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A hydro plant at 5000m? That's a long way up!

https://electrek.co/2023/03/16/this-hyd ... sea-level/

2.2 GW.

EDIT - Also a capacity factor of 37.8 %.

Also it says it integrates solar and storage at the same site, which is interesting.
You'd think with such a high elevation they could make it into a really mahoosive pumped hydro scheme with a lower lake much lower down?

dan_b wrote: ↑Sat Mar 18, 2023 11:57 amAlso it says it integrates solar and storage at the same site, which is interesting.
You'd think with such a high elevation they could make it into a really mahoosive pumped hydro scheme with a lower lake much lower down?

It's in the Tibetan plateau, so the available drop might be quite limited. It's also a very long way from anywhere with a high capacity factor, both making pumped storage harder. Probably not worth the aggrevation.

Altitude is fairly meaningless without knowing the head.

I visited the Grande Dixance dam a number of years ago which has a head of over 1800m. Is that still the highest in the world?

There must be some kind of practical limit to the pressure that can be managed on these projects. 1800m gives about 180 bar pressure or 540 tons per square meter. A bit of blue pipe won't cut it with these pressures!

From Wikipedia

The water travels down a long penstock from the Grande Dixence Dam before reaching the Bieudron Power Station 1,883 m down. The water spins three pelton turbines, generating a combined capacity of 1,269 MW.The power station was built between 1993 and 1998 at a cost of US$1.2 billion.

The Bieudron Power Station alone holds three world records, for the height of its head (1,883 m), the output of each Pelton turbine (3 × 423 MW) and the output per pole of the generators (35.7 MVA). It was taken out of service in December 2000 after the rupture of a penstock. The power station became partially operational in December 2009 and fully operational in 2010.

So two years after it was built, it was taken out of service for 9 years. Obviously a 1,883m head presents engineering challenges

There are two other power stations supplied from Grand Dixence. An old small one with a head of 1,745m and an intermediate sized pair which first goes to power station half way down and then to a second one at the bottom.

I visited the dam in 2015.

I'm surprised they state a penstock for holding back the static head ? I would expect that to be the realms of a specialist control valve like the larner johnson.

Moxi

Moxi wrote: ↑Tue Mar 21, 2023 2:10 pm I'm surprised they state a penstock for holding back the static head ? I would expect that to be the realms of a specialist control valve like the larner johnson.

Moxi

The pressure pipe on a hydro scheme is called the penstock, as opposed to penstock valves.

One of the more interesting hydro valve arrangements is at Dinorwig with the rapid closing valves and surge shaft.

smegal wrote: ↑Tue Mar 21, 2023 5:03 pm

One of the more interesting hydro valve arrangements is at Dinorwig with the rapid closing valves and surge shaft.

So that is what the smaller pond is half way down and south of Elidir Fach, to reduce the hammering effect when the valves close?

openspaceman wrote: ↑Tue Mar 21, 2023 6:07 pm

smegal wrote: ↑Tue Mar 21, 2023 5:03 pm

One of the more interesting hydro valve arrangements is at Dinorwig with the rapid closing valves and surge shaft.

So that is what the smaller pond is half way down and south of Elidir Fach, to reduce the hammering effect when the valves close?

I don't know the pond itself, but I'd assume so. I just searched YouTube and saw a video where the valves closed super fast.