As the name electric vehicle goes, an EV is powered by electricity, but exactly how does that work?
To put it simply, in each EV, there lies an electric motor that can quickly draw energy from its battery pack which stores the electricity. With the help of a transmission, the rotation from the electric motor will turn the wheels of the EV, allowing it to move along.
While we now know how electricity helps to run an EV, we should note that not all EVs are fully powered by electricity. Depending on the type of EV, electricity can supply from 10% to 100% of the total energy used for the full driving range of the car.
There are typically 3 types of EVs which are categorised based on the source of energy used to power the car: hybrid electric vehicle (HEV), plug-in hybrid electric vehicle (PHEV) and battery electric vehicle (BEV).
Regenerative braking is one distinctive feature that is present in all types of EVs. When the brake is being applied in an EV, its electric motor reverses and spins backwards. While this causes the wheels to slow down and brings the car to a stop, the electric motor can function as an electric generator (some may have a separate electric generator) at the same time, converting the kinetic energy in the motor to electricity that is to be stored in the battery pack. The regenerative braking system is particularly useful in city-driving since the brakes will be used more frequently. This energy generating process will likely add around 10% more range to the vehicle. Through a DC/DC converter, the high-voltage DC from the traction battery pack can also be converted to low-voltage DC and supplied to the auxiliary battery which uses the power to start the vehicle and run its other accessories.
As regenerative braking only charges the battery pack when the car brakes, it is insufficient to power the car entirely. In fact, a HEV obtains most of its energy from petrol and powers the vehicle like an internal combustion engine (ICE) car when the battery is depleted. Hence, a HEV contains the typical components present in an ICE vehicle such as the engine, exhaust system and gasoline tank as well.
Figure 1: Components of HEV (Graphic: Alternative Fuels Data Centre, U.S Department of Energy)
Similar to HEV, PHEV also has both an electric motor and an ICE. However, in addition to regenerative braking, a PHEV is able to recharge its traction battery pack using a plug-in charging equipment and obtain electrical energy directly from the grid. Thus, a PHEV will have larger battery pack to store more energy and power the car electrically for greater distances of up to about 50 km.
Figure 2: Components of PHEV (Graphic: Alternative Fuels Data Centre, U.S Department of Energy)
An onboard charger is required to monitor the state of charge and to communicate with the external charger, also known as EV supply equipment (EVSE). All traction battery packs can only be charged using DC. In the case where the EV is supplied with AC, the onboard charger helps to convert the incoming AC into DC to charge the battery.
Lastly, BEVs are pure electric vehicles that solely rely on electricity and their electric motor. Hence, it has the largest traction battery pack among all 3 types of EV. A BEV will need to be charged by an EVSE and the charging time of a BEV can range from 30 minutes to 6 hours depending on the capacity of the battery, onboard charger specifications and type of charging used.
Figure 3: Components of BEV (Graphic: Alternative Fuels Data Centre, U.S Department of Energy)
Since no petrol is involved in powering a BEV, it does not emit any waste gas and does not require an exhaust system. As such, BEVs can also be regarded as zero-emission vehicles (ZEV) if its source of electricity comes from renewable energy. Already, ZEVs are becoming the next trend for EVs with several countries setting ZEV targets to help reduce global emissions. Singapore can consider it as part of our next step to build a greener transport system.
The Singapore government has set the adoption of EVs to be a key target in its Singapore Green Plan 2030. To support this, Singapore is on its way to install 60,000 charging points across our island-state by 2030 and will have all HDB carparks in 8 towns decked with chargers in just 3 years' time.
As a charge point operator providing a full suite of services to help businesses and drivers transit to an EV future, Volt is well-positioned to support the EV related initiatives in the Green Plan. We have a wide range of AC and DC chargers to suit different charging needs, as well as our very own Volt EV Charging app for users to enjoy a seamless experience with us. We are rapidly expanding our charging network, so make sure you keep a look out for us!
