Winters are certainly over and it’s time to switch on the air conditioners as its getting hotter each day. But what I was thinking is that we use a heater to keep ourselves warm in winters and life without an air conditioner in the scorching summers is uneasy. As the temperature is keeping a positive slope these days, I find myself staring at the room heater and ponder about the cent per cent efficiency it delivers and being an electrical engineering student my mind questions that why do we need a room heater if we already have an air conditioner which performs the same work but in the opposite direction.

So I decided to share the information I got from various webpages on whether an air conditioner could actually be used as a room heater or not? The working of an A/C is simple; it pumps out the heat from indoors to the hotter surroundings. This tendency of doing work against the natural tendency (of heat flow from higher to lower temperature) is due to the electrical energy we supply. The more the difference in the temperature, the more electrical energy is needed and vice versa .

Ideally , to pump out a given amount of heat , we have to provide that much energy times a factor of

(T outside / T inside -1).

If we want to maintain an inside temperature of 20 Degrees with an outside temperature of 50 degrees then this factor is 0.102.

A 1 KW ideal A/C can pump almost 15 KW of heat flow out of the room an A/C with an efficiency of 40 % the number is 6 KW .

A total of 1+6 = 7 KW of heat is ejected into the atmosphere using 1 KW of electrical energy.

Imagine a room with an A/C installed inside out. The region to which it pumps the heat into is now the inside of the room. This is a super-efficient heater which has an efficiency of 700 % against the conventional 100% efficiency of the resistance type room heater .

It should be a sincere endeavour to make this ‘ not so new product’ commercially viable .

– Tarun, TIF

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