Power Plants: Everything You Wanted to Know But Were Afraid to Ask

[Catt]

Questions about power plants and how they work seem to come up pretty frequently, and I recently had a chat via PM regarding power plant questions -- I thought I'd post the same information shared in those chats. The following information is accurate as of Civ 3 PTW v1.21f (and to the best of my knowledge has been accurate for all prior version of PTW and Civ 3).

Everything You Wanted to Know about Power Plants

There are four different power plants available to the player: Coal Plant, Hydro Plant, Solar Plant, and Nuclear Plant. Power plants add a production bonus to the city in which they are built. To build a power plant, a city must first build a factory. All but the Nuclear Plant add a 50% production bonus to base shield output; the Nuclear Plant adds a 100% production bonus to base shields. The production bonus is calculated on “base shields available” which works as follows: (1) assume that a city’s laborers are working tiles and producing 38 shields, 6 of which are lost to waste, leaving 32 shields available; (2) the city’s factory adds 50% of 32, or 16 shields, meaning the city produces 48 shields; (3) adding any of the Coal Plant, Hydro Plant, or Solar Plant would generate an additional 16 shields (50% of the base of 32), increasing the city’s production to 64 shields; (4) adding a Nuclear Plant would instead add 32 additional shields (100% of base), bringing the city’s total to 80 shields (32 base, 16 factory, 32 Nuclear Plant).

Each of the available power plants become available at different points in the tech tree, and each comes with its own benefits and drawbacks.

Coal Plant. The Coal Plant becomes available at the same time as factories, with the tech Industrialization. In order to build a Coal Plant, a given city must have a factory and must have a supply of coal within its strategic resources box. A city with a Coal Plant continues to enjoy the production bonus of the plant even if the supply of coal originally needed to build the plant subsequently depletes, just as a city building a Coal Plant can complete the build even if the source of coal depletes prior to the plant’s completion. A Coal Plant generates pollution – 2 pollution icons. The Coal Plant costs 160 shields.

Hydro Plant. The Hydro Plant becomes available with the tech Electronics. In order to build a Hydro Plant a city must have a factory and a river must be present within the city’s 21-tile city radius. Note that the requirement is a river – a lake will not suffice. A city has a river “within” its radius if any tile within the radius enjoys the river commerce bonus. The Hydro Plant does not generate pollution. The Hydro Plant costs 240 shields.

Solar Plant. The Solar Plant becomes available with the tech Ecology. In order to build a Solar Plant, a city must have a factory. The Solar Plant produces no pollution. The Solar Plant costs 320 shields.

Nuclear Plant. The Nuclear Plant becomes available with the tech Nuclear Power. In order to build a Nuclear Plant, a city must have: (1) a factory; (2) a supply of uranium in its strategic resources box; and (3) a source of fresh water within its 21-tile city radius. Note that the requirement is fresh water – either a river or a lake will suffice. A city with a Nuclear Plant continues to enjoy the production bonus of the plant even if the supply of uranium originally needed to build the plant subsequently depletes. The Nuclear Plant does not generate pollution, but may meltdown (see below). The Nuclear Plant costs 240 shields.

One way to think about the various power plants involves imagining the chain of three conventional power plants as delivering increased benefits and reduced restrictions as you move up the tech tree. The first plant (Coal) requires a strategic resource (coal) and pollutes. The second plant (Hydro) doesn’t require resources, but does require specific terrain features (a river) and does not pollute. The third plant (Solar) requires neither a resource nor a terrain feature, and does not pollute. The final plant (Nuclear) offers a new production boost over the prior plants, but reverts to needing both a resource (uranium) and a terrain feature (fresh water); and while it doesn’t pollute, it can meltdown.

A city may have only one power plant. Any city that already has a power plant and then builds any additional power plant, will automatically sell the prior plant – the sale price in gold will be added to your treasury (and the recycled shields to your production box if you have discovered the tech Recycling). For example, if the player builds a Solar Plant in a city that already has a Coal Plant, the Coal Plant will be sold automatically and be replaced by the Solar Plant. Once replaced, an older power plant is gone for good – i.e., in the above example, if the newly built Solar Plant were sold or destroyed, the older Coal Plant would not reappear.

