TOKYO GAS TOP > Technical development > Interview with engineers > Engineers developing ENE-FARM for condominiums

ENE-FARM is a residential-use fuel cell system that can simultaneously produce electricity and hot water using city gas.
It was initially sold exclusively for installation in detached housing. In pursuit of wider diffusion, Tokyo Gas Co., Ltd., developed the world's first such system capable of installation in collective housing. An interview was conducted with personnel actually involved in the work, about the long road of development, which began even before the establishment of installation standards and culminated in the sales launch.

Profile of the developers

Yusuke Ito Residential Fuel Cell Marketing Section, Residential Fuel Cell Business Development Department
Mr. Ito's involvement in ENE-FARM development dates from 2006 and grew out of his experience of work in the assessment and adoption of residential-use products such as heat source equipment and hot-water terminals. Initially, he was assigned to the hot-water storage unit, but was later appointed to the position of project leader and then leader of the product technology team. He managed the joint development with Panasonic in aspects such as product specifications and the development schedule. He has since been transferred to the Residential Fuel Cell Marketing Section, and remains involved in work related to ENE-FARM adoption and planning.
Kosuke Kobayashi Residential Fuel Cell Development Section, Residential Fuel Cell Business Development Department
Mr. Kobayashi has been working in development of fuel cells ever since he joined Tokyo Gas. He majored in electrical engineering in his university days, and was initially assigned to the hot-water storage unit in development of ENE-FARM systems for condominiums. He currently serves as project leader, the post to which he was appointed in fiscal 2013, just before the sales launch.
Akira Sano Residential Fuel Cell Development Section, Residential Fuel Cell Business Development Department
Mr. Sano first belonged to the Facility Engineering Department after joining Tokyo Gas, and supported on-site product installation and marketing. His support for sales of ENE-FARM in fiscal 2012 occasioned his transfer to the Residential Fuel Cell Development Section in fiscal 2013. He now handles negotiations with manufacturers on items such as specifications related to installation and maintenance.

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Mechanism and principles behind ENE-FARM
ENE-FARM is a system that generates electricity by extracting hydrogen from city gas and inducing a chemical reaction with the oxygen in the air. It also enables use of the heat and water produced simultaneously in the generation process in the form of hot water.
Power generation principle

ENE-FARM system image
ENE-FARM for condominiums
ENE-FARM systems for condominiums were designed for installation in condominium pipe shafts or other such space. The performance and functions related to power generation and water-heating are the same as those in systems for detached dwellings. The condominium systems have higher levels of resistance to earthquakes and wind.
ENE-FARM for condominiums
Plane drawing of installation in pipe shafts
Example: diagram of installation in pipe shafts along an open corridor

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Toward wider diffusion of ENE-FARM, the residential-use fuel cell

Q: Please tell us about the course of the development of ENE-FARM for condominiums.
Tokyo Gas launched sales of ENE-FARM for detached dwellings in 2009. Subsequently, we developed the second-generation models in 2011. These had a fuel cell unit of tall and slim shape, enabling installation beside the hot-water storage unit. They were followed in 2013 by the sales launch of the third-generation models, which had a separate back-up heat source for the hot-water storage unit, for a three-unit composition. And in April 2014, we finally came out with the system for collective housing.
ENE-FARM history
2009 1st ENE-FARM Sales launch of the system for detached dwellings
2011 2nd ENE-FARM Development of the system with the fuel cell unit of tall and slim shape
2013 3rd ENE-FARM Development of the system composed of three units
2014 1st ENE-FARM for collective housing Sales launch of the first ENE-FARM system for collective housing

From the time we launched sales of the first-generation models, we had in mind the development of models for collective housing. This is because ENE-FARM diffusion required inclusion of collective housing in the market to induce a better mass-production effect. We began interviewing the in-house sales teams assigned to collective housing and major construction companies, and taking other steps in that direction a little at a time.

We started talking in earnest about development ideas for collective housing around 2011. At the time, we had just marketed the second-generation model and were considering approaches to the third. The three-unit makeup of the third-generation model was also selected in anticipation of the development for collective housing. From the start, we had taken the line of embarking on development for collective housing, which presented more technical difficulties, only after putting the technology for detached dwellings on solid footing.
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Unprecedented development beginning in the dark

Q: In what areas did you experience particular difficulties in development of ENE-FARM systems for collective housing?
First and foremost, there were no precedents, and we were in the dark about all sorts of things, including the shape and requirements for installation in pipe shafts. The studies of shape began with the production of wooden prototypes. We first tried out various shapes by putting sand that weighed the same as the fuel cells into a wooden box. The final shape emerged only after a process of repeated trial and error. For example, we tried making the unit narrower so it would fit more easily into pipe shafts. This showed us that an excessive depth would make it harder to perform maintenance.
Studies of shape using wood

The development term overlapped with that of the third-generation model for detached dwellings. We had to both nail down the details for commercialization of that model and pursue the development of the one for collective housing at the same time. It was a struggle day after day, and there were some unforeseen occurrences. But even under these circumstances, we managed to increase the degree of perfection embodied by the system for collective housing by timely reflection of all sorts of knowledge in the product specifications. I am referring to the diverse knowledge we acquired through our long record of achievements in the market and the insights obtained in the process of developing the system for detached dwellings, for example.

