This for example: https://upload.wikimedia.org/wikipedia/commons/b/b6/Cataratas.jpg
If you don’t want to click the link, it’s the Iguazu Falls, Argentina and Brazil Border.
It’s basically a huge waterfall. To my understanding, it generates enormous amount of potential power, meanwhile every water power station I’ve seen is either flow of river or a dam. Could we not put a water wheel next to the waterfall or something?
In: 1
The reason we build dams – and you absolutely could build a dam to exploit the height difference here – is to force the water into a chokepoint to maximise the amount of energy we can get out of it. Similarly building a reservoir at the top means that we’ve got some leeway: We’re not reliant on the natural flow of the waterway, but instead have a nice big pool we can manage the level of so that we can switch on the power generation as and when we need it.
Yes. You could divert some of the flow and send it through a turbine. There’s two massive hydro dams at Niagara Falls, called the Sir Adam Beck Hydroelectric Generating Stations, and they produce a significant amount of Ontario’s hydropower.
You can, but in practice you usually just divert the river flow into a hydroelectric station built next to the waterfall. And we do in fact do this on most large waterfalls – most notably Niagara Falls, which only continue to flow because local law requires them to leave some water to go over the falls rather than using all of it for power.
I am from Brazil and visited Iguaçu Falls (Brazilian spelling 😉 several times. It is an absolutely awesome sight in person.
Anyway, not far from there is the Itaipu Hydroelectric Dam, which is pretty much the result of doing just that to a waterfall that used to exist in that place, called Sete Quedas (Seven Falls). It was the largest Hydro in the world for several years, until it was surpassed by one in China.
The project dammed the Paraná River, creating the Itaipu Lake and submerging the falls, which can no longer be seen. The River now flows through 20 turbines, generating almost 80 TWh per year and supplying electricity at low cost to pretty much the whole South and Southeast regions of Brazil, where most of the country’s industrial base is, as well as covering most of the electricity needs of Paraguay.
If you go to the area, you can visit both Itaipu and Iguaçu Falls on the same day, and there is a lot more to see as well.
It’s not conceptually difficult. Dredge or blast a channel a ways upstream, where the river channel is deeper. Then build a penstock and a pipeline overland to the bottom of the falls. Build a powerhouse some ways below the falls on a location where erosion isn’t a big concern.
Because waterfalls are naturally prone to heavy erosion, you wouldn’t want to make use of the falls themselves. Nevermind the issues with constructing turbine works in the path of the falls. That would probably require flow to be diverted around the falls anyway Merely the fact that you have a large source of water travelling over a rapid drop in elevation is what you care about with regards to hydropower.
The downside of this is that if there’s a drought and the river flow becomes low enough, you can either stiff your electricity customers and say “sorry, power will only be on 8 hours of the day, or you run the risk of needing to bypass all the river flow around the falls and shutting them off completely.
Latest Answers