The advantages of demand side management when it comes to electricity use

Demand side management

It’s not easy running an electrical utility.

Electric utilities have to be able to meet the demand every minute of the day, no matter how much electricity we use. To make sure electricity is available around the clock utilities have peaking generators (often a natural gas plant) that they can fire up when demand is really high.

As you might expect, building a “just in case” power plant and leaving it idle most of the time is expensive and those expenses are passed on to consumers. Rather than unendingly increasing electricity, we could reduce power during peak times. That is called “demand side management.”

A dramatic example of demand side management was the emergency alert California sent to 27 million cell phones on Sept. 6, 2022. The message read, “Conserve energy now to protect public health and safety. Extreme heat is straining the state energy grid. Power interruptions may occur unless you take action. Turn off or reduce nonessential power if health allows, now until 9 p.m.”

The text went out at 5:45 p.m. and within 15 minutes electricity usage dropped by 2,000 megawatts, averting rolling blackouts.

A more sophisticated demand side management system leverages the power of large numbers. In the worst case scenario, high demand can trigger blackouts where a small number of customers have no electricity. Utilities can achieve the same reduction by making small (often unnoticeable) adjustments for hundreds of thousands of customers.

BC Hydro has a “Peak Rewards” program and Fortis BC is running a pilot program called “Peak Saver.” Customers can voluntarily join these plans by installing a special thermostat. During peak periods, the utility can make small adjustments to your heating or cooling. Customers can opt-out on any day by simply going to the thermostat and adjusting the temperature. Peak programs in California, where peak usage is tied to summer air conditioning, are more sophisticated. They pre-cool the house, then turn the AC on and off in short bursts.

Let’s look at two appliances -- your dishwasher and your home electrical vehicle (EV) charging station. Your dishwasher already has a four-hour delay setting. Because most people run their dishwasher after dinner, using the delay insures you have hot water (for the kids’ baths), puts off the dishwasher noise and moves electricity use from peak hours (4 p.m. to 9 p.m.) to off-peak hours (after 9 p.m.).

Home EV charging puts new pressure on the electrical grid. It’s natural to come home from work around 6 p.m., pull your car into the garage and plug it in. If you do that, you are drawing a lot of electricity during peak demand. Delaying the start time can be done by the user (some charging stations offer a dishwasher-like delay) or the BC Hydro and Fortis BC (non-peak usage savings) programs can communicate with your EV charger.

As battery storage gets less expensive, home battery storage systems can play a part in demand side management. One of the more popular home battery systems is the Tesla Powerwall.

It was originally a solution for homeowners with solar systems that produced excess power during daylight hours. Saving that electricity during the day and discharging it overnight allowed people to make maximum use of their solar capability. Conveniently, having a home battery system also provides power during an outage. With a utility-connected smart thermostat ,a collection of home battery systems can create a virtual power plant, replacing a fossil fuel peaking plant.

Where does demand side management fit into your life? First, be aware that peak electrical use happens between 4 p.m. and 9 p.m. Electricity used during those hours is more expensive and generates more carbon emissions as natural gas peaking plants are brought into use.

You can help avoid “dirty” energy by doubling down on normal conservation measures (putting on a sweater, turning off lights) and by shifting your energy intensive activities (like running the dishwasher and drying clothes) outside the 4 p.m. to 9 p.m. window.

If you install a home EV charger, choose a brand that has a delay setting. Consider participating in your utility’s new tariff plans—either a smart thermostat on a “peaking” tariff or a time-of-use tariff.

What matters is not just how much electricity you use, it’s also what time it is when you flip the switch.

This article is written by or on behalf of an outsourced columnist and does not necessarily reflect the views of Castanet.

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About the Author

Kristy Dyer has worked in the sustainability field for more than 10 years, including work with solar energy in New Mexico and cleantech in Silicon Valley. After she moved to the Okanagan, she ran a small business, Teaspoon Energy, doing energy audits of large houses. Most recently, she worked for a B.C. business doing carbon footprints for tourism organizations.

She has written about sustainability since 2012. You can find her columns archived at TeaspoonEnergy.blogspot.com.

Dyer has a background in physics and astronomy, and has occasionally been caught trying to impersonate an engineer.

A long-time member of First Things First, Penticton’s local climate change group, whose goals are to educate and lobby for solutions to the climate crisis, Dyer is honoured to live, work and play in the unceded, ancestral and traditional territory of the Syilx Okanagan Nation.

You can contact her at [email protected]

The views expressed are strictly those of the author and not necessarily those of Castanet. Castanet does not warrant the contents.

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