Today’s power grid was built upon 19th century thinking and building processes. It wasn’t even based upon the ideas of the most forward-thinking inventor of the time, Thomas Edison, but ended up being built based upon the designs of Edison’s competitor George Westinghouse.The growing support for a smart grid is really a call to modernise. What will result is a transmission system more in line with what Edison considered to be ideal more than a century ago: a distributed system or multiple generation sources. However, when the current system began to take shape in 1891 it became Westinghouse’s centralised system though he probably wouldn’t recognise what it has become today.America’s vast “centralised” power grid consists of more than 16,000 power plants connected by transmission lines stretching hundreds of thousands of miles in order to meet the power needs of millions of consumers. Each year, the United States in total uses up 4 billion megawatts of power – a colossal amount that is difficult to fathom.
Americans for generations now have assumed that by simply flipping a switch a light will turn on or with the press of a button on the remote the TV will switch on. Today, the United States uses three regional synchronous grids: one for the East, one for the West, and one for Texas.
This conglomeration came about as a result of the properties of alternating current (AC) electricity, favoured by Westinghouse, where the electric current switches direction at regular time intervals. For a power grid to properly distribute AC power every electron within the entire system must switch direction at precisely the same time or else a cataclysmic system crash will occur and everyone loses power.
It would be nearly impossible to synchronise these alternating currents nationally, so as a result we have three regional grids properly timed independently that are connected together through high-capacity direct current (DC) power lines.
The power grid as we know it has certainly functioned as needed for as long as we’ve had it in place but an adaptive, efficient smart grid could do a better job. A smart grid would be more reliable, would be interactive at all points in the transmission system, would be flexible, and would become national without the big DC power connectors.
The current power supply is enabled by an overly complex system of power substations and switches that connect power from the generation source to homes and businesses. Consumers of energy do not have a static demand for power – it fluctuates wildly throughout the day and at different times of the year. Powerful weather systems regularly disrupt the system at the local level and sometimes a local failure triggers a catastrophic blackout such as the one that occurred in the Northeast in 2003.
A smart grid would be a much more reliable power supply because it could “heal itself” much like a computer network that regularly finds the most efficient route from point A to point B. Problems within the smart grid are instantly detected, isolated, and dealt with automatically with little or no human intervention.
Interactivity in the smart grid establishes communications between supplier and consumer. Today, current in the grid only flows in one direction – from the power plant to the consumer without any sort of monitoring or measurement in real time. Because power grid operators have no vision into the supply or the demand they must keep excess capacity on hand – oftentimes this excess is wasted and never used except during times of peak demand.
Peak demand, on average, occurs on about 10 days a year but the other 355 days utility companies must still have excess capacity on hand “just in case.” This is not a very efficient way to generate and supply power obviously. The smart grid will interact with energy consumers down to the appliance level and could adjust the level of the power supply in real-time according to the actual demand of the consumer.
A flexible power supply is where the smart grid would finally align the system with the distributed system that Edison envisioned in the 19th century. Today’s “blind” supply is provided largely by coal-fired plants that are constantly operating at capacity. At the time, Westinghouse and other thinkers of the 19th century envisioned a world of plentiful resources without considering waste. Of course that perspective doesn’t fly in today’s environmentally-conscious world.
The smart grid would integrate widely distributed power sources including wind and solar energy. Power could be generated wherever it is found instead of where it is needed. It doesn’t even have to be constant, as wind and solar power aren’t. When the wind is blowing or the sun is shining the smart grid will tap into those sources.
The smart grid would also become a national transmission system for the first time. The vast wind sources in Middle America could be sent east or west. To minimise loss in the transmission system the DC connector lines between regional grids must be replaced with a single high-capacity line that crosses the country and incorporates distributed power sources along the way.
