Data are transmitted over a bus including a plurality of lines, wherein energy is dissipated as a result of data transmission. Preferably, the data to be transmitted in parallel are partitioned in a plurality of clusters of data bits. Each cluster is subject to re-ordering according to a set of reordering patterns to produce a corresponding set of respective candidate clusters of data bits. Crosstalk activity values related to transmitting the various candidate clusters are calculated and compared to identify an optimum cluster of data bits that minimizes the energy dissipated as a result of transmission by jointly minimizing the switching activity and the crosstalk activity. The optimum cluster of data bits so identified is then used for transmission over the bus. The optimum cluster of data bits thus causes those bits that give rise to high crosstalk activity to be allotted to bus lines having lower crosstalk capacitance values.