Photo Credit: NASA

Solar eclipse – what happens to solar power?


By: Alyssa Pek, Communications Assistant

On 21 August, everyone in the US had their eyes to the sky as they witnessed a coast-to-coast total solar eclipse for the first time since 1918. While this astronomical event, dubbed the ‘great American eclipse’, was creating buzz globally, another topic was making headlines in the weeks leading up to the eclipse  – what would happen to solar power?

As the path of the eclipse was crossing solar-heavy states such as California and North Carolina, many were worried that this would destabilize the grid as it would be cut off from one of its key energy sources.

Despite these fears, the US breezed through this stress test on its energy supply exceedingly well, with the grid suffering only minor fluctuations.

Although solar generation declined during the time of the eclipse, so too did energy demand.

As masses of the American population were distracted by the eclipse itself, they did not consume as much energy as they typically would on a Monday morning. Furthermore, public service announcements, especially in California, asking citizens to reduce their energy consumption during the time of the eclipse contributed to the overall decrease. This was a major factor in easing the pressure on the grid and softening the blows of energy price hikes throughout the event. Utilities therefore did not need to make as many calls on other power sources to replace solar as was predicted.

The hype of the ‘great American eclipse’ ultimately resulted in just another day at the office for utility providers in the US.

Europe experienced a similar stress test with their own total eclipse in March 2015.

This was the first time that a total eclipse had appeared over a region with major PV capacity, and TSOs in Europe prepared for over a year in the lead up to the event. A pan-European teleconference, training and doubling staff during the eclipse as well as scheduling maintenance operations to different times so that the grid would be working at its maximum potential were all factors which contributed to the successful energy management and allowed Europe to be kept switched on throughout the entirety of the 3-hour eclipse.

However, as solar becomes a bigger part of the energy market, it will be essential to create smart solutions to ensure the stability of the energy market for events like this in the future.

Regional cooperation is key to smoothing instabilities on the energy grid. As not every region will be effected the same by a particular event, the spreading out of renewable energy over a greater geographical area can help to better mitigate interruptions on the grid. Electricity policy and TSOs must be better coordinated so to better balance energy supply and demand in a region.

This can be further facilitated through the smartening of grids to accommodate system services by PV. One of the most effective ways to do this is through the adoption and implementation of network code. Demand Connection Code (DCC), Capacity Allocation and Congestion management (CACM) and the Requirement for Generators (RfG), are all examples of how energy management can be better facilitated.

However, not all regions are alike in terms of climate, energy consumption habits and installed capacity. It is therefore extremely important to gather extensive data and have a clear picture of the region impacted by an event such as a solar eclipse in order to effectively manage any interruptions.

What will be important in the years to come is to increase international communication and awareness regarding the importance of creating a smarter and more efficient energy system which can better manage the impact of solar eclipses in the future.

While the sun may have been blacked out that Monday morning, solar’s future in the energy system continued to shine bright.