Charging the way toward reduced tailpipe emissions with EVs, HEVs

HEVs are the alternative created with the aim of striking a balance between electric and internal combustion engine vehicles.

As the country continues to brave through the rainy season, people rely on raincoats and umbrellas to shield themselves from the rain. To maintain the efficiency of these waterproof surfaces, manufacturers use perfluoroalkyl and polyfluoroalkyl substances (PFAS)—synthetic chemicals that consist of a long chain of linked carbon and fluorine atoms.

One way to approach this problem is with electric vehicles (EVs), which do not emit greenhouse gases at their point of use. However, shifting to purely electric vehicles would be expensive due to their significant manufacturing cost, which is reflected by a similarly high price tag. They also have some downsides in terms of their battery life, range, and charging stations being less accessible than gasoline stations.

Hybrid electric vehicles (HEVs) are the alternative that was created with the aim of striking a balance between the advantages and disadvantages of EVs and internal combustion engine vehicles (ICEVs).

Powering forward

According to Dr. Jose Biona, an associate professor at the University’s Department of Mechanical Engineering who specializes in sustainable transport, HEVs have two drivetrain configurations: parallel and series. While all vehicles have a drivetrain—a set of interconnected components that transmit engine power to a vehicle’s wheels—in HEVs, the drivetrain allows the electric motor and the ICE to work hand-in-hand.

A parallel configuration lets both the ICE and electric motor operate simultaneously, allowing the ICE and electric motors to be smaller.

In comparison, only the electric motor gives the vehicle the power to operate in a series configuration. Here, the ICE instead powers a generator that is then used to charge the vehicle’s battery.

Additionally, some automobile manufacturers like Toyota manufacture their HEVs with regenerative braking capabilities. When braking, the vehicle absorbs kinetic energy created from movement, and with regenerative braking, an electronically controlled brake system uses this energy to charge the electric motor’s battery. This allows HEVs to charge their battery without the use of an ICE.

Highs and lows with hybrids

Prospective vehicle owners often do not consider purchasing an HEV due to their higher price compared to ICEVs. For long-term use, HEVs may be more practical due to their fuel efficiency, but this advantage is dependent on the everyday driving conditions the vehicle experiences.

Importantly, the fuel efficiency of the HEVs and ICEVs varies at different speeds and depends on whether the vehicle is starting, stopping, accelerating, decelerating, or cruising.

Biona explains that electric motors are far more efficient than ICEs, and since the ICE does not run the vehicle directly, HEVs with series drivetrains operate more efficiently. This is in contrast to ICEVs, which may operate with low efficiency in frequent starting and stopping conditions.

Therefore, in city driving conditions with plenty of traffic, it would be far more fuel efficient to use an HEV. However, the fuel efficiency disparity between HEVs and ICEVs is almost negligible in highway conditions since the engine is running at a near-constant speed.

Making the switch

As carbon emissions from ICEVs are on the rise, choosing low emission alternatives may also help mitigate air pollution concerns. In fact, some countries like Japan have incorporated HEVs into their mass transportation system. When consumers shift to using HEVs from ICEVs, carbon emissions may be reduced by up to 34 percent.

While other Southeast Asian countries—like Indonesia and Thailand—have already established EV manufacturing hubs, the Department of Trade and Industry (DTI) aims to promote EV use with the Electric Vehicle Industry Development Act (EVIDA). With EVIDA, DTI will evaluate the manufacturing and assembly of EVs and its other components, while also outlining the possibility of exempting EVs from mandatory number coding-schemes.

With this, the government encourages consumers to adopt HEVs and EVs as a more sustainable alternative to ICEVs. Amid soaring fuel prices, choosing electric alternatives might incur more savings in the long run.

Easing conditions

Living in an era of fluctuating gas prices, choosing EVs and HEVs over ICEVs seems like a reasonable and practical option. However, the use of EVs and HEVs in the country remains low, with the emission-free option having higher upfront costs and lacking charging infrastructure in most areas.

In the Philippines, government-initiated programs have only covered EVs in the transportation sector. By 2017, the Department of Energy’s (DOE) E-Trike Program aimed to replace over 100,000 local ICE tricycles with electric counterparts. However, due to limited charging stations and high procurement costs, many vehicle operators were reluctant to adopt the greener alternative, forcing DOE to stop the program and to halt the manufacturing of e-trike units in 2016.

Although e-trikes continue to operate in the country, some operators and drivers have expressed their concern about the financial challenges brought by the pandemic—requiring drivers to work for a boundary of P1,300 per day to cover vehicle costs.

To accelerate the use of EVs, electric alternatives must be made more accessible to low-income and middle-income households. As EVs and HEVs generally cost more than ICEVs, providing subsidies—such as free charging stations and purchase subsidies—can motivate more consumers to shift to EVs. 

While larger batteries allow for higher vehicle range, it is not the most economical option. Instead, infrastructure-focused solutions, such as increasing the availability of charging stations along highways, could allow EV drivers to go on long drives without worrying about running out of energy. Currently, local government units plan to deploy electric buses to reduce carbon emissions for short-distance travel.

As many countries are now looking into widespread adoption of HEVs, Biona believes that the Philippines is already falling behind. While more infrastructure is needed to support the demand of HEVs and EVs in the country, people can now purchase HEVs that are similarly priced with ICEVs and ride more e-trikes and e-jeepneys in the metro.

As more commuters shift to public transport during the pandemic, the government may use EVs and HEVs in transporting millions of Filipinos daily while mitigating the environmentally harmful effects of such operations.

Although HEV and EV use are widely sought solutions to reduce overall carbon emissions, walking and cycling are also emission-free ways to travel. In a society gasping for clean air, shifting toward a more sustainable transport system must be done soon before it is too late.

By Francesca Salting

By Krizchelle Wong

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