*3.4.3 Discussion*

To sum up, huge amount of money can be saved if such technique is implemented. In case that this system is applied to only 100 km road, total annual saving becomes about \$117,119.24; total saving in 50 years becomes \$5,855,961.75. It means that such system saves huge amount of energy and hence expenditure saving that can be utilized in other projects' investment. From is discussion, it is also possible to calculates the "Saving Norm" for the proposed system to be \$1171.19/km/Year (Eq. (3)).