Meltdowns. According to the original Civ 3 manual, a nuclear plant has a 50% chance of melting down during any turn in which the host city experiences civil disorder. However, empirical testing indicates that the correct changes are about 10% - 15% (assuming the meltdown chances are a discrete variable, i.e., not influenced by unknown factors such as size of empire, number of city improvements, etc.). Furthermore, it seems as if the nuclear plant will never melt down on the turn that the host city enters into disorder – only if a city is allowed to continue through a full turn in a state of civil disorder is there a chance of meltdown. Anarchy - such as when you elect to change governments or are forced to do so by war weariness - is not a form of civil disorder and will not, in and of itself, cause a meltdown if your cities are not rioting. Although a meltdown graphically looks a lot like the effects of a nuclear blast, the actual effects are far less destructive. A city that experiences a meltdown will have its eight surrounding city tiles polluted and will have its population cut in half. However, neither units nor city improvements (not even the Nuclear Plant itself) will be damaged or destroyed. Furthermore, the pollution in the eight surrounding city tiles will not destroy the underlying terrain improvements such as railroad, roads, mines, etc., and will not cause the terrain itself to degrade (i.e., plains turning to desert). Once the pollution is cleaned up, the city will again grow and eventually return to the state it enjoyed before the meltdown.

Hoover Dam. The Hoover Dam great wonder provides the effects of a Hydro Plant to every city on the same continent. Even cities without a river in their 21-tile city radius or without a factory will have a Hydro Plant icon listed in their city improvements window. However, unless a city has a factory, the effects of the Hoover Dam will not operate on the city. For example, let’s assume that you have just completed the Hoover Dam great wonder. A nearby city that does not have a factory and that produces 30 shields will continue to produce 30 shields even though the Hydro Plant icon appears in the city improvements window. When that city subsequently builds a factory, the city’s production will jump to 60 shields – 15 shields from the new factory and 15 shields from the now-effective Hoover Dam effects. Additionally, cities that already have a different power plant (i.e., a Coal Plant) will also have a Hydro Plant icon in the city improvements window; however, each city enjoys the effects of only one power plant despite the appearance of two power plant icons in the city improvements window, i.e., the city will not enjoy both a 50% production bonus from its Coal Plant and an additional 50% production bonus from the effects of Hoover Dam. In cases where a city enjoys the effects of Hoover Dam but also has a Nuclear Plant, the city will enjoy the greater 100% production bonus of the Nuclear Plant. You should note that the city will continue to experience the burdens of any other power plants after the construction of Hoover Dam – a city with a Coal Plant on the same continent as the Hoover Dam great wonder will still incur the 3 gold upkeep cost of the Coal Plant and will still suffer the pollution generated by the Coal Plant, even though the sale of the Coal Plant would not change the productivity of the city since it would still enjoy the effects of Hoover Dam.

Manufacturing Plant. The Manufacturing Plant is not a power plant. Think of it as an improved factory. Like the factory, the Manufacturing Plant will add 50% to the production of a city. A city must have a factory to build a Manufacturing Plant, but may build a Manufacturing Plant despite the absence of a power plant. Again using our 32-shield city as an example: (1) such city would produce 48 shields with a factory; (2) such city would produce 64 shields with a factory and a Manufacturing Plant; (3) such city would produce 80 shields with a factory, a Manufacturing Plant, and any of the three “50% power plants” (Coal, Hydro, or Solar); and (4) such city would produce 96 shields with a factory, Manufacturing Plant, and a Nuclear Plant.

Catt

[Catt]

Thoughts on Power Plant Options and Tactics

I routinely build an available power plant in those cities that already contain a factory. If I have already made the determination that the boost to production afforded by a factory justifies the factory’s upkeep cost and pollution effects, it is likely to deserve an additional boost to productivity offered by a power plant. There are two broad exceptions to my general rule of thumb.

First, if I am reasonably certain that I will successfully build the Hoover Dam, I will likely not incur the extra production cost of building Coal Plants in those cities that will benefit from Hoover Dam. I may still build a Coal Plant in one or more cities to help their production solely for the purposes of completing the Hoover Dam, Theory of Evolution, or the Universal Suffrage great wonders, but upon the completion of the Hoover Dam, I will immediately sell such Coal Plants to eliminate the upkeep cost and pollution.

Second, in those instances in which either Hoover Dam is not built or in which I have productivity centers on a continent other than that which built Hoover Dam, I will first determine the effectiveness of manually building an available power plant. By and large, by the time power plants become available in the tech tree, most productive cities will already have a full complement of needed improvements – such cities’ likely building orders will be units: either infantry, artillery, tanks, or aircraft. If a city with a factory already produces 57 shields (after waste), meaning that its base production is 38 shields (with an additional 19 shields coming from the factory), adding a conventional power plant will bring production levels to 76 shields. For the purpose of building any of the Industrial Age units described above, production of either 57 shields or 76 shields makes no difference as all build projects will still require two full turns to complete. In such a case I am unlikely to add a power plant to the city. Of course (exceptions to the exception!), the raw boost in productivity would be attractive in completing more expensive build projects such as wonders or spaceship parts, and so even in the above hypothetical one or two cities may push forward and build an available plant. Some players also like to use older units to “short-rush” building projects (too much micromanagement for me). With a production of 76 (instead of 57) a player could disband an old pikeman, netting 7 shields (or rush build a worker and then change production to the desired unit) and then complete an artillery unit in one turn instead of two. Using such a play style would cause me to evaluate the benefits of a power plant differently.

