The discovery of Environmental Economics in my games of Alpha Centauri was always a turning point, as at that point (unless I was playing with the occasional faction, or in the occasional world, that made the following approach inefficient), I began moving, or preparing to move, from leading my people "dictator style" (martial-law units,
bread and circuses like
recreation commons and the automatic drone control effect of
hologram theatres) to "democrat style" (or... erp... perhaps "socialist style"):
recycling "money" (energy) from the people back to the people in the form of luxuries (to use the
Civ II term).
This was also the point at which I started moving from an heavy-industry-based, local economy towards an energy-based nationwide economy.
(Game-mechanics explanation:
Tree Farms (/me coughs, gags at name) are superb-though-expensive facilities for converting energy collected at their host bases into "money" and into "luxuries," making it
safe for their host cities to grow. Meanwhile, they vastly increase the food production for their host cities if these were developed by a wise and patient
Johnny Appleseed, making it
possible for the cities to grow. Their more expensive twins, one advance up the same branch,
Hybrid Forests, do the same, but more of it.
Also note that the most cost-efficient purchases using "money" energy are completions of
facilities... like more Tree Farms.)
Thus Environmental Economics is the
start of a beautiful "energy ecology":
Forests (terrain improvement) --> sustainable, prob. biomass-based (perhaps
hemp? :0) forestry in the form of "Tree Farm" facilities --> food for local growth, luxuries for preventing local
civil unrest, immediate "money" energy boost, medium- and long-term boost in local energy production (and industrial production) from mentioned growth --> ability to purchase more Tree Farms (and later Hybrid Forests)...
You get the picture. This is perhaps the closest thing
SMAC has to the
President's Day Sale in
Civilization II, but unlike the PDS, which is a
game-mechanics parable on the power of
social-contract governments alone, the... um... Arbor Day Sale speaks of that AND subversively plugs
sustainable energy and
sustainable economics.
Things like this -- the points where
Sid Meier 4x games reward you for doing things that
get you thinking in a wider scope -- are what make their addictiveness almost excusable.
They sit together
The forests, mines, and farms
Until only the forests remain