An Electronic Device Which Heats Water by Immersing

An Electronic Device Which Heats Water by Immersing.

Process in which electrical energy is converted to estrus

thirty kW resistance heating coils

Electric heating
is a process in which electrical free energy is converted directly to estrus free energy at around 100% efficiency, using rather inexpensive devices. Common applications include space heating, cooking, water heating and industrial processes. An
electrical heater
is an electrical device that converts an electric current into heat.[1]
The heating element within every electric heater is an electrical resistor, and works on the principle of Joule heating: an electric current passing through a resistor volition convert that electrical energy into heat energy. Most modern electric heating devices use nichrome wire equally the active element; the heating chemical element, depicted on the right, uses nichrome wire supported by ceramic insulators.

Alternatively, a heat pump can achieve effectually 300% efficiency for heating, or 3.0 Coefficient of performance, because it uses electric power only for transferring existing thermal free energy from the surrounding area, more often than not air. The rut pump uses an electric motor to bulldoze a refrigeration wheel, that draws heat energy from a source such as the ground or outside air (or the interior of a refrigerator) and directs that rut into the space to exist warmed (in instance of a fridge, the kitchen). This makes much better utilize of electric energy than direct electric heating, just requires much more expensive equipment, plus plumbing. Some heating systems can exist operated in opposite for ac so that the interior space is cooled and fifty-fifty hotter air or water is discharged outside or into the basis.

Space heating

[edit]

Space heating
is used to warm the interiors of buildings. Space heaters are useful in places where air-handling is hard, such as in laboratories. Several methods of electric infinite heating are used.

Infrared radiant heaters

[edit]

Electrical infrared radiant heating uses heating elements that reach a high temperature. The chemical element is usually packaged inside a glass envelope resembling a calorie-free bulb and with a reflector to straight the energy output away from the trunk of the heater. The element emits infrared radiation that travels through air or space until information technology hits an absorbing surface, where it is partially converted to heat and partially reflected. This heat directly warms people and objects in the room, rather than warming the air. This style of heater is particularly useful in areas through which unheated air flows. They are likewise platonic for basements and garages where spot heating is desired. More generally, they are an splendid choice for task-specific heating.

Radiant heaters operate silently and present the greatest potential danger of ignition of nearby effects due to the focused intensity of their output and lack of overheat protection. In the United Kingdom, these appliances are sometimes called electric fires, because they were originally used to supersede open fires.

The active medium of the heater depicted in this section is a coil of nichrome resistance wire within a fused silica tube, open to the atmosphere at the ends, although models be where the fused silica is sealed at the ends and the resistance alloy is not nichrome.

Convection heaters

[edit]

An electrical convection heater.

In a convection heater, the heating chemical element heats the air in contact with it by thermal conduction. Hot air is less dense than cool air, so it rises due to buoyancy, allowing more than cool air to menses in to take its identify. This sets up a convection current of hot air that rises from the heater, heats up the surrounding space, cools and and then repeats the bike. These heaters are sometimes filled with oil or thermal fluid. They are ideally suited for heating a airtight space. They operate silently and have a lower gamble of ignition chance if they brand unintended contact with furnishings compared to radiant electric heaters.

Fan heaters

[edit]

A fan heater, besides chosen a forced convection heater, is a kind of convection heater that includes an electric fan to speed up the airflow. They operate with considerable noise caused by the fan. They have a moderate adventure of ignition chance if they brand unintended contact with effects. Their advantage is that they are more meaty than heaters that use natural convection and are also cost-efficient for portable and pocket-sized room heating systems.

Storage heating

[edit]

A storage heating organization takes advantage of cheaper electricity prices, sold during low need periods such as overnight. In the United Kingdom, this is branded as Economy 7. The storage heater stores heat in clay bricks, then releases information technology during the day when required. Newer storage heaters are able to exist used with diverse tariffs. Whilst they can still be used with economy 7, they tin be used with day-time tariffs. This is due to the mod design features that are added during manufacturing. Alongside new designs the use of a thermostat or sensor has improved the efficiency of the storage heater. A thermostat or sensor is able to read the temperature of the room, and change the output of the heater appropriately.

