When it rains, where does the latent heat go? The latent heat of evaporation (or condensation) is absolutely huge. Condensation means heat is released. I did a back of the envelope calculation. 2 mm daily rainfall x 500 million km2 = 10^15 kg; each kg of water holds 2.26 MJ of latent heat, and there are 86400 seconds in a day, so that's 26.15 W, so overall 26150 TW. The Earth receives about 173000 TW from the Sun, so this is about 15% of the energy received from the Sun. Obviously, not all the 15% goes out to space, but about how much does go to space?