The implementation of the much-delayed power development plan (PDP) may need to be further put back for a more careful revision to reduce long-term power supply in order to trim electricity bills, says the Thailand Development Research Institute (TDRI).
The PDP, set to take effect from 2024 to 2037, already sailed through public hearings held late last year but has yet to receive the final say from the National Energy Policy Council, chaired by Prime Minister Paetongtarn Shinawatra.
The plan must be reconsidered as it could lead to overinvestment in new power plant development projects, though the country's power demand may not increase considerably over the next 13 years, said Areeporn Asawinpongphan, a research fellow on energy policy at the TDRI.
It is not a good idea to push for the construction of 11 new large power plants -- eight gas-fired power plants and three hydropower plants -- in the PDP, she said.
This would bring an unnecessary financial burden to electricity users, she noted.
Thailand's power generation capacity in reserve stands at almost 38% of total installed capacity of 55,000 megawatts, Ms Areeporn said.
But the current electricity demand is much less than the supply, with consumption reaching 34,620MW during the peak period at 8pm on April 25.
The huge surplus of reserve is among the factors that can drive up electricity prices, said Ms Areeporn.
"The amount has been greater than 15%, which is the standard reserve, for more than 17 years," she said.
Another factor is availability payment (AP), which is an essential part of power purchase agreements the state electricity agencies made with power companies, she said.
Power purchase agreements, usually lasting for 25 years, commit the government to paying for electricity throughout the whole period, though the actual usage may be less during that time frame.
The AP increased to 55 billion baht last year, up from 49 billion baht in 2023.
The 55-billion-baht payment, or 0.34 baht a kilowatt-hour (unit), was added to the power tariff which rose to more than 4 baht a unit in 2024, said Ms Areeporn.
She asked the government to consider offering a longer power purchase period for power companies in exchange for a lower AP.
Kurujit Nakornthap, former permanent secretary for energy, said authorities must also promote direct power purchase agreements to enable businesses to directly buy renewable electricity from producers.
This would support the country's push for carbon neutrality, he said.