No you cannot freeze the oceans, even with energy available from a billion nuclear fusion power plants because energy is conserved. If you want to freeze the oceans, you need to erect a reflecting umbrella between Earth and sun, but not on the night side. You cannot do it by producing and releasing more energy on earth. Here is why: The oceans have a large amount of thermal energy you need to transfer to some place. Conceivably you could build a zillion heat pumps and pull thermal energy out of the oceans and inject this extracted energy deep into the earth, but the thermal energy released by your nuclear power plants would be greater than the energy removed from the oceans so the oceans, air etc. would be growing hotter, not colder. This is the same reason one who knows the laws of thermodynamics* does not suggest fighting global warming with heat pumps by having their hot radiators radiate IR to space. Three inch tall humans, although very unlikely, is not AFAIK impossible and thus is more feasible than you magic solution. ------------- *It is probably way beyond your comprehension but for others and briefly: Consider two equal mass tanks of water at T > t temperatures. Average temperature = (T+t)/2. You could run a thermal engine between them and use the power generated to run a heat pump taking heat from the colder tank to restore the heat to the hotter tank. If there were no frictions and both operated at their Carnot limits you could just "break even." (Have a perpetual motion system) If any friction or either heat pump or the engine is not operating at the Carnot limit, then some external energy source is required and the average temperature will be increasing.