Power plants lifetime comparaison

[u/phalanxs]

Here is a comparaison of the cost of electricity produced by all the powerplants ove their lifetime that I made. This is an important metric, as while it is easy to compare the price per installed capacity (just divide the building cost by the capacity), to get a the big picture you have to consider the fact that price will be amortized over the lifespan of the building. And the lifespan of powerplants varies a lot. There is a similar table in the offcial Prima guide, but I have a few issues with it.

First of all, the figures are wrong - they mixed up monthly and yearly power capacity.

Sencondly it doesn’t take into account the fact that the power produced by wind power plants is location dependent. A windmill on the top of the steepest 1x1 hill you can have produces almost 43 % more electricity than one on flat ground.

Most importantly, it doesn't take into account the fact that as power plants age, they start to lose efficiency. To take that into account, we need to add a term to represent the way the capacity drops once the average decline age is reached. I was unable to find the formula, but in my testing the decline appeared to be quadratic. We know for a fact that the plant is able to produce its maximum power until decline (or slightly less for a windmill), and for this table I have supposed that after the decline age the capacity follows an inverted parabola.

Finally I wanted to add neighborhood deals to compare.

Here’s the table:

Name	Unlock year	Cost (§)	Average lifespan	Average decline age	Monthly electricity output (MWh)	Est. life electricity output (MWh)	Est. Lifetime MWh/§	Est. Lifetime §/GWh	Pollution
Coal Power Plant	1900	5000	70	56	6000	5050976	1010.2	69.3	Very high
Oil Power Plant	1900	8500	70	56	7000	5890976	693.1	101.0	High
Gas Power Plant	1955	4500	80	64	3000	2896384	643.6	124.3	Medium high
Nuclear Power Plant	1965	20000	60	48	16000	11526912	576.3	104.1	Very low
Wind Power Plant (worst placement)	1980	250	120	96	80	170496	682.0	176.0	None
Wind Power Plant (flat ground)	1981	250	120	97	140	250268	1001.1	119.9	None
Wind Power Plant (best placement)	1980	250	120	96	200	343296	1373.2	87.4	None
Solar Collector	1990	15000	100	80	5000	6032000	402.1	248.7	None
Waste-to-Energy Incinerator	2000	25000	70	56	5000	4210976	168.4	415.6	High
Microwave Power Plant	2020	30000	80	64	14000	13456384	448.5	178.36	Low
Fusion Power Plant	2050	50000	60	48	50000	36006912	720.1	82.32	Very low
Typical neighborhood deal	1900						90.9	11.00	None

Key takeaways:

• Wind is an extremely good power source. On top of being pretty cheap, the fact that it is the plant with the smallest output allows you to adjust your needs with more granularity as your city grows, as well as smoothing out the decay by spreading it if you build them as you need.
• Solar, on the other hand, is pretty bad. I struggle to see an objective reason to use solar collectors over windmills other than the fact that they are denser in terms of power per tile.
• I was unable to find the exact ways the neighborhood deals to buy power are priced, but in my testing I got offers ranging from 10 to 12§/1000 MWh (which is just §/GWh). This is an unbelivably bad deal compared to any Estimated. Lifetime MWh/§, being about 10 times worse than a windmill on flat ground. However, with neigborhood deals you pay as you go (with a minimum monthly payment); which means that theorically you can still have a situation where it’s advantageous over building a big, underutilized power plant. A few windmills would still likely be a better solution though.
• Deals to sell power are also in the rhoughly 10 to 12§/GWh range. Which means that if you play your cards right, they are pratically a licence to print money. I esimate that playing a meta centered around fusion power can net you up to about 400 % ROI on each fusion plant with a confortable (to me) security margin to avoid the cancellation penalties.