Where Does Grounded Electricity Actually Go?

Grounding is one of the most confusing and misunderstood aspects of the grid.

Errata:
At 10:40, the meter is set to resistance (not voltage). Since current is constant, it is also an indication of differences in voltage, but the script should have been a little clearer.

Current doesn’t flow to the ground; it flows through the ground and back up. If there is electricity moving into the ground from an energized conductor, go back to the source of that conductor and see what’s happening. For the grid, it’s probably a transformer or electrical generator, in either case, a simple coil of wire. And, the electrical current flowing out of the coil has to be equal to the electrical current flowing into it, whether that current is coming from one of the other phases, a neutral line, or an electrode buried in the ground.

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This is not engineering advice. Everything here is for informational and entertainment purposes only. Contact an engineer licensed to practice in your area if you need professional advice or services. All non-licensed clips used for fair use commentary, criticism, and educational purposes.

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This video is sponsored by HelloFresh.
Stock video and imagery provided by Getty Images, Shutterstock, and Videoblocks.
Tonic and Energy by Elexive is licensed under a Creative Commons Attribution License
Video by Grady Hillhouse
Edited by Wesley Crump
Written and Produced by Ralph Crewe
Production Assistance from Josh Lorenz
Graphics by Nebula Studios

[Adam]

@Practical Engineering: at approx 19:30 you mention hopping to limit the chance of step potential - this is no longer the case, at least in the Australian electricity industry. The reason is that a person hopping (one or 2 footed) is very prone to overbalance and accidentelly step or fall, thereby creating the step potential and possibly injuring themeselves as well.
Current training is to keep both feet together and 'shuffle' by sliding one foot forward no more than 3/4 of the length of the foot so they stay together, then shifting the other foot in the same manner. In this way, while some 'step potential' will potentially still exist it will be small, and the feet / ankles / legs touching provides a path for any currect without transitting through the torso.
Another thing to note is to avoid any sudden ground condition changes where possible - don't move from dry ground to wet, concrete to grass, etc.
Great content!

[zzzz]

I am an electrical engineer (in the US) that designs the grounding grids for substations to limit touch and step potentials. I can confirm that there are tons of calculations & analyses that go into the design, including simulations of worst case faults to make sure there is a near zero chance of injury. However, ground grids are not designed to eliminate potentials, only to reduce it enough to prevent arrhythmia. So if you happen to be at a substation during a ground fault, you may still get zapped, but it won't be fatal!

Great video Grady!

[FanZ]

I never felt like the concept of electrical ground was very well explained in any of my electronics or physics classes; and I still don't feel like I totally understand it, but this video helped at least a little bit, so thanks!

[ElectroBOOM]

Well done! You stepped in my territory, and you managed to survive! 😁

[rhouser]

When I started at the power plant, I asked about where all it fed power to. A guy told me it’s pretty much like throwing a cup of water in a stream & someone else pulling a cup of water out down stream. Yea it could’ve been your water, but more than likely, it was a combo of all the tributaries.

[BluesMan]

As an electrician I see a lot of apprentices get confused with grounding, grounded and bonding. In school and generally out in the world we hear a lot of "electricity wants to flow to ground" without really understanding whats happening. Easiest way I explain it, electricity doesn't want to flow to ground, it wants to return to the source, through the ground, in a grounded and properly bonded system.

[NialllennoN]

I work at an insurance company, and a major fire loss came in where the client had installed an electric fence on their balcony to ward off pigeons/birds, and it required grounding.

They put the wire into a plant pot on their balcony.

[Danger_mouse]

13:00 Grady, fun fact.
The early telegraph system in outback Australia used a single wire system as the iron ore content in the soil was high enough to use as the earth return.
It's what gives the outback the classic red/orange colour.

[michaelcarr]

I'm in charge of a power transmission grid and always enjoy your videos. The accuracy of the information makes me trust your videos on topics for which I'm not an expert. Your channel is a gift to the world.

[javersongoulartfilho]

As a chemist I'm used to deal with elements exchanging electrons to make things happen, but when it comes to electricity in a circuit & insulation I'm as a smart as a wood door, save from battery cells. Thanks for sharing this with us.

[johnstreet]

Grady you do a fantastic job of education and explanation of your subjects. I lived in Cambodia which has a 220/380V or so system. Each house was connected to one hot leg of a 3 wire wye and the common. Common was NOT grounded. Middle of the night one phase was 280, in the heat of the day with all the air con running it was 160 or so. Across the street was a welding shop which was on a different hot leg of the wye. I has incandescent lights in my bathrooms, and whenever he struck an arc it would drag the common towards him and increase the brightness of my lamps A LOT. I finally replaced those fixtures with electronic ballast fluorescents, which eliminated the change in luminance. Some fluorescent light switches in the house broke the common instead of the hot, so the input capacitor in the ballast would charge and then flash the lamp about every 5 minutes. Interesting experience living there.

[Zephyr]

In the Navy even though it can be more dangerous, we often use ungrounded 3 phase distribution systems so that they continue operating even in the event of a ground fault (like a missile blows a hole in the side of the ship)

[alexanderthomas]

Great video. Despite having a degree in electrical engineering for 21 years, this is the first time someone completely explains the concept of ‘ground’ in all its aspects in one single go.

[stephenalexander]

I worked as a journeyman lineman for 36 years. I have found your videos to be interesting and accurate. I think your comment about electricity following all the paths available is very important. Many have been killed thinking the the path of least resistance. I started in 72 and the rule then was to work "between grounds.". Time went by and "singlepoint' grounding became a thing. Grounding from the conductors to the tower or pole below the linemans feet making for no differential.
It was a hard sell, still might be, but it works.
Im going to watch this one a few more times to see if I can learn more.
I think you are one of a few people, who sre not in the electrical industry, who understand what goes on here.

[traildude]

I helped an electrician completely overhaul the electrical system at a large multi-building facility originally built in 1906. All the lines in on building were just single wires that ran the length of the building and at the far end connected to a steel pipe that ran along the top of the wall; that was the return line.
We made a bizarre discovery, though: the men's restroom in one corner of the building still had the old steel trough as a common urinal, which was bolted to a frame of steel pipe inside the wall. Somewhere in the decades between the original construction and the electrical overhaul, for some reason the steel pipe serving as the return electrical line had been cut and a section removed -- and when that section had been replaced it hadn't gotten connected back to the return line but instead to the steel frame for that trough urinal, and then a heavy wire had been run from that frame back to the main electrical panel. So for years, probably decades, that men's restroom had an electrified urinal.
BTW, the 'hot' wires were only insulated on about eight inches on either side of where they were attached to glass mounting insulators, and the wire insulation was just tar paper wrapped around the copper wire.

[kvg]

My electronics professor was explaining 3 phase, 4 wire motors. He had a diagram of the 3phase generator connected to the 3phase motor and kept emphasizing the “4 wire” part of it. Finally a student asked, “where is the fourth wire?” Then he pointed to the ground symbol and added a ground layer to the diagram connecting the generator and the motor.

[dustinsullivan]

Your tap water must be ridiculously good. At my high power lab, we would use city tap water as a salt water source when mixing into DI water to set water conductivity.

[FuncleChuck]

I like when ground is Earth. Grounding to the Moon is just so difficult.

[holysol]

it goes to its room to think about what its done, only then can it have dinner

[NoahSpurrier]

I remember working with a friend of mine on my home electrics. I mentioned to him that the circuit was live, so be careful. He said not to worry because he wasn’t grounded. He grabbed the hot wire and got a shock. I explained capacitive coupling with AC.