The generator is important to keep your population warm in Frostpunk. If you have no fuel, then it will stop and your population will go freeze to death. So that does not happen, if you can upgrade your generator.
There are three important settings for your generator: the Steam Level, the Range Setting and the Overdrive. The steam level provides a higher temperature that the generator radiates while the area means the rings around it. With overdrive you first heat the defined area by one more heat step.
If you want to upgrade your generator because it gets colder, then you have to research it. You can develop the following improvements:
Warmth rate = 1
Temperature rise = +1
Coal consumption = 6 coal per hour
With G.-efficiency 1 = 5 coal per pc
With G.-efficiency 2 = 4 coal per pc
Warmth rate = 2
Temperature rise = +2
Coal consumption = 12 coal per hour
With G.-efficiency 1 = 11 coal per pc
With G.-efficiency 2 = 10 coal per pc
Warmth rate = 3
Temperature rise = +3
Coal consumption = 18 coal per hour
With G.-efficiency 1 = 16 coal per pc
With G.-efficiency 2 = 14 coal per pc
Warmth rate = 4
Temperature rise = +4
Coal consumption = 24 coal per hour
With G.-efficiency 1 = 22 coal per pc
With G.-efficiency 2 = 20 coal per pc
** If the generator efficiency 1 then ensures that your generator consumes 10 percent less coal each time.
Build a workshop accordingly, you shouldn’t have more than one research facility. In the beginning you should target at upgrading your generator, if you don’t have that much coal yet. Therefore, build rather steam centers or heaters. You can heat small areas or your workplaces.
If you use overdrive, the generator can explode. This happens when the stress level, ie the red bar in the generator window, has reached 100 percent. When the generator explodes, the game is over.
The Overdrive setting does not consume extra fuel. Accordingly, you should heat it more often. It heats the defined area by an additional heat level. However, you can make the attitude more efficient through research - as well as the coal consumption of the generator.