Video broadcasters currently envision to target a variety of receiving devices of different resolutions. In such a heterogeneous TV network the transport resource consumption is likely to increase as the types and number of receiving devices increase. We estimate the required capacity for an IPTV and mobile TV network taking into account parameters as currently proposed in standardization bodies. The consumed transport capacity fluctuates over time for two reasons. First, as we target constant video quality as much as possible, the video is encoded in variable bit rate. In order to characterize the fluctuations of the bit rate associated with one channel we have encoded a representative set of video clips. Second, the user behavior causes the transport capacity demand to fluctuate because we consider a multicast-based transport system where only the requested channels are transported. We compare two modes for transporting TV channels in multiple resolutions: a mode based on the Scalable Video Coding (SVC) where all video resolutions are embedded in one stream and a simulcast (SIM) mode where all resolutions are offered in parallel. We evaluate in some realistic examples which of the two effects is dominant, i.e., the bit rate penalty of SVC or the fact that SIM transports the video streams in parallel rather than embedding them in one stream as SVC does.