In the residential sector, we are developing and encouraging wider use of gas stoves fitted with highly energy-efficient burners, high-efficiency latent heat recovery gas water heaters, and home generators that utilize waste heat at the same time as they generate electricity.
Whereas conventional residential gas water heaters have a maximum heating efficiency of 80%*,*high-efficiency Eco-JOES home water heaters come equipped with an exhaust heat and latent heat recovery system that boosts this figure to 95%.* Assisted by the industry-wide “Eco-JOES Adoption Campaign” to promote the adoption of Eco-JOES, the number of home installations is rising by the year. As of the end of fiscal 2016, the number shipped by the industry as a whole had reached some 7,240,000. Our estimates show that these units produce 13% lower CO2 emissions than conventional models. We are also adding EneLook functionality to our water heater remote controls to display how much gas and hot water is being used, helping our customers to save water and energy.* Calculated on higher heating value (HHV) basis.
In a world first, the ENE-FARM residential fuel-cell cogeneration system designed for use in detached dwellings went on general sale in May 2009. ENE-FARMs can cut CO2 emissions by about 1.3 tons per year compared with conventional systems producing an equivalent amount of electricity (0.7 kWh) and heat (1.01 kWh). They are expected to play a key role in taking the fight against climate change into the home.
The ENE-FARM lineup for detached dwellings underwent facelifts in 2011, 2013, and 2015, and a new fifth generation of models offering enhanced resilience functionality for emergencies was released in April 2017. The new resilience model*1 with built-in self-sustaining power generation capability is capable of continuously generating electricity in a power outage for up to about eight days (up from the four days or so achieved by previous models), and can be started up even during a grid outage using a commercially available storage battery or generator*2 as an AC 100 V power source. The new models can be connected to the Internet to make them part of the Internet of Things. With the launch of our new network connection service in August 2017, it is now possible for users to switch baths, floor heating, and power generation systems on and off and to check energy usage when they are away from home by using a smartphone app. In a world first, an ENE-FARM model designed specifically for use in condominium buildings was also launched in April 2014. Due to the more restrictive installation conditions found in condominiums than in detached homes, this model's main unit was made more airtight, allowing it to be installed in the pipe shafts of open hallways in condominium buildings. So that it could be installed on higher floors as well, it was made more earthquake resistant by strengthening the legs used to anchor the unit, and the supply and exhaust structure was modified to improve wind resistance and allow operation in strong winds. In July 2016, the ENE-FARM lineup for condominium buildings was expanded by the addition of new models offering added functionality such as built-in self-sustaining power generation capability. As of the end of March 2017, total sales had reached approximately 79,500 units.
*1 Like existing products, the fuel cell unit comes in two models: a resilience model that offers built-in self-sustaining power generation capability, and an ordinary model without this capability.
*2 ENE-FARMs are not guaranteed to be capable of being started up by all commercially available storage batteries and generators. For startup, a power supply must meet certain conditions. These include: AC 101 V ± 6 V, at least 1 kW of power, and at least 500 Wh of capacity.
"ENE-FARM" residential fuel cell cogeneration system
(Assumptions for estimates)(1) CO2 emission factor: 0.65 kg-CO2/kWh for electricity (average factor for thermal power in FY2013 according to the Plan for Global Warming Countermeasures (May 2016)), 2.29 kg-CO2/m3 for gas (Tokyo Gas data)
■Active utilization of solar energy
Tokyo Gas offers two solutions that combine use of gas and renewables: Dual Power Generation, which combines photovoltaic power generation with an ENE-FARM home generator, and SOLAMO, which combines solar heating with an Eco-JOES high-efficiency water heater. Both of these solutions provide the backup systems needed when actively utilizing solar energy, which is subject to fluctuations in output, and they can make a major contribution to reducing households' environmental footprints.
Schematic of Dual Photovoltaic and ENE-FARM Power Generation