We all know that renewable energy is the future. But recently something interesting happened: the future arrived.
It’s not all the way here – we are still getting far too much energy from oil, gas, and even coal – but it is here. Wind, solar, and energy storage are no longer novelties that operate on the periphery of a creaky, 20th-century power system. Instead, all summer, they have been stabilizing the grid, meeting peak demand, and driving down costs for consumers.
Sustained summer heat is brutal for the grid. Air conditioner use spikes and demand spikes with it. In New England, peaks in summer demand are more than 20% higher than the peaks seen on our coldest winter days. At the same time, high temperatures make power plants, transmission lines, and distribution infrastructure less efficient and energy losses increase. As the climate warms, longer, hotter, and more frequent heat waves are a recipe for disaster and it is why grid operators across the country were preparing the public for the possibility of rolling brownouts and other power supply disruptions during heat waves this summer. Fortunately, we have avoided major power disruptions and renewable energy is a big part of the reason why.
The New England grip operator, ISO-NE, reports that solar energy was instrumental in meeting demand during this July’s prolonged heat wave. On its own, behind-the-meter solar, the solar electricity that is used on-site in real-time without ever traveling across the grid, reduced peak demand by close to 4,000 MW – more than 15% of the total demand! –day, after day, after day from July 19-24. This meant that instead of facing the demand levels predicted for high heat events, the ISO only saw demand associated with more typical summer weather, resulting in significant savings for consumers.
All this behind-the-meter solar obviously benefited the homeowners and businesses that were able to run their lights and air conditioners with zero-cost electricity, but it also benefited every ratepayer in New England. During peak periods electricity is generated by the most expensive– and dirtiest – power plants on the grid and costs for utilities, and their customers, jump. By keeping these plants on the sidelines, behind-the-meter solar helps keep rates down for everyone. And there are other benefits as well. Because behind-the-meter solar doesn’t have to travel across overheating distribution infrastructure and doesn’t congest already strained transmission systems, it helps alleviate the need for a host of infrastructure upgrades. A previous analysis by Synergy Energy Economics – sponsored by Renewable Energy Vermont, Vote Solar, and Clean Energy NH – found that when considering the grid, health, and environmental benefits of behind-the-meter solar comprehensively, it has saved New Englanders more than $180 million each year from 2014-2019. Since solar capacity has continued to grow and natural gas prices are surging, the saving this year will undoubtedly be even higher.
Simultaneously, cheaper, more effective batteries are providing similar benefits later in the day when the demand for power from the utilities is highest. (While electricity usage peaked at midday during the heat wave, behind-the-meter solar meant that the peak demand for electricity provided by utilities didn’t occur until early evening). Green Mountain Power has been an early innovator with battery storage and Vermonters are reaping the benefits of these innovations. During July’s heat wave, GMP reported that by utilizing batteries in customers’ homes and at their own solar facilities, the utility was able to save $1.2 million in electricity purchases from expensive – and environmentally harmful – peaking power plants.
Finally, load management – changes in when we use electricity – is also helping utilities manage the challenges posed by extreme heat and high electricity demand. Frequently, we have at least some flexibility about when we run many of our largest electricity drawing appliances. By altering when in the day we are using these devices, such as by running air conditioning earlier in the day before the peak demand to “pre-cool” our homes or by programming dishwashers to run or electric vehicles to charge later in the evening, we can lessen the strain on the grid with minimal disruption to our own convenience and comfort. Burlington Electric Department has been and leader in load management and through its “Defeat the Peak” program it encourages customers to change their energy usage patterns by donating a portion of the avoided electricity purchase costs that the program achieves to local charities. In July, this collaboration between BED and its customers resulted in a peak demand reduction equivalent to taking 445 homes off the grid. Increasingly, we will all be able to opt-in to automatic load management options that subtly and seamlessly tweak when some of our large devices are using power without even thinking about it.
This is the future, these are the piece of the puzzle: renewable energy, energy storage, and load management. With the passage of the Inflation Reduction Act, we are primed for big investments in renewable energy and related technologies. Studies estimate that these investments will save the average household $200 a year in lower energy bills and help cut greenhouse gas emissions by 40%. We are seeing the benefits now and they will only continue to grow as we ramp up our investments in these technologies and the future fully arrives.