Which electric heater has a higher power rating?

The 4 kW electric heater has the highest power rating among the options provided. Power rating, measured in kilowatts (kW), indicates the amount of electrical energy the heater can convert into heat energy per hour. A higher power rating typically means the heater can produce more heat in a given time period, making it more effective at warming up a space quickly or maintaining a higher level of warmth.

In this case, the 4 kW heater can generate significantly more heat compared to the other options, which include 1.5 kW, 2 kW, and 3 kW heaters. Each of those has lower power ratings, meaning they will generate less heat energy than a 4 kW heater can in the same duration. Thus, the higher the kilowatt rating, the more energy the heater utilizes to produce heat, resulting in potentially higher efficiency and faster heating capabilities.