TWO PUSHY MEXICANS

There remains a subtle technical point why a fluorescent light of the cheap type, with a choke for a ballast, will waste quite a bit of energy. To see why, consider first a mechanical analogy, two Mexicans pushing a rail car, as shown in the next column, one from behind, the other from the side.

Why Mexicans? Well, actually the nationality is quite irrelevant, but the top view is so much easier to draw for Mexicans with sombreros . . .

Anyway, mechanical work is defined as distance times force in the direction of the distance. When you lift 1 kg straight up by one meter, you have done work of 1 newton-meter (or 1 joule) against the force of gravity. If you lift it to the same height, not straight up, but by push-ing it up a ramp, it's still the same work, because only the vertical component of the force counts; the energy you spend in overcoming friction along the ramp is a loss contributing nothing to the work against gravity. Quite similarly, if Antonio (A) and Benito (B) push the car a certain distance applying the same force, Antonio does more work (against friction in displacing the car), because all of his force is in the direction of the distance; Benito's component of the same force F along the tracks is quite small, and he does very little useful work.

Now that does not mean they don't work equally hard in terms of sweat, heartbeat and fatigue; they may have the same losses of energy in the body, but Benito's losses accompany less useful work.

Something very similar happens when an alternating voltage pushes an alternating current through a conductor: the energy ex-pended (i.e., work done) equals voltage times current times dura-tion only if the first two are "in phase," performing their oscillations in harmony, both reversing directions at the same time. If they are not in phase, but one lags behind the other (as shown in the figure), then the energy consumed is less than the product of voltage and current, for much the same reason as the work done by Benito is less than that by Antonio. A simple choke ballast can shift the phase angle between voltage and current (analogous to the angle at which Benito pushes the car) almost to 90ø. (A full 90ø means Benito pushes like crazy and does no work at all.)

But your residential meter measures only the actual power con-sumed, voltage times current times a "power factor" which reduces this product to account for voltage and current not being in phase. So you pay only for that part of the current in phase with the voltage (analogous to that part of the force in the direction of the distance), i.e., only for the power actually consumed.

The remaining current, however, still flows and heats up the transmission line outside your home, and the utility pays for this loss: not out of the goodness of their hearts, but because the out-of-phase current drawn by residential equipment is so piddling that it is not worth the installation of special meters and the paper-work of billing.

Not so with industrial customers. They have all kinds of motors and other equipment that might shift the very large current out of phase with the voltage, and here the utility puts it in the wholesale contract, and monitors it very carefully, that the phase angle does not exceed a prescribed limit.

An incandescent light wastes more energy, but the useless heat is generated in your own home (voltage and current in phase), so you pay for it yourself. Fluorescent lights with "reactive" (out of phase) currents, on the other hand, cause losses paid by the utility.

Enter St. Amory the illustrious energy conserver: 17%, or whatever dubious percentage he has cracked up, of all electric energy goes for illumination, he thunders. If these stupid and un-patriotic consumers would only all switch to fluorescent lights, a majority of those diabolic nuclear plants could be shut down (de-electrification is the real objective of the campaign).

But if it were really 17%, then the total out-of-phase current would no longer be piddling, and residential customers would have to be treated like industrial ones.

No problem: Retrofit 92 million residential meters! Or bring on the Konservation Kommandos with secret random checks of the phase angle at your terminals! Pass legislation, edicts, prohibitions and decrees on how to manufacture ballasts! And send the bill to the rate payer.

Let me quote from a recent article ("How to improve energy efficiency," Iss. Sci. & Tech.) by Michael Shephard, director of the energy program at Rocky Mountain Institute, run by St. Amory, the illustrious energy-conserving free-marketeer:

"Gasoline taxes are not in themselves a strong enough induce-ment to markedly improve the efficiency of our vehicle fleet . . . Vehicle standards aren't the only laws that need strengthening . . . Congress should amend the National Appliance Energy Conser-vation Act . . . Some wasteful products have escaped regulation al-together . . . Motors aren't the only good candidates for new standards. DoE is currently exploring the impact of more com-prehensive standards for lighting systems, and several states, in-cluding New York and Mass., have already enacted them. (Fairly weak national standards already exist for the ballasts that power [?] fluorescent lights. Minimum standards have been proposed, but not enacted for windows, commercial refrigeration systems, buses, trucks, airplanes, office equipment, plumbing fixtures . . ."

[handcuffs, prison cells, meeting halls for mandatory collective in- doctrination, etc. Want a job paying in hard currency, comrades from Moscow's central planning offices?]