On Monday, April 8^th, parts of the U.S. will experience a total solar eclipse. The last total solar eclipse was in 2017, and before that it was in 1979. While partial eclipses are more common, and can happen globally, after Monday, there won’t be another total eclipse until 2045.

For most, a solar eclipse is a unique day to break out the eye-protection glasses and gaze up at the sky to see something that will only happen a few times in their lifetime. A small county in Texas is even gearing up to declare a state of emergency due to the high volume of tourists expected to travel to the area for a front row seat.

Disruption is expected for some businesses and individuals across the U.S. With the new energy mix – including solar – added to the grid daily, U.S. utilities and their customers could also be facing a power disruption when that sun suddenly goes away for a few minutes. But for those utilities that are already relying on intelligent digital systems to help plan for load balancing and real-time power-mix optimization, April 8^th won’t be much different from any other Monday. It’s unlikely there will be any disruption to U.S. power grids because utilities plan ahead and have the resources and capabilities to ensure a reliable grid.

 

Managing Intermittent Energy Resources

As the world makes progress toward net-zero in 2050, utilities have found themselves at the center of the energy transition. The integration of large-scale solar and wind farms as well as Distributed Energy Resources (DERs) on the grid, such as electric vehicles, roof-top solar and residential batteries, will become an important part of the energy transition the world is calling for. However, renewables are not without their operational challenges. Due to the intermittent nature of these resources – solar energy only produces when the sun shines, wind energy is only available when the wind blows – utilities are facing a challenge to balance power supply against load demand when they can’t guarantee power production.

In prior years, it’s unlikely a rare solar eclipse would have posed a threat to grid reliability because solar power was such a small percentage of the overall power generation mix.  However, the unprecedented adoption of renewables has established solar as a sizable portion of overall power generation in regions and a disruption, even for a few minutes, could cause catastrophic grid-wide failure if not planned and managed properly.

Today, grid operators and balancing authorities find themselves needing to prepare for everyday occurrences that could disrupt large-scale solar resources and the thousands of DERs connected to the grid. In the example of an eclipse, there could be a drastic drop in solar generation by as much as 10% during an uncommon time of day, followed by a sudden generation spike when the sun comes back, all over the course of 1-2 hours. capacity replacement, increasingly new cleaner solutions like Energy Storage Resources, i.e., fast responding batteries, can supplement sudden capacity dips and peaks to balance the grid. 

Whether a solar eclipse or another event, managing intermittence and volatility on the grid calls for forecasting and planning. Changes to energy supply need to be managed, both in advance and in real-time. This includes renewable generation forecasting, day-ahead capacity planning and real-time generation control. Intelligent automation and digital technology allows utilities to better integrate both largescale resources and DERs into the energy landscape, without sacrificing reliability.

While solar eclipses are rare, and it’s unlikely there will be any disruption to U.S. power grids on Monday, they represent an example of the challenges utilities are facing when operating unpredictable renewable energy on the grid. The clean energy transition is transforming supply and demand dynamics and the resulting decentralization and bi-directional flow creates new challenges for utility stakeholders. Digital solutions enable an intelligent power grid equipped to handle variability due to extreme weather events, regardless of how common they are.