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To: Drammach
The simple step of removing electrical power losses due to transformers could result in 5% or 10% reduction in community energy consumption in this country.

Transformers are not wonderfully efficient, but ohmic losses at low voltage can be devastating. If a device only requires a quarter watt, ohmic losses at 12 volts wouldn't be much of a problem, but even a 50% efficient transformer wouldn't waste much energy. Products that require real power, however, are another story.

Consider a product which requires 112 watts, is located 100 feet from the power supply, and is connected to a 12-volt supply with #6AWG cable (that's like booster-cable wire!). Such cable has a resistance of about 0.0004 ohms/foot, so the total resistance would be 0.08 ohms. With 10 amps flowing through it (as would be the case with a 112-watt load) the wire drops 0.8 volts. Despite the large cable, over 8 watts gets wasted in the wire!

Now consider a 119.75-watt device powered 100 feet away from a 120-volt source. Such a device may be powered with over 98% efficiency using 18-gauge wire (0.0063 ohms/foot, or 1.25 ohms total). The wire would drop 1.25 volts, wasting only 1.25 watts.

As a couple of additional points of comparision, using #6 cable would result in less than 100mW of loss; if 5% loss were acceptable, 24-gauge wire would suffice.

48 posted on 05/05/2002 11:52:41 PM PDT by supercat
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To: supercat
Your points concerning high wattage appliances are well taken.
That is why I made the point of commenting on them as a separate concern.
I of course, realize that things like Air Conditioners, Electric Heaters, Stoves, Furnaces, all utilize high amounts of energy, and in such instances, must be handled differently.

Try this alternative.
Don't use electricity for these devices, use Natural gas.
High efficiency Gas Furnaces are rated in the 90% to 98% efficiency rating nowadays.
Much more efficient than any electric furnace.

62 posted on 05/06/2002 8:34:51 PM PDT by Drammach
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