AC and DC are different types of electric current. There are some significant differences and those differences are allowing for some interesting application especially with the changing face of energy awareness today. AC or alternating current is literally a current that alternates in the direction that it flows. DC is direct current and as is implied by the name the current flows only in one direction.

Alternating current replaced DC in the 1880’s as the current used in power lines because of difficulty in transmitting DC over long distances. This problem has since been remedied and direct current is now transmitted over long distances, though AC remains the current type that is supplied to houses and businesses. AC allows for transfer of energy from the consumption point back into the grid as well as from the grid to the consumption point. This has proven beneficial in the case of houses and businesses that now produce more energy than they consume. This is being made possible through the use of alternate energy sources such as solar power, wind energy and other sources. As these sources grow in homes and businesses the two-way flow of energy that AC allows is proving a fortuitous coincidence.

Direct current is used to transmit energy over long distances today despite it is not being used at consumption points (electrical receptacles in most locations). After it is transmitted it is converted back to AC before entering the consumer point. DC is also still available in common energy sources that aren’t connected to power grids. These include many batteries, fuel cells, generators and other power sources. These power sources prove effective in their uses each day. Some are incorporated into power grids and alternative energy sources.

Each type of current is fundamentally different from the other and those differences have proven them to be more suitable in some uses than the other.