![EcoCute](https://upload.wikimedia.org/wikipedia/commons/8/84/EcoCute.jpg)
The EcoCute is an
energy-efficient electric
heat pump
A heat pump is a device that can heat a building (or part of a building) by transferring thermal energy from the outside using a refrigeration cycle. Many heat pumps can also operate in the opposite direction, cooling the building by removing h ...
,
water heating
Water heating is a heat transfer process that uses an energy source to heat water above its initial temperature. Typical domestic uses of hot water include cooking, cleaning, bathing, and space heating. In industry, hot water and water heated t ...
and supply system that uses heat extracted from the air to heat water for domestic, industrial and
commercial
Commercial may refer to:
* a dose of advertising conveyed through media (such as - for example - radio or television)
** Radio advertisement
** Television advertisement
* (adjective for:) commerce, a system of voluntary exchange of products and s ...
use. Instead of the more conventional
ammonia
Ammonia is an inorganic compound of nitrogen and hydrogen with the formula . A stable binary hydride, and the simplest pnictogen hydride, ammonia is a colourless gas with a distinct pungent smell. Biologically, it is a common nitrogenous was ...
or
haloalkane gas
Gas is one of the four fundamental states of matter (the others being solid, liquid, and plasma).
A pure gas may be made up of individual atoms (e.g. a noble gas like neon), elemental molecules made from one type of atom (e.g. oxygen), or ...
es, EcoCute uses
supercritical carbon dioxide
Carbon dioxide (chemical formula ) is a chemical compound made up of molecules that each have one carbon atom covalently double bonded to two oxygen atoms. It is found in the gas state at room temperature. In the air, carbon dioxide is transpar ...
as a
refrigerant
A refrigerant is a working fluid used in the heat pump and refrigeration cycle, refrigeration cycle of air conditioning systems and heat pumps where in most cases they undergo a repeated phase transition from a liquid to a gas and back again. Ref ...
. The technology offers a means of
energy conservation
Energy conservation is the effort to reduce wasteful energy consumption by using fewer energy services. This can be done by using energy more effectively (using less energy for continuous service) or changing one's behavior to use less service (f ...
and reduces the emission of
greenhouse gas
A greenhouse gas (GHG or GhG) is a gas that Absorption (electromagnetic radiation), absorbs and Emission (electromagnetic radiation), emits radiant energy within the thermal infrared range, causing the greenhouse effect. The primary greenhouse ...
.
Etymology
The name of the EcoCute comes from the Japanese phrase , which literally means "natural refrigerant heat pump water heater". ''Eco'' is a contraction of either
ecology
Ecology () is the study of the relationships between living organisms, including humans, and their physical environment. Ecology considers organisms at the individual, population, community, ecosystem, and biosphere level. Ecology overlaps wi ...
or
economical
An economic system, or economic order, is a system of production, resource allocation and distribution of goods and services within a society or a given geographic area. It includes the combination of the various institutions, agencies, entitie ...
and ''Cute'' is a near homonym to ; literally "supply hot water".
History
Modern chemical refrigeration techniques developed after the proposal of the
Carnot cycle
A Carnot cycle is an ideal thermodynamic cycle proposed by French physicist Sadi Carnot in 1824 and expanded upon by others in the 1830s and 1840s. By Carnot's theorem, it provides an upper limit on the efficiency of any classical thermodynam ...
in 1824.
Jacob Perkins
Jacob Perkins (9 July 1766 – 30 July 1849) was an American inventor, mechanical engineer and physicist. Born in Newburyport, Massachusetts, Perkins was apprenticed to a goldsmith. He soon made himself known with a variety of useful mechanical ...
invented an
ice
Ice is water frozen into a solid state, typically forming at or below temperatures of 0 degrees Celsius or Depending on the presence of impurities such as particles of soil or bubbles of air, it can appear transparent or a more or less opaq ...
