Plug-in hybrids (PHEVs) generally produce lower emissions than traditional hybrids, but the comparison depends significantly on how they are driven and the source of their electricity.
Emissions Comparison
Plug-in Hybrids (PHEVs):
- PHEVs can run in an all-electric mode for some distance, during which they produce zero direct tailpipe emissions, though they can still produce evaporative emissions.
- When the battery is depleted, the internal combustion engine (ICE) activates, producing tailpipe emissions similar to traditional vehicles.
- The overall emissions depend heavily on how often the vehicle is run in electric mode and the cleanliness of the electricity grid that charges the vehicle.
- Lifecycle emissions are reduced significantly compared to traditional petrol cars—typically by one-third to one-half, depending on electricity source and driving patterns.
- Battery manufacturing emissions for PHEVs are lower than full battery electric vehicles (BEVs), as PHEVs have smaller batteries (about one-sixth the size of BEV batteries), which further reduces total emissions over the vehicle’s lifetime.
Traditional Hybrids (HEVs):
- Traditional hybrids combine a gasoline engine with a battery that is charged through regenerative braking and the engine itself, but they cannot be plugged in to recharge.
- They produce fewer emissions than conventional gasoline vehicles because the electric motor assists the engine, improving fuel efficiency and lowering tailpipe emissions.
- However, they generally emit more than PHEVs because they rely mostly on the gasoline engine for power, especially over long distances or when the battery is depleted.
Summary
| Vehicle Type | Tailpipe Emissions | Electric Drive Capability | Battery Size | Lifecycle Emissions Impact |
|---|---|---|---|---|
| Traditional Hybrid | Reduced vs. conventional gasoline cars | No external charging; battery recharged by engine | Smaller battery, no plug-in | Lower than gasoline-only cars but higher than PHEVs generally |
| Plug-in Hybrid (PHEV) | Zero in electric mode; some tailpipe emissions when using gas | Can be charged externally and run on electricity | Larger battery than traditional hybrids but smaller than BEVs | Typically 30-50% lower than gasoline cars; can be slightly better than BEVs in some cases due to lower manufacturing emissions |
In essence, plug-in hybrids tend to offer lower emissions than traditional hybrids because they can operate in full electric mode for significant distances, reducing the use of gasoline. Their emissions advantage grows if they are frequently charged from a clean electricity grid and driven with an emphasis on electric mode. Traditional hybrids improve on pure gasoline vehicles but cannot match the emissions reductions achievable by PHEVs in optimal usage scenarios.
Overall, PHEVs combine benefits of electric driving with the backup of a gasoline engine, yielding substantial emissions reductions compared to traditional hybrids, especially in regions with cleaner electricity and for users who regularly charge their vehicles.
Original article by NenPower, If reposted, please credit the source: https://nenpower.com/blog/how-do-the-emissions-of-plug-in-hybrids-compare-to-traditional-hybrids/
