How does an electric generator work, what happens when the load is greater than it produces?

Question

Electronics

All good. With the beginning of summer, as usual, power outages began in our village due to forest fires and planned work. And under the whistle of the generator turbine, a lot of stupid questions began to appear in my head. Where does the excess energy that consumers do not have time to consume go? Let's say if the generator burns a bunch of fuel and produces 100k kilowatts. But consumers need only half, 50k kilowatts. The other half will just disappear somewhere, fly away somewhere? Or let's say the generator produces 100k kilowatts, but some car service will use all the welding machines with might and main and 150k kilowatts will be required for stable operation. What will happen then? The voltage will just drop, let's say from 220V to 170V, will the welding machines weld a little worse due to a drop in power? Those. the generator is purple how powerful the load is connected to it,

Answer 1

"Loading" the generator looks like an attempt to slow down its engine. Regulation occurs by stabilizing the speed (with a higher load, the throttle opens more) and changing the excitation voltage on the generator.
If the load exceeds the nominal value, the automation will work and turn off the load, or the generator will stall.

Answer 2

100k kilowatts - this will already be 100 megawatts, the letter "k" is superfluous.

Let's say if the generator burns a bunch of fuel and produces 100k kilowatts. But consumers need only half, 50k kilowatts. The other half will just disappear somewhere, fly away somewhere?

No, 100 kW is the maximum power. If they consume 50 kW, then the generator produces 50 kW and burns about half as much fuel (we will not go into details about efficiency).
Of course, at no load, some fuel will be consumed, but not much. Well, there is 1% or 5% of the maximum flow. When there is no load, this is called idling.

some car service will use all welding machines with might and main and 150k kilowatts will be required for stable operation. What will happen then? Just let the voltage drop from 220V to 170V

It's right here. So it will be. The generated power will be 100 kW, the consumed power will also be 100 kW, the current in the network will increase, and the voltage will decrease.
In reality, a welding machine does not consume that much power, and it is difficult to find a car service center that can consume 100 kW. But I understand that this is just an example.