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Contributing to Expanding the Market for Ecocute Residential Heat Pumps

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Contributing to Expanding the Market for Ecocute Residential Heat Pumps March 2013 DENSO CORPORATION ・IEnergy Use Rationalization Technology Strategic Energy Conservation Development / Energy Use Rationalization Technology Actualization Development / Size-Reducing Development of a CO2 Heat Pump Hot-Water Supply System using Ejector Technology (FY2005-FY2007) Residential Heat Pumps ‒ Contributing to Expanding the Market for EcoCute Reduction of energy consumed domestically is one of the important issues in measures against global warming including CO2 reduction. In the supply of hot-water, accounting for approximately 30% of the energy consumed domestically, it is believed that installing a heat-pump method EcoCute unit has a great effect on energy conservation. EcoCute units, which have widely spread since 2005, have been aiming to reach a total number of 5.2 million units by 2010. However, an EcoCute equipped with a large volume hot-water storage tank requires a large space in which to be installed, and this had been an issue stalling popularization in urban areas. Fin of heat exchanger Towards promoting the popularization of heat pump hot-water supply systems, NEDO has implemented a project called“Energy Use Rationalization Technology Strategic Development”. Denso Corporation, who was the first to create a CO2 coolant heat pump powered EcoCute system, continued making efforts in reducing the size of CO2 heat pump hot-water supply systems by taking advantage of elemental technologies acquired through the development of such as heat exchangers for vehicles. After finishing the project, a space-saving EcoCute, integrating the hot-water storage tank into a single The installed heat exchanger, an important component that gathers heat within the air to create body with the heat pump unit developed as the hot-water. accumulated result of studies from the project, has been put on the market. Energy conservation and improvement of efficiency is realized by incorporating each of the elemental technologies onto existing models. Through OEM production for major hot-water supply system manufacturers, the system is being sold throughout Japan. EcoCute is also being sold by other household electronic appliance manufacturers, and as of August, 2011, total sales have exceeded 3 million units. DENSO CORPORATION 20 July 2013 Mazda Motor Corporation ・General Technological Development of Innovative Energy Conservation Next-generation Low-emission Vehicles (FY2004-2008) Clean Diesel Engine with the World’s Highest Level Fuel Efficiency and Environmental Performance Diesel engines are capable of efficiently converting burning energy into driving force and are superior to gasoline engines in the fuel efficiency performance. In Japan, hybrid vehicles are currently attracting attention for their high environmental performance including the performance relating to the exhaust gas, energy saving and CO2 emissions reductions. In Europe, however, diesel engine vehicles are very popular because of their high fuel efficiency performance. It is said that one out of every two vehicles in Europe is a diesel engine vehicle. On the other hand, traditional diesel engines emit larger amounts of air pollutants such as NOx (nitrogen oxides) and PM (particulate matters such as soot) than gasoline engines, The piston head part of“SKYACTIV-D” - the shape with the large dent and achieving environmental performance on par with that has made it possible to achieve high fuel efficiency and reduced pollutant emissions at the same time. of gasoline engines by purifying the exhaust gas has required the use of a catalyst that requires a large amount Conceptual diagram of the burning inside the engine of noble metal and large exhaust gas treatment equipment High compression ratio Low compression ratio such as urea SCR equipment. Against this background, NEDO conducted the“General Oxygen Technological Development for Innovative Next-generation Fuel particle Soot Low-emission Vehicles” Project for five years from FY2004 Uneven burning The burning efficiency is with the aim of improving the environmental performance of - The burning efficiency high because the degree of in the thick part is low. unevenness is lower. diesel engines to alleviate global warming and reduce the Burning the fuel after it has been uniformly mixed with air at a low emissions of environmental pollutants. Mazda Motor compression ratio improves the burning efficiency and reduces NOx and Corporation, which is the automobile manufacturer that has soot. been especially conscious of the possibilities of diesel engines among the Japanese automobile manufactures, participated in the project and endeavored to develop a new burning technology that does not compromise the high heat efficiency of diesel