"By-Pass Ventile" als S/S-Sanierungsmassnahme

[tono]

Liebe KollegInnen,

ich habe eine Anfrage bzgl. einer "neuer" Massnahme zur S/S-Sanierung erhalten (v.a. für Abstiegs- und Anstiegsrate), die in Norwegen erfolgreich umgesetzt wird. Gib's in der Schweiz sowas ähnliches oder gibt's Gedanken dazu? Hier unten die Anfrage:

One of the relevant flow ramping mitigation measures, also included in the European mitigation measure library (CIS guidance no 37, 2020),  are by-pass valves. In case you are not so familiar  with this measure - here is a link to a master-thesis in Norway about by-pass valves; https://ntnuopen.ntnu.no/ntnu-xmlui/handle/11250/2455586

There is also a series of management reports on how  to ensure a good opertion of them (but only in Norwegian), and a fact-sheet about by-pass valves (omløpsventil in Norwegian) as a good practise mitigation measure; Nr. 7-2016 Omløpsventiler

In my Hydropower database from Norway, we have revealed that 98 HP plants (mainly new small scale HP) have this measure installed. This includes also ca 30 large scale storage HPs in Norway like e.g. Trollheim, Alta, Meråker, Brattset, Driva, Rendalen (large scale RoR-diversion type), Stuvane/Borgund. Mainly HP in important national salmon rivers.

 The main purpose of the by-pass valves/tube is to ensure a gentle down ramping flow in case of accidental shut down of HP turbines (e.g. failure in the grid, lightening, og turbine -failure), but in principles this constructional measure is also relevant to by-pass part of the turbine flow during down ramping or up-ramping.

As far as I have understood, this measure is not part of the feasability studies to mitigate hydropeaking in Austria. What about in Switzerland - do you know if you have installed by-pass valves or other similar measures, or this could be part of a "mitigation package" in the future?  As I see it, this measure should normally not have major impact on peaking possibilites as the valve can ensure more gradual release of water during rapid up or down-ramping so that turbine  production can be either started/stoped within seconds while the flow through the valve can be gradually changes over minutes or hours......

Nice if you have some overview about this type of measure in Switzerland 

Besten Dank und liebe Grüsse

Diego