The oft-delayed power development plan (PDP) is expected to be completed within this year following a revision, said Prasert Sinsukprasert, energy permanent secretary.
Authorities need to revise key electricity generation issues in the PDP due to objections raised by energy analysts, though it sailed through a public hearing last year.
The government finished drafting the PDP, which is scheduled for implementation from 2024 to 2037, in May 2024, but the National Energy Policy Council (NEPC) has yet to provide final approval.
Energy analysts have requested adjustments to the PDP, which need to be considered before it is forwarded to the NEPC, chaired by the prime minister.
Experts want the government to determine an appropriate target for carbon dioxide emission reductions, as the new PDP promotes greater use of renewable energy, said Mr Prasert. They also want a more realistic projection of Thailand's electricity demand in the long term, he said.
Mr Prasert's comments were made as he presided over the 2025 Asia Sustainable Energy Week, which highlights energy technologies and solutions that promote clean energy. The three-day event got underway on Wednesday.
Under the PDP, total electricity generation in Thailand is expected to stand at 60,208 megawatts by the end of the plan, comprising 34,851MW from renewable power, 6,300MW from combined cycle power plants, which use gas and steam turbines to generate electricity, 600MW from thermal power plants or small modular nuclear reactors, 3,500MW from electricity imports and 2,000MW from other forms of energy.
The remaining 12,957MW would come from two types of energy storage technologies -- 10,485MW from battery energy storage systems and 2,472MW supplied by a pumped storage hydropower system.
Areeporn Asawinpongphan, a research fellow on energy policy at Thailand Development Research Institute, said earlier this version of the PDP could lead to overinvestment in new power plant development, though power demand may not increase considerably between 2024 and 2037.
This uptick in investment would raise electricity prices, driving up the cost of living for people, she said.
Another factor that caused a delay to the PDP enforcement involves what should be an appropriate renewable energy proportion set by the Energy Ministry.
The state's push for the second-phase renewable scheme with capacity of 3.6 gigawatts has been put back, following a dispute on criteria that gives a larger quota of renewable energy development to firms that failed to win renewables projects in an auction under the first phase of the scheme.
These companies have been allotted a greater share of capacity, amounting to 2.1GW of the total, while the remaining 1.5GW is available for new entrants, according to the criteria.