Slashdot Mirror

Electric utility rates have several components
Some are related to the energy used
Some are related on the cost of having the infrastructure to deliver energy to your location
And then there are the hookup fees related to running wires from the nearest location where the utility has available capacity.

The problems feeding bitcoin miners power are similar to the ones electric cars create with their battery chargers.

The POCO sizes the delivery system for the expected demand, If the customer is doing something unusual (Grow House, Electric Car Charging, or other concentrated demand) the average load can be much higher than delivery capability. Load Diversity

Who says the storage center is implemented well?

Angela Merkel

Who is chancellor of Germany. Yeah like she was briefed on this: http://www.mikeholt.com/img/mojonews/whatisarcflash.jpg

http://www.mikeholt.com/technical.php?id=grounding/unformatted/Groundrodfault&type=u&title=Ground%20Rod%20Does%20Not%20Assist%20in%20Clearing%20a%20Fault%20(01-25-2K) http://forums.mikeholt.com/showthread.php?t=107483&page=2 and http://forums.mikeholt.com/showthread.php?t=139984&page=6

explain why a ground rod does not assist in clearing a fault. The problem is not the copper ground rod but the earth itself. A proper grounding conductor is the bare copper wire that's part of the branch circuit wire that eventually goes back to the equipment grounding bar in a sub- or service (main) panel.

http://www.mikeholt.com/technical.php?id=grounding/unformatted/Groundrodfault&type=u&title=Ground%20Rod%20Does%20Not%20Assist%20in%20Clearing%20a%20Fault%20(01-25-2K) http://forums.mikeholt.com/showthread.php?t=107483&page=2 and http://forums.mikeholt.com/showthread.php?t=139984&page=6

explain why a ground rod does not assist in clearing a fault. The problem is not the copper ground rod but the earth itself. A proper grounding conductor is the bare copper wire that's part of the branch circuit wire that eventually goes back to the equipment grounding bar in a sub- or service (main) panel.

http://www.mikeholt.com/technical.php?id=grounding/unformatted/Groundrodfault&type=u&title=Ground%20Rod%20Does%20Not%20Assist%20in%20Clearing%20a%20Fault%20(01-25-2K) http://forums.mikeholt.com/showthread.php?t=107483&page=2 and http://forums.mikeholt.com/showthread.php?t=139984&page=6

explain why a ground rod does not assist in clearing a fault. The problem is not the copper ground rod but the earth itself. A proper grounding conductor is the bare copper wire that's part of the branch circuit wire that eventually goes back to the equipment grounding bar in a sub- or service (main) panel.

Mike Holt has a whole sub forum dedicated to power quality and surge protection (Power quality + Surge forum)

Mike has also written the books on grounding and bonding - Grounding vs Bonding text book

Mike Holt has a whole sub forum dedicated to power quality and surge protection (Power quality + Surge forum)

Mike has also written the books on grounding and bonding - Grounding vs Bonding text book

http://www.mikeholt.com/mojonewsarchive/LSP-HTML/HTML/TVSS-Protection-Questions-and-Answers~20040708.php

Those guys know their electricals.

Damage from a close lightning strike will probably not be mitigated by whole house surge suppressors. But I would still install one. The important point to look for is UL 1449-listed devices. Then at specific locations, install a good surge suppressor. Kinda like computer defense-in-depth. Something from ZeroSurge will help if your home is old and doesn't have ground; otherwise, a normal MOV surge suppressor requires good ground. This would be equipment ground and is not the same as your grounding rods/water pipe ground. The latter are really for lightning strikes. ZeroSurge doesn't use MOVs and don't rely on equipment ground. You may also want to consider getting a line conditioner but I haven't done any research on their viability.

I'm looking at the Leviton 51120. Depending if your house is single or three phase, you'll need to get the right model for the type of service you're receiving. The Leviton is nice because it comes with its own J-box for extra protection. Eaton (Cutler-Hammer) has one but it's normally attached on the bottom of the buss bars while a lot of other companies recommend their TVSSes be installed on a breaker that is the closest to the service conductors. I prefer the standalone devices like the Leviton because they could be installed on any panel instead of a specific brand. The Leviton can also pigtail into an existing breaker. If you have Eaton/Square D QO breakers, you could attach up to 2 hots per breaker.

If you do decide to get one installed, make sure you or the electrician make the conductors as short as possible and don't create too sharp a turn in them.

I should not have used "real power" earlier for VA, I did screw that up. Watts is real power, VA is apparent power.

Quoting the wiki article:
"For example, to get 1 kW of real power, if the power factor is unity, 1 kVA of apparent power needs to be transferred (1 kW ÷ 1 = 1 kVA). At low values of power factor, more apparent power needs to be transferred to get the same real power. To get 1 kW of real power at 0.2 power factor, 5 kVA of apparent power needs to be transferred (1 kW ÷ 0.2 = 5 kVA). This apparent power must be produced and transmitted to the load in the conventional fashion, and is subject to the usual distributed losses in the production and transmission processes."

A straight reading of that would seem to say that the generator is doing 5 times the work to deliver the same real power. Is this an incorrect interpretation?

From further down in the same article:
"The significance of power factor lies in the fact that utility companies supply customers with volt-amperes, but bill them for watts. Power factors below 1.0 require a utility to generate more than the minimum volt-amperes necessary to supply the real power (watts). This increases generation and transmission costs. For example, if the load power factor were as low as 0.7, the apparent power would be 1.4 times the real power used by the load. Line current in the circuit would also be 1.4 times the current required at 1.0 power factor, so the losses in the circuit would be doubled (since they are proportional to the square of the current). Alternatively all components of the system such as generators, conductors, transformers, and switchgear would be increased in size (and cost) to carry the extra current."

My experience with electrical systems is in terms of building design, transformers, and standby generator sizing, which is all about designing around the largest load.

While doing additional searches, I came across this post which does a nice job of explaining it as a beer metaphor.

Incidentally, after reading the entire corpus of ordinances pertaining to parking, I discovered that I was in the right after all, and photocopied the sections of the book for the occasion of receiving a ticket. Oops. Guess I broke some copyright laws there.

Actually, you didn't.

Laws are automatically "public domain" as are gov't-produced documents. Low-budget film compaines routinely take advantage of this to get cheap footage.

Although the gov't charges $800 per copy, it should be legal for you to just photocopy the entire book and start selling copies for as much (or as little) as you want.

Here is an example court judgement which backs up my opinion.
In this case the judges decided that even if some body of text was already copyrighted, by becoming a law it automatically enters the public domain.