-making machine that used
ether
In organic chemistry, ethers are a class of compounds that contain an ether group—an oxygen atom connected to two alkyl or aryl groups. They have the general formula , where R and R′ represent the alkyl or aryl groups. Ethers can again be c ...
in 1843, and Edmond Carré built a
refrigerator
A refrigerator, colloquially fridge, is a commercial and home appliance consisting of a thermally insulated compartment and a heat pump (mechanical, electronic or chemical) that transfers heat from its inside to its external environment so th ...
that used
water
Water (chemical formula ) is an inorganic, transparent, tasteless, odorless, and nearly colorless chemical substance, which is the main constituent of Earth's hydrosphere and the fluids of all known living organisms (in which it acts as a ...
and
sulfuric acid
Sulfuric acid (American spelling and the preferred IUPAC name) or sulphuric acid ( Commonwealth spelling), known in antiquity as oil of vitriol, is a mineral acid composed of the elements sulfur, oxygen and hydrogen, with the molecular formu ...
in 1850. In Japan,
Fusanosuke Kuhara
was an entrepreneur, politician and cabinet minister in the pre-war Empire of Japan.
Biography
Kuhara was born in Hagi, Yamaguchi Prefecture into a family of ''sake'' brewers. His brother was the founder of Nippon Suisan Kaisha and his uncle F ...
, founder of
Hitachi, Ltd.
() is a Japanese multinational conglomerate corporation headquartered in Chiyoda, Tokyo, Japan. It is the parent company of the Hitachi Group (''Hitachi Gurūpu'') and had formed part of the Nissan ''zaibatsu'' and later DKB Group and Fuyo ...
, made an
air conditioner for his own home use using compressed CO
2 as a refrigerant.
In 1930
Thomas Midgley Jr.
Thomas Midgley Jr. (May 18, 1889 – November 2, 1944) was an American mechanical and chemical engineer. He played a major role in developing leaded gasoline (tetraethyl lead) and some of the first chlorofluorocarbons (CFCs), better known i ...
discovered dichlorodifluoromethane, a chlorinated fluorocarbon (
CFC) known as
freon
Freon ( ) is a registered trademark of the Chemours Company and generic descriptor for a number of halocarbon products. They are stable, nonflammable, low toxicity gases or liquids which have generally been used as refrigerants and as aerosol prop ...
. CFCs rapidly replaced traditional refrigerant substances, including CO
2 (which proved hard to compress for domestic use
[The rediscovery of ]
SHECCO), for use in
heat pumps
A heat pump is a device that can heat a building (or part of a building) by transferring thermal energy from the outside using a refrigeration cycle. Many heat pumps can also operate in the opposite direction, cooling the building by removing h ...
and
refrigerators
A refrigerator, colloquially fridge, is a commercial and home appliance consisting of a thermally insulated compartment and a heat pump (mechanical, electronic or chemical) that transfers heat from its inside to its external environment so th ...
. But from the 1980s CFCs began to lose favor as refrigerant when their damaging effects on the
ozone layer
The ozone layer or ozone shield is a region of Earth's stratosphere that absorbs most of the Sun's ultraviolet radiation. It contains a high concentration of ozone (O3) in relation to other parts of the atmosphere, although still small in rela ...
were discovered. Two alternative types of refrigerant, hydrofluorocarbons (
HFCs
High-fructose corn syrup (HFCS), also known as glucose–fructose, isoglucose and glucose–fructose syrup, is a sweetener made from corn starch. As in the production of conventional corn syrup, the starch is broken down into glucose by enzym ...
) and hydrochlorofluorocarbons (
HCFCs
Chlorofluorocarbons (CFCs) and hydrochlorofluorocarbons (HCFCs) are fully or partly halogenated hydrocarbons that contain carbon (C), hydrogen (H), chlorine (Cl), and fluorine (F), produced as volatile derivatives of methane, ethane, and propa ...
), also lost favor when they were identified as
greenhouse gases
A greenhouse gas (GHG or GhG) is a gas that absorbs and emits radiant energy within the thermal infrared range, causing the greenhouse effect. The primary greenhouse gases in Earth's atmosphere are water vapor (), carbon dioxide (), methane ...
(additionally, HCFCs were found to be more damaging to the ozone layer than originally thought). The
Vienna Convention for the Protection of the Ozone Layer
The Vienna Convention for the Protection of the Ozone Layer is a multilateral environmental agreement signed in 1985 that provided frameworks for international reductions in the production of chlorofluorocarbons due to their contribution to the d ...
, the
Montreal Protocol
The Montreal Protocol is an international treaty designed to protect the ozone layer by phasing out the production of numerous substances that are responsible for ozone depletion
Ozone depletion consists of two related events observed sinc ...
and the
Kyoto Protocol
The Kyoto Protocol was an international treaty which extended the 1992 United Nations Framework Convention on Climate Change (UNFCCC) that commits state parties to reduce greenhouse gas emissions, based on the scientific consensus that (part ...
call for the complete abandonment of such refrigerants by 2030.