Water can also be used equally a heat-storage medium.

Domestic electrical underfloor heating

[edit]

An electric underfloor heating organisation has heating cables embedded in the floor. Electric current flows through a conductive heating material, supplied either directly from the line voltage (120 or 240 volts) or at low voltage from a transformer. The heated cables warm the flooring past direct conduction and will switch off once information technology reaches the temperature set by the floor thermostat. A warmer flooring surface radiates heat to colder surrounding surfaces (ceiling, walls, piece of furniture.) which absorb heat and reflects all non captivated heat to nonetheless other still libation surfaces. The bike of radiation, absorption and reflection starts slowly and slows downwards slowly nearing set signal temperatures and ceases to take place once equilibrium is reached all-round. A floor thermostat or a room thermostat or combination controls the floor on/off. In the process of radiant heating a thin layer of air which is in touch with the warmed surfaces also absorbs some heat and this creates a niggling convection (air apportionment). Opposite to conventionalities people are not heated by this warmed circulating air or convection (convection has a cooling effect) but are heated by the direct radiation of the source and reflection of its surrounds. Condolement is reached at lower air temperature due to eliminating circulating air. Radiant heating experiences highest comfort levels as people’s own free energy (± 70 Watt for an adult) (must radiate out in heating season) is in residuum with its surrounds. Compared to convection heating organisation based on academic research the air temperatures may be lowered by up to 3 degrees. One variation is using tubes filled with circulating hot h2o every bit heat source for warming the floor. The heating principle remains the same. Both old style electric and warm water (hydronic) underfloor heating systems embedded in the floor structure are wearisome and cannot respond to external weather changes or internal demand/lifestyle requirements. The latest variant places specialized electrical heating systems and blankets directly nether the floor-decor and on superlative of additional insulation all placed on meridian of construction floors. Construction floors stay cold. The principle change of heat source positioning allows it to answer within minutes to changing weather and internal demand requirements such as life mode existence in/out, at work, rest, sleep, more people present/cooking, etc.

Lighting system

[edit]

In large office towers, the lighting organization is integrated along with the heating and ventilation organization. Waste matter heat from fluorescent lamps is captured in the return air of the heating system; in large buildings a substantial part of the annual heating energy is supplied by the lighting system. Still, this waste material heat becomes a liability when using air workout. Such expenses can be avoided by integrating an free energy efficient lighting arrangement that also creates an electric estrus source.[2]

Estrus pumps

[edit]

A rut pump uses an electrically driven compressor to operate a refrigeration cycle that extracts heat free energy from outdoor air, the footing or ground h2o, and moves that heat to the space to be warmed. A liquid contained inside the evaporator section of the oestrus pump boils at low pressure, absorbing heat energy from the outdoor air or the ground. The vapor is then compressed by a compressor and piped into a condenser curlicue within the building to exist heated. The oestrus from the hot dense gas is absorbed past the air in the edifice (and sometimes likewise used for domestic hot water) causing the hot working fluid to condense back into a liquid. From in that location the high pressure level fluid is passed back to the evaporator section where it expands through an orifice and into the evaporator department, completing the cycle. In the summer months, the wheel can be reversed to move heat out of the conditioned space and to the outside air.

Oestrus pumps may obtain low-grade heat from the outdoor air in balmy climates. In areas with boilerplate winter temperatures well below freezing, ground source heat pumps are more efficient than air source heat pumps because they can excerpt residuum solar heat stored in the basis at warmer temperatures than is bachelor from cold air.[3]
Co-ordinate to the United states EPA, geothermal heat pumps tin can reduce free energy consumption up to 44% compared with air source oestrus pumps and upwards to 72% compared with electric resistance heating.[iv]
The high purchase toll of a heat pump vs resistance heaters may be offset when ac is also needed.

