When did you decide to stay home this spring? Sense analyzed home energy data to discover when people stayed home and how much it impacted their costs.
With so many people at home this spring, we wondered about the impact of Covid-19 on home energy usage and turned to Sense home data to analyze changes across the country. In March and April, home energy usage increased substantially as more people stayed home. We also saw unexpected inflection points that show when people made the decision to stay home.
Our data indicates that the average home electrical usage increased 22% compared to 2019, a reflection of people using more electricity while they stayed home. With this increase, most consumers are paying 22% more on their April electricity bill compared to April 2019, with a typical increase of $22-$25, and higher in states with steeper utility rates.
Staying at Home Increased Electricity Demand and Costs
Ordinarily, home electricity demand decreases in the March through April time frame due to warmer weather in the spring (blue line in the graph). In 2020, instead of falling, daily electricity demand increased 22% from March 10 to April 10 (red line). Since weather is relatively temperate across most of the country in March and April, people can expect their costs to increase in the warmer months ahead as HVAC systems turn on to cool the air where people are still at home.
The Flattened Duck Curve
Mid-day energy usage was the biggest factor in driving up energy demand. Ordinarily, home energy usage drops in the middle of the day between 10 am and 4 pm, when many people are away from home for work or school. Utilities call this pattern the “duck curve.”
425 kWh compared to 2019 averages. This change in energy usage reflects that most people are home all day and using electricity. In other words, the home’s energy “duck curve” has flattened for most Americans.
When Did People Stay at Home?
Sense discovered intriguing patterns in energy data that show people’s responses to the Covid-19 epidemic. The data shows that most people made the decision to stay home soon after state emergencies were announced but well before state stay-at-home orders were issued. The biggest increases in home energy demand took place between March 10 and March 21, coinciding with work, school and college changes. As state governments ease restrictions in coming weeks, the Sense dataset points to multiple factors influencing peoples’ decisions to stay or leave home, including business and school policies.
The steep rise in energy demand as more people decided to stay home between March 10 and 21 coincides with a number of external events related to Covid response that took place before the states issued stay-at-home advisories.
• Between March 3 and 10, California, Massachusetts, New York and Ohio declared states of emergency.
• On March 10, Harvard and MIT sent their students home to learn online, followed quickly by many colleges around the country.
• On March 10, Facebook, Google, Twitter and Amazon asked employees to work from home.
• On March 11, the NBA suspended the rest of their season when a player was diagnosed with Covid-19.
• On March 13, the federal government declared a state of emergency.
• Starting on March 16, most states closed elementary and high schools.
California issued its stay-at-home advisory on March 19, followed by Ohio, New York and Massachusetts within 4 days; Arizona, North Carolina and Texas issued orders later in the month.
Based on these home energy trends, most Americans made their decision to stay home before being ordered to do so by the government. Other factors appeared to be influential, including actions by prominent businesses and colleges, the need to take care of school age children who were now at home, and emergency orders by states and the federal government.
The Sense home data revealed that after March 14, daily energy consumption increased 22.4% across the country, driven by a 35% increase in mid-day demand, but changes varied significantly across states. Interestingly, homes in North Carolina and Arizona increased at a rate that was half the national average, implying that fewer people stayed home in those states.
The governors of Arizona and North Carolina issued stay-at-home guidance on March 30, a week after most states. This later guidance may be a factor in residents’ decisions. After March 14, the average North Carolina home’s daily consumption rose by 9.6%, and the average Arizona home’s daily consumption rose by 8.6%, indicating that fewer homeowners were at home during the day compared to national averages.
Sense analyzed data for 5000 homes that have the Sense Home Energy Monitor across 30 states that are geographically representative of the country . The analysis identified percentage increases in home energy demand compared to the same dates in 2019 and normalized for weather. Duck curve data was analyzed for the period March 20-30 when home energy demand was at high levels.
Download Sense’s report, which includes additional state-by-state charts.