The heat flux from the ocean bottom is miniscule - between 17 and 31 mW/m^2. See the "m" in "mW"? That's milliwatts - thousands of a watt.

The solar flux is ~1.36 kW/m^2. The "kW" means "kilowatts". We get many tens of thousands times more energy from the sun that we do from the interior of the earth through the crust under the ocean.