COMPOSITE PLASTIC FOR THERMAL INSULATION OF STRUCTURES

Every day, a terrible amount of electricity is used for cooling the insides of the living area in a building, be it in form of air conditioners or a huge HVAC system. And this accounts for 17% of the national delivered energy and 19% on the total carbon dioxide emissions of our nation and is almost the same for all the tropical and sub-tropical countries. This not only pressurises the extended use of electricity, but also the pockets of middle class individuals. The need of cooling arises from the fact that masonry or concrete block walls absorb a high amount of incident solar radiations, and conduct it too to the inside. This results in increased heat content in the inside and subsequently increased loads on the air conditioning systems which in turn results in increased electricity use and increased bills. The problem occurs during night time also when the walls have absorbed heat, they tend to release it towards the colder end, which in most cases are the inside of the buildings. This further contribute to higher loads in terms of kWs on the AC compressor and thus further increase of expenditures on cooling alone. The concept lies in insulating a structure (residential or commercial), with the use of plastic sheets of nominal thickness (say, 8-10mm.) of extremely low thermal conductivity, which would cut down the two of three methods of heating i.e. radiation and convection. This would prevent the walls to absorb heat during day time and thus, lesser cooling costs. The idea serves dual purpose, the rst being lowering of electricity use would ultimately lead to saving of fossil fuels, the second, as it would be made from partly virgin and Municipal Solid Waste, it would help in lowering down of the plastic heap from the dump yards. It would be applied on the exteriors of the building walls, in form of 5ft*3ft sheet of thickness 8-10mm and thermal conductivity of the order of 10-1 W/m K or lower, which would be sufcient to resist inward ow of heat to the walls. Hence, no absorption of heat would mean no release of heat and thus cooler insides would directly have positive effects on the cooling costs.