XFLEX Hydro

Alqueva is a pumped storage scheme in southern Portugal that was built in two phases, Alqueva I and II, now totalling 520 MW. The first station was operational in 2004 and the second commissioned more recently in 2017, each installed with two reversible Francis pump-turbines. At the site, the XFLEX HYDRO project aims to use hydraulic short circuit, extended operating range and smart controls to improve the flexibility provided to the grid – not only in terms of frequency services, but also voltage support.

View the video about the Alqueva demonstration.

Objectives

Evaluate low CAPEX opportunities to extend services offered by an existing pumped storage plant and compare them to a conversion to variable speed, namely:

Extended operating range targeting an almost continuous power output from near zero to rated power in generating mode;
Simultaneous pumping and generating through hydraulic short circuit operation;
Advanced joint control to adapt the dispatching rules according to optimisation criteria (efficiency, wear and tear, maintenance plan, etc.).

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Key Tasks

Initial studies
Database feed-in to the Alqueva demonstrator
Implementation of enhanced pumped storage plant (PSP) operation
Smart Power Plant Supervisor (SPPS) adaptation to enhanced PSP
Installation and operation
Conclusions

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Partners involved in this demonstration

full-scale apllications

During the project, the flexibility technologies will be trialled at 7 demonstration sites. These are located at existing European hydropower stations. Each XFLEX HYDRO demonstration site will test a different technological configuration, installed together with the Smart Power Plant Supervisor in every case.

BATTERY/ TURBINE HYBRID

Vogelgrun is a 142 MW run-of-river hydropower plant in France, situated near the border with Germany along the river Rhine.

ENHANCED FIXED SPEED

Alto Lindoso is a 630 MW hydropower plant situated on the Lima river in Portugal. Caniçada is a 70 MW hydropower plant located in northern Portugal

HYDRAULIC SHORT CIRCUIT

Alqueva is a pumped storage scheme in southern Portugal that was built in two phases, Alqueva I and II, now totalling 520 MW.

HYDRAULIC SHORT CIRCUIT

Sitting in the French Alps, Grand'Maison is Europe’s largest pumped storage plant at 1,800 MW capacity.

VARIABLE SPEED (DFIM)

Frades 2 is a new 780 MW pumped storage hydropower plant in northern Portugal.

VARIABLE SPEED (FSFC)

Z’Mutt is a pumping station located in Canton Valais, Switzerland, and feeds water into the main reservoir of the Grande Dixence hydroelectric scheme.