Electric Shocks Under Pylons

[KnackeredBike]

I've always wondered if you are at risk cycling through an area with low surrounds in a lightening storm, as you would seem to make a perfunctory lightening rod. A very dramatic ride, nonetheless.

 

[classic33]

I've always wondered if you are at risk cycling through an area with low surrounds in a lightening storm, as you would seem to make a perfunctory lightening rod. A very dramatic ride, nonetheless.

They can be fun though.

 

[swansonj]

Morning all,

As I commute home on an evening, I cycle under an electric line that is held up by pylons either side of the road at a height of (a guess) 10-15m, and quite a few times now I've experienced a static type shock.

At first, I was cycling with my hands on the rubber grips and my thumb was close but not touching the metal frame of the bike - and I felt a sharp pain in the thumb knuckle and heard a click/buzz. I thought perhaps a bee had bounced off.
A few days later, the same happened.

I then started cycling with my whole hand well onto the grips and away from the frame, and two nights in a row now, at the same spot, I've felt the shocks all over, particularly in the sit bones on the saddle.

A quick bit of Googling tells me to cycle with something in contact with the metal frame and so stopping the charge from building up. My anecdotal evidence from moving my thumb away from the frame and things getting worse suggests this might help. However, what I don't get, is why this works at all - if I cycling along on two rubber tyres then touching the bike should make no difference as the bike isn't grounded?

Anyone else experience this? What do you do? Should I be worried?

I don't know where Google took you but the original (and, in my humble opinion, though I may be biased because I wrote it , the most comprehensive) explanation is this:
http://www.emfs.info/effects/microshocks/microshocks-from-bicycles/

The bicycle can indeed be electrically isolated from the road but what matters for this phenomenon is any difference of potential between rider and bike, not between either of them and the road.

View attachment 360473

Click on this to link to a video.

Fluorescent lights can light up in the electric field under a power line. But that's not too surprising- their whole means of operation is to convert an electric field to light, that's how they are designed. But they start producing visible light at around 0.1 milliamperes, and humans tend not to sense anything until several milliamperes. When you hold one of those tubes lighting up under a line, you don't feel a thing. In fact you can do the same thing with static electricity- hold one end of the tube and rub your foot on a nylon carpet...

Carbon is conductive though.

I've never measured exactly how conducting a carbon bike is. If anyone fancies providing the bike, I'll provide the power line....

You are being shocked by induction. You've become the secondary coil on a transformer.

Now is not the time for a Brooks saddle with rivets. Trust me on that one.

Yes to the rivets on a saddle being one of the places where these sparks can occur. But not really to this being to do with transformers - transformers are to do with magnetic fields not electric fields.

Blimey.

I had no idea that cycling can turn you into a human Van-Der-Graaf generator.

I need to be particularly careful having a defib/pacemaker.

Serious comment: this phenomenon of sparks while cycling under a power line (or while carrying an umbrella or touching a metal gate) won't affect an implanted medical device - the energy is too low (you feel it only because it's concentrated on one small point of skin, and once it's spread out inside the body, it generally becomes negligible). Nor should the direct exposure from walking under even the lowest power lines affect a pacemaker, the immunity standards ensure that, and there is not a single instance on record of a person in the U.K. experiencing interference from a power line. Inside a substation or a power station it could be a different matter, and I'm sure you've been warned about some shop security devices, some DIY power tools, etc; but you're OK with power lines.

As you may have gathered, this is my day job, and forum joking aside, I'm delighted to answer questions...

 

[classic33]

[QUOTE 4871813, member: 9609"]never had any shocks cycling under these monstrosities but I always find them a bit inrtimidating, one set I often go under, they seem lower than usual and the buzzing and crackling noise seems extra loud and intense. Just don't like them at all, blots on the landscape the lot of them.

I can't find it on the internet but I'm sure I read once of someone with powerlines going over his house, he built a shed under the lines, put a large lump of iron in the shed and wound copper round and round it, I suppose like a secondrty coil. Apparenrtly he done well out of it and was only caught out by the electric company when he showed off about his clever idea. Think he got an even bigger fine and lost his job for nicking the copper from his work[/QUOTE]
This sort of thing?
Energy refers to the amount of work that a system can perform. According to this definition free energy is a logical impossibility. Your car, for example, cannot burn more gasoline than you put into it. Our recent reports on electromagnetic harvesters have led to the question: are they stealing electricity?

Apparently this is the case. A farmer in Idaho had a barn located near high power lines and noticed that baling wire he kept in his barn was conducting small amounts of electricity. After some investigation he built induction coils and began to run his house off of it. Power company equipment detected the drain of energy and went to investigate. The farmer was arrested for using electricity from the power company without a meter.

In another case, an engineer living at a military base in England lived in a house near a radar installation. He installed induction coils in his attic that generated electricity from the radar beam. Controllers in the radar facility noticed a strange shadow on their screens and he was caught.

The theory is that electromagnetic fields around power lines create current that flows in the induction coil or a dipole. By making a small coil, about the size of a human hand, wrapped around a ferrous iron core and placing it on top of a power pole transformer, or on a typical home or farm transformer, a flow of electricity can be generated. Vertical copper wires inside the coil running perpendicular to the power lines connected to a bridge rectifier, a load resistor and a ground wire, capacitors or voltage regulators can generate significant current. Since radiated energy drops off at the square of the distance the coil has to be very close to the power wires.

