Xcel customers lost control of Smart Thermostats

Xcel, a utility company, locked thousands of customers out of their intelligent thermostats in Colorado, which left customers sweltering in a heat spell stressing the grid.

Thousands of Colorado locals were locked out of their intelligent thermostats during sweltering temperatures last week to prevent power demand from overwhelming the grid.

About 22,000 Xcel customers lost their smart thermostats for hours on August 30th. That led to backlash on social media as some said the temperatures inside their homes reached as high as 88 degrees Fahrenheit. In addition, outdoor temperatures climbed into the 90s that day across parts of Colorado as much of the western US grappled with sweltering heat.

All the customers affected had enrolled in an energy-saving program called AC Rewards, meant to ease the strain on the power grid during heatwaves. Xcel can adjust those customers’ smart thermostats when demand gets so high that there might not be enough supply to meet it. Xcel offers a one-time $100 credit on electricity bills upon signing up and $25 a year afterward for participation.

When the utility adjusts a customer’s thermostat, the customer typically has the option to opt out. But, “On rare occasions, system emergencies may cause a control event that cannot be overridden,” the company says on its website.

Xcel Energy Inc., an American utility holding corporation, is based in Minneapolis, Minnesota, serving around 3.7 million electric clients and 2.1 million natural gas consumers in Colorado, Texas, and New Mexico. It holds four operating subsidiaries: Northern States Power-Wisconsin, Public Service Company of Colorado, Northern States Power-Minnesota, and Southwestern Public Service Co.

Xcel Energy announced in December 2018 that it would deliver 100 percent carbon-free clean electricity by 2050, with an 80% carbon drop by 2035 (from 2005 levels). It makes Xcel the first major US utility to set such a goal.

Last week was the first time Xcel barred customers from overriding their adjustments in the six years since the program started. High temperatures, soaring power demand for air conditioners, and an unexpected outage contributed to last week’s energy emergency, Xcel vice president Emmett Romine told Denver7. Xcel did not immediately respond to a press inquiry from The Verge.

Extreme heat stresses power grids across much of the Western US during a prolonged heatwave that started last week and is expected to linger well into this week. As a result, California’s grid operator has urged residents to conserve energy over the next several days to avoid blackouts.

Americans are facing growing power interruptions compared to the past, partly because of more extreme weather. For example, 2020 was a record year for power outages in the US. Last year, residents’ punishing summer heat in Texas triggered a similar backlash when utilities set customers’ smart thermostats to higher temperatures to limit power demand.

Such programs are part of a demand response strategy to help power grids become more resilient to extreme weather circumstances that are becoming more regular and intense as global temperatures rise. Energy providers are constantly managing a precarious balance between supply and demand that can quickly lead to power outages during demand peaks. Demand response can smooth out those peaks, which typically spike when heatwaves drive up demand for electricity to power air conditioning. So while some customers might see their thermostats set to higher temperatures than anticipated, that’s supposed to help power stay on for their households and neighbors.

However, that strategy has a risk if smart thermostats keep homes at dangerously high temperatures. Prolonged vulnerability to high temperatures — especially at night when individuals are at home sleeping — can direct to heat-related illness and even sudden demise. Heat spells kill more people in the US than any other weather-related disaster.