Source:JASE-W Japanese Smart Energy Products & Technologies https://www.jase-w.eccj.or.jp/technologies/index.html

S5 renewable energy R-04 Keywords Y2 device Z4 electricity L Technical Services Heat Pump and Thermal Storage Technology Center of Japan

Air/Heat Pump Water Heater with Natural-Refrigerant

Features

u A high efficient water heating system that uses heat in the air to boil water. - Developed in 2001. - Achieves heat energy for water heating with less than 1/3 of the electricity.

u Low running costs - With its high efficiency, less power is consumed and running costs can be significantly reduced by the utilization of cheaper nighttime electricity.

u Dramatic reduction of household energy consumption - Approximately 30% of total energy in an average Japanese household is used for the hot water supply. Energy-saving water heaters contributes significant energy conservation. - Dramatic CO2 emission reductions are achieved when compared to conventional fossil-fuel burning water heaters.

u Eco-friendry natural refrigerant (CO2 refrigerant) is used.

Basic Concept or Summary ・ The “Eco-Cute” water heater uses heat in the air. It’s officially known as Heat Pump Water Heater with Natural-Refrigerant. ・ Like hot and cold, untouched and unused heat energy in the air and water abounds. Heat pump technology utilizes this thermal energy for various uses such as air conditioning and hot water/water supply. ・ Heat in the air and water—yet unutilized—is used instead of fossil fuels, making this water heater energy-efficient.

・ On sale since 2001, the Eco-Cute is the world’s first heat pump water heater to use natural CO2 as refrigerant. Until then, most water heaters were combustion type (gas or petroleum water heaters) or electric type (electric water heaters), with a few solar-powered water heaters and virtually there were no other types. ・ Eco-Cute is combination of “eco” from economy and ecology and kyuto, the Japanese word for hot water supply (pronounced like “cute”).

u Natural Refrigerant Heat Pump Water Heater EcoCute Equipment Overview and Hot Water Supply Mechanism

Kitchen

Compressor Adjustment Electric Energy 1 Water Valve Hot Water

Atmospheric Thermal Energy 2 or more Heat Supply Washroom Exchanger Obtained Hot Water

Air Heat Exchanger Supply Energy Bath

or more CO2 Water 1+2 Refrigeration heating =3 or more 3 or Cycle more

Expansion Pump Valve Water Supply

Heat Pump Unit Hot Water Storage Unit Heat Pump Unit Hot Water Storage Unit Source:JASE-W Japanese Smart Energy Products & Technologies https://www.jase-w.eccj.or.jp/technologies/index.html

Effects or Remarks R-04

Primary energy Incineration equipment

Fossil fuel Quantity of heat Efficiency: 90 % Reduction in 44 Waste heat fossil fuel consumption by approx. 40 % Eco Cute Average power generation efficiency of power plants Quantity Approx. 37 % Coefficient of of heat Performance = 3.0 COP(Coefficient of performance) 170 Generation loss Transmission loss

u Compared to flash urban gas-powered water heaters, the Eco-Cute reduces initial energy used 40%. u The natural refrigerant (CO2) used in the Eco-Cute does not destroy the ozone layer. Additionally, since CO2 generated in industrial and manufacturing processes is used as refrigerant, the Eco-Cute promotes the recycling of resources. u Since its launch in 2001, cumulative shipments have exceeded 7 million units.

Installation in Practice or Schedule Domestic u Natural Refrigerant Heat Pump Water Heaters

Trends in Cumulative EcoCute Shipments

Jun. 2020 Over 7 million [10,000 units] 800 Jun. 2018 Over 6 million 707 692 700 Mar. 2016 Over 5 million 639 591 547 600 Oct. 2013 Over 4 million 504 500 463 Aug. 2011 Over 3 million 422 376 400 Oct.2009 Over 2 million 331 282 300 225 200 174 124 83 100 48 25 0.3 4 12 0 [FY]

Contact: Heat Pump and Thermal Storage Technology Center of Japan International & Technical Research Department 1-28-5 Hulic Kakigaracho Bldg., 6F, Kakigaracho Nihonbashi, Chuo-ku,Tokyo, Japan Tel: +81-3-5643-2404 Fax: +81-3-5641-4501 URL: http://www.hptcj.or.jp/e/index.html