  Dark Matter in Earth intersecting orbits can scatter off the electrons and
lose energy, and finally be gravitationally bound to Earth. Eventually they
lose enough energy and accumulate at the core. It is assumed that DM
annihilates/decays predominantly into Standard Model particles inside Earth.
The heat flux from these processes is compared with the experimentally measured
value of internal heat flux of Earth which is 44 TW. Assuming steady state
between capture and annihilation/decay, we put constraints on the scattering
cross section of DM with electrons as a function of their mass. For low mass
regions ($<10^{-2}$GeV), these constraints on leptophilic DM are better than
ones obtained from direct-detection experiments.
