The Feasibility Study on Investment of Building Material Installation to Reduce the Electricity Cost From Air Conditioning Consumption

Abstract

This research aims to (1) study the use of a shading device to reduce electrical energy of air conditioners in classrooms at Phranakhon Rajabhat University, (2) determine the type of wall shading devices that helps reduce air conditioning electricity cost subjected to the principle of cost-effectiveness, (3) define the break-even point by comparing between the cost of shading devices installation and the reduced electricity cost, and The research was conducted in an air conditioned classroom located on the 3^rd floor of the Workshop Building 3, the Architecture program. The classroom is on the west side of the building with a size of 10.00 x 10.00 meters and a height of 2.90 meters from floor to ceiling. The research was conducted by comparing between installing a shading device to protect the classroom from the sun heat entering through a glass wall and no installation at all. The results were that (1) installing the shading device reduced the air conditioning electricity cost was reduced to an average of 13.40 baht per day, which is 3,537.60 baht per year or 8.40%, (2) the wall shading device suitable for reducing air conditioning electricity cost subjected to the principle of cost-effectiveness is ready-made horizontal wooden slat blinds which are fitting for all types of buildings, easy to install and has long period of use, (3) the break-even point was calculated by the price of the ready-made horizontal wooden slat blinds of 12,600 baht divided by the annual electricity cost of 3,537.60 baht, which resulted in the break-even point of 3.5 years.