Because much of Switzerland has a mountainous landscape, I wonder if the tunnels would follow the terrain contours (and be at a constant depth relative to the surface) or they would avoid uphill/downhill sections by being at a constant elevation relative to sea level? Probably the answer is "neither" but I'm curious what the thinking is.
Looking at the map, it seems to be running mostly in the highly populated valleys. I guess the spurs are probably just tunneling under mountains (if they are underground, I doubt they would go up, the bigger problem is blasting through rock under the mountains).
This doesn't reach Alps, it stops at foothills of them (Luzern, Thun). Of course its not absolutely flat, but it will mimic existing regular speed rail system.
Due to it not being rail, it can tackle few steeper parts (ie uphill around Lausanne, that's solid 300m altitude difference). Lausanne subway (tiniest city in the world to have one) also uses rubber tyres on the section which goes straight uphill.
Swiss here. Not an expert on the project but AFAIK the idea is to reduce the impact of transportation on the surface.
With globalization and population increase, the need for point to point logistic is going to go through the roof in urban areas in the next years.
Currently this translates to having more trucks on the highways and roads, as our rail wail system is close to saturation already. Not to mention our road are really small compared to US (ie: highways are two-lanes per direction). This creates a ton of air and noise pollution and traffic jams.
This new transportation system should absorb some of the goods traffic and hopefully scale country-wide in the future while sparing the environnement at the surface as much as possible.
Assuming regenerative braking you can get much of the energy back again when the train goes down a hill. But your point broadly stands - for reasons like limited wheel/rail adhesion heavy trains and steep gradients seldom go together.
Depending on how the ‘stations’ work there maybe slopes up to them and then slopes down from them to help decelerate and accelerate the trains in and out of the stations