Plans call for raising the country's power reserves from 15% to 20% in a bid to bolster energy security, says Energy Minister Pongsak Raktapongpaisal.
Thailand had total installed capacity of 32,961 megawatts as of April, but actual or standby capacity is quite lower. Power demand is nearly 27,000 MW during the hot season and 24,000 to 25,000 MW during the rainy and cool seasons.
Mr Pongsak noted that frequent supply disruptions of natural gas from Myanmar pose a risk of blackouts and brownouts.
From 2008 to April of this year, gas supply from Myanmar was disrupted 18 times, usually during the hot season.
Myanmar gas accounts for a quarter of overall natural gas demand, and a disruption could cut power reserves to 6% from the normal 15%.
"Without collaboration between the private and public sectors to cut working hours and implement energy-saving measures, we could have experienced blackouts or brownouts" during the April disruption, said Mr Pongsak.
The Electricity Generating Authority of Thailand's capacity totals 15,000 MW, with private producers adding 15,557 MW. Imports amount to 2,104 MW from Laos and 300 MW from Malaysia.
Mr Pongsak said Thailand has learned from Japan's crisis, when the Fukushima Daiichi nuclear power plant and others were shut down after the 2011 tsunami.
Nuclear, at that time, was a significant share of Japan's power generation, but economic activity continued because reserves were as high as 50%.
"For the first stage, power reserves should increase to 20% before incremental steps are taken to ensure that Thailand has enough security for the sector," said Mr Pongsak.
He declined to say what the maximum power reserve should be.
Mr Pongsak will also review the power development plan (PDP) this year, bearing in mind the government's infrastructure investments such as high-speed rail.
"Just one high-speed train line will drive electricity demand by an additional 1,200 MW. Due to urbanisation, power demand will also rise," said Mr Pongsak.
The Energy Policy and Planning Office is revisiting the PDP for the period of 2013-30.
The PDP was revised last year on the assumption that only 10 new mass transit rail lines would be built in Greater Bangkok, while high-speed trains and water management projects were not included.