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Pros and Cons


1. AC requires more push to get through the lines, thus wastes precious power

I assume that the word "push" equates to "voltage". If one assumes that the comparison of AC to DC is assuming the same line material (copper), line diameter, and line length, then this statement simply isn't correct. Both AC (at low frequencies like we use at home) and DC abide by the same laws of physics. This is commonly referred to as Ohm's Law, which is I=E/R; that is, current (I, amount of electricity) is equal to voltage (E or "push") divided by resistance (R or "the ability to impede" the flow of current). Thus, if E and R are the same in our comparison of AC and DC then "I" (amount of electricity) will also be the same.

2. AC devices assume the voltage from the grid

I am assuming that by "grid" we are talking about the set of electric "lines or wires" that distribute the electricity from it's source to the various places where it will be used.

If my assumption is correct, then the statement is incorrect. The AC that we use in our homes leaves the source - generation plant - with a voltage of many thousands of volts. It is then distributed to a series of substations which, using transformers, ultimately reduce the voltage running along the power lines along the street to several hundreds of volts. Finally, atop every few "power poles" you will find still another transformer which finally reduces that "several hundreds of volts" to your normal 115-120 volts AC that comes to your individual house (of course, the exact numbers are different in different parts of the world).

Were DC used at the generation plant for distribution such a long distance, hugh diameter power lines would be required to minimize the R value, and transformers could not be used as they only work with AC. Therefore you would have very much higher voltages coming into your home.

3. DC devices such as made for camping require less push

Correct because the DC source ...battery... is only a few feet away. The largest RV's I've seen are 5th wheel campers no longer than around 45 feet.

4. DC conserve energy, especially when the production and use are same locale

The key word is "same locale". To go any distance you need very large wire or AC and transformers. Transformers do "waste" a fraction of the energy. It is a "trade off".

5. DC camping lamps and heaters and whatever use 12V

True except for heaters; at least my RV didn't use 12V for the heater except for the fan. Also, when I put my "made for RV" refrigerator (which generates heat to make cold!) on 12V mode, even while on the road and the battery was charging from the truck generator, the RV's deep cycle 12V battery bank was still depleted.

6. AC and high voltage are dangerous for family group to try to produce (read electrocution)

No need for AC and high voltage if the source is close to where it will be used. Otherwise I would suggest that one read a little history on the subject of DC vs. AC for distribution. Whether AC or DC, for practical wire size High Voltage is required. Edison first lit parts of New York City with his new electric lights using DC. Death rates were enormous because of very high voltages hanging over the streets and sometimes falling and going into homes where accidents happen. If one does accidentally get hold of a high voltage DC line, one can't let go; where with AC the opposite is true. Westinghouse developed AC and went into competition with the Edison Electric Company and in short order DC was relegated to low voltage battery applications.

Offered by Ron.

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