Harry Veeder wrote: I don't agree with their concluding paragraph or that the demand for > lighting > will necessarily rise, but I think from a macroeconomic standpoint the > total > demand for energy will at least remain unchanged because the money saved on > lighting will be invested in other forms of energy consuming production. >
That might happen to some extent, with some people, in some countries. But it is not happening here. Per capita energy consumption in the first world has fallen since the 1970s, even in the U.S. First world people already consume as much energy as they can -- and as much as they find convenient. It would be an imposition to consume more.Take automobiles. They are the least energy efficient machine in common use. The popularity of SUVs made them even more inefficient and dangerous, but I doubt there will anything like that in the next 50 years. I predict that any change is bound to be an improvement, and they will soon get over 100 mpg. Now, here's the thing: traffic is so bad that most people in the first world would not drive more even if they could. Even with a cold fusion car with a fuel cost of zero, most people would not increase their driving. And there is no place to build new roads in most urban areas. So, consumption of automobile mileage -- which is the biggest and most wasteful category of energy consumption -- is maxed out. This goes back to the point made by Steven Johnson: Who would want to live in a house with lights as bright as the sun in every room?!? There is an upper limit to how much a normal, sane person want to consume. There are pathological spendthrifts such as Michael Jackson, but they are rare. Efficiency in space heating, transportation and industry has much farther go before we begin to reach the thermodynamical limits. That's assuming you use the same technology indefinitely into the future. That is not a given. When you substitute video-presence for travel or daily commuting, suddenly you reduce energy consumption by a factor of 100,000 to accomplish the same purpose more conveniently and effectively. When you substitute an indoor farm in an urban center for a conventional outdoor farm, you decrease energy use for farming and eliminate transportation costs. The Sci. Am. years ago gave some other good examples, such as machine tools that form parts by pressing metal powder together under pressure and heat. This consumes less energy than cutting the same parts out from a block of metal, or casting and then filing it. In grocery stores, better inventory control software and just-in-time resupply has greatly reducing spoilage and losses from unsold food. That's getting something for nothing: a computer program gives you thousands of heads of lettuce and packages of frozen pizza that would have been thrown away in the past. (This is causing problems for food banks.) These are far larger gains than you get from merely optimizing equipment to accomplish the same tasks by the same old methods. Vaccinating chickens and enforcing standards to keep salmonella out of food not only saves people's lives and prevents misery, it also saves a terrific amount of material and food that has to be thrown away -- such as 500 million eggs. Improvements that reduce material waste usually save energy. You don't think of a chicken vaccine as a way to save energy, but it amounts to that. In the third world and China, energy consumption per capita is low, but efficiency is even lower. It is unbelievable bad! Lighting, for example, is typically from kerosene. As I recall that is about 3 orders of magnitude less cost efficient per lumen, not to mention dangerous. Third world people who earn a few dollars a day *pay more* for lighting than we do. I mean the absolute dollar amount they pay per year is more, and of course they can only afford 20 minutes of inadequate lighting per day. If we could give every single third-world family LEDs driven by solar batteries, worldwide consumption of energy and oil in particular would fall quite substantially. To take another example, third-world use of automobiles in many countries is a nightmare of grotesque inefficiency. Washington DC and Atlanta have the worst traffic in the U.S. but compared to Mexico City, Beijing or San Palo they have no problem at all. - Jed
