I never (as in seldom) build power plants on my home island. I never gave this any thought until I captured some city on another Island with a power source (don't remember what it was) and thought why don't I build one to increase production in one of my cities. BUT, The choice of a power plant (Hydro, Nuclear, or conventional Power Plant ) did not appear in any of my home island cities "what shall we build" list, although I had the prerequisite advances. It seems that after you build the Hoover Dam wonder that no other power source can be build on that Island.
The manual states:
Power Plant Clarifications: All three types of power plant increase the base resource production of a city by 50%, before the effects of a Factory or Manufacturing Plant are
considered.
This does not seem to be true. - But it is, in the example below the city with a production of 6 shields, gets 9 with a factory and only 3 more with a power plant (50% of 6 is 3) so total production = base production + (50% X base for factory) + (50% X base for power plant)
I also noticed:
When you get the advance of Electronics, the Hydro Plant city improvement appears in the "what shall we build" list of a qualifying city (one on a river or next to a mountain).
When you get the advance of Nuclear Power,the Nuclear Plant city improvement appears in the "what shall we build" list of any city you control.
With the advance of Refining the Power Plant city improvement does NOT appear in the build list. The Power Plant city improvement only appears after you build a factory.
Example city produces 6 shields
with factory: 9
with Factory & Power Plant:12
Example city produces 10 shields
With Nuclear Plant (no factory) it is 10 no change, but the Hydro Plant choice is NOT displayed in the "what shall we build" list.
With Hydro Plant (no factory) it is 10 no change, but the Nuclear Plant choice is NOT displayed in the "what shall we build" list.
When you build the Hoover Dam wonder - The Hydro Plant , the Nuclear Plant, and the Power Plant city improvement don't appear in the "what shall we build" list.
So what does all of the mean? That you can only have one power source?
From my observation it looks like there is no increase in production for any power source until you build a Factoryor Manufacturing Plant.
Hoover Dam:...all cities on the same continent ...increasing the resources generated by the city by 50%. In addition, the Dam reduces the probability of pollution from these cities.
I guess it is implicit that the Hoover Dam 50% only applies to cities with a Factory. I always assumed that building the Hoover Dam increased production in each city on that island. I think I did it for the noticeable decrease of pollution in cities with a pollution source and didn't notice that nothing else happened.
Conclusion: What does all this rambling mean?
1) If you have Hoover Dam no other power source can be built on that island.
2) You can't build a Power Plant unless you have a Factory or Manufacturing Plant.
3) Construction of a Hydro Plant or Nuclear Plant has no effect* until you build a Factory or Manufacturing Plant.
* Not quite true see the following.
Pg80 Civ Manual - Hydro Plant reduces the probability of pollution.
A Nuclear Plant also reduces the day-to-day probability of
Pollution.
4)Once you have a Power Source (Hydro Plant, Nuclear Plant, Power Plant)
you can't upgrade unless you sell off the existing one.
5) I just never realized the intricate interaction of the different power sources.
6) I thought I had stumbled on to something strange but when I laid it all
out seems to make sense.
note: placing multi power sources in a city with a cheat does not multiply the power effect.
Edit: 27Jul2012 corrections in blue
The manual states:
Power Plant Clarifications: All three types of power plant increase the base resource production of a city by 50%, before the effects of a Factory or Manufacturing Plant are
considered.
This does not seem to be true. - But it is, in the example below the city with a production of 6 shields, gets 9 with a factory and only 3 more with a power plant (50% of 6 is 3) so total production = base production + (50% X base for factory) + (50% X base for power plant)
I also noticed:
When you get the advance of Electronics, the Hydro Plant city improvement appears in the "what shall we build" list of a qualifying city (one on a river or next to a mountain).
When you get the advance of Nuclear Power,the Nuclear Plant city improvement appears in the "what shall we build" list of any city you control.
With the advance of Refining the Power Plant city improvement does NOT appear in the build list. The Power Plant city improvement only appears after you build a factory.
Example city produces 6 shields
with factory: 9
with Factory & Power Plant:12
Example city produces 10 shields
With Nuclear Plant (no factory) it is 10 no change, but the Hydro Plant choice is NOT displayed in the "what shall we build" list.
With Hydro Plant (no factory) it is 10 no change, but the Nuclear Plant choice is NOT displayed in the "what shall we build" list.
When you build the Hoover Dam wonder - The Hydro Plant , the Nuclear Plant, and the Power Plant city improvement don't appear in the "what shall we build" list.
So what does all of the mean? That you can only have one power source?
From my observation it looks like there is no increase in production for any power source until you build a Factory
Hoover Dam:...all cities on the same continent ...increasing the resources generated by the city by 50%. In addition, the Dam reduces the probability of pollution from these cities.
I guess it is implicit that the Hoover Dam 50% only applies to cities with a Factory. I always assumed that building the Hoover Dam increased production in each city on that island. I think I did it for the noticeable decrease of pollution in cities with a pollution source and didn't notice that nothing else happened.
Conclusion: What does all this rambling mean?
1) If you have Hoover Dam no other power source can be built on that island.
2) You can't build a Power Plant unless you have a Factory or Manufacturing Plant.
3) Construction of a Hydro Plant or Nuclear Plant has no effect* until you build a Factory or Manufacturing Plant.
* Not quite true see the following.
Pg80 Civ Manual - Hydro Plant reduces the probability of pollution.
A Nuclear Plant also reduces the day-to-day probability of
Pollution.
4)Once you have a Power Source (Hydro Plant, Nuclear Plant, Power Plant)
you can't upgrade unless you sell off the existing one.
5) I just never realized the intricate interaction of the different power sources.
6) I thought I had stumbled on to something strange but when I laid it all
out seems to make sense.
note: placing multi power sources in a city with a cheat does not multiply the power effect.
Edit: 27Jul2012 corrections in blue
.