The government is being urged to increase the proportion of renewable power generation to more than the target of 50% set in the power development plan (PDP), which is scheduled to be finalised in the second quarter of this year.
The increase, up from 10-12% of total power supply at present, is needed because Thailand is committed to achieving carbon neutrality, a balance between carbon dioxide emissions and absorption, by 2050, said Tanachai Bunditvorapoom, chief executive of SET-listed Absolute Clean Energy.
"Thailand has plans to reduce carbon dioxide emissions in the power sector, but similar efforts in other sectors are unclear, so the country needs to increase the target in the PDP," he said.
"This means the power sector needs to try harder to reduce carbon dioxide emissions."
Thailand announced in 2021 at the 26th UN Climate Change Conference in Glasgow it plans to seriously address climate change, striving to reach carbon neutrality, as well as a net-zero target by 2065.
A renewable power generation scheme was launched and is governed by the Energy Regulatory Commission (ERC).
The auction of renewable power development projects under the first phase of the scheme, with power generation capacity of 5.2 gigawatts, already took place.
The ERC wants to auction more projects this year under the second phase with a capacity of 3.6GW.
However, renewable power generated from these two phases may be insufficient to reach the goals announced in 2021, said Mr Tanachai.
Under the PDP, authorities propose the development of two nuclear power generation facilities, with a combined capacity of 800 megawatts.
Nuclear is considered a zero-emission clean energy source.
Support for nuclear power development remains patchy in Thailand and is likely to draw fierce opposition from locals and non-governmental organisations, he said.
Thailand is also promoting biomass- fired power plants because they can supply steady electricity, unlike solar and wind energy, which are considered intermittent sources of power because of uncertain weather patterns.
Yet biomass power can only partially replace electricity generated by fossil fuels such as gas, said Mr Tanachai.
Authorities are considering increasing the renewable power target to more than 50% to ensure Thailand can significantly cut carbon dioxide emissions, but some challenges remain, said Sarat Prakobchart, deputy director-general of the Energy Policy and Planning Office.
They need to consider the possibility of higher electricity bills, driven by costly renewable power, he said.
"Thailand may lose competitiveness if the country totally supports renewable power without considering its budget limitations," said Mr Sarat.
The PDP, which is intended for use from 2024 to 2037, is part of the national energy plan (NEP), the country's blueprint for energy management.
The NEP comprises the alternative energy development plan, the energy efficiency plan, the oil plan and the gas plan.
The state-run Electricity Generating Authority of Thailand is promoting renewable energy with a nationwide project for 15 floating solar farms with a combined capacity of 2,750MW.
The first floating solar farm is at Sirindhorn Dam in Ubon Ratchathani, with a capacity of 45MW.
This first solar farm commenced operations in 2021.