As the name electric vehicle goes, an EV is powered by electricity, but exactly how does that work?
To put it simply, in each EV, there lies an electric motor that can quickly draw energy from its battery pack which stores the electricity. With the help of a transmission, the rotation from the electric motor will turn the wheels of the EV, allowing it to move along.
While we now know how electricity helps to run an EV, we should note that not all EVs are fully powered by electricity. Depending on the type of EV, electricity can supply from 10% to 100% of the total energy used for the full driving range of the car.
There are typically 3 types of EVs which are categorised based on the source of energy used to power the car: hybrid electric vehicle (HEV), plug-in hybrid electric vehicle (PHEV) and battery electric vehicle (BEV).
Regenerative braking is one distinctive feature that is present in all types of EVs. When the brake is being applied in an EV, its electric motor reverses and spins backwards. While this causes the wheels to slow down and brings the car to a stop, the electric motor can function as an electric generator (some may have a separate electric generator) at the same time, converting the kinetic energy in the motor to electricity that is to be stored in the battery pack. The regenerative braking system is particularly useful in city-driving since the brakes will be used more frequently. This energy generating process will likely add around 10% more range to the vehicle. Through a DC/DC converter, the high-voltage DC from the traction battery pack can also be converted to low-voltage DC and supplied to the auxiliary battery which uses the power to start the vehicle and run its other accessories.
As regenerative braking only charges the battery pack when the car brakes, it is insufficient to power the car entirely. In fact, a HEV obtains most of its energy from petrol and powers the vehicle like an internal combustion engine (ICE) car when the battery is depleted. Hence, a HEV contains the typical components present in an ICE vehicle such as the engine, exhaust system and gasoline tank as well.
Figure 1: Components of HEV (Graphic: Alternative Fuels Data Centre, U.S Department of Energy)
Similar to HEV, PHEV also has both an electric motor and an ICE. However, in addition to regenerative braking, a PHEV is able to recharge its traction battery pack using a plug-in charging equipment and obtain electrical energy directly from the grid. Thus, a PHEV will have larger battery pack to store more energy and power the car electrically for greater distances of up to about 50 km.
Figure 2: Components of PHEV (Graphic: Alternative Fuels Data Centre, U.S Department of Energy)
An onboard charger is required to monitor the state of charge and to communicate with the external charger, also known as EV supply equipment (EVSE). All traction battery packs can only be charged using DC. In the case where the EV is supplied with AC, the onboard charger helps to convert the incoming AC into DC to charge the battery.
Lastly, BEVs are pure electric vehicles that solely rely on electricity and their electric motor. Hence, it has the largest traction battery pack among all 3 types of EV. A BEV will need to be charged by an EVSE and the charging time of a BEV can range from 30 minutes to 6 hours depending on the capacity of the battery, onboard charger specifications and type of charging used.
Figure 3: Components of BEV (Graphic: Alternative Fuels Data Centre, U.S Department of Energy)
Since no petrol is involved in powering a BEV, it does not emit any waste gas and does not require an exhaust system. As such, BEVs can also be regarded as zero-emission vehicles (ZEV) if its source of electricity comes from renewable energy. Already, ZEVs are becoming the next trend for EVs with several countries setting ZEV targets to help reduce global emissions. Singapore can consider it as part of our next step to build a greener transport system.
The Singapore government has set the adoption of EVs to be a key target in its Singapore Green Plan 2030. To support this, Singapore is on its way to install 60,000 charging points across our island-state by 2030 and will have all HDB carparks in 8 towns decked with chargers in just 3 years' time.
As a charge point operator providing a full suite of services to help businesses and drivers transit to an EV future, Volt is well-positioned to support the EV related initiatives in the Green Plan. We have a wide range of AC and DC chargers to suit different charging needs, as well as our very own Volt EV Charging app for users to enjoy a seamless experience with us. We are rapidly expanding our charging network, so make sure you keep a look out for us!