Skip to main content

Where is the Power Going

In this episode, Where is the Power Going? . . .



Have you ever wondered where the electricity generated by a PhotoVoltaic (PV) Solar system goes when the system is shut down? Stay tuned for the answer.


On Thursday, February 16, 2023, about 22 attendees from the Cenergy Power staff attended a carport system project tour of a One MegaWatt-DC (1MW-DC) PV solar array at Long Beach Memorial Hospital, in Long Beach, CA. hosted by Eilroma Sarkis, Cenergy's Project Manager. For many, this was the first time visiting a commercial solar installation. As expected, there were a lot of questions from the guests.


To get an idea of the scale of this project, each carport section spans about 45 feet in width and is 200 feet long. There are five such arrays. The tour lasted about one hour; our host explained every aspect of system construction; module layout, system orientation, electrical components, wiring, inverters, shutdown panel boards, interconnection to the hospitals' main electrical service, system monitoring, electrical grounding, and much more. Click the YouTube link to view a few attendees' photos, reactions, and comments.


However, one nagging question kept coming to my mind: "We are standing under a connected 648.72 kW-DC PV Solar Array that is generating DC Power. The system is turned off. Where is the electricity being generated by the modules going?


After discussions with one of our electrical engineers and studying a few physics videos on YouTube, I was reminded that PV solar modules are passive devices. This means the over 1,224 - 530 Watt PV modules only produce a current (electrical flow) when connected to a load. Translation; A load occurs when Power is requested by lighting in the hospital, air conditioning, possible battery storage, or any other on-demand electricity requirements.


Since this system's inverters were turned off, this is considered an open circuit. The 10-50kW string inverters were not fulfilling the demand for a load. Therefore no power (voltage x current) was generated by the system.


However, another fundamental principle applies, the "Conservation of Energy." During a shutdown, the modules will continue to convert sunlight into DC electricity. The electricity generated by the PV modules will dissipate as heat.


The system will simply "idle" until turned on, then the inverters convert the DC electricity into AC electricity that can be used or stored. It's important to note that even when a PV solar system is turned off, there can still be some residual voltage, which can be dangerous. Therefore, it's necessary to follow proper safety procedures when working on or around a PV solar system, even when it is turned off.


Now you know the rest of the story!


I'm Patrick Ball; thanks for listening. See you in the next episode.

Comments

Most Popular of All Time

Paris – the End of Silence

✈️  In this special episode: Paris – the End of Silence Sometimes, connection arrives in the most unexpected form—not through grand gestures, but through a quiet voice carried by technology. In a Paris apartment, I finally understood my family’s words . . . and felt my mother’s presence in every sentence. Since I was a little boy, France has been both a beautiful and frustrating paradox in my life. Every six to nine years, my mother, Mauricette, would take my brothers and me back to La Rochelle to visit our French family. The moment we arrived, the air would fill with a sound I loved but couldn’t share in—the rapid-fire, musical rhythm of French. My aunts, uncles, and cousins would warmly sweep me into hugs and kisses, their words flowing like a lovely melody I couldn’t quite catch. I’d smile brightly, trying to communicate with my eyes and hands. But as soon as we stepped off the plane, my mother and her sister-in-law, Joséan, started talking animatedly. They were gone, chatting h...

Pushing the Pause Button

In this episode, Pushing the Pause Button: Stepping Off the Treadmill Hello, friends — If you're reading this, I'm already off the grid. Today begins a much-needed vacation, and for the next few weeks, On the Fly is taking a break right along with me. For a long time, my inner voice has said, 'Keep every commitment, no matter what.' That's meant early mornings, long days, and a calendar packed with posts, podcasts, and projects I couldn't seem to say no to. I've been trying to be the tireless workhorse—but that kind of grind doesn't end well. Lately, I've noticed I'm not quite myself—shorter fuse, louder sighs, and a few too many grumbles (Lori deserves a medal). That's when you know it's time to hit pause before the spark burns out. So, I'm stepping back to rest, recharge, and remember what it feels like to not live by the next deadline: no tech, no to-do lists, just some space to breathe. Thank you, truly, for all your support and ...

Noirmoutier: An Ocean Between Us, Gone in a Moment

In this episode, Noirmoutier: An Ocean Between Us, Gone in a Moment. Sometimes love waits half a century for its moment — and when it finally arrives, time doesn’t stand still; it disappears. The moment I stepped off the train in Nantes, it felt like time froze. There she was — my cousin Michèle — waiting on the platform, arms waving desperately. When we finally embraced, the fifty years that had passed between us disappeared in an instant. The melody in her voice was the same, but softer than I remembered. We both shed tears of joy that only come from love long overdue. “I’m so happy you are here,” she whispered, her voice trembling.   Thank goodness for the translation app on my phone, because the conversation began immediately — fast, fluid, and unstoppable. The Frenzy of Catching Up As we drove for about an hour to the tiny town of L’Épine on the Island of Noirmoutier, the words kept tumbling out. Michèle and her husband, Alain, are the most gracious hosts — but my new challe...

Our Journey to Avignon

🇫🇷 Lost in Transition: Our Journey to Avignon (Part 1) When everything that can go wrong—does—sometimes grace still finds you. Our Monday morning trip began on the quiet island of Noirmoutier , where salt marshes and sea breezes whisper of simpler days. From there, our early morning drive was uneventful; we arrived at the Nantes station with plenty of time to spare. From Nantes to Paris Montparnasse, everything went smoothly—so we thought, until it didn't. That's when things started to unravel. If you've never traveled the Paris Metro , imagine a vast underground maze pulsing beneath the city—corridors twisting into one another, trains roaring in and out of the dark, staircases that rise and fall like riddles. It's efficient, yes—but only if you know where you're going. We had over an hour and a half to make our next train to Avignon —plenty of time. Or so we believed. We needed to reach the Gare de Lyon station, where our TGV (high-speed train) was headed south...