In those games that remain competitive in the age of nuclear power a Nuclear Plant will often be more advantageous than ignoring the opportunity to build one because of the need to build multiple spaceship parts. The great drawbacks to Nuclear Plants are the upkeep cost and the potential for meltdown. But meltdowns are pretty rare and are not particularly painful. As explained above, a meltdown doesn’t damage units or improvements, and since the underlying terrain improvements like RR and mines/irrigation are left intact, available worker groups can usually clean up the polluted tiles fairly quickly. Where a Nuclear Plant would bump a city’s production over a “turns to build” hurdle, or would appreciably help in building spaceship components, I build the Nuclear Plant with little fear of a meltdown – employing the AI governor to manage citizen moods or otherwise carefully ensuring that no civil disorder descends on a city with a Nuclear Plant and is allowed to continue can effectively prevent any meltdowns. If a government switch is necessary in the age of nuclear plants, it pays to be careful about managing hapiness -- anarchy itself won't enable potential meltdowns, but since you lose any MP effects and all luxury spending during anarchy, cities that were content during a form of government can easily slip into disorder during the anarchy.

Catt

[Arrian]

[Panzer32]

Thanks!

I never knew nuclear plants were a bonus of 100%! Maybe I should play a game in the modern era so I can find out some of that stuff!!

[Chemical Ollie]

I only build coal plants in crucial cities that take part in wonder races. Then I sell them if I get Hoover.

[TheArsenal]

Valuable input, thanks. This, one of the several things I did not know, made it worth the entire read alone:

" ...– a city with a Coal Plant on the same continent as the Hoover Dam great wonder will still incur the 3 gold upkeep cost of the Coal Plant and will still suffer the pollution generated by the Coal Plant, even though the sale of the Coal Plant would not change the productivity of the city since it would still enjoy the effects of Hoover Dam..".

[vmxa1]

Originally posted by Panzer32
Thanks!

I never knew nuclear plants were a bonus of 100%! Maybe I should play a game in the modern era so I can find out some of that stuff!!

Just so you are aware that they can have a melt down.

[dexters]

Isn't Catt great ?

[vmxa1]

Originally posted by dexters
Isn't Catt great ?

I don't know about the great part, but I can say very much appreciated.

[Tattila the Hun]

What I Wanted To Know is why my moronic governor still wants to build cp's and sp's, even whe the whole continent has the effects of Hoover...

[Daz]

*smooches catt*

just for the record... I never build coal plants. I always go for Hoover. Hoover rocks!

[Chemical Ollie]

Originally posted by Tattila the Hun
What I Wanted To Know is why my moronic governor still wants to build cp's and sp's, even whe the whole continent has the effects of Hoover...

Artificial Intelligence is not.

[Cort Haus]

Originally posted by Daz
I never build coal plants. I always go for Hoover. Hoover rocks!

1. Hoov's been rockin' since Civ 1 and is still at it.

2. There's no harm in temporary coal plants to speed up the ToE and Hoov.

[Daz]

There's no harm in temporary coal plants to speed up the ToE and Hoov.

Agreed. But ONLY for that...

[Colonel Rhombus]

So, to clarify: A Nuclear Plant will never melt down so long as the city remains free of disorder?

[Arrian]

Hmm, isn't there a chance of it happening during Anarchy (even if the city isn't actually rioting?)?

Of course everybody goes for Hoover. Me, I usually try to set aside a great leader for it while building ToE

-Arrian

[Jawa Jocky]

Nobody ever thinks about the Migrating Fish when they through up Hydroplants. Hydroplants have several drawbacks....Oh yeah....there aren't any Salmon in Civ3.

Great Write-up. You forgot to give the Iron Works honorable mention.

[Arrian]

And they left out wind power, but whatcha gonna do, eh?

IW is a nice toy. Get a 40-base-shield city, throw in the IW, Factory, and Hoover, and you've got 120 shields/turn (aka 1-turn MA). I think.

-Arrian

[Yahweh Sabaoth]

A job well done, Catt!

My only question is: why would anyone bother building a coal plant, period, even in support of building Hoover or another wonder? At that point in the game, I at least never seem to have enough time to build a PP. There's always a unit to build...

[Catt]

Glad to participate and help . . . now stop the cheerleading!

WRT meltdowns, I didn't test the anarchy / meltdown possibilities directly, but always thought anarchy was a form of civil disorder and thus there was a chance for meltdown. I'll test it in my test scenario tonight just to be certain. Pending the resolution of that issue, a nuclear plant will not meltdown in periods of calmative order .

Hoover's does indeed rock. To be honest, I can't remember with clarity the last time I [i]didn't[i] manage to build Hoovers when it was available or the last time I actually felt the need to build a nuclear plant. But in the interests of completeness (since we all have different playstyles and victory conditions enabled) I added info on the nuclear plant.

