One of the culprits is the progressive tariff, which means the more you use, the higher the rate you are charged.
The progressive tariff is implemented to reflect the increased cost of electricity production as demand rises. The searing hot weather saw electricity demand hit a new record on May 6, when Thailand consumed 34,826.5 megawatts.
So, consumers can expect more big bills this month as the progressive tariff takes its toll.
Although the separate tariff-per-unit for households was reduced slightly in April, this reduction will barely make a dent in bills as the progressive tariff kicks in due to surging electricity use.
Unsurprisingly, consumers are asking what exactly is the progressive tariff – and why is it leading to shockingly high electricity bills.
Initial calculation of the electricity production cost in Thailand is based on lower production costs. However, as electricity consumption increases, the cost of production also rises.
This will be reflected in the May to August electricity bills even though the 4.70 baht per-unit charge will remain unchanged.
The progressive tariff is as follows:
Category 1.1: Monthly consumption not exceeding 150 units:
Units 1-5 charged at 2.3488 baht per unit.
Units 16-25: 2.9882 baht per unit.
Units 26-35: 3.2405 baht per unit.
Units 36-100: 3.6237 baht per unit.
Units 101-150: 3.7171 baht per unit.
Category 1.2: Monthly consumption exceeding 150 units:
Units 1-150: 3.2484 baht per unit.
Units 151-400: 4.2218 baht per unit.
Units 400 and above: 4.4217 baht per unit.