Yanmar Announces Joint Development of Waste-Heat Boilers

September 30, 2011
Yanmar Energy System Co., Ltd.

 Yanmar announced the introduction of five new boiler models that utilize waste-heat warm water obtained from own-manufactured gas engine cogeneration systems with a capacity of 25, 35 and 50 KW (i.e. two 25kW units). Known as GENEBO*1, these new models were developed in collaboration with Tokyo Gas Co., Ltd, Osaka Gas Co., Ltd, Toho Gas Co., Ltd and Showa Manufacturing Co., Ltd.
  With a capacity ranging from 465 to 1,163kW, the boilers are utilized in tandem with Yanmar GENELIGHT cogeneration systems and will be commercialized in Japan under the name GENEBO SYSTEM as of October 1, 2011.
  Until now, GENEBO*2 could be used only with cogeneration systems of a lower capacity, from 5 to 9.9kW, but the improved models allow for application at larger facilities such as spas, fitness clubs or welfare institutions. Moreover, the improved models recover the latent heat from emissions, which increases energy efficiency from 90 to nearly100%.*3 In addition, the direct supply of pre-heated water and the proportional saving in combustion leads to annual reductions of 19%*4 in primary energy and of 25%*4 in carbon dioxide emissions, compared to gas boilers.
  Showa Manufacturing covered the design and production of the boilers, Yanmar Energy System the GENELIGHT cogeneration systems and the pipe connection to the boilers, while Osaka Gas and Tokyo Gas handled marketability and efficient integration of customer needs into product specifications. In regard to commercialization, Showa Manufacturing will produce and sell GENEBO, while Yanmar Energy System GENELIGHT.


1. Product Features:

1-1. Environment friendliness and economy
  By recycling the heat obtained when power is generated, GENELIGHT achieves superior energy efficiency, while GENEBO allows for optimum recovery of the waste heat from the cogeneration systems. When used for hot-water supply or heating, it utilizes a gas burner*5 which shortens the conventional operating time necessary, thus improving fuel efficiency and reducing expenses and environmental load.

1-2. Simple and compact design
  The previous GENELIGHT models required individual check, design and installation of heat exchangers when connecting the boiler to the cogeneration systems. However, the newly introduced boilers offer a simpler design and piping, permitting direct removal of warm water from the cogeneration systems through the attached pipes. In addition, as the heat exchanger and controlling unit are incorporated into the product, the space required for installation has been reduced by 20%*6, compared to previous models.

2. Model CP25VB3/ RECOS-S-J6500:

(Left) CP25VB3 GENELIGHT cogeneration system model with a rated output of 25kW
(Right) RECOS-S-J6500 GENEBO boiler model with a rated output of 756kW


  1. GENEBO is a registered trade mark of Tokyo Gas, Osaka Gas and Toho Gas.

  2. Available from October 13, 2009.

  3. Lower Heating Value (LHV): determined by subtracting the heat of vaporization of the water vapor from the higher heating value. This treats any H2O formed as a vapor. The energy required to vaporize the water therefore is not realized as heat.

  4. E.g.: When using the RECOS-S-4000 GENEBO model (->rated output: 465kW) with the CP25VB3 GENELIGHT model (->rated output: 25kW) at a fitness club of approx. 3,000 m2

  5. By utilizing an efficient combustion control method, the output of the gas burner is continuously adjusted, reducing loss from repeated on/off cycling.

  6. E.g.: When using the RECOS-S-4000 GENEBO model (->rated output: 465kW) with the CP25VB3 GENELIGHT model (->rated output: 25kW), the space required for installation can be reduced from 17 to 14m2.

3. Inquiries:

Public Relations Group,
General Affairs Dept., Yanmar Co., Ltd.