Given how incredibly wasteful our economy is regarding energy, I have a hard time believing that decreasing energy usage implies a contracting economy.  Eventually you would reach a point where this might happen, but there is so much fat in our economy that I cannot see this happening for a while.

There would be some economic pain for those whose role in the economy is to support the wasteful use of energy - those people would feel the pain right away.

Oh. Brilliant trick.

Just pronounce some segments of the economy "fat," then when they go, the economy is not really contracting.

The "fat" votes as well, we should remember.
I think there's a small cushion of "fat" that can be trimmed. If a consumer makes three trips in an SUV to run three errands, but can be persuaded by high gasoline prices to accept a little inconvenience and consolidate the three errands into one trip, less energy is used, but the errands still get made (i.e., the consumer-based economy continues to chug along).
Since the 70's our economy's supposed to have gotten pretty efficient with energy, relatively. This is not to say there are not more gains to be made (cutting that fat, I suppose), but we should be safer than the past.

Is the recent hikeup hitting energy intensive economies (China) hard? It would make sense.

Uhm. If we're already pretty efficient, doesn't that make us more vulnerable to the Extremely Clueless Physicist's scenario, not "safer"? Fat people should do better in famines, no?
We are amazingly wasteful regarding energy. In all aspects of our society, energy is so cheap, we don't even consider it - think of the open refrigerators and freezers in supermarkets. Energy efficiency is the cheapest 'source' of energy and can be as low as 3cents/kWhr. I think energy demand is viscous - elastic but slow. It takes time to adjust to a more energy efficient lifestyle. Awareness, new products, and energy effcient technologies have to be developed and deployed. For example, I'd like to buy a Prius, but my present car is 3 years old and fine. It doesn't make financial sense to trade. But my next car in three years will be a hybrid. When natural gas prices go up, watercooler talk will start to center on insulating hot water pipes, changing HVAC air filters, replacing windows with highly insulating windows, making sure the refrigerator coils are dust free.

Fast changes in energy price force consumers to eat the price before any adaptation, reducing other consumption, thus slowing the economy. The more slowly energy costs increase, the more likely we can adapt and still have a good economy.

Henry

Henry, if you're current car is three years old (we're in the same boat in a one car household with my wife's car being 3 years old), by the time you're ready to buy a new car, you just might be buying an all electric model instead of a gasoline hybrid. So look at the bright side, you might get to leap frog some technology.
Wholesale electricity from nuclear power plants in California is 2.8 cents a kW-hr.

Check the CPUC site.