PVs offer enormous potential to building designers but, as an architect has said, “it has to be done right from the start” – they should not be an afterthought. PVs can influence the building’s orientation, footprint, layout and form; they will affect the building fabric and will be an important element of the environmental and building systems. They need to be considered as an integral part of the energy strategy of the building and of its functioning. The integration of PVs with the other building elements is critical to success. Appearance and aesthetics are, as ever, especially important.