Meeting Demand for Electricity
By turning on the living room lights or a kitchen appliance, the demand created for electricity joins the needs of thousands of users across the province at that particular moment. The demand is first recognized by Hydro's System Operators in the Energy Control Centre (ECC), who schedule generating units to turn on to supply the electricity to homes and businesses across the province.
Electricity must be produced at the instant it is demanded. System Operators in the ECC manage how much energy is produced from many different generating stations, while monitoring current power demands and anticipating changes in customers' electricity consumption.
Supply and Demand
Electricity demand on the provincial electricity system falls into two categories – base and peak load. Base load is the continuous amount of electricity Hydro must supply at all times to meet every day demands.
Peak load occurs at the high points of demand during a day, season or year. The yearly peak often occurs between 5 and 6 p.m. on a cold and windy evening during the December to March period. The peak happens at this time because the weather is cold, people are coming home at the end of the day to turn on the heat, cook supper and watch television.
Some electricity customers, such as large industries, need a steady amount of electricity delivered throughout each day. Others need a large amount delivered at once. The total amount of electricity that Hydro can supply over a period of time is referred to as energy, and the highest level of electricity that Hydro can supply at any one time is referred to as capacity. Hydro must ensure it has sufficient capacity available meet peak demand and sufficient energy available to meet demand for electricity over a period of time.
For residential customers, demand for electricity starts the minute people get up in the morning and turn on the lights, run the shower and cook breakfast. At the end of each evening, the consumption of electricity subsides as appliances and lights are turned off and the heat is turned down. Throughout the day, demand for electricity is constantly changing and rises and falls depending on a number of factors, including the outside air temperature, wind, sunlight and people's behaviours.
Click here to view a chart that compares daily electricity consumption in the summer versus the winter in Newfoundland and Labrador.
Electricity cannot be stored for a rainy or snowy day – it must be generated and distributed as it is needed. For this reason, operators of Hydro's ECC must anticipate demands and schedule generation to meet that demand as precisely as possible. Likewise, they must foresee periods of low usage – the wee hours of the night, for instance – and reduce production to avoid wasting resources. This is probably not obvious when simply flicking on a household light switch. Yes, the electricity is there when it's needed, but that power isn't sitting still like gasoline in a fuel tank. The entire electricity system from the line in the living room wall to the complex grid that supplies it to the turbine that generates it is alive and pulsing with power.
Hydro also engages in system planning every year to ensure our existing and new electricity infrastructure can meet current and future demand for electricity. A priority for Hydro is to encourage Newfoundlanders and Labradorians to use energy wisely. Visit takechargenl.ca to learn more about how you can conserve energy and save money on your electricity bill!