In 1989, amid international concern about the effects of
chlorofluorocarbons
Chlorofluorocarbons (CFCs) and hydrochlorofluorocarbons (HCFCs) are fully or partly halogenated hydrocarbons that contain carbon (C), hydrogen (H), chlorine (Cl), and fluorine (F), produced as volatile derivatives of methane, ethane, and propan ...
and hydrochlorofluorocarbons on the ozone layer, scientist
Gustav Lorentzen
Gustav Lorentzen (28 September 1947 – 21 April 2010), also known by his stage name Ludvigsen, was a Norwegian singer-songwriter, best known from being half of the successful duo Knutsen & Ludvigsen, alongside Øystein "Knutsen" Dolmen. He went ...
and
SINTEF
SINTEF ( no, Stiftelsen for industriell og teknisk forskning), headquartered in Trondheim, Norway, is an independent research organization founded in 1950 that conducts contract research and development projects. SINTEF has 2000 employees from 7 ...
patented a method for using CO
2 as a refrigerant in heating and cooling. Further research into CO
2 refrigeration was then conducted at
Shecco (Sustainable Heating and Cooling with CO
2) in
Brussels
Brussels (french: Bruxelles or ; nl, Brussel ), officially the Brussels-Capital Region (All text and all but one graphic show the English name as Brussels-Capital Region.) (french: link=no, Région de Bruxelles-Capitale; nl, link=no, Bruss ...
,
Belgium
Belgium, ; french: Belgique ; german: Belgien officially the Kingdom of Belgium, is a country in Northwestern Europe. The country is bordered by the Netherlands to the north, Germany to the east, Luxembourg to the southeast, France to th ...
, leading to increasing use of CO
2 refrigerant technology in Europe.
In 1993 the Japanese company
Denso, in collaboration with Gustav Lorentzen, developed an
automobile
A car or automobile is a motor vehicle with Wheel, wheels. Most definitions of ''cars'' say that they run primarily on roads, Car seat, seat one to eight people, have four wheels, and mainly transport private transport#Personal transport, pe ...
air conditioner using CO
2 as a refrigerant. They demonstrated the invention at the June 1998 International Institute of Refrigeration/Gustav Lorentzen Conference.
[Technology of Car air conditioner blooms as EcoCute]
Denso After the conference, CRIEPI (
Central Research Institute of Electric Power Industry) and TEPCO (
The Tokyo Electric Power Company
, also known as or TEPCO, is a Japanese electric utility holding company servicing Japan's Kantō region, Yamanashi Prefecture, and the eastern portion of Shizuoka Prefecture. This area includes Tokyo. Its headquarters are located in Uchis ...
) approached Denso about developing a prototype air conditioner using natural refrigerant materials instead of freon. Together they produced 30
prototype
A prototype is an early sample, model, or release of a product built to test a concept or process. It is a term used in a variety of contexts, including semantics, design, electronics, and Software prototyping, software programming. A prototyp ...
EcoCute units for a year-long experimental installation at locations throughout
Japan
Japan ( ja, 日本, or , and formally , ''Nihonkoku'') is an island country in East Asia. It is situated in the northwest Pacific Ocean, and is bordered on the west by the Sea of Japan, while extending from the Sea of Okhotsk in the north ...
, from the cold climate of
Hokkaidō
is Japan's second largest island and comprises the largest and northernmost prefecture, making up its own region. The Tsugaru Strait separates Hokkaidō from Honshu; the two islands are connected by the undersea railway Seikan Tunnel.
The la ...
to hotter
Okinawa
is a prefecture of Japan. Okinawa Prefecture is the southernmost and westernmost prefecture of Japan, has a population of 1,457,162 (as of 2 February 2020) and a geographic area of 2,281 km2 (880 sq mi).
Naha is the capital and largest city ...
. After this successful
feasibility study
A feasibility study is an assessment of the practicality of a project or system. A feasibility study aims to objectively and rationally uncover the strengths and weaknesses of an existing business or proposed venture, opportunities and threats pr ...
, Denso obtained a patent to compress CO
2 refrigerant for use in a heat pump from SINTEF in September 2000.
