The popularity of compressed natural gas (CNG) as an alternative fuel is fast fizzling out.
From a peak of about 5,400 vehicles that ran on CNG in 2010, the population has dwindled to 4,400 as of the end of last month.
The Land Transport Authority said close to 1,000 owners of CNG vehicles have had their CNG kits removed since 2011. By doing so, the owners pay the Government a pro-rated tax rebate that they enjoyed when they first bought the vehicle.
One such owner is taxi operator Neo Nam Heng, whose Prime Taxi had more than 400 cabs running on CNG not long after the firm was set up in 2007.
"Almost all (the CNG kits) have been removed," Mr Neo told The Straits Times last week.
"We paid back millions of dollars in taxes, but it's worth it. We now have less down time, fewer repairs and less headache."
Mr Neo said his CNG-converted taxis had "a lot of maintenance problems".
Another taxi operator, Trans Cab, has also fallen out of love with the gas, which is deemed to be more environmentally friendly than diesel. Its managing director, Mr Teo Kiang Ang, opened the world's biggest CNG refuelling station near Jurong East five years ago.
But less than one-third of his 4,500-strong fleet of CNG cabs are on the roads now and Mr Teo expects none will be around in another two years or so.
He has applied for a change of use for his 7,066 sq m station site in Old Toh Tuck Road, but has not received approval yet.
He said he may build a new company headquarters there, but observers said he may convert it to a diesel refuelling station.
"Any business opportunity, I will consider," Mr Teo said.
He attributes the dwindling interest in CNG to several factors, including a multitude of restrictions imposed on the transportation and storage of CNG that has made the setting up of new stations less viable.
He noted that CNG car owners have also been largely disappointed with their vehicles.
There are now about 2,150 CNG passenger cars in Singapore, compared with 2,500 diesel cars. Back in 2010, the respective numbers were 2,706 and 138.
Other industry watchers said a government duty imposed on the fuel from January 2012, and the replacement of the previous Green Vehicle Rebate with a carbon- based incentive scheme also sealed the fate of CNG.
Motorist Melvin Toh, 31, who once drove a Honda Civic that could run on CNG, said he switched because he has since started a family and needed a car with more boot space. The CNG kit includes a sizeable gas tank placed in the boot, taking up, on average, half the available space.
The finance manager said that even when he had the CNG car, he was running on petrol "75 per cent of the time" because it was more convenient. "I don't live near a CNG station," he said.
There are only three CNG stations accessible to the general public: in Old Toh Tuck Road, Serangoon North Avenue 5 and Mandai Link. The last one, run by Smart Energy, now sells diesel as well. Around half its 18 gas pumps have been turned into diesel dispensers. Its managing director, Mr Johnny Harjantho, said this was "to supplement income".
But Mr Harjantho, whose now-defunct Smart Taxis once had 200 CNG cabs, said: "I believe if the price is right, there is still substantial demand for CNG."
When The Straits Times checked last Thursday, his station was retailing CNG at $1.76 per kg after discount, compared with around $1.80 and $1.46 for a litre of 92-octane petrol and diesel after discount.
Although a kilogram of gas is supposed to offer 20 per cent to 25 per cent more mileage than a litre of petrol, its real-life efficiency often falls below that, say drivers.
This article was first published on Oct 13, 2014.
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