Smart Energy Grid

Conventional power lines are expensive, ugly and wasteful, they can lose 14 percent of their energy from the resistance of the copper cables. A major aspect of the "smart energy grid" is a new set of long-distance power lines to carry electricity from renewable energy like wind and solar, usually situated in remote areas, to dens populated urban locations.

Instead of copper new superconducting cables should be applied that haven’t such problems. A set of cables carrying five Giga watts of power, the equivalent output of about five big nuclear power plants, can fit into an underground pipe of just 90 cm (3 feet) in diameter. Containing a cooling system, because superconductors work only at the temperature of liquid nitrogen, about minus-170ºC. Nitrogen is relatively cheap to manufacture. The cooling equipment draws some energy from the cable, but still far less than the 14% losses in copper cable.

If the world is going to start using climate-friendly renewable energies, it'll require new transmission lines anyway. As a result new power cables will have to link the sources of renewable energy to consumers. It's a choice between ugly, inefficient overhead lines and a pipe buried underground along existing highways, while the investment required is roughly the same as for conventional lines.

Moreover promoting the adoption of renewable energy technology, a smart energy grid would be even better for the environment.

Around the world billions of dollars are being invested in clean-energy technologies of one sort or another, from solar arrays to wind turbines etc. But there is a problem waiting in the power grid that links them together. Green sources of power tend to be generated intermittently, which makes it difficult to integrate them into the existing grid. And when it comes to electric cars, the charging of those vehicles has to be carefully managed. In order to accommodate the flow of energy between new sources of supply and new forms of demand, in other words the world’s electrical grids has going to become a lot smarter.

A great problem of existing grids is the transparency at the distribution side of the system. Most people have little idea how much electricity they are using until they are presented with the bill. Nor do most people know what proportion of their power was generated by nuclear, coal, gas or some form of renewable energy, or what emissions were produced in the process. In the event of a power cut, it is the customer who alerts the utility, after the supplier fixes the problem manually. “I can’t think of another industry that still has that lack of visibility over its networks,” says New Energy Finance, a research firm in London.

Adding digital sensors and remote controls to the transmission and distribution system would make it smarter, greener and more efficient. Such a “smart grid” or an “Energy Internet” would be far more responsive, interactive and transparent than today’s grid. It would be able to cope with new sources of renewable power, enabling the co-ordinated charging of electric cars, providing information to consumers about their usage and allow utilities to monitor and control their networks more efficiently. And on top all this would help reduce greenhouse-gas emissions. “We have a fundamental belief that a fully effective smart grid is going to radically change the way an energy grid operates,” says Michael Carlson, at Xcel Energy, a power company.

Most important would be the introduction of smart meters, which track electricity use in real-time and can transmit that information back to the power company. Commercial and industrial customers have used smart meters for decades.

Smart meters establish a two-way data connection between the customer and the power company, by sending information over a communications network that may include power-line, radio or cellular-network connections. Once smart meters are installed, power companies can determine the location of outages more easily, and no longer need to send staff to read meters, or to turn the power on or off at a particular property. Smart meters also help to limit the theft of electricity. So far the pioneer in this field is Enel in Italy that has more than 30m smart meters deployed in its customer network since 2001.

But the smart meter is only the first step. Eventually smart meters will communicate with smart thermostats, appliances and other devices, giving people a much clearer view of how much electricity they are consuming. Customers will be able to access that information via read-outs in their homes or web-based portals, through which they will be able to set temperature preferences for their thermostats, for example, or opt in or out of programs that let them use cleaner energy sources, such as solar or wind power.

Further it will provide utilities with better control, while smart meters also give them more flexibility. In particular, they can vary the price of electricity throughout the day in response to demand. Informing people when electricity is more expensive as demand is high to encourage them to do their laundry when demand is low and electricity is cheaper.

Showing real-time price and usage information on a display so that consumers can decide whether to turn on the washing machine could do this. Studies have found that when people are made aware of how much power they are using, they reduce their use by about 7%. With added incentives, people cut back their electricity use during peaks in demand by 15% or more. But eventually it should be possible to do it automatically, so that for example the dishwasher waits for the price to fall below a certain level before switching on, or the air-conditioner turns off when the price goes up.

The advantage from the utility’s point of view is that it becomes easier to balance supply and demand by reducing consumption at times of peak demand, such as during very hot or cold spells, when people crank up their air-conditioners or heaters. As well as improving the stability of the system, it could also enable utilities to postpone the construction of new power stations, or even do without them altogether, by reducing the peak level of demand that they have to meet.

Smart grids will make it easier to coordinate the intermittent and dispersed sources of power, from rooftop solar panels or backyard wind-turbines, for example. And, of course, a smart grid could also help manage the charging of electric vehicles. The best time to charge vehicles is at night, when lots of cheap electricity is available. “If we don’t do that, then we will add to peak loads and we’ll have to build huge amounts of infrastructure to handle our vehicles,” says Robert Pratt of PNNL. The flow of energy between the grid and electric cars need not be one-way. With millions of electric cars plugged in at any one time, they could act as an enormous energy-storage system, absorbing excess power from wind turbines on windy nights, for example, but also feeding power back into the grid if necessary, an approach called “vehicle to grid” in short - V2G, if the wind suddenly drops.

If Governments want to inject money into the economy, this Smart Energy Grid project is the opportunity to make valuable long lasting investments that support and contribute to future generations as well.