[EcoCute](_blank)
Japan Patent Office
The is a Japanese governmental agency in charge of industrial property right affairs, under the Ministry of Economy, Trade and Industry. The Japan Patent Office is located in Kasumigaseki, Chiyoda, Tokyo and is one of the world's largest pa ...
Society
The first commercial domestic EcoCute was marketed in Japan by
Corona Corporation
Corona (from the Latin for 'crown') most commonly refers to:
* Stellar corona, the outer atmosphere of the Sun or another star
* Corona (beer), a Mexican beer
* Corona, informal term for the coronavirus SARS-CoV-2, which causes the COVID-19 di ...
in May 2001, and several manufacturers sold 1.5 million units there by October, 2008.
FEPC reported 2 million EcoCute units had been delivered by end of October 2009, with the equivalent CO
2 absorption of 9400 km
2 of
forest
A forest is an area of land dominated by trees. Hundreds of definitions of forest are used throughout the world, incorporating factors such as tree density, tree height, land use, legal standing, and ecological function. The United Nations' ...
.
Features and demand
In Japan in 1998, water heating () accounted for 33.8% of typical domestic energy consumption, with air conditioner and
kerosene heater
A kerosene heater, also known as a paraffin heater, is typically a portable, unvented, kerosene-fueled, space (i.e., convectional) heating device. In Japan and other countries, they are a primary source of home heat. In the United States and ...
heating accounting for another 26.9% and cooling by air conditioner another 2.3%. Most of the remaining 37% was spent on electrical home appliances, a field where 21st-century innovations in energy conservation began to make considerable energy savings.
[What is EcoCute](_blank)
TEPCO
, also known as or TEPCO, is a Japanese electric utility holding company servicing Japan's Kantō region, Yamanashi Prefecture, and the eastern portion of Shizuoka Prefecture. This area includes Tokyo. Its headquarters are located in Uchisaiw ...
This left hot water supply as the most difficult area for energy conservation, leaving a gap in the market for the EcoCute. By January 2005, 26 Japanese companies were producing more than 450 models of EcoCute machines, and sales of domestic units increased 130–150% each year between 2001 and 2005.
Denso first introduced the EcoCute outside Japan at the
COP9 Milan
Milan ( , , Lombard: ; it, Milano ) is a city in northern Italy, capital of Lombardy, and the second-most populous city proper in Italy after Rome. The city proper has a population of about 1.4 million, while its metropolitan city h ...
,
Italy
Italy ( it, Italia ), officially the Italian Republic, ) or the Republic of Italy, is a country in Southern Europe. It is located in the middle of the Mediterranean Sea, and its territory largely coincides with the homonymous geographical re ...
on December 9, 2003. From 2007, Denso began concentrating on marketing the EcoCute in the
EU.
In Japan, the Japanese government incorporated the EcoCute into its CO
2 reduction program under the Kyoto Protocol, mandating the installation of 5.2 million units in commercial and domestic properties by 2010.
The cost of EcoCute is approximately 500 thousand
Japanese yen
The is the official currency of Japan. It is the third-most traded currency in the foreign exchange market, after the United States dollar (US$) and the euro. It is also widely used as a third reserve currency after the US dollar and the ...
as of February–March 2009.
EcoCute machine basics
An EcoCute machine or system consists of a heat pump and
hot water
Water heating is a heat transfer process that uses an energy source to heat water above its initial temperature. Typical domestic uses of hot water include cooking, cleaning, bathing, and space heating. In industry, hot water and water heated t ...
storage unit. The
sealed components are serially connected with refrigerant CO
2 gas in
circulation.
# At the first stage, a
heat exchanger
A heat exchanger is a system used to transfer heat between a source and a working fluid. Heat exchangers are used in both cooling and heating processes. The fluids may be separated by a solid wall to prevent mixing or they may be in direct contac ...
collects heat from the air outside to use as energy for the refrigerant. Air flow is usually obtained using a
centrifugal fan
A centrifugal fan is a mechanical device for moving air or other gases in a direction at an angle to the incoming fluid. Centrifugal fans often contain a ducted housing to direct outgoing air in a specific direction or across a heat sink; such ...
