Is preparing for photovoltaics in new construction sensible?

ok can the antenna cable from the Sat dish be laid through the same pipe?

Ideally separate data cable and power.

The routing of the power cables for the photovoltaic system should ideally be located beneath the photovoltaic area so that it is A) better protected and B) not visible. For this reason alone, a separation between SAT routing and photovoltaic routing already arises. Regarding the SAT dish, consider possibly laying power, LAN, and SAT (nat. + grounding with 16mm²) cables due to the weather station?

Hello, our photovoltaic system was installed the day before yesterday and yesterday. Do yourself a favor and size the empty conduits accordingly. We had only planned one M40 conduit for the system and now the dilemma is that 9 cables need to be routed. Currently, the cables are stuck somewhere in the conduit; they won’t move forward or backward. On Monday, the electrician will come back with two people and cable lubricant and try to pull the cables through. If that doesn’t succeed, the cable routing will have to run along the house wall, which of course would be a visual disaster. Therefore, my advice is one M60 conduit per side of the roof.

We have 2x40mm conduit for DC cables and a 25mm conduit for grounding/potential equalization.

ok can the antenna cable from the satellite dish be laid through the same conduit?

No, you are not allowed to do that. Actually, you need two conduits for the satellite dish. One for the antenna cables and one for the 16qmm lightning protection conductor. Otherwise, the separation distance according to DIN VDE is not maintained. This is very often done wrong in practice.