IMF-weighted (normalised to the total mass in stars above 8 M_⊙) cumulative energy flow for the single star models with metallicity Z = 0.004 and no initial rotation with a background density of 500 cm⁻³. Additionally, the sum of the energy inputs from SN, stellar winds and an estimate of the photoionisation energy is shown (labelled ‘Star’), and the energy input excluding the photionisation energy (labelled ‘no ph’).