TOKYO GAS TOP > Technical development > Low-carbon society > Development of the new model of a residential fuel cell, "ENE-FARM"

Development of the new model of a residential fuel cell, "ENE-FARM"

In 2009, Tokyo Gas succeeded in the first ever commercialization of a residential fuel cell cogeneration system (CGS), ENE-FARM.
The system has continued to be made cheaper and more compact since first going on sale to the general public in May 2009. The second and third generations went on sales in 2011 and 2013, respectively, and in April 2014, the world's first ENE-FARM fir apartments was also developed. The new, 4th generation model when on sale in 2015.

ENE-FARM is an energy system which utilizes a Polymer Electrolyte Fuel Cell(PEFC), highly efficient in extracting hot water and electricity from city gas, and offers high energy-efficiency and less CO2 emissions; a system suitable for low carbon societies of the future. In our efforts to expand its popularity, we will continue working on technological developments for next generation models which will offer further reductions in cost and required installation space, along with improved durability.



From our more than 30 years of experience in the research and development of various fuel cells, Tokyo Gas has acquired a high level of technological capability for producing fuel cell systems. In particular, our fuel processing technology to extract hydrogen from city gas, and our automatic operation control technology for the realization of maximum energy-saving are leading technologies in the world. By applying these technologies and our past accomplishments in the development of home-use gas appliances, we are working together with other manufacturers to jointly promote the development of our products.

As a large-scale national experimental project (from February 2005 to the end of FY2008), aiming to verify energy-savings and environmental friendliness of CO2 reductions when used at home, we installed 796 units of our home-use fuel cell systems as a field experiment. The better understanding of the technical challenges and insights into creating a more rounded product gained from the project all went into the design of ENE-FARM, the world’s first home-use fuel cell system, which went on public sale in May 2009. A cheaper, smaller second-generation model offering improved performance was then launched in April 2011, and installations in detached houses gained further traction with the appearance of a third-generation model in April 2013 that was even more compact and lower priced.
Total sales hit the 10,000 mark in April 2012, 40,000 by January 2015, and 50,000 units sold by August 2015. Tokyo Gas aims to have sold 300,000 by 2020.
In April 2015, the new, fourth generation model went on sale. This new model makes it easier for users to access electricity during power outages by incorporating a feature into the fuel cell unit which enables continuous power generation during power outages. This feature was only available as a separately installed extra for the third generation. Furthermore, the hot water storage unit is now available either as an integrated or detached part of the system, in order to more flexibly accommodate a variety of installation spaces. These four combinations of fuel cell and hot water storage units enable users to select the combination optimally suited to his or her needs and installation space.

For our next generation model, further cost reduction will be one of the most important issues to be addressed for more popularization as well as improvements based on the opinions of customers currently using ENE-FARM. We will continue to conduct our developments aiming our goals to achieve a low carbon society in the future by promoting gas appliances with higher energy efficiency, while continuing to respond to environmental changes in a timely manner.


To learn about its development stories⇒Development reports & Interviews with experts

The main specifications

The main specifications
  New model (on sale April 2015) 2013 model
(3rd generation)
Integrated Detached
Performance Power generation output 200W~700W 200W~700W 200W~750W
Electrical efficiency
39.0% /35.2% 39.0% /35.2% 39.0% /35.2%
Heat recovery efficiency
56.0% /50.6% 56.0% /50.6% 56.0% /50.6%
Overall efficiency 95.0%/85.8% 95.0%/85.8% 95.0%/85.8%
Tank capacity 140L 140L 147L
Dimensions Fuel cell unit H1,750mm × W400mm × D400mm H1,750mm × W400mm × D400mm H1,850mm × W400mm × D400mm
Hot water storage unit H1,750mm × W700mm × D400mm H1,750mm × W560mm × D400mm H1,850mm × W560mm × D400mm
Backup boiler (built into hot water storage unit)) H750mm × W480mm × D250mm※1 H750mm × W480mm × D250mm※1
Weight Fuel cell unit 77kg 77kg 90kg
Hot water storage unit 88kg 50kg 55kg
Backup boiler (built into hot water storage unit) 44kg※1 44kg※1
Installation space
(adjacent installation)
750mm(depth) 750mm(depth) 750mm(depth)
Approx. 1.7m2 (area) Approx. 2.0m2 (area) Approx. 2.0m2 (area)
Recommended retail price
(tax not included, separate installation fee)
Without feature for continuous power generation during power outages: 1,600,000 yen※1 1,900,000 yen
With feature for continuous power generation during power outages: 1,670,000 yen※1
Output during power outage (when feature for continuous power generation during power outages is included) Max. 500W  
 *1: Standard type

Integrated〕                     〔Detached

Page Top


Main features of new model

  1. Achieves cost reduction
This new product incorporates a more streamlined and compact design which reduces the number of parts used by 15% compared with the third generation system. When combined with a redesign of the fuel cell stack, which is the primary power generating device, and other changes, the suggested retail price for this new product has been brought down to 1,600,000 yen, a full 300,000 yen less than the third generation system. (This price does not include sales tax, the installation fee, the addition of the feature for continuous power generation during power outages, nor the addition of a backup boiler for the standard type system.) This is the first time in Japan that an ENE-FARM system is being offered for a suggested retail price of 1,600,000 yen.
  1. Incorporates feature for continuous power generation during power outages
In order to more easily enable users to utilize the ENE-FARM's generated power during even a power outage, a feature for continuous power generation during power outages has been built into the fuel cell unit of a new model added to the existing lineup. Such a feature was previously only available as a separately installed extra. Thanks to this feature, when a power outage strikes while the ENE-FARM is on and generating electricity, it will continue to supply power of 500W or less for up to four days (96 hours), and a special power outlet specifically for use during power outages allows this power to be supplied to electrical stands, televisions, mobile phone chargers and for other uses, as well as heating water and floor heating.

Continuous Power Generation During Power Outage
Continuous Power Generation During Power Outage. 
  1. Allows for more flexibility in installation thanks to a choice of hot water storage units
In order to allow for installation in a greater range of spaces than has previously been possible, two varieties of hot water storage unit have been developed. One variety is an integrated design, which is more compact thanks to its incorporation of a backup boiler within the hot water storage unit, and the other variety is a detached design, which allows for installation in a wider variety of spaces due to the fact that the backup boiler is installed in a physically separate space from the hot water storage unit. These options make it easier to install the ENE-FARM system in detached homes in the city or other dwelling where space is at a premium.
The hot water storage unit of the integrated model sticks out 80mm less than the second generation (integrated) system, due to the fact that a special backup boiler was designed and incorporated within the system. As a result, the new integrated model requires roughly 15% less space than the second generation (integrated) model and third generation (detached) model. In addition, both the new integrated and detached models are 100mm shorter than the third generation system, thus contributing to a more compact appearance.

Page Top