The Thailand Consumer Council (TCC) supports the Transport Ministry's plan to cap the fare on mass transit electric train services at 20 baht per trip, according to Saree Ongsomwang, TCC secretary-general.
She also suggests the ministry allocate a "fair" budget for public bus services in every province.
In an interview with the Bangkok Post, Ms Saree said the 20-baht electric train fare was among Pheu Thai's campaign promises made ahead of the election last year.
Former prime minister Thaksin Shinawatra also touched on the issue during his "Vision for Thailand 2024" speech.
He said the 20-baht cap could be achieved if the government bought back private electric train projects from companies.
The government could set the ticket prices and introduce congestion charges for car users, he said, adding the money could then be used to subsidise public transport.
"Setting the flat rate at 20 baht can definitely be done," Ms Saree said, adding that if it is successful, it will be an unprecedented reform of the mass transit system.
It was likely to win overwhelming support, similar to the 30-baht universal healthcare policy in the past.
She said when more people start using the mass transit system due to its affordability and convenience, those who now drive private vehicles will be more inclined to realise the benefits of using public transport.
They will eventually start using the electric rail service, which will contribute to a decrease in urban pollution, she said.
"Due to concessions granted by the ministry to private businesses for the construction and operation of some electric train lines, the government is now unable to fully implement the flat rate fare," she said.
"Commuters must pay varying fees while using different train services," she added.
"One passenger's round-trip fare from their home to their workplace may total between 100 and 200 baht.
"Many people would [rather] pay for their own car in instalments given this cost," she noted.
She said the TCC also researched the possible expenses of using an electric train service and found that the average cost per person would only be 16 baht for each journey if the admission fee--collected by electric train operators--is not paid.
"The 20 baht flat fare for the whole line is possible when every line is owned by the government," she said.
She said the ministry should consider reallocating funds intended for building expressway projects to fund the purchase of electric train concessions from private firms.
The ministry doesn't need to act quickly if a private company refuses to allow the government to purchase the concession back.
They ought to hold off until the end of the concession term. For example, the BTS Green Line concession's contract will expire in 2029.
However, if it's a different line -- such as the recently-introduced Yellow and Pink Lines -- the government should bargain with the companies to get them to sell their concession.
Ms Saree said the concession fee should be fair to the private sector as well.
Exploiting funds from vehicle registration renewal fees collected by the Land Transport Department is an additional method of determining a budget for buying back the concession.
Ms Saree said the department can bring in roughly 50 billion baht annually through this method.
The money can be used to buy back the electric train concession, she said, adding the money can also be used for procurement of public buses for every province.
"Bus purchases typically cost 6 million baht," she said.
"The ministry will need to spend almost 33 billion baht on 5,390 buses if it can buy 70 buses for each of the 77 provinces."
"More people will benefit if the funds are used in this way [rather] than if they were used to build an expressway," she added. "For example, the Expressway Authority of Thailand has a plan to create a double-decker highway project that will cost 34 billion baht."
She also said the government should pay greater attention to the demand for public transport in rural areas while big cities should consider putting a monorail project into action.
The capital city should have a more extensive secondary transport network, with more public buses and boats, to connect commuters to those electric rail services.
"Every government has an obligation to offer the most efficient, affordable and most convenient mass transit system possible," she said.
"If the government is successful in accomplishing this, the government will be able to collect money from the fee that private automobile [drivers] pay to enter the inner parts of the city, which would assist in reducing traffic congestion."
"All of this is done in accordance with the principle that people's daily travel expenses must not exceed 10% of the minimum wage," said Ms Saree.
Saree: Trains must be affordable