Power companies have sophisticated measuring equipment to detect losses of energy along their power lines. For example, a marijuana growing operation in California built a house around a cavern entrance and grew plants in the cavern using high-tech lights tapping electricity illegally from nearby power lines; this shows that any significant tapping of power lines will be detected.

While electromagnetic harvesters are interesting and may yet have commercial application siphoning energy from the electric grid would certainly meet with legal challenges as has already occurred.
http://www.industrytap.com/electromagnetic-harvesters-free-lunch-or-theft/1805


View: https://www.youtube.com/watch?v=pyGZTiSeKjY

 

[classic33]

[QUOTE 4873859, member: 9609"]well found - I'm sure it was the farmer in Idaho, however I think in the original story he wasn't found out until he showed off about his clever plan on the internet.. I would be surprised if a power company could detect a small amount of leccy being lost form high voltage pylon grid stuff (@swansonj ) if memory serves me right I'm sure it was less than a kw he was pilfering.[/QUOTE]
If someone told you that story would you believe them?

A Practical Guide to Free-Energy Devices if you feel like having a go at it yourself!
Or if instructions are required to build one.

 

[KnackeredBike]

I'm not sure I believe the stories for HV lines, surely even a decent amount abstracted would be negligible compared to the amounts lost through the transmission network normally. I would imagine most people are caught because they find it difficult to keep their mouth shut about their own ingenuity, and it is of course in the electric company's interest to imply they were caught due some amazingly complex monitoring system.

 

[swansonj]

"Unlawful abstraction of electricity" is a specific offence defined under the Theft Act. The story I was told as to why a specific offence is needed is that the definition of "theft" involves the intention to permanently deprive someone of something, and it is quite difficult to pin down in legal terms what it is that you are "permanently depriving" someone of when you steal electricity (it's not the electrons, obviously).

The vast majority of electricity stolen is at low voltages, by fiddling with meters or tapping into street lights etc. I don't think my employer would be too happy if I posted on a public forum too much detail of the methods people use or of the methods we use to detect it . But may I just say that the idea that you can slow down a rotating disk meter significantly by bringing a bar magnet up close to it is false. I tried it. In the interests of research of course.

 

[Drago]

Electricity has no physical form, so can not be regarded as property. Hence abstraction of electeicity instead.

When the sun shines my electricity meter runs backwards due to my solar. I'm not sure it should be that way, but the solar people reckon its fine and it is nice to watch the numbers go backwards.

 

[swansonj]

Electricity has no physical form, so can not be regarded as property. Hence abstraction of electeicity instead.

When the sun shines my electricity meter runs backwards due to my solar. I'm not sure it should be that way, but the solar people reckon its fine and it is nice to watch the numbers go backwards.

A bloke once suffered a power cut when the overhead lines blew down, and he thought the electricity company were taking too long to repair it. So he got a portable generator and connected it to the ends of the blown-down wires to supply his home. Not realising that all the electricity he generated (at his own fuel cost) was passing through his meter, and therefore the electricity company would still be charging him for it...

 

[Bollo]

When the sun shines my electricity meter runs backwards due to my solar. I'm not sure it should be that way, but the solar people reckon its fine and it is nice to watch the numbers go backwards.

Because I do physics and stuff I can tell you for fact that you're making time itself run backwards. Stand too close to the meter and you may return to childhood, although I sometimes doubt you ever left it.

 

[Bollo]

Whimsy aside, I've had a nasty crack of static after I've been on the rollers for a while and then grabbed a nearby metal shelf when I'm getting off. On more than one occasion it's nearly caused a youtubetastic roller fail.

 

[swansonj]

[QUOTE 4874065, member: 9609"]they can make a lorry go faster though - so I'm told[/QUOTE]
The usual claim is improved fuel efficiency rather than speed. It's of the same ilk as using magnets to soften hard water or to speed up bone repair following fractures. All are controversial, and I mean that literally rather than as a euphemism for wrong. Undoubtedly many of the claims made are invented and specious, and if there was something in it you'd expect it to be more widely taken up, but there are a few scientific reports that make it hard to dismiss entirely. There is possibly more of an underlying physics basis for softening water (to do with changing the surface characteristics of nucleation sites) than for fuel efficiency. Bone repair may just be that being plugged in to one of those machines forces you to stay immobile for long periods of time.

 

[subaqua]

I am Glad @swansonj has done the answering .

Loving the bit about putting the Gen set on the lines.

 

[swansonj]

[QUOTE 4874120, member: 9609"]this was a practise that was well and truly stamped out many years ago, huge fines then redesign means it no longer happens. basically strategically placed magnets disrupted the speed sensors which would stop the limiter cutting in. try putting a magnet next to the sensor on you bike wheel and it won't work[/QUOTE]
Ah - sorry - I misunderstood- I hadn't heard of disrupting the speed sensors, but I had heard of people clipping magnets to fuel lines to improve the fuel efficiency.

 

[mgarl10024]

Great anecdotes and answers on here. What a wonderful thread.

Incidentally, I can confirm that since deliberately resting fingers on the metal brake levers, no shocks have been felt.