Complementing the commercial grid, the Honda Smart Home System provides heat and electricity for the home, and produces power for the use of electromotive mobility. Honda will also be exploring the system’s potential to independently produce electricity for the household in the event of a disaster.

Through the E-KIZUNA Project, Honda aims to reduce household CO₂ emissions to half of year 2000 levels by 2015.

Based on the E-KIZUNA Project agreement, Honda and the city of Saitama will collaborate on exploring the following items:

• Priority items for collaboration include creating the disaster-resistant city of the future with the help of a variety of energy supplies and electric mobility: enhancing access to electric vehicles and creating EV-related business models; creating independent home communities focused on local energy production and consumption; and developing household energy systems that can operate in the event of a disaster.

• Constructing an electric charging safety net. This includes identifying electric charging infrastructure appropriate for the unique characteristics of the city of Saitama, maintaining compatibility between current charging infrastructure and electric vehicles developed in the future, and using solar panels and fuel cells to supply energy.

• Stimulating demand and applying incentives, including promoting the shared use of electric scooters and automobiles, promoting the use of electric scooters for commercial use, and developing a wide variety of electric vehicles to meet citizens’ needs.

• Tailoring educational initiatives to local needs, including implementing riding safety seminars featuring electric scooters and implementing electric cart seminars for seniors.

Household cogeneration unit going on sale

Honda also announced it would begin sales this month of an all-new efficient household MCHP (micro combined heat and power) gas engine cogeneration unit through gas utilities across Japan. Building on its predecessors with a completely new design, MCHP1.0K2 serves as the core unit in the household cogeneration system ECOWILL, burning natural or liquid propane gas to generate electricity and heat water simultaneously.

Interior structure of MCHP1.0K2. Click to enlarge.

MCHP1.0K2 features Honda’s EXlink (Extended Expansion Linkage Engine). Comprising a trigonal link, swing rod and eccentric shaft, the new extended expansion linkage structure of the engine makes possible an extra-long expansion stroke (the piston stroke that produces power). By compressing a smaller volume of fuel and air and allowing the air-fuel mixture to combust and expand into a greater volume, an expansion ratio 1.4 times greater than the compression ratio is achieved, and a greater amount of combustion energy can be used to perform work.

Extended Expansion Linkage structure. Click to enlarge.

In addition, the shorter intake stroke helps reduce pumping loss, which is the energy lost from moving air into an engine’s cylinder during intake. Thanks to the higher expansion ratio, thermal efficiency is substantially higher than in an engine in which the expansion and compression ratios are equal. As a result, MCHP1.0K2 offers fuel consumption that is approximately 15% lower than that of the preceding model.

The shorter intake stroke of the high-expansion ratio engine helps make possible a smaller intake system and a more lightweight and compact overall design. The vertical engine layout featuring a vertical crankshaft, horizontal cylinder and integrated oil tank helps further minimize the weight and size of the unit. Due to the integration of parts and a variety of layout enhancements, MCHP1.0K2 has a 33% lower volume and weighs 11 kg less than the preceding model.

Extended Expansion Linkage structure working image. Click to enlarge.

An enhanced lower engine mount structure and other design enhancements help reduce pulsation and air channel noise in the intake and exhaust systems. The optimized placement of sound-proofing materials result in low vibration and noise equivalent to that of an air conditioner outdoor unit (43 dB(A)).

By integrating the heat exchanger with the catalytic converter and enhancing the cooling system design, a heat recovery rate of 65.7% has been attained. During combustion, exhaust heat and heat in the body of the unit is recovered at the high temperature of 75 °C, making possible the efficient production of hot water for bathing, heated floors and other uses.

MCHP1.0K2 offers ideal household electrical output of 1.0 kW, heat output of 2.5 kW and combined power and heat generation efficiency of 92.0%. Power generation efficiency is 26.3%, as compared to 22.5% for the preceding model.

In the alternator, the position of the rotor magnet and the position and number of the stator slots have been optimized to minimize eddy currents and prevent energy losses. The inverter features simplified circuits with highly integrated devices to reduce electrical resistance. When the electric output of the unit exceeds the electrical load usable by the household, the unit enters load optimization mode, using the excess electricity to generate additional heat.

In 2003, Honda began sales of its first compact household cogeneration unit, which combined a gas engine with Honda’s original sine wave inverter power generation technology. (Earlier post.) Under the brand name ECOWILL, cogeneration systems comprising the Honda cogeneration unit and a water heater utilizing exhaust heat have been sold by gas utilities across Japan and installed in some 108,000 households.