Rapid Bus has launched a proof-of-concept project to convert four diesel buses into electric vehicles (EV) in collaboration with two local firms, The Star reports, in an attempt to see if retrofitting is a viable alternative to buying a new fleet.
The trial, set to be completed by end-2026, reportedly involves buses with an average age of 11 years, and if successful, could extend the service life of older vehicles by up to seven years. Rapid Bus said in a statement that the aim is to cut capital expenditure and emissions.
Automotive engineer and Universiti Kuala Lumpur-Malaysia France Institute automotive engineering section senior specialist Haidee Che Rizmin told the English-language daily that this was akin to giving the buses “a new heart”.
“There are no issues with the buses’ chassis in terms of long-term service, but the powertrain systems will wear out over time and require a major overhaul after a certain mileage, and that will incur substantial costs. For Rapid Bus, this overhaul typically occurs at around 1,000,000 km or about 10 years of bus operation,” he said, adding that while a new diesel engine might match the performance of an electric conversion, the latter could save fuel and maintenance costs over time.
“Electrifying old diesel buses is a strategic approach for Rapid Bus, as it is about 30% to 50% cheaper than acquiring new electric buses. In addition, modern buses using Euro 5 diesel engines require more chemicals for exhaust after-treatment, which increases operational costs. Electric motors are also more environmentally-friendly than diesel engines,” Haidee said.
He went on to suggest a modular battery design, saying this allows manufacturers to adjust battery capacity as required. “I believe Rapid Bus requires about 250 km per charge to cover daily operations, which is comparable to a diesel-powered bus,” he said.
“The cost of electricity is also usually lower, or at least comparable to that of diesel fuel, since Rapid Bus will likely be charged commercial electricity tariff rates,” added Haidee.
Meanwhile, Malaysian Land Public Transport Fans chairman Zac Cheong told The Star that the initiative would accelerate Rapid Bus’ zero-emissions transition. “Waiting for diesel buses to reach the end of their life before replacing them with electric buses would take at least 15 years, given the regulations set by the Land Public Transport Agency (APAD),” he said.
APAD’s 2007 circular stipulates that stage buses reaching the 15-year age limit are eligible for up to two one-year extensions. Applications for the second extension must be substantiated by documents from bus manufacturers, financial institutions or Puspakom.
Cheong told the English-language daily that converting diesel buses to EVs would help reduce both air and noise pollution as well as extend their service life, generating more returns.
“While the retrofitting cost is a factor, it is likely far lower than purchasing a brand-new electric bus, allowing for a more rapid and cost-effective electrification of the entire fleet,” he said, adding that electricity costs are generally more stable and predictable than diesel prices.
“The government should also provide subsidies to help operators absorb the initial retrofitting costs, preventing them from being passed on to commuters,” said Cheong. See the road transport department’s (JPJ) ICE-to-EV-conversion guidelines here.
