# How can "...electrons flow in metals, but not in the ground..." explain grounding rods?

I really enjoyed Why is the charge naming convention wrong? But, in the comments at the very end, the statement that "...electrons flow in metals, but not in the ground..." left me uneasy.

I was taught that the physical process of "electron drift" was actually quite slow, and opposite in direction to "conventional current flow". So my question is, "Why do the utility companies, who use electrons as the carriers of electric current through solid metal power lines, make so many connections to metal rods driven into the ground? Don't electrons "actually" travel from one place to another? (i.e. up from out of the ground, through the grid, and back to the station?)

You are correct, electric current consists of electrons travelling from one place to another. Some materials conduct electricity better than others. Copper is one of the best and that's why our conductors are usually made of copper. Aluminium is also very good (so is silver) and high-voltage cables are usually made of aluminium.

However, everything conducts electricity to some extent. Even insulators do pass a tiny current - but they often conduct more across their (dirty) surface than through the interior. Soil and sand also conduct electricity, but their conductance is much lower than that of copper. To put it another way, they have higher resistance. If the soil is moist, the ions in the water will greatly increase the conductance.

Hence electrons will indeed flow from the copper rod into the ground.

The comment you saw is wrong. Yes, current can be carried by positive ions (like $H^+$, i.e. protons), but they only occur because a molecule (e.g. $H_{2}O$) has lost an electron. That electron is still moving and carrying current. The electrons from the rod will ionise some of the material in the soil, but it's still electrons that do the hard work.

• That does not answer this question. Feb 7 '16 at 10:19
• @hdhondt This comment is tardy, but I wasn't in a hurry to accept any answers. The above comment falsely claims you did "...not answer the question." Paragraph 3 does directly answer the question, but I think it is wrong. I asked if electrons come, "up from out of the ground, through the grid, and back to the station". Parts of your answer agree; paragraph 3 does not. Had you intended to state the opposite, it would support more of your answer. Also, my question was narrow on this one specific aspect: paragraphs 1&2 not needed. I will ACCEPT an edit that benefits your integrity and is fun 4 U
– user106404
Mar 26 '16 at 5:53
• Unfortunately, clouds can be positively or negatively charged. If the cloud is negative relative to the earth, the electrons will flow into the ground (electrons are negative). If the cloud is positive then electrons will flow from the ground to the cloud. Either way, the electron flow tries to balance the charge difference between cloud and ground. Mar 27 '16 at 9:52

Ground is at 0 potential,so,it accepts electron from negative terminal.

And at very far place any positively charged electrode accepts electron from ground and current flow.