Liquid heating

[edit]

Immersion heater

[edit]

Small domestic immersion heater, 500 W

An immersion heater has an electrical resistance heating element encased in a tube, placed in the water (or other fluid) to be heated. The heating element might exist inserted directly into the liquid, or installed inside a metallic pipe to protect against corrosion and facilitate maintenance. Portable immersion heaters may not have a control thermostat, since they are intended to exist used only briefly and nether command of an operator.

For domestic hot water supply, or industrial process hot h2o, permanently installed heating elements in an insulated hot water tank may be used, controlled by a thermostat to regulate temperature. Household units may be rated merely a few kilowatts. Industrial h2o heaters may attain 2000 kilowatts. Where off-pinnacle electric power rates are available, hot water may exist stored to use when required.

Electric shower and tankless heaters also apply an immersion heater (shielded or naked) that is turned on with the flow of water. A group of separate heaters tin exist switched to offer different heating levels. Electric showers and tankless heaters normally utilise from three to 10.5 kilowatts.

Minerals present in the water supply may precipitate out of solution and form a hard scale on the heating element surface, or may autumn to the lesser of the tank and clog water menses. Maintenance of water heating equipment may require periodic removal of accumulated scale and sediment. Where water supplies are known to exist highly mineralized, scale production tin be reduced by using depression-watt-density heating elements.[five]

Circulation heaters

[edit]

Apportionment heaters or “direct electric heat exchangers” (DEHE) apply heating elements inserted into a “trounce side” medium directly to provide the heating effect. All of the heat generated by the electric circulation heater is transferred into the medium, thus an electrical heater is 100 pct efficient. Direct electric heat exchangers or “apportionment heaters” are used to heat liquids and gases in industrial processes.[half dozen]
[vii]

Electrode heater

[edit]

With an electrode heater, there is no wire-wound resistance and the liquid itself acts as the resistance. This has potential hazards, and then the regulations governing electrode heaters are strict.

Ecology and efficiency aspects

[edit]

The efficiency of any system depends on the definition of the boundaries of the system. For an electrical energy customer the efficiency of electrical space heating is 100% because all purchased energy is converted to heat. Nevertheless, if a power plant supplying electricity is included, the overall efficiency drops drastically. For example, a fossil-fuel power station only delivers iii-5 units of electric energy for every 10 units of fuel energy released.[eight]
Even though the electric heater is 100% efficient, the amount of fuel needed to produce the heat is more than than if the fuel were burned in a furnace or boiler at the building being heated. If the same fuel could exist used for infinite heating by a consumer, it would be more efficient overall to fire the fuel at the finish user’s building. On the other hand, replacing electric heating with fossil fuel burning heaters, isn’t necessary good as information technology removes the ability to have renewable electric heating, this tin be achieved past sourcing the electricity from a renewable source.

Variations between countries generating electrical power affect concerns about efficiency and the environment. In 2015 France generated only 6% of its electricity from fossil fuels, while Australia sourced over 86% of its electricity from fossil fuels.[9]
The cleanliness and efficiency of electricity are dependent on the source.

In Sweden the use of direct electric heating has been restricted since the 1980s for this reason, and there are plans to phase it out entirely – see Oil phase-out in Sweden – while Denmark has banned the installation of direct electric space heating in new buildings for similar reasons.[10]
In the example of new buildings, depression-energy building techniques can be used which can about eliminate the need for heating, such as those congenital to the Passivhaus standard.

In Quebec, yet, electric heating is still the most popular form of home heating. According to a 2003 Statistics Canada survey, 68% of households in the province use electricity for space heating. More than ninety% of all power consumed in Quebec is generated by hydroelectric dams, which have low greenhouse gases emissions compared to fossil-fuel ability stations. Low and stable rates are charged by Hydro-Québec, the provincially owned utility.[11]

In recent years at that place has been a major trend for countries to generate low-carbon electricity from renewable sources, calculation to nuclear power and hydro-electric power which are long-standing low-carbon sources. For example, the carbon footprint of U.k. electricity per kWh in 2019 was less than half that in 2010.[8]
All the same, because of high uppercase cost, the price of electricity has not fallen and is typically 2-3 times that of burning fuel. Hence, direct electric heating may now give a similar carbon footprint to gas- or oil-fired heating, but the cost remains higher, though cheaper off-peak tariffs can reduce this event.

