What are the issues with heating water in a pan, and how can they be solved?

When water is heated in a pan thermal energy can be lost as it can pass into the air at the water’s surface and around the edges of the hob, thermal energy can be more directly passed from the hob into the water by using a pan with a wider base and a lid. Secondly, when water is heated in a pan, thermal energy can be used to heat the base of the pan alone. To prevent this the heating element can be placed inside the water, which is how an electrical kettle works