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Cake day: July 30th, 2023

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  • You very much gloss over the whole “distribution” part. That is one of the main three segments of an electric grid (generation, transmission, distribution). Practical Engineering has some great content about how the grid works and addresses some of the problems renewables face in certain aspects iirc. I recommend giving it a watch or at least a background listen. His first video that is a good place to start, and the “which power plant does my electricity come from” with the lake analogy is also a good intro.

    https://youtube.com/playlist?list=PLTZM4MrZKfW-ftqKGSbO-DwDiOGqNmq53

    Having a DER system is great and all because the transmission system doesn’t have to be as highly loaded (thus increasing the total load a system can withstand), but you still need to be pretty connected for something like this to work - and like others have pointed out, that’s going to mean building a parallel grid (which the energy regulators won’t like if you get too big) or hooking into the existing grid (which probably already has DER management baked into the system if you contact your local power company).

    The grid works because it’s big. That’s a feature, not a bug. And because we have AC not DC on the wire, any energized and connected generator has to be in dead lockstep with the grid frequency or else your hardware is going to become a load, make expensive noises, emit magic smoke, or some combination thereof.

    One major edge case you have is night charging of EVs. Let’s say I’m a 9-5 office worker with a standard parking lot at my workplace. I’m just a keyboard monkey doing whatever, so I’m not a decision maker as to what goes in the parking lot infrastructure wise, so I’m at the mercy of whatever Facilities is doing, and gods know what that is. But I have a nice brand new EV, and I want to charge it. When I drive home after DST ends, it’s dark outside. There’s no solar to charge my car. Some renewables (like wind and hydro) work at night, but solar doesn’t. I’d need to charge an auxillary power storage system during the day, and then transfer that to my EV battery at night. That’s more complexity.

    Power storage of any kind of generation is a huge issue with many different solutions, and not all of them are batteries. And nothing is a perfect system, so there’s energy losses whenever we convert from type A to type B of whatever.

    Or… I could just hook my EV up to the grid where the cost of my bill per kilowatt hour includes systems and people to manage keeping the system on voltage and on frequency, 24/7/365.25.

    Any power produced during that day for a solar system that doesn’t get immediately used needs to be stored (because it HAS to get put somewhere or you literally break the grid or waste it). That energy storage - along with the voltage converters - is going to take up extra cubic footage in your system that won’t be small, and requires regular monitoring and maintenance to stay online. The system you’re proposing is going to create many fragments of the grid in the form of these pop up neighborhood charging stations entirely dependent on what resources are available in less than a mile radius.

    Even if you assume that you don’t have to frequency synchronize with the main grid and you’re fully isolated, you run into another big problem: local generation isn’t always perfect. Solar especially is very susceptible to the giant orb in the sky being around, so your local energy storage needs to account for being able to hold enough power for a certain percentage above your worst case cloudy day while maintaining the necessary output to sustain the local EVs depending on it. If you get a 2- or 3- day storm, I hope you have enough energy storage to have low daytime charge rates for 4- to 5- days. In the playlist, there’s also a video talking about using hydroelectric generators in reverse to store energy as physical potential energy in a reservoir as one example of how a grid might store excess energy.

    This is one thing the major grids are quite literally engineered and regulated to accomplish: because they are in fact so large, they can just import energy via the market system from somewhere with better weather or is slightly off-peak demand. And when one type of energy becomes less viable for a given weather condition (like solar on a cloudy day) they have a diversified generation portfolio of other sources: renewables like wind and hydro, nuclear energy for big orders, and even grid-scale energy storage system such as flywheels (fast stabilization), pumped water storage, and even giant batteries, and if all those fail, well yes we do still have dinosaurs to burn. (The world’s not perfect yet and we should by all means go for progress, but it will be a long road). And all these sources are already working together to keep the grids on voltage and on frequency, and have physical and managerial infrastructure to keep everything connected and synchronized such that supply and demand are balanced.