I've heard of "dirty electricity" causing monumental health problems, and that it is not a good thing to have in your house.
They also say that energy efficient devices cause this "dirty electricity".
Are they to be trusted?

Links:
http://greenwavefilters.com/
http://www.dirtyelectricity.org/index.shtml

I do know about power factor.

These are essentially just a big capacitor in a box, and can make the problem worse. Lots of companies (Like the 2 that you posted) Make a living scamming people.
These companies are not to be trusted, the same can be said about people selling "Power Savers" that plug in, they don't do anything except make the bill higher!
Don't waste your time with them a little research would have helped you.
See Here

I kind of already knew that it was nonsense, but I was wondering if there was any hint of truth to it.
How many people have actually gotten these "filters" and installed them in their house?
I've seen videos of those "energy savers" that really just correct power factor.

There was never any truth in it at all. To filter surges, get a surge protector. That's all that really needs to be said about this one

But then why don't people take action against them?

But then why don't people take action against them?

Because nobody cares enough to take action, and a petition won't help, they've been going for years.
Too many details to explain why.

It's yet another scam. But next we have the overly health-conscious people who are afraid of fluorescent lighting because "fluorescent lights are unhealthy."

It's yet another scam. But next we have the overly health-conscious people who are afraid of fluorescent lighting because "fluorescent lights are unhealthy."

Didn't I already say it was a scam?

i found one of these devices in a box of junk.it is the "greenplug"
supposed to throttle your refrigerator and save money.my test showed it to increase monthly usage as measured by my kill a watt.
most energy/fuel saving devices are scams.

Didn't I already say it was a scam?

You did, but I'm summing it up.

Does your refrigerator plug through this device ? If no, it cant affect the refrigerator at all. And if it is a separate device (that nothing plugs into), then if it affected your usage noticably it must have dissipated real power, so got quite hot....

I doubt there is really anything more than an indicator LED with resistor inside, maybe a capacitor of random value at most



There really is such thing as Power Quality issues, which the average user calls "dirty electricity". But there is nothing in common between the actual problem/its real solutions and any of those "magic Green devices"

But the only place where the power factor correction devices would work is in industrial places, where you might get billed for bad power factor.

But the only place where the power factor correction devices would work is in industrial places, where you might get billed for bad power factor.

But there you are billed when the power factor is bad in both directions. So the compensation has to really respond to the actual condition. So these dumb capacitors are making the thing only worse (with light load they overcompensate, so cause bad power factor as well).
And this metering system applies only for power levels order of magnitude larger than typical for homes (delivery capacity in MVA and above), so these things would be way too small to really work anyway...

If we go back to health effects and try to make sense of what is being talked about, the underlying assumption of all this "dirty electricity" talk is, that for the same radiated power, EMF at >> 50/60Hz is more harmfull than EMF at 50/60 Hz. So, if your wiring is radiating some EMF out, then when the EMF contains HF noise in it, its more harmfull..

It definitely is more harmfull to the reception of various other electronic devices. Can hear it well on AM radio when somebody around uses a PC with cheap power supply that puts HF noise into the power line

I dont know whether it is or isnt more harmfull (than 50/60 Hz) to health of us or other Pokemons



So if we take it, that the problem is HF noise induced into the power line by some switching power supply (ballast, PC power supply, pretty much anything else)

First, what deivce is makign the noise and why ? Devices must be designed to not make a mess on the power line. The ones that do, are usually the cheap Chinese stuff that should not be used anyway for being generally of substandard quality / unsafe / fake power rating and such, and not for the EMI issues specifically

is the HF noise between Phase / Neutral ? Or is it between Phase+Neutral / PE ?

 = If the noise is between Phase / Neutral, it won't usually radiate all that much from the electrical wiring anyway. The reason is, that Phase and Neutral conductors go the same path in the wall, so their fields pretty much cancel out. This does not apply if some bright spark who wired the house pulled Phase and Neutral to something from different places (this situation is always result of a hack job, there are no legit electrical installations where this happens)

 - If the noise is between Phase+Neutral / PE, it may get interesting if there is more than one way of PE coming from the device. For example : Computer with shielded data cable connecting it to somewhere else (where there is its own PE), electronically ballasted luminaire installed on metal grids of suspended ceiling (that connects somewhere to other structural metal or intentionally wired to electrical PE with its own jumper cable), and so on. The HF current then might take the route of Phase+Neutral on one side and the "other" PE on the other side. Nothing posible to filter in this case by any remote filter, except filtering and preventing the creation of the EMI inside the device itself

Most of the "Green Magic" devices that have SOMETHING inside (and not just the LED + resistor) are a cpacitor between Phase / Neutral. So they would pass any HF component there, but why would it matter ? For all we know, if the computer OR the "Green Magic" device are plugged into a circuit where Phase and Neutral take different routes, it might actually encourage the HF component to go around the formed loop, and increase the EMF.. Otherwise it would do nothing at all



Power factor correction for linear loads (what is done by connecting a capacitor in parallel with the line) is only shifting the phase between voltage and current. As the phase DEFINITELY have no effect on health whatsoever, so there is no relation between PF correction and health

And in an industrial area, you can't just use cheap little plug in power factor "correction" devices.