ELECTRICAL HEATINGELECTRICAL HEATING

NameName : Mohammed Saad ALghamdi. : Mohammed Saad ALghamdi.

IDID : 425 10 64 93 . : 425 10 64 93 .

Day Day : Wednesday . : Wednesday .

DateDate : 09/05/1429 H. : 09/05/1429 H.

DrDr - Malik ALahmed - Malik ALahmed

OUTLINEOUTLINE

Introduction.Introduction.Definition.Definition.Electric Resistance Heating.Electric Resistance Heating.Types of Electric Resistance Heaters.Types of Electric Resistance Heaters.Mathematical analysisMathematical analysisFan heaters.Fan heaters.Conclusion.Conclusion.

IntroductionIntroduction

The energy is converted from shape The energy is converted from shape to other shapeto other shape

Such as:Such as:

Electrical energy thermal Electrical energy thermal energyenergy

DefinitionDefinition

Electric heatingElectric heating is any process in which electrical energy is any process in which electrical energy is converted to heat. Common applications include heating is converted to heat. Common applications include heating of buildings, cooking, and industrial processes.of buildings, cooking, and industrial processes.

An electric heater is an electrical appliance that converts An electric heater is an electrical appliance that converts electrical energy into heat . The heating element inside electrical energy into heat . The heating element inside every electric heater is simply an electrical resistor, and every electric heater is simply an electrical resistor, and works on the principle of joule heating: an electric current works on the principle of joule heating: an electric current flowing through a resistor converts electrical energy into flowing through a resistor converts electrical energy into heat energy.heat energy.

A heat pump uses an electric motor to drive a A heat pump uses an electric motor to drive a refrigeration cycle, drawing heat from a source such as refrigeration cycle, drawing heat from a source such as ground water or outside air and directing it into the space ground water or outside air and directing it into the space to be warmed. Such systems can deliver two or three units to be warmed. Such systems can deliver two or three units of heating energy for every unit of purchased energy.of heating energy for every unit of purchased energy.

Electric Resistance Electric Resistance HeatingHeating

Electric resistance heating converts nearly 100% Electric resistance heating converts nearly 100% of the energy in the electricity to heat. However, of the energy in the electricity to heat. However, most electricity is produced from oil, gas, or coal most electricity is produced from oil, gas, or coal generators that convert only about 30% of the generators that convert only about 30% of the fuel's energy into electricity. Because of electricity fuel's energy into electricity. Because of electricity generation and transmission losses, electric heat is generation and transmission losses, electric heat is often more expensive than heat produced in the often more expensive than heat produced in the home or business using combustion appliances, home or business using combustion appliances, such as natural gas, propane, and oil furnaces.such as natural gas, propane, and oil furnaces.

Types of Electric Resistance Types of Electric Resistance HeatersHeaters

Electric FurnacesElectric FurnacesElectric Baseboard HeatersElectric Baseboard HeatersElectric Wall HeatersElectric Wall HeatersElectric Thermal StorageElectric Thermal StorageControl SystemsControl Systems

Mathematical analysisMathematical analysis

According to According to Joule's LawJoule's Law, the heat power produced , the heat power produced by a resistor is:by a resistor is:

PP = = IVIV wherewherePP is the power in is the power in wattswatts II is the current in is the current in amperesamperes, and , and VV is the potential difference in is the potential difference in voltsvolts, , and according to and according to Ohm's LawOhm's Law II and and VV are related as are related as

follows:follows:VV = = IRIR

wherewhereRR is the resistance of the heating element, in is the resistance of the heating element, in ohmsohms. .

Fan heatersFan heaters

A fan heater is a variety of convection A fan heater is a variety of convection heater that includes an electric fan to speed heater that includes an electric fan to speed up the airflow. up the airflow.

This reduces the thermal resistance between This reduces the thermal resistance between the heating element and the surroundings, the heating element and the surroundings, allowing heat to be transferred more allowing heat to be transferred more quickly.quickly.

conclusionconclusion

Although they all use the same Although they all use the same physical principle to generate heat, physical principle to generate heat, electric heaters differ in the way they electric heaters differ in the way they deliver that heat to the environment.deliver that heat to the environment.