I find the work of verifying construction and maintenance engrossing. The task is to ascertain whether or not the construction and maintenance can be smoothly executed, through discussion bringing together all concerned in-house personnel, using a test model. Take the shape of the legs on the fuel cell unit, for example. The construction and maintenance people want the legs to be as long as possible, because this facilitates their work. The manufacturing side, however, wants them to be as short as possible, because long legs drive up costs (also in shipment) and make the unit look larger. So both the on-site workers and the manufacturers have a point. It is my job to find a realistic settlement acceptable to both. I am always caught in the middle, and have to stand in front of the equipment throughout the work of verification. That's why I feel completely bushed every time I complete one job (laughter).
Verification of installation in a pipe shaft

In such areas, one can sense the worth of having Tokyo Gas involved in the development instead of leaving it all to the manufacturers. I believe that ENE-FARM was perfected as a product precisely because of this approach of having professionals in each division, including production technology people like Mr. Sano, set forth their agenda and reflecting them in the development.
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Differences from the ENE-FARM system for detached dwellings

Q: What major changes from the ENE-FARM system for detached dwellings does that for collective housing represent?
To induce a better mass-production effect, we did not improve the basic equipment performance, but we did change everything that had to be changed for adaptation to the installation environment, in aspects including unit air-tightness, resistance to wind, and resistance to earthquakes. At the time, there were not even any installation standards, and we therefore began by asking the Japan Gas Appliances Inspection Association (JIA) to formulate standards especially for systems for collective housing.

Collective housing is generally in high-rise buildings, and the system consequently has higher levels of resistance to wind and earthquakes. We set the wind resistance at 30 meters per second for the collective housing system as compared to 15 for the detached dwelling system. We put air intake and exhaust apertures on the common wind pressure zone (on the same surface) so that the wind did not blow exclusively on one or the other. To prevent the diagnostic system from generating false alarms by the exertion of wind pressure on the unit interior, we also altered the shape of the interior components slightly. We confirmed that the type for installation on balconies could withstand a wind velocity up to 30 meters per second with attachment of a front cover designed to improve the appearance.
Installation inside pipe shafts

The resistance to earthquakes was heightened by making the legs of the fuel cell unit shorter. In order to facilitate construction and maintenance even with the shorter legs, we opted for a mount whose height could be adjusted, and had to start from scratch in respects such as deciding on the method of reinforcement and the thickness of bolts. Strength rises merely by making the bolts thicker, but there is a trade-off with the cost picture. We therefore held the bolt thickness down to a certain degree and compensated by making the panel stronger. In short, we had to consider a variety of facets.
Unit legs

We also made the overall system more compact and lowered the cost. Relative to the first-generation system, we greatly reduced the number of parts in the fuel cell unit. For the key components such as the fuel cell stack, we likewise reduced the amount of catalysts for smaller size and lower cost. Benefits were also brought by the reduction in the number of peripheral parts such as pipes and fans, and a revision of their arrangement. The number of parts is now only about half as high as in the first-generation system. The number was initially high due to the incorporation of parts that were only used in rare cases, in order to protect the core components. We found that some of these parts were not needed in the actual use of the products, and consequently reduced the number while improving the core components. One of Tokyo Gas's strengths that manufacturers lack is opportunities for contact with customers and acquisition of information from them. Our ability to get both customer feedback and operating data is a key advantage.

The size of the hot-water storage unit depends on the capacity of the tank. We set the capacity for the current unit at 147 liters as opposed to 200 liters in the first- and second-generation systems. The results of a simulation of use under actual conditions showed that there was no big difference between a capacity of 200 liters and one of 147, so we were able to reduce the capacity. To enhance the mass-production effect, we adopted the same backup heat source equipment as for the water heater, and the size is basically the same.
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Changing society through technology development

Q: Please tell us what you value as developers and give us your thoughts on ENE-FARM.
Ito"I value my belief in the excellence of the product."
When we began developing the ENE-FARM system for collective housing, there were not even any installation standards, and we had to feel our way along in the dark, as it were. This is why I was deeply moved when the product became a reality. As a developer, one thing I value is my belief in the products I am working on. I believe that ENE-FARM is a good product, and worked on its development with the idea of bringing it out into the world. I fervently hope for its widespread diffusion. Even when walking down the street, I end up looking to see whether or not the houses I pass by are installed with an ENE-FARM system (laughter). Unfortunately, it is still rare for me to spot one. As a developer, I intend to do my best so that the day will come when the systems will be a commonplace sight on my walks.
Formulation of technical standards

Kobayashi"Optimistic at base, and careful in each decision."
I like my work days, which bring a steady stream of things I don't understand. I believe that, whatever problems occur, they will eventually be solved. A way will be found somehow, and things will be ironed out in the end. While basing my attitude in this sort of optimism, I am very careful in my decisions on individual issues. As I see it, it is important for a developer to have both these traits. I also think it is vital for product development to involve various people. It is important to meet and talk with many people instead of trying to nail things down by mulling them over yourself. Good effects can also be obtained by getting away from the workplace for dinner or drinks with others.
I studied electricity in my college days, and conceived the desire to change the structure of energy worldwide. I had in mind a shift from the model of big power stations generating electricity in massive amounts far from the site of demand that it would supply after transport, to that of distributed power generation close to the sites of energy use. And today, this new age is on the verge of dawning. From now on, I hope to assist ENE-FARM's emergence as a core product that ranks alongside photo-voltaic power generation and other technology in studies of business in energy for homes.

Sano"Avoid excessive faith in your own entrenched ideas and view things from multiple perspectives."
In development, it is important not to put too much stock in what you believe as a matter of course. We are not engaged in basic research; we are trying to develop products that will be injected into the market for actual use. These products will come into contact with various parties, including manufacturers, contractors performing construction and maintenance, and customers. Developers must absolutely avoid making arbitrary decisions about them. In verification work, for example, even when we think that some feature will not cause any problems, we have to listen carefully to what others have to say and view the matter from various perspectives in our consideration of it. I might add that I believe ENE-FARM will come into the mainstream as a tool in the coming hydrogen society. Today, I go about my duties which the conviction that I am helping to lay the foundation for that society.

The developers of the fuel cell system ENE-FARM - creating a better future through ENE-FARM

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