen.