This gets a lot lower with differing latitudes and seasonal and daily cloud cover/evening time - closer to 100 W/m2 [1]. So over a day you'd get 2.4 kWh. In com

This gets a lot lower with differing latitudes and seasonal and daily cloud cover/evening time - closer to 100 W/m2 [1]. So over a day you'd get 2.4 kWh. In comparison an electric space heater uses about 1 kWh of energy in an hour. So how much will 2.4 kWh change the temperature of a cubic meter of water at the ocean surface? Density of water = 1000kg/1m3 so mass = 1000 kg 2.4 kWh = 8640 kJ Heat_Energy = Conductance * Mass * change_in_temp 8640kJ = 4.186 kJ/(kg⋅K) * 1000kg * xC x = 2C So solar heat will change the first meter of water by about 2C over the course of a day. That's a small number b/c solar radiation is not a huge contributer to temperature swings. Instead what will effect the temperature difference is the seasonal change. If we can calculate the heat energy gained or lost due to seasonal extremes and water temp, then we can figure out what the range of acceptable heat energy is for surface water. [1] https://www.withouthotair.com/c6/page_38.shtml https://www.withouthotair.com/c6/page_38.shtml ETA: logic.