Ask a Techspert: How can we fight energy rush hours?

Then my neighborhood definitely created an energy rush hour this winter during the ice storm. So when everyone cranks their heat or A/C, what do the utility companies do?

 When demand for energy spikes, utility companies typically turn on additional power plants — which are often very expensive and emit a lot of carbon dioxide. And as more people need increasing amounts of energy in their homes and businesses, energy rush hours happen more frequently. We’ve seen several examples of brownouts recently — utilities didn’t have enough power to supply everyone, so they had to shut off power in certain places. As extreme weather events become more common this could happen more regularly, so utilities are considering building more power plants, which is costly and could increase carbon emissions.

But it doesn’t have to be that way! Utilities can incentivize customers to use less energy.

How? I can’t imagine not blasting my heat when it was so cold. 

Nest’s Rush Hour Rewards is one way people automatically lower energy use during energy rush hours without being uncomfortable in their homes. Think about using GPS during a traffic jam: You’re sitting on the highway and it reroutes you to side roads to get around the gridlock. You reach the same destination, you just took a slightly different way. Rush Hour Rewards is like that: Nest reroutes your home’s energy usage during times of grid congestion, but you still reach your destination — which in this case is your comfort level.  

When you enroll in the program, your thermostat will use less energy during times of high demand, but you’ll stay comfortable. And you get rewarded by your utility company because they don’t have to fire up additional generators. That reward could come in the form of bill credits or a sent check. You may even be able to get an instant discount on a Nest Thermostat from your utility provider. Just search for your utility and “Nest Thermostat” to find discounts.

How many customers using Rush Hour Rewards does it take to offset a power plant?

It definitely depends on the scenario but here’s one example: There are lots of peaker plants — the kind of power plant a utility would bring online during an energy rush hour — that are 50 megawatts in size, which is equivalent to only 50,000 thermostats participating in an event. Most major sports arenas hold more people than that!

How does the Nest Thermostat know when an energy rush hour is coming up?

Your energy company, or sometimes another entity that manages your electric grid, monitors weather conditions and forecasts electricity demand. When they predict demand will be high, they call a rush hour. Rush hours can also happen during grid emergencies, like when power plants suddenly go offline due to mechanical failure or extreme weather.

Another fun fact is that virtual power plants help balance renewables like solar and wind on the grid. 

What’s a virtual power plant?

A virtual power plant is what’s created when a bunch of different sources — like home batteries and smart thermostats — come together to help the grid like a power plant would. Because energy output from these sources varies based on things like cloud cover and wind speed, “mini” energy rush hours occur more frequently when there isn’t quite enough energy supply to meet demand. People who participate in Rush Hour Rewards can help balance the grid demand with energy supply. 

How does the Nest thermostat know what temperature is enough to keep me warm or cool but also enough to make a difference during an energy rush hour? 

Your Nest thermostat is very smart! It learns from your use what temperatures keep you comfortable and will make slight adjustments to those settings during or even before rush hours. For example, Nest may pre-cool your house a little bit before a rush hour event starts so that it runs less A/C during the rush hour. Same goes for pre-heating.

Right now, only thermostats participate in rush hours, but in the future your electric vehicle or even your whole home may be able to join in.