The Sanyo Group is promoting the development of its own environmental technologies, including environmental purification and energy technologies. The R&D departments consider the level of environmental impact reduction as one of the selection standards for new R&D projects, and perform advance quantitative evaluation of expected environmental benefits for each R&D project based on internal standards. Sanyo also establishes annual targets for the number of basic research projects involving environmental technologies that are ready for transition to the application research and product development stages. By performing regular verification to ensure that selected R&D projects produce steady results within a planned development period, Sanyo is realizing rapid development of environmental technologies.

HIT solar module HIP-200BK5

The Heterojunction with Intrinsic Thin-layer (HIT) solar cell is an original technology developed by Sanyo, and has a structure that combines a crystalline silicon substrate and an amorphous silicon thin film. In the practical size, it offers the world’s highest energy conversion efficiency of 23%, on a research level. Through progressive application of this technology, Sanyo is now providing mass-produced solar panels with the world’s No. 1^*1 electrical generation capacity per unit of installation area.
Sanyo Electric opened the Advanced Photovoltaics Development Center at its Gifu site in April 2008. The company has now established a structure to develop thin-film solar cells requiring only one percent of the silicon needed for the currently available crystalline solar cells. Since thin-film solar cells use less silicon, they contribute towards effective use of resources, and cost savings through the reduction of raw material. Moreover, these cells require less energy in manufacturing. Sanyo will continue to focus its management resources and enhance the development of even more advanced technologies.

*1 According to a Sanyo survey. As of May 1, 2009, Sanyo’s mass-produced solar power generation system for household use has a cell energy conversion efficiency of 19.7%.

• Click here for more information on Sanyo’s HIT solar cells
  and solar power generation systems for household use

■Changes in conversion efficiency of Sanyo's solar cells

■Changes in Sanyo's solar cell production capacity

HIT solar cell construction

Sanyo’s HIT solar cell features a unique construction that combines technologies for crystalline silicon solar cell and thin film silicon solar cell. It offers a radical improvement in energy conversion efficiency, by inserting to a degree of 10 nm a non-doped intrinsic thin a-Si:H layer (i-type a-Si:H) between crystalline silicon (c-Si) and amorphous silicon (a-Si:H) doped on a p type and n type. The following are the main features of HIT solar cells.

1. Achieved the world’s highest energy conversion efficiency in the practical size, as a silicon type solar cell.
   (In May 2009, announced the world’s highest energy conversion efficiency of 23% in a 10 cm x 10 cm size.)

2. Offers both a thinner silicon wafer and improved energy conversion efficiency.
   (Achieved the world’s highest conversion efficiency of 21.4% for a practical size silicon solar cell with a thickness of 100μm or less, using a wafer thickness of 85μm.)

3. Net annual power generation is great, due to a minimal decrease in summer output caused by higher temperatures (only half the decrease compared to a regular silicon solar cell).
4. World’s No. 1 power generation per unit of installation area, on a mass production level.
   (As of May 2009, according to a Sanyo survey; based on a solar power generation system for household use.)
5. Sanyo’s bifacial incident light type HIT Double solar panel offers the world’s highest level of electrical generation performance, for light hitting either the front or back of the solar cell.

Lithium-ion battery system for HEV (under development)

Sanyo has been mass producing and supplying nickel-metal hydride batteries for hybrid electric vehicles (HEVs) to automakers such as the Ford Motor Company and Honda Motor Co., Ltd. The company has also been jointly developing next-generation nickel metal-hydride battery systems together with Volkswagen. Sanyo is responding to increasing demand for HEV rechargeable batteries by realizing optimal systems based its battery technology developed in various consumer product fields, and demonstrating its strength in technology for mass production with consistent quality.
In order to supply HEV lithium-ion batteries with a high level of safety and performance, Sanyo is now promoting the development of smaller, lighter, and lower cost batteries while improving the technology performance (safety, output, durability, and temperature resistance) necessary for lithium-ion batteries. In the area of safety, the company is promoting R&D into optimal cell structures and battery materials for overcoming the severe conditions associated with vehicle installation, such as over-charging, heat, and impacts.

