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Toyota, Aisin to Provide 20 Residential SOFC Cogeneration Systems for Test Program

Toyota Motor Corporation (TMC) and Aisin Seiki Co, Ltd will provide a total of 30 residential, solid-oxide fuel-cell (SOFC) cogeneration systems developed jointly by Osaka Gas Co., Ltd. (Osaka Gas), Kyocera Corporation (Kyocera), TMC and Aisin to five Japanese gas companies, as part of the New Energy and Industrial Technology Development Organization’s (NEDO’s) Solid Oxide Fuel Cell Verification Project for 2009.

The system is one-third lighter and smaller than TMC and Aisin’s 2008 system, facilitating easier installation in multi-unit housing complexes and detached houses. The power generating unit, which uses natural gas as its feedstock, delivers 700W of power with a rated generation efficiency of 45% (LHV) and 41% (HHV). Rated exhaust recovery efficiency is 40% (LHV) and 36% (HHV). (HHV includes the latent heat of vaporization of water.)

The hot water heating unit holds a volume of 70 liters (18.5 gallons) at approx. 70 °C (158 °F).

TMC and Aisin will provide four SOFC cogeneration systems to Tokyo Gas Co. Ltd., one to Toho Gas Co., Ltd., 23 to Osaka Gas and one to Saibu Gas Co., Ltd. TMC and Aisin have already supplied one to Hokkaido Gas Co., Ltd.

Once installation is complete in regular households, the five gas companies will gather data necessary for commercialization.

TMC and Aisin have worked together with Osaka Gas and Kyocera since March 2009 on the development of residential SOFC cogeneration systems. By joining in this verification project to gather data for the research and development of commercially viable systems, they hope to accelerate progress, culminating in the commercialization of residential SOFC cogeneration systems by the first half of the 2010s.



41% of the HHV is roughly twice what the Freewatt achieves.  It's better than many powerplants.  I would like to know how far this unit can be turned down; if it can be cranked down to perhaps 20% and the water vapor condensed for heat, a somewhat larger unit (2 kW) would be perfect as a domestic cogenerator for US homes.  Freewatt worries about producing power in excess of consumption, but it would be very easy to use electric heating elements as dump loads when average electric production exceeded domestic use.


It is very difficult to match variable power requirements (from less than 1 Kw to 24+ Kw) with a small domestic power generation unit.

A low cost energy storage unit (batteries, hot water, steam etc) plus a load leveling system would be required to handle-manage peak demands.

The total system cost could be prohibitive.

Nick Lyons

With net metering any excess power can just be sold back to the grid, a la photovoltaic installations in California. Considering the surge in natural gas supplies in US, domestic cogeneration looks like a good bet--probably more efficient usage of CH4 than fueling a centralized combined-cycle power plant, which itself is a big step up from a coal-fired plant.


Osaka Gas and Kyocera have been working on this for quite a while. Kyocera is a leader in ceramics for industry and is just the kind of partner that you want for this.

I think that you can run the 3-5 kWh units at 10% of maximum output. The efficiency goes down a bit, but as long as you keep them at operating temperature there should be no problem.


@HarveyD the peak loadings on a house are normally heating / cooling related which it is possible to substantially reduce with good building design.

Whilst the loadings on a single house can vary by that much, averaged out over many houses, the load profiles become much smoother.


3PS: you are right on.

However, morning showers (4.5 KW) + automatic heating thermostats (8+ KW) + coffee (1+ KW) + breakfast cooking (2 KW) etc add up, specially for the first 60 minutes or so in winter time.

With peak load management, hot water heater could be reduced or delayed for 1 + hour, house heating could be reduced at 50% capacity or less when coffee and breakfast cooking going on, etc. That is very doable but would cost more to install.


The point is to keep net consumption down close to zero, Harvey, not provide 100% of instantaneous demand.

This is the sort of thing that would work beautifully in conjunction with an EV or PHEV.  The fuel efficiency of the total system is much higher than the individual pieces in isolation so long as space heat/DHW is required.


So, what is the installed cost?

If this is too early to talk cost, it's too early to talk details
still, the point IS to keep net consumption down close to zero.

Meeting peak loads with a domestic FC is foolish.


E-P: The ideal would be zero energy consumption but as you know that is impossible in North of USA. The best next thing may be a very well built all-electric home equipped and controlled to use as little clean e-energy as possible.

We went from a large 5-bedrooms average built all-electric house (using an average of 65+ Kwh/day) to a much smaller 2-bedrooms, better insulated, south facing, all-electric, condonium, equipped with better appliances, SEER-25 heat pump, 3 LCD HDTV, programmable temperature controls etc using an average of 25 Kwh/day.

We could possibly do even better but we would have to reduce our hot water consumption, use a much smaller fridge, do away with the wine cooler, Use my 24-inch monitor as a TV, convince may wife to get use to 20C instead of 23C during the winter months, use the micro-wave instead of the large oven, change all windows and patio-doors for triple plate-glass units etc

Covering all 16 sq. M of window panes (all due south) with see-through high efficiency solar panels + 50 Kwh batteries + converters etc may make the place almost e-energy self-sufficient but could cost up to $80K (i.e. whenever the essential techonologies exist)

NB: The e-energy we already saved (about 40 KWh/day) could be enough for 4 small BEVs.


This is why smart meters help, if you know your electricity and natural gas usage on a daily basic, you can see what saves energy. Plug strips that can be turned off or an extra layer of window covering can show up immediately.

Multiply that time 100 million homes and even saving a bit can save a lot. We have lost our collective souls about doing our part to help ourselves AND everyone else. We need to get back to doing what is right for the country.

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