I love spring. I love unmuffling as I—and the world around me—shake off winter. I love flowers popping up, trees leafing out, birds singing their hearts out. And I love hearing about new renewable electricity records as spring unfolds.
A few recent examples for that last love: California scored a new record for total generation from renewable energy in mid-April and a new record for solar production in mid-May. New York just broke its solar record. Texas, which set nine new records for renewables generation from March through June last year, set a new one in April. That same month, New England recorded its lowest demand ever for electricity from the regional grid, which the grid operator attributed to record rooftop solar production. And there’s been plenty of proof that this spring-is-great phenomenon isn’t confined to the United States.
Here are three reasons why we keep seeing records like these in the spring, and why they’ll keep on coming.
1. Sun, wind and water
One obvious reason for strong spring performances is the seasonal abundance of sources that drive renewable energy generation.
For solar, spring brings longer days and luscious sunlight that not only wake up the flowers, trees and birds, but also ramp up generation from solar photovoltaic (PV) panels in fields and on rooftops. Spring also offers still-cooler temperatures than what will come in summer, providing an additional boost. (PV panels, like electronics in general, operate more efficiently with less heat.)
For wind, spring is also famously “a breezy, blossomy season,” as one of my kids’ favorite books, on seasons, talked about, and the data bear that out: While wind patterns vary by location and region, wind is strongest in spring for the country as a whole.
For hydropower, patterns vary by region, as with wind, and generation also depends on dam operators’ decisions about when to release water and when to store it for later generation. But April showers (bringing May flowers) and rainfall later in spring can combine with early melt from winter snowpack to boost hydropower, so spring tends to be the time when there’s the most hydro generation.
More sun, wind and water means more power from the three largest sources of renewable electricity in the country.
2. Between heating and cooling seasons
Headlines about renewable energy records also highlight how much of electricity demand renewables are meeting at a given time. Those numbers look better in spring not just because of stronger generation, but also because of changes to the “denominator”—the overall demand for electricity.
Spring tends to be a time when there is lower electricity demand. While that, too, varies by region (and I know the cold stuck around for longer than usual in my part of the country this year), households generally turn down their furnaces and heat pumps, and they haven’t yet turned on their fans and air conditioners in full. That means that any renewable energy generation will supply a larger portion of demand.
That lower-than-expected electricity demand also makes spring (and the other “shoulder” season, fall) the go-to seasons for fossil fuel and nuclear power plants to go offline for scheduled maintenance—or refueling, in the case of the nuclear plants. That means that there are fewer of them competing to supply demand. While solar, wind and hydro win on price (their marginal cost is zero), they sometimes get pushed out of the market, or “curtailed,” when demand is lower. That’s due in part to coal plants’ inflexibility for reducing their output. A 2021 Union of Concerned Scientists-commissioned analysis found that that kind of inflexibility led ratepayers in the Southwest region of the country to pay an extra $40 million per year because utilities curtailed wind to make way for more expensive (and dirty) coal power.
3. Reaping harvests from a year of growth
The biggest factor behind renewable energy records in the spring, though, is new renewable energy installations. New records are a direct result of the new renewables—solar and wind, in particular—built over the previous year. Solar and wind generation grew by an average of 16 percent a year over the past decade and was 18 percent higher in 2022 than in 2021.
Growth in US renewable energy capacity last year alone set the stage for new records this spring. Solar capacity grew by almost 17 percent, while wind capacity finished the year more than 6 percent higher than in 2021.
How climate change plays a role
One of the reasons to be so excited about tangible renewables progress is its implications for addressing climate change. The more renewables grow, the more we can move away from fossil fuels and reduce their emissions to stop making the climate problem worse—as well as roll back their threat to public health.
Climate change, however, also has implications for renewables—including in spring—as the summer Danger Season gets longer and longer, extending into the shoulder season. Along with being affected by extra heat (as most power generation is), PV panels can be undermined by extra smoke and soot from wildfires. Climate change is altering wind patterns in various ways, and whether wind speeds (and therefore wind production) increase or decrease may vary by region. Hydropower in spring can be affected by changes in snowpack, changes in the timing of its melt, and changes in spring rainfall. Climate change also affects electricity demand, with increased periods of extreme heat or cold when we don’t expect them.
More renewables, not less
None of those realities of climate change are reasons to focus less on renewable energy and new renewable electricity records, especially in light of the wide array of fossil fuel power plants’ own vulnerabilities to climate change and extreme weather. Indeed, they are good reasons to focus even more. Noting, and celebrating, new records is a good way to remind everyone of our progress in our transition to clean energy, and to motivate everyone to do a whole lot more. And those new records are yet another reason to love springtime.