How Do Plug In Hybrids Work?

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PHEVs offer the best of both worlds: an electric motor and battery for some zero-emission driving but a gasoline engine to take over when the battery is depleted. So you won’t be stranded without a charging station in sight and a practical and flexible option for those who are hesitant to go full electric.

What Is A PHEV?

A plug-in hybrid electric vehicle (PHEV) combines ICE with an electric propulsion system. Unlike regular hybrids, PHEVs can be plugged into an external power source to recharge the battery so it can run on electric power alone for a certain distance. That electric only range means zero emission driving for short trips.

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PHEVs have a unique advantage: they can be charged from an external power source, like a home outlet or a public charging station. That means they can run on electric power alone for a certain distance, which is usually 20-60 miles depending on the model. That’s enough for most daily commutes and short trips and reduces fuel consumption and emissions.

When the battery is low, the ICE takes over, either powering the car directly or charging the battery. That dual power source means PHEVs don’t suffer from range anxiety, a problem with full electric vehicles (BEVs).

Plug-In Hybrid: Battery

The traction battery pack in a PHEV is the battery that stores energy for the electric traction motor. Modern PHEVs use lithium-ion batteries because of their high energy density and lightweight. The battery pack in a PHEV is smaller than a BEV but larger than a HEV. That intermediate size gives PHEVs a decent electric-only range and the flexibility of a gasoline engine.

PHEVs Electric Motor

The electric motor in a PHEV converts electrical energy from the battery into mechanical energy to power the wheels. PHEVs can be FWD, RWD or AWD depending on the placement and number of electric motors. Regenerative braking is standard in PHEVs, capturing kinetic energy during braking and converting it back into electrical energy to recharge the battery.

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Electric motors in PHEVs provide instant torque so acceleration is smooth and responsive. That makes the driving experience more enjoyable and PHEVs feel more powerful and agile than gasoline cars. And the quiet operation of electric motors makes for a more peaceful driving environment, especially during electric-only driving.

Charge Port & Onboard Charger

PHEVs have a charge port to connect to an external power source, just like how gasoline cars refuel at gas stations. The onboard charger converts the external current to a form suitable for the battery so charging is safe and efficient. Using an EV adapter, PHEV owners can connect to various charging stations with different plug types, ensuring compatibility and convenience. This is especially useful when traveling or when different charging stations use different standards. That means PHEV owners can charge their cars at home using a standard electrical outlet or at public charging stations.

Gasoline Components

In addition to the electric motor and battery, PHEVs have an internal combustion engine (ICE) that takes over when the battery is depleted. The ICE can power the car directly or charge the battery. That means PHEVs can go longer or when charging infrastructure is not available. PHEVs also have a fuel tank and exhaust system like a conventional gasoline car so it can run on gasoline when needed.

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The ICE in a PHEV is often optimized for efficiency with technologies like direct fuel injection, turbocharging and variable valve timing. That allows the ICE to produce enough power while minimizing fuel consumption and emissions. In some PHEVs the ICE acts as a range extender, running at an optimal speed to generate electricity and recharge the battery instead of powering the wheels.

Recharging Plug-In Hybrid Electric Cars

Most PHEVs can be recharged using a standard home outlet (Level 1) or faster Level 2 public charging stations. But since they have smaller batteries than BEVs, PHEVs don’t support DC fast charging. Level 1 chargers are suitable for overnight charging and provide a range of 2-5 miles per hour of charging, making them convenient for daily commutes. Level 2 chargers, on the other hand, provide a range of 10-60 miles per hour of charging, significantly reducing the time needed to recharge the battery. The ability to charge from an external source makes PHEVs more versatile and convenient for daily use, reduces dependence on gasoline and overall emissions.

Plug-In Hybrids vs. Other Electric Cars

PHEVs are the middle ground between BEVs and HEVs, combining the best of both worlds. Unlike BEVs which run solely on electric power, PHEVs can switch to gasoline when the battery is depleted and eliminate range anxiety. Compared to conventional hybrids (HEVs) PHEVs have a larger battery and can be recharged from an external source so it has a longer electric-only range and better fuel efficiency.

BEV Vs. PHEV

Battery-electric vehicles (BEVs) run on electricity only, no internal combustion engine. PHEVs have both an electric motor and an ICE so it can run on electricity for short distances and switch to gasoline for long trips. That makes PHEVs a flexible option for drivers who want to reduce emissions and fuel consumption without sacrificing range.

Hybrids Vs. Plug-in Hybrids

Conventional hybrids (HEVs) and PHEVs both use a combination of electric and gasoline power. But PHEVs have larger batteries and can be recharged from an external source so it can have significant electric-only driving. HEVs on the other hand rely more on their ICE and have shorter electric-only range so they can’t reduce emissions and fuel consumption as effectively as PHEVs.

HEVs are great for drivers who want to improve fuel efficiency and reduce emissions without changing their driving habits or investing in charging infrastructure. HEVs use regenerative braking and a small battery to assist the ICE so overall efficiency and performance is improved. But the limited electric-only range of HEVs means it still relies heavily on gasoline for most driving scenarios.

PHEVs have the best of both worlds, the benefits of electric driving for short trips and the flexibility of a gasoline engine for long trips. That makes PHEVs more versatile and can achieve more fuel savings and emissions reduction compared to HEVs. But PHEVs require access to charging infrastructure and commitment to regular charging to maximize the benefits.

Pros & Cons Of Plug-In Hybrids

Pros:

• Reduced emissions and fuel costs when driving in electric mode.

• Flexibility to switch to gas engine power for long trips.

• Federal tax credits and incentives.

• Lower running cost and maintenance compared to traditional gasoline vehicles.

• Quieter and smoother driving experience when in electric-only mode.

• Ability to use Level 1 and Level 2 EV chargers and various EV adapters for flexible charging options.

Cons:

• Higher cost due to larger battery and complex systems.

• Need for easy access to charging infrastructure.

• May not utilize electric mode if not regularly charged.

• Shorter electric range compared to battery electric cars.

• Dual powertrain systems may increase maintenance needs.

FAQs

• Hybrid or plug-in hybrid electric vehicle?

  A plug-in hybrid car is better for those who can charge regularly and want to maximize electric driving. A hybrid electric car is better for those who don’t have access to charging infrastructure.