A considerable rise in the conventional trajectory of energy consumption is expected to be introduced by 5G which already consumes four times more energy than 4G. Consequently, energy efficiency is a major concern in 5G in contrast to earlier generations due to the further densification of cells. This paper proposes end-to-end power models for three different 5G RAN deployment architectures, namely the 5G distributed RAN, the 5G centralised RAN with dedicated hardware and the 5G Cloud Centralised-RAN. The end-to-end modelling of the power consumption of a complete 5G system is obtained by combining the power models of individual components such as the Base Station, the Core Network, front-haul, mid-haul and backhaul links, as applicable for the different architectures. The variation of the end-to-end power consumption of the 5G networks against key dependent parameters is analysed. The apportionment of power consumption at the different segments of the 5G networks is also calculated and discussed. It was found that the Decentralised 5G scenario had the highest power consumption of the three models analysed. On the other hand, the Centralised 5G and the 5G Cloud C-RAN consumed 12% and 20% less power respectively as compared to the Decentralised solution. Moreover, calculations demonstrated that the power consumption attributed to Base Stations varied between 74–78% of the Global 5G network power consumption. Thus, this study provides valuable insights for understanding the power consumption of various 5G architectures thereby laying the foundation for their sustainable deployment.