• New plant under construction to increase production of HEV lithium-ion batteries. Click here for details.

HFC refrigerants are gases that contribute greatly to global warming. In order to replace these materials in heating and cooling equipment, it has become necessary to develop natural refrigerants with low environmental impact. Since CO₂ is a gas occurring naturally in the atmosphere, Sanyo has been working on developing CO₂ compressors since 1998.

Since the natural refrigerant CO₂ requires an operating pressure that is 4 to 10 times greater than that of HFC refrigerant, it was necessary to develop a CO₂ compressor that is pressure resistant, has reliable sliding parts, is highly efficient, and lightweight. Faced with this challenge, Sanyo succeeded in developing the world’s first CO₂ rotary 2-stage compressor, which pressurizes the CO₂ in two stages, from low to intermediate pressure, and then from intermediate to high pressure. This was done by using the shell interior to contain the intermediate pressure gas. The new design is a departure from the conventional single-stage compression, which raises pressure from low to high pressure all at once. As a result of this unique technology, the thickness of the compressor shell was reduced down to 65%, thereby halving the weight of the compressor, and realizing a radically more compact size.
Sanyo’s CO₂ compressor is now being used in numerous products worldwide including heaters and water heaters, as well as in commercial refrigerators, freezers, and vending machines. This is thanks to its features of low power consumption resulting from the highly efficient two-stage compression technology, and the major benefits CO₂ refrigerant, which has a global warming potential (GWP) of 1.0 compared to conventional HFC refrigerants, which have GWPs of 140 to 11,700. By applying this technology to various heating and cooling equipment, Sanyo will continue to help fight global warming through its products.

CO₂ Rotary 2-stage compressor

Featuers of CO₂ Rotary 2-stage compressor

Sanyo’s electrolyzed water technology offers outstanding purification benefits, by performing powerful elimination of bacteria, suppression of viruses, and breakdown of organic substances. It does this through the creation of electrolyzed water that contains OH radicals and hypochlorous acid, based on the electrolyzation of tap water using chlorine-generating electrodes. Sanyo’s unique electrolyzed water technology developed over many years has been applied to water and air purification, and the company has applied it to various products including the Aqua Clean System and the virus washer series.

As the next step in this electrolyzed water technology, Sanyo has now developed a unique electrolytic ozone-generating electrode, which contains a mixture of platinum (Pt) and tantalum oxide (TaOx), an insulating material. The electrolytic ozone-generating electrode is able to easily produce electrolyzed water containing activated substances with oxidizing power such as OH radicals and ozone, while also offering low power consumption^*2, with an electrode that does not contain environmentally harmful substances such as lead. This enables the creation of compact energy-saving electrolytic units. Moreover, since the new electrode can use a wide range of water qualities even in regions where chloride ions are scarce in the water supply, a large variety of applications can be expected, from commercial to consumer products.

*2. Since this technology can create ozone using lower current density compared with a platinum electrode, the necessary power source is smaller, thereby producing less heat and saving energy. As of March 27, 2009, it offers the industry’s lowest power consumption as an electrolytic ozone-generating electrode that does not contain any environmentally hazardous substances.

• Aqua Clean System
• virus washer series

Electrolytic ozone-generating electrode

Photo of electrode cross-section

Eco-Store System

The “Eco-Store System” is an in-store integrated management system for supermarkets. It offers control for optimum energy savings through a master controller providing uniform energy management for in-store showcases, including refrigeration units for both frozen and chilled food showcases, and in-store air conditioning systems. Previously, these various systems and devices were operated through individual control systems, but by connecting each device to a communications network and by monitoring real-time operation conditions, the Eco-Store System is able to maintain optimum device operation, thereby ensuring food freshness while saving energy. As a result, supermarkets can achieve annual electrical savings for their refrigeration equipment of up to 23%.
As of October 2008, approximately 300 stores across Japan have installed the Eco-Store System. On average, the expected reduction in annual CO₂ emissions for one store is approximately 60 tons, and based on that average, an annual reduction of CO₂ emissions for the currently installed systems is approximately 18,000 tons.