To provide oestrus more efficiently, an electrically driven oestrus pump can enhance the indoor temperature past extracting energy from the ground, the exterior air, or waste streams such as exhaust air. This can cut the electricity consumption to every bit footling equally 35% of that used by resistive heating.[12]
Where the master source of electrical free energy is hydroelectric, nuclear, or air current, transferring electricity via the grid can be convenient, since the resource may exist also distant for straight heating applications (with the notable exception of solar thermal free energy).

The electrification of heat of infinite and water heating is increasingly proposed equally a style forward to decarbonise the current energy system, particularly with rut pumps. In case of large-scale electrification, impacts on the electricity filigree due to potential increase in pinnacle electricity need and exposure to extreme weather condition events needs to be considered.[13]

Economic aspects

[edit]

The operation of electric resistance heaters to heat an area for long periods is costly in many regions. All the same, intermittent or partial 24-hour interval use can exist more cost efficient than whole building heating due to superior zonal control.

For example: A lunch room in an office setting has limited hours of performance. During low-employ periods a “monitor” level of heat (50 °F or ten °C) is provided by the central heating system. Peak use times between the hours of 11:00 and 14:00 are heated to “comfort levels” (70 °F or 21 °C). Significant savings can be realized in overall energy consumption, since infrared radiation losses through thermal radiation are not as big with a smaller temperature gradient both between this space and unheated exterior air, also as between the fridge and the (now cooler) lunch room.

Economically, electric oestrus can be compared to other sources of home heating by multiplying the local cost per kilowatt hour for electricity by the number of kilowatts the heater uses. Eastward.thou.: 1500-watt heater at 12 cents per kilowatt hour i.5×12=18 cents per hr.[xiv]
When comparison to burning fuel it may be useful to convert kilowatt hours to BTUs: 1.v kWh × 3412.142=5118 BTU.

Industrial electric heating

[edit]

Electric heating is widely used in industry.[15]

Advantages of electrical heating methods over other forms include precision command of temperature and distribution of heat free energy, combustion non used to develop heat, and the ability to reach temperatures not readily doable with chemic combustion. Electric heat can exist accurately applied at the precise signal needed in a procedure, at high concentration of power per unit of measurement surface area or volume. Electrical heating devices can be built in any required size and can be located anywhere within a institute. Electrical heating processes are generally clean, tranquillity, and practise not emit much byproduct oestrus to the surroundings. Electrical heating equipment has a high speed of response, lending it to rapid-cycling mass-production equipment.

The limitations and disadvantages of electric heating in industry include the higher cost of electrical energy compared to direct use of fuel, and the capital cost of both the electric heating appliance itself and the infrastructure required to evangelize big quantities of electrical free energy to the point of employ. This may be somewhat offset by in-plant (on-site) efficiency gains in using less energy overall to achieve the aforementioned consequence.

Design of an industrial heating arrangement starts with cess of the temperature required, the amount of heat required, and the feasible modes of transferring rut free energy. In addition to conduction, convection and radiation, electrical heating methods can use electric and magnetic fields to oestrus textile.

Methods of electric heating include resistance heating, electric arc heating, induction heating, and dielectric heating. In some processes (for example, arc welding), electrical current is directly applied to the workpiece. In other processes, heat is produced inside the workpiece by induction or dielectric losses. As well, estrus can be produced then transferred to the piece of work by conduction, convection or radiation.

