An electrical machine is provided comprising a first rotor (121), wherein the first rotor includes a support structure (163), a second rotor (131), a stator (141) and, wherein the first rotor, second rotor and stator are arranged concentrically about a shaft (50), and at least one of the second rotor and the stator is adapted to accommodate the support structure. An electrical machine is also provided comprising a shaft (50) having an axis, at least one first rotor (321), at least one second rotor (331), at least two stators (341a), (341b) and, wherein the first rotor, second rotor and stators are arranged axially along the shaft and extend from the axis.