I didn't realize you were the same person. Sorry about that.
There are two points here I think you need to examine more closely.
First is that there needs to be some "silver bullet" solution. I don't think there is, and I suspect that Gav would agree. He reports on multiple approaches to our energy problems, as do the people at
WorldChanging and elsewhere, and I think that's how we are already starting to deal with the situation. Wind here, solar thermal there, solar photovoltaic over there, geothermal in Iceland and East Africa, tidal in a few places, etcetera -- whatever makes sense for that area, combined with a distribution system to take any extra generation to places that need it can keep the juice flowing as the fossil fuel prices become
comparatively more expensive.
The second thing I think you should consider is "business as usual". Business as usual for one time period lives only a short time as costs and circumstances change. Don't think that energy-generation and manufacturing today operate like they did in the "classic" smokestack industry days of the early 20th century. These sectors will be even less like that fifty years from now.
But if you use the term "business as usual" to refer to profligate habits of consumers and households, that can change too. Something like that has already
happened in California. Higher prices have curbed demand, more-efficient devices have allowed people to do the same things with less energy, and (despite all its other problems) California is still going.
If we have to go through a period of energy scarcity (and thus high prices) before the better tools (which cost
comparatively less to operate) are well-distributed, that doesn't spell the end. If we all had to go back to a level of electric consumption from, say, 1980, you have to remember that that time still had an industrial society.
I'm curious about how old you are. Do you have a sense of how much life is different now than it was thirty years ago? The slow unrolling of the microcomputer revolution has changed life for millions, but in steps over time. The same can be said for electronic telecommunications networks over the same period. As others have pointed out, the internet and computers were here forty years ago. But only a few people had them. Only with time did "the future" get distributed. I think a comparable degree of change is already beginning in renewable energy production, prodded by the steady rise in fossil fuel prices and environmental consequences.
As for the end of industrial (or post-industrial) civilization, what is the sequence of events and the timeframe that you imagine? Your expectations might be more fast and hard and sudden than ours, and that's probably why a lot of us here think you are unduly pessimistic.