Alternating with Direct Current

If only Thomas Edison would have joined forces with George Westinghouse, I think that we would be using electricity more efficiently today. From what I understand, Westinghouse's alternating current (AC) is best over long distances, while Edison's direct current (DC) is best over short distances. Alternating current seems to have won out due to the need to transmit electricity over long distances from the power plants to the consumers. And, when that battle was being fought a hundred years ago, either of the technologies worked to accomplish the goals of lighting homes. Now, with the widespread use of direct current consuming devices such as computers and other home electronics, it would seem that using direct current inside a home could be a better idea.

In the modern home there are so many AC/DC converters, those are the small boxes on the end of the power cables that take up so much room in the outlet and frequently get separated from the device it is meant to power. The conversion of alternating current to direct current is decentralized at each of the devices, and each device wastes energy to operate. It would seem more efficient to transmit power from the electric company using alternating current, and then perform a central conversion to direct current. Alternating current is still required for many household devices, so actually both forms would be required.

To me, the present system just seems very inefficient. Consider the example of a home PC. Electricity is generated and then transmitted all the way down to the outlet as alternating current. (Or, if solar panels are being used for power generation, the power is generated in direct current and then converted to alternating current.) Then, the battery backup converts it to direct current to charge the batter. The battery backup has to convert it back to alternating current since that is what the computer expects. Finally, the computer converts the alternating current back to direct current again because that is what the internal electronics require. Each power converts step wastes energy, if nothing else in the form of heat.

Of course not only are homes not designed for this, but neither are electronic devices. A new standard for home wiring would have to be defined to accommodate some form of direct current, possibly in different voltages (5V, 9V, 12V, 24V). There would have to be some sort of standard outlet or receptacle. And, the device manufacturers would have to use new standard plugs. All of these requirements make me believe that changing the system at this point would be nearly impossible. Which is why I wish that Mr. Westinghouse and Mr. Edison would have enjoined their technologies to define a better overall system.
Published: 2009-04-05