Refrigeration is the removal of unwanted heat from a specific object, substance, or space and its transfer to another object, substance, or space. The Removal of heat lowers the temperature and it may be done by use of ice, snow, chilled water or mechanical refrigeration. The invention of refrigeration has changed greatly since its initial development. Many factors of it has been upgraded and improved since it was first made.Salting food was a common preservation method before the invention of refrigerators, this was done because bacteria cannot survive in salt, so rubbing salt on food or covering it in a salt solution called brine can help keep meat and other foods from spoiling. Some people had the advantage of an icehouse to cool their food to preserve it, which was the earliest form of a refrigerator. After General Electric(company) produced the first electric refrigerator in 1911, only the richest people could afford the luxury of having this new invention in their homes. Other people used an icebox to preserve their food. Even this was a bit expensive since water had to be frozen, then the ice had to be cut, stored, and delivered. It wasn’t until the 1930s that Freon (chemicals used as refrigerant as a form of gas at room temperature and a liquid when cooled or compressed) was used in refrigerators. After World War II ,refrigerators were produced in mass quantities, making them affordable and widely available. They had new features like automatic defrosting and icemakers. Combination refrigerator and freezer units were very popular. Throughout the 1970s, 1980s and into the 1990s, environmental concerns over the use of Freon were debated and studied. Because of its estimated effect on the environment, the government put tight restrictions on the use of Freon in refrigeration equipment. Today, just about all households have a refrigerator. It saves time in preserving foods, and it is more convenient for our demanding lifestyles, and helps keep food safer for longer periods of time. Refrigerators have improved technologically, becoming more customizable and efficient. About 15% of the world’s electricity is used to drive refrigerating and air conditioning systems .How can we know how efficient our refrigerators are? Well, although the efficiency varies, There is a sign that comes with every refrigerator that must indicate how much energy is to be used. The estimated efficiency for a regular refrigerator is around 9-10 %. There are many energy transfers going on throughout the refrigeration process, The energy source is electrical power, which would then produce kinetic energy to work the pumps inside the refrigerator, which would circulate the refrigerant. This reduces the heat in the fridge, increasing the external heat. The wasted energy of the the fridge would be heat and sound. An environmental benefit is the technological development of refrigeration allows less energy to be consumed, the modern refrigerator consumes 2 or 3 times less energy compared to refrigerators in the 1990’s. Less energy consumed decreases the need of more power plants which then avoid environmental drawbacks such as devastation caused by oil extraction. However, there are also environmental drawbacks, as mentioned before the freon (chlorofluorocarbons) becomes a gas that is eventually released into the atmosphere, the gas contains chlorine which would break down molecules of the ozone layer, which protects earth from harmful sun rays. Refrigeration is an obvious contributor to global warming because it usually involves the use of electricity that was made by burning fossil fuels. However, manufactures that deal with refrigeration are now trying to cut down on environmental drawbacks, the “Environmental Protection Agency” has inputed new regulations which force the manufacturers to cut down on the use of freon and harmful chemicals in their products. The Environmental Protection Agency is pushing companies to use a refrigerant with less global warming potential which will contribute to the environment and amount of energy consumed.