I can remember (without much clarity) several games over the last few months in which I didn't build Hoover's because I did not have a river within my territory, anywhere. Even had a map with no rivers in the entire world! Makes you appreciate the dirty coal plants, the ridiculously expensive solar plants (which otherwise serve almost exclusively as SS parts pre-builds), and the availability of nuclear plants.

Originally posted by Yahweh Sabaoth
My only question is: why would anyone bother building a coal plant, period, even in support of building Hoover or another wonder? At that point in the game, I at least never seem to have enough time to build a PP. There's always a unit to build...

I prioritize factories immmediately and expect Hoover soon afterwards. Without Hoover I am likely to prioritize plants as well. For me at least, at that point of the game I am either peacefully widening my science / economic advantages and holding off for tanks before the next deliberate offensive (if there is one), or I am whipping an AI -- I find at that stage of the game I can pretty easily slip power plant builds into my production queues and still produce as many units as I need. The AI is pretty awful at Industrial Age warfare, and a slow grinder of infantry, some cavalries, and artillery does the job. Wars for me at that point are more about attrition than numerical superiority and the AI is, as I noted, very bad at the tactics of attrition warfare.

I've even found that with a less than decent pre-build for Universal Suffrage, it is oftentimes more efficient to switch the pre-build to a factory (and even lose some shields) and then restart US from scratch (sometimes a rushed coal plant is needed to make up the lost pre-build accumulation).

Catt

[Nakar Gabab]

Nuclear Plants are fun if you get to the Modern Age with a tech lead and rush to Robotics. Nuke plants in every city that can handle it plus manufacturing plants makes for a fearsome endgame indeed. You'll win easily (even behind on the space-race, that's how good your production winds up being), but it's still interesting. Mainly for cranking out unfathomable numbers of radar artillery in a couple of turns and pounding things into dust.

[Catt]

Originally posted by Catt
WRT meltdowns, I didn't test the anarchy / meltdown possibilities directly, but always thought anarchy was a form of civil disorder and thus there was a chance for meltdown. I'll test it in my test scenario tonight just to be certain. Pending the resolution of that issue, a nuclear plant will not meltdown in periods of calmative order .

Anarchy is not a form of civil disorder and will not, by itself, provide an opportunity for meltdown. So long as your cities remain sufficiently content during the anarchy, it appears that no meltdowns will occur. I have added clarifications to the initial posts.

Catt

[Yahweh Sabaoth]

What is the possibility of your brain suffering a meltdown while playing Civ? Does it increase with the amount of hours you play? Does the likelihood increase during periods of Emotional Unrest?

[Catt]

Originally posted by Yahweh Sabaoth
What is the possibility of your brain suffering a meltdown while playing Civ? Does it increase with the amount of hours you play? Does the likelihood increase during periods of Emotional Unrest?

Limited; yes; yes.

[Yahweh Sabaoth]

Thank you for the clarification.

[Master Zen]

If you have enough luxes or happyness wonders, building Nuclear Plants in your most productive cities is one of the smartest moves of the modern era. The extra 50% for factory production almost makes the effort of getting Manufacturing Plants moot. Plus, by that stage your big production cities can build one in like 4-5 turns, sometimes less so its pretty much a no brainer.

Some other power plant things I do:

- Never build Coal Plants since I always go for the Hoover Dam (and usually get it).

- Never build Solar Plants either.

BTW, getting the ToE is a surefire way of getting the Hoover Dam as you can beeline to Electronics instantly. It's best to already have a city producing something (Palace) so that you can get it as soon as possible in case you don't have a GL. It is also good to whore Atomic Theory and Electronics as most of the time the AI is slow to get them and you can get some major $$$ by doing so.

[King_Henry]

Thanks Catt! I just got to Industrialization in my game and your section really helped. I never knew Manufacturing Plants weren't considered plants. Now I'm not as confused.

[badman]

If I don't have a significant tech lead, I only build a coal plant in the city which will produce Hoover's, otherwise I won't build them at all since I really hate polluzion.

[CerberusIV]

It is worth building coal plants in a few cities even if going for Hoover (unless you have the luxury of a spare leader). I usually build 3, for US, ToE and Hoover followed by appropriate prebuilds for the wonders.

I often find the AI beats me to Industrialization by a few turns and even starts Universal Suffrage before I have the tech but the AI tries to build it in a city without a factory and 600 shields takes a long time that way. I can almost always overhaul an AI trying to build this wonder by prebuilding for a factory (with palace or military academy, even just a couple of turns on an expensive unit), build a coal plant and then go for the wonder.

It looks like a lost cause when you get a pop up that an AI has started Universal Suffrage and you are still 4 turns from industrialisation but is very satisfying when you can still snatch the wonder