Coulomb screening, in conjunction with a particle velocity distribution, enhances the rate of P‐Dfusion at extremely low temperature (≊1 eV). Therefore, this process will be much more significant in various geophysical and astrophysical situations than hitherto believed. As a particular case, we demonstrate, given an appropriately strong screening potential, thatp–Dfusion may provide a significant portion of the excess heat radiated by Jupiter.