Most expensive hydropower dams

Some time ago I read an article about the Zungero hydropower dam (Nigeria). The article pointed that Nigeria people was concerned because the total cost of the 700 MW project was 1.3 billion $US; that is 1.87 million $US per MW; a price they considered to be excessive (the title suggested the most expensive in the world).

I compared the Zungero dam price with the price of the hydropower dam project Chepete (Bolivia) which is also a very controversial project, not only because of its cost but also because of its potential disastrous consequences and several observations about its feasibility. According to the executive summary, Chepete will have a cost of 1.92 billion $US per MW; more expensive than Zungeru.

However, it would not be fair to consider Chepete as the most expensive hydropower because of one single comparison. The following table shows a comparison of some of the most controversial mega hydropower dams. Once again, Chepete is the most expensive hydropower project in world.

Hydropower	Country	Power [MW]	Cost [B $US]	Power cost [M$US / KW]	Note
3 Gorges	China	22 500	37	1.64	Source
Itaipu	Brazil/Paraguay	14 000	19.6	1.40	Source
Belo Monte	Brazil	11 233	14.4	1.28	Source
Xiluodo	China	12 600	6.2	0.49	Source
Grand Ethiopia Renaissance	Ethiopia	6 000	4.7	0.78	Source
Baihetan	China	12 000	13.5	1.13	Source
Grand Inga	Congo DR	40 000	80	2.00	Source
Chepete	Bolivia	3 300	6.34	1.92	Source

There is a possibility that the Grand Inga Dam (Congo D.R.) may be more expensive (there is still not much data about this Mega project that would be the biggest hydropower dam in the world, with an installed power 12 times higher than Chepete).

It is important to note that the cost of Chepete considered only the construction cost reported by the respective studies. There are additional costs that will certainly increase the total cost of Chepete, for instance:

• Chepete will require a power transmission line longer than 1 000 km across the Amazonia.
• Chepete is located on the Beni river, a river with a very high sediment load; Beni river could be considered as a river among the 10 rivers with highest sediment load. Thus, it may have high maintenance costs that will increase the total cost.
• Big hydropower dams usually have high overcosts between 26% - 90% of the initial budget.
• Chepete will affect a very fragile ecosystem and the environmental costs may be expected to be high with several additional negative consequences,

Although this data is not enough for defining the single most expensive hydropower dam, we can assume with high confidence that Chepete would among the most expensive hydropower dams (if built).