Combining ideas from the thread:
A pile of unique cards (at least 12), all of which are partially victory cards. Some are action/victory, some are treasure/victory, and some are pure victory. You pick 8 or 12 randomly, and the cards are stacked in a fixed order determined by a number written on the card. The top n cards are available to be bought or gained, where n is the number of players. As you go down the pile, the cards get more powerful, but more expensive.
All the action and treasure cards share the need to either discard, trash or play a card to get their effect, of which there'll be certain restrictions. This represents the different resources needed to power the plants in power grid.
To get the pile moving, maybe some of them could be strictly better than other cards (eg an "oasis" with 1VP for $3, a "stables" with 1VP for $5).
At least one card near the bottom of the pile will be a card that gives you VP based on how many of these you have, to represent the "power grid". I'd also envision one card simply being the most powerful card in dominion, like a straight 15VP for $14 - representing that fusion power station at the end of the pile in Power Grid.