The World’s Largest Wind Turbine Has Been Switched On
The World’s Largest Wind Turbine Has Been Switched On
Caveat: I’m pro wind if it gets us off fossil fuels. It’s better than doing nothing and perfect cannot be the enemy of good enough (for now).
That said: in the late 1890s and early 1900s, scientists already knew about fossil fuels and greenhouse gasses and they didn’t speak up loud enough.
Take the idea of wind energy and project it’s growth a hundred years. From a pure physics perspective, when harvesting wind energy, you must steal kinetic energy from the wind. What happens when we’re harvesting say, 1% of all the kinetic energy of the atmosphere. Or 10%. Surely that will have major weather and climate effects. Or some far future anime sci fi outcome where we’ve captured 100% of the kinetic energy of the atmosphere and no air is moving except through turbines…
This turbine is very cool. What else should we be doing to prevent wind power from turning into the next generation’s climate disaster?
So, conservation of energy requires that if kinetic energy is removed from the wind, it must be converted to another form. If a building removes energy from the wind (through friction, flexing, transferring vibrations into the ground, etc.), that energy total must be equal to the kinetic energy lost by the wind. Thermodynamics says that any conversion of energy from one form to another results in some of that energy being converted to heat. So there’s some direct heating caused by the process of the wind hitting a building. That heat is largely heating of the air itself. After all, all those molecules had to collide with one another when they ran into the building.
The noise, vibrations, and other forms of energy conversion will all also end up as heat eventually, as they’re absorbed by the materials. So some indirect heating as well. In the ground, this is basically vibrations due a shuddering building being dampened by the material and turned into heat.
Now clearly on a windy day a building does not start significantly self-heating due to the wind hitting it. So the total amount of energy absorbed by a building cannot be that substantial. So, if one side of the equation (energy absorbed by building and converted into heat) is very small, then the energy removed from the wind must also be very small. Mostly the wind just changes direction to move around it.
I see what you mean but I don’t think your base assumption is correct. Energy can be transferred as well as converted to other forms, which is what happens to the vast majority of the energy removed from the wind in the case of it hitting the building It gets transferred to the ground, not converted.
If the wind hitting something converted all the kinetic energy to other forms rather than transferring most of it, the sail wouldn’t work for driving a ship for instance. Again, maybe I’m not catching what you mean here so I’m sorry if that’s the case. It’s true everything will eventually become heat, as in the heat death of the universe, but looking at the example of the building resisting the wind in isolation only a tiny fraction of energy ends up as heat rather than being directly transferred. I’m no physicist but that’s my understanding.