Smart Grids are electricity transmission systems that offer many potential improvements over the existing grid system, including increased reliability and reduced energy consumption. It is estimated that the Smart Grid market will be worth $100 billion in 2030. This edition of SciencePages focuses on how Smart Grids differ from our existing grid system and examines regional, national and international policies, as well as privacy and pricing issues.
What is a Smart Grid?
The present North American power grid includes nearly 3200 utility companies. It allows a one-way flow of electricity from centralized generators to consumers and a limited exchange of real-time information. A Smart Grid uses advanced digital communication to enable a two-way flow of both electricity and information. This allows electricity generation, delivery and load to be adjusted for optimal performance. Changes in the way customers record, pay for and manage energy consumption can help reduce the power system’s peak load – the period of time during the day when energy demand is highest.
Integrating Renewable Energy
Although it varies by province, Canada’s energy mix is dominated by hydroelectric power, followed by coal and nuclear power. A Smart Grid can accommodate intermittent power sources such as wind turbines and solar arrays, whose output may not coincide with demand. Wind turbines generate more energy at night when demand is lowest. To meet demand, a Smart Grid would not only switch from one generation source to another but also rely on demand-response – consumers changing their usage to different times of the day – and energy storage, often driven by price differentials.
Demand-response also plays a role in the use of plug-in hybrid electric vehicles. When recharging, these vehicles draw more electricity than a typical household, but their batteries can act as significant energy storage devices. Smart charging devices can be designed to communicate with utility companies and adjust recharging cycles to coincide with low prices, low grid impact and make use of low-emission periods – when renewable energy sources are available to recharge the vehicle. Dealing with surplus electricity is a concern with the present grid as electricity must be consumed the moment it is generated. Research is examining the benefits of distributed storage facilities that could decrease energy waste and make the grid system more efficient. Using two-way communication, consumers would be able to sell surplus electricity from wind turbines, roof-top solar panels or energy stored in plug-in electric vehicles, back to utility companies.