Electricity can be used for heating in two ways:
- Resistance Heaters
- Heat Pumps
Resistance heaters use metal elements that have a high resistance to the passage of electricity. When forced to conduct electricity, they heat up. Because almost all of the electricity passing through the element is converted to heat, resistance heaters are considered almost 100% efficient. However, if the losses associated with the generation and transmission of the electricity to the site are included, the efficiency drops. Because electricity is considered such a highly refined form of energy essential for many tasks in our society, some consider it wasteful to use it simply for heating. In addition, on a Btu-for-Btu basis, electric resistance is one of the most expensive ways to heat.
Heat pumps use electricity too, but instead of using it to create heat, they use it to transfer heat from one place to another. Because it is moving rather than creating heat, they can achieve efficiencies of over 300%, meaning they provide three times more heat than they consume in electricity. Heat pumps have the advantage that, in one unit, they can both cool and heat the home.