Picture an apple tree – or pear, or whatever your fruit of choice may be. All the fruit is ripe, and it’s harvest time.
You start on the ground, plucking everything. And it’s easy. A couple of baskets are full in no time. But you’ve begun to need a bit more help. A ladder, and a bit of effort to work around branches. The baskets take longer to fill. And the further you go, as you try to get every last apple, the more difficult it becomes. Oh, you hit occasional branches that have clusters, but they’re matched by fairly bare areas where only one or two apples are in arm’s reach from the ladder.
Somewhere the apple picking got hard – you needed long ladders that were braced so you could reach the apples near the top, and that only for a few at a time. There are plenty of apples left. You can see them. And everyone can tell you that with more effort they can be reached. You know, though, that this effort will never make the apples fall into the basket as swiftly as those first ones – or even the ones you reached with a step stool.
Peak oil is nominally the point where half the apples – oil, sorry – has been drawn. We know it’s not going to come as easily, and what we do get will cost more effort. It’s not gone, it’s just… No more bushels of apples in a short time. It’s not running out. It’s just so much more time and effort (read dollars) for fewer than we got before that everything that assumes “easy oil” will be hit hard.