engines and to develop innovative catalyst technologies. As a result, Mazda Motor Corporation commercialized in 2012 the“SKYACTIV-D” diesel engine whose fuel efficiency is at the world’s highest level and whose exhaust gas is so clean that no NOx post-treatment equipment is required. This engine is being used in Mazda vehicles such as “ATENZA” and “CX-5,” and the number of SKYACTIV-D-equipped MAZDA vehicles sold (in Japan) by The high fuel efficiency-SKYACTIV-D engine with cleaner exhaust gas. This June 2013 exceeded 50,000, thereby greatly contributing to engine has an RPM range that is as wide as that of a gasoline engine. (photos courtesy of Mazda Motor Corporation) the popularization of diesel engine vehicles, which helps Mazda Motor Corporation reduce greenhouse gas emissions. 21 March 2013 JATCO Ltd. Energy Conservation ・Development of Material Surface Control Technology for Low Friction Loss High Efficiency Drive Machines (FY2002-FY2006) Improving Fuel Efficiency of a Belt CVT by Increasing the Coefficient of Friction With regard to transmission systems of vehicles, CVT (continuously variable transmissions) having driving performance and fuel efficiency superior to conventional staged AT (automatic transmissions) are gaining attention, and as the use of such leads to CO2 reduction, vehicle manufacturers throughout the world have been implementing them on various models. At JATCO LTD. boasting the world’s greatest share for CVT systems, increased fuel efficiency and improved environmental performance have been realized by numerous technological reforms since the 1990’s. However, with regard to“friction” which plays an important role in relaying torque, little was The pulley of a CVT. The coefficient of friction is improved by engraving detailed grooves. known about the mechanism of the phenomenon and it was difficult to be considered upon quantification. During such, NEDO implemented the project of “Development of Material Surface Control Technology for Low Friction Loss High Efficiency Drive Machines”, in which hydraulic equipment and turbine bearings were subject to the project as well as CVT systems. Cooperative studies were conducted by Jatco, Idemitsu Kosan, Kobe Steel, the Tokyo Institute of Technology, and Iwate University with regard to CVT systems, where a 20% improvement of the coefficient of friction between the element and the pulley was Pulley realized. This has been recognized as a remarkable academic result as well. Mechanism of a CVT (Image provided by JATCO Ltd) Subsequently, the elemental technology developed in this project was implemented in the newest “JatcoCVT8”, displaying further improved fuel efficiency and realizing high efficiency. This technology is used in two vehicle models being sold by a major vehicle manufacturer, and total shipments have exceeded 150,000 units. It is expected that models featuring this technology will continue to increase. JATCO Ltd. 22 December 2009 Mitsubishi Fuso Truck and Bus Corporation Energy Conservation ・R&D of Advanced Clean Energy Vehicles (ACE Project) (FY1997‒FY2003) Trucks and Buses Also Follow Hybrid Trends Eco-friendly vehicles that emit fewer greenhouse on the market in 2006 and the Aero Star Eco Hybrid gases and air pollutants are becoming more popular. large route bus was released in 2007. Both exceed As with passenger vehicles, the demand is also Japan’s 2015 fuel efficiency standards for heavy-duty increasing for commercial vehicles such as trucks and vehicles. As of March 2011, more than 1,000 Canter buses which operate on hybrid systems that integrate Eco Hybrid trucks had been sold. With orders now internal combustion engines and electric motors. coming in from Ireland and Australia, these hybrid About 20% of the CO2 emissions in Japan are vehicles are drawing worldwide attention. produced by the transporation sector. Of this percentage, freight vehicles are responsible for up to 35%. If commercial vehicles gradually switch to hybrid models, this will not only reduce CO2 emissions but also help reduce the potential effects of global warming. Hybrid vehicles store energy produced during deceleration̶energy that’s normally discarded in ordinary vehicles̶in storage batteries with the motor serving as the power generator. This energy is reused during acceleration. Not only does this reduce the burden on the engine, it also completely eliminates Engine room of Aero Star Eco Hybrid CO2 and air pollutants that are normally present in exhaust fumes. Through this project, Mitsubishi Fuso Truck and Bus Corporation has developed two hybrid systems: a parallel-type hybrid system for small trucks and a series-type hybrid system for large buses. The Canter Eco Hybrid light-duty truck was released Total engine exhaust (in liters) Conventional buses: Hybrid buses: Mitsubishi Fuso Truck and Bus Corporation Aero Star Eco Hybrid large route bus engine 23 December 2009, March
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