; in cold areas with ambient temperatures around −20 to −25°C an
auxiliary
Auxiliary may refer to:
* A backup site or system
In language
* Auxiliary language (disambiguation)
* Auxiliary verb
In military and law enforcement
* Auxiliary police
* Auxiliaries, civilians or quasi-military personnel who provide support of ...
fan heater
A fan heater, also called a blow heater, is a heater that works by using a fan to pass air over a heat source (e.g. a heating element). This heats up the air, which then leaves the heater, warming up the surrounding room. They can heat an en ...
is attached.
# A
gas compressor
A compressor is a mechanical device that increases the pressure of a gas by reducing its volume. An air compressor is a specific type of gas compressor.
Compressors are similar to pumps: both increase the pressure on a fluid and both can transp ...
is used to increase the temperature of the gaseous CO
2 refrigerant to around 100°C under pressure of 10
M Pa via
adiabatic compression. The carbon dioxide becomes a supercritical fluid. Several types of compressors can be used, including dual layer cylindrical compressors,
scroll compressor
A scroll compressor (also called ''spiral compressor'', scroll pump and scroll vacuum pump) is a device for compressing air or refrigerant. It is used in air conditioning equipment, as an automobile supercharger (where it is known as a scroll ...
s, and dual stage
rotary compressors.
# At the second stage a heat exchanger transfers energy from the hot refrigerant into water to produce hot water. Water temperatures around 5°C and up are suitable at this stage.
# Finally, ejector
or expansion
valves
A valve is a device or natural object that regulates, directs or controls the flow of a fluid (gases, liquids, fluidized solids, or slurries) by opening, closing, or partially obstructing various passageways. Valves are technically fitting ...
reduce pressure on the refrigerant, letting it cool via
adiabatic expansion
In thermodynamics, an adiabatic process (Greek: ''adiábatos'', "impassable") is a type of thermodynamic process that occurs without transferring heat or mass between the thermodynamic system and its environment. Unlike an isothermal process ...
and revert to CO
2 gas.
The EcoCute can derive two to five units of heat energy from ambient air for every unit of input electrical energy. It produces three to five units of hot water energy, resulting in reduced CO
2 emissions compared to water heating via electricity or
natural gas
Natural gas (also called fossil gas or simply gas) is a naturally occurring mixture of gaseous hydrocarbons consisting primarily of methane in addition to various smaller amounts of other higher alkanes. Low levels of trace gases like carbo ...
. To produce 90°C hot water, an EcoCute consumes 66% less electricity than an electric water heater, and costs 80% less than heating water via natural gas in Japan. Also, by reducing use of fossil fuels, the EcoCute results in more than 50% reductions in CO
2 emissions
Not considering upstream losses of input source energy, the EcoCute's
COP is 3.8 in industrial use, while electric power water heating is 1.0, and gas
boiler
A boiler is a closed vessel in which fluid (generally water) is heated. The fluid does not necessarily boil. The heated or vaporized fluid exits the boiler for use in various processes or heating applications, including water heating, central h ...
is 0.88 including
pilot light
Merker Tankless water heating, tankless gas-fired water heater from the 1930s, with pilot light clearly visible through the aperture in the front cover. The large opening allowed for the manual lighting of the pilot light by a lit match or taper
...
loss.
Others
is a registered
trademark
A trademark (also written trade mark or trade-mark) is a type of intellectual property consisting of a recognizable sign, design, or expression that identifies products or services from a particular source and distinguishes them from others ...
(No. 4575216 – Japan)
Patents application on Heating and cooling by natural refrigerant
page 3/24 bottom, note No.10, May 15, 2003, Japan Patent Office of Kansai Electric Power Company
, also known as , is an electric utility with its operational area of Kansai region, Japan (including the Keihanshin megalopolis).
The Kansai region is Japan's second-largest industrial area, and in normal times, its most nuclear-reliant. B ...
.
See also
* Transcritical cycle
A transcritical cycle is a closed thermodynamic cycle where the working fluid goes through both subcritical and supercritical states. In particular, for power cycles the working fluid is kept in the liquid region during the compression phase ...
* R-744
Carbon dioxide (chemical formula ) is a chemical compound made up of molecules that each have one carbon atom covalent bond, covalently double bonded to two oxygen atoms. It is found in the gas state at room temperature. In the air, carbon diox ...
References
External links
Mayekawa Global ECO CUTE
{{DEFAULTSORT:Ecocute
Heat pumps
Consumer electronics
Heating, ventilation, and air conditioning
Energy conservation