Industrial heating processes can exist broadly categorized as low-temperature (to nigh 400 °C or 752 °F), medium-temperature (between 400 and ane,150 °C or 752 and two,102 °F), and high-temperature (beyond 1,150 °C or 2,102 °F). Low-temperature processes include baking and drying, curing finishes, soldering, molding and shaping plastics. Medium temperature processes include melting plastics and some non-metals for casting or reshaping, as well as annealing, stress-relieving and oestrus-treating metals. Loftier-temperature processes include steelmaking, brazing, welding, casting metals, cutting, smelting and the preparation of some chemicals.

See also

[edit]

  • Auxiliary ability unit of measurement
  • Primal heating
  • Diathermy
  • Dielectric heating
  • Electroslag welding
  • Electroslag remelting
  • Energy conservation
  • Head-end ability
  • Heater (types of heaters)
  • Heating, ventilation, and air conditioning
  • Hotel electric power
  • Infrared heater
  • Microwave oven
  • Renewable energy
  • Thermal efficiency
  • Thermal immersion circulator
  • Underfloor heating

References

[edit]


  1. ^


    “Electric Heater”.
    Britannica.com. The Editors of Encyclopædia Britannica.



  2. ^


    “Free energy Efficient Lighting | WBDG Whole Building Pattern Guide”.
    www.wbdg.org
    . Retrieved
    18 December
    2017
    .



  3. ^


    “Comparison of efficiency of air source rut pumps and footing source oestrus pumps”. Icax.co.uk. Retrieved
    xx December
    2013
    .



  4. ^


    “Choosing and Installing Geothermal Rut Pumps – Department of Energy”.
    Energy.gov
    . Retrieved
    sixteen Apr
    2017
    .



  5. ^


    “Immersion Heaters – Sigma Thermal”.
    Sigma Thermal
    . Retrieved
    18 December
    2017
    .



  6. ^


    “Gastech News”. 12 August 2012. Archived from the original on 22 February 2017.


  7. ^


    “Electrical Resistance Heating – Department of Energy”.
    Energy.gov
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    16 Apr
    2017
    .


  8. ^


    a




    b




    Kemp, I.C. and Lim, J.Due south. (2020).


    Pinch Analysis for Energy and Carbon Footprint Reduction: A User Guide on Process Integration for the Efficient Use of Energy, tertiary edition

    . Butterworth-Heinemann. ISBN978-0-08-102536-9.



    {{cite volume}}: CS1 maint: multiple names: authors list (link)


  9. ^

    Hannah Ritchie and Max Roser (2020) – “Fossil Fuels”. Published online at OurWorldInData.org. Retrieved from: ‘https://ourworldindata.org/fossil-fuels’; retrieved 2020-05-23

  10. ^

    The Green Electricity Illusion,
    AECB, published 2005-11-11, accessed 26 May 2007

  11. ^

    Snider, Bradley. Dwelling house heating and the surround, in
    Canadian Social Trends, Spring 2006, pp. 15–19. Ottawa: Statistics Canada.

  12. ^


    “Footing-Source Oestrus Pumps (Earth-Energy Systems)”.
    NRCan.gc.ca
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    16 Apr
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  13. ^


    Eggimann, Sven; Usher, Will; Eyre, Nick; Hall, Jim West. (2020). “How weather affects energy demand variability in the transition towards sustainable heating”.
    Free energy.
    195
    (C): 116947. doi:ten.1016/j.energy.2020.116947. S2CID 214266085.



  14. ^


    “How to summate electric energy cost of mutual household items – McGill’s Repair and Construction, LLC”.
    McGill’s Repair and Structure, LLC. 19 January 2014. Retrieved
    18 Dec
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  15. ^

    Donald G. Fink and H. Wayne Beaty,
    Standard Handbook for Electrical Engineers, Eleventh Edition, McGraw-Hill, New York, 1978, ISBN 0-07-020974-Ten, pages 21-144 to 21-188



An Electronic Device Which Heats Water by Immersing

Source: https://en.wikipedia.org/wiki/Electric_heating