Electric cars and hybrids are not the same thing, and how they power themselves changes what breaks, what costs money, and how you drive them

A hybrid vehicle has two engines: a petrol engine and an electric motor that work together. The petrol engine runs most of the time. The electric motor kicks in during acceleration or when you need extra power, and it also captures energy when you brake to recharge the battery. A fully electric car (EV) has only an electric motor and a large rechargeable battery—no petrol engine at all. The difference matters because it changes what you maintain, how far you can drive on one charge, how long refuelling takes, and what happens when the battery gets old.

Key Takeaways

  • Hybrids use a petrol engine as their main power source and an electric motor as backup, so they still need oil changes and petrol fill-ups like traditional cars.
  • Electric cars run entirely on battery power, produce zero tailpipe emissions, and need no oil changes, but require access to a charger and take longer to refuel than petrol cars.
  • Hybrid batteries are smaller and last the life of the vehicle in most cases, while electric car batteries degrade over time and may need replacement after 8 to 15 years depending on use and climate.
  • Electric cars cost less to run per mile because electricity is cheaper than petrol, but the upfront purchase price is higher than a comparable hybrid or petrol car.
  • Hybrids work well for people who drive mixed distances and cannot install a home charger; electric cars suit people with predictable daily routes and access to charging infrastructure.

How a hybrid engine switches between petrol and electric power

In a hybrid, the petrol engine and electric motor are connected through a transmission system that decides which one does the work at any moment. When you start the car or drive slowly in traffic, the electric motor often runs alone—this is why hybrids are quieter in stop-and-go driving. When you accelerate hard or climb a hill, both engines work together to give you the power you need. When you brake, the electric motor reverses and acts as a generator, turning the kinetic energy of the slowing car into electricity that charges the battery.

The battery in a hybrid is much smaller than in an electric car—typically 1 to 2 kilowatt-hours compared to 40 to 100 kilowatt-hours in an EV. Because the petrol engine is always there to recharge it, the hybrid battery never fully drains. This is why hybrid batteries rarely fail and usually last as long as the car itself. You never plug a hybrid in; the petrol engine does all the charging work.

How an electric car's battery and motor work

An electric car has one large battery pack, usually mounted under the floor, and one or two electric motors (one per axle in all-wheel-drive models). When you press the accelerator, electricity flows from the battery to the motor when ready—there is no gear shifting or engine cranking. The motor is straightforward: it has no oil, no spark plugs, no timing belts, and almost no moving parts compared to a petrol engine.

The battery is the expensive and complex part. It is made of hundreds of individual cells wired together, and it stores chemical energy that converts to electrical energy. As you drive, the battery discharges. When you plug in, an onboard charger converts AC power from the wall (or DC power from a fast charger) back into the chemical energy the battery needs. Unlike a hybrid battery, an EV battery does degrade over time. Most manufacturers may provide the battery will retain 70 to 80 percent of its capacity after 8 years or 100,000 miles, whichever comes first. In practice, many batteries last longer, but replacement can cost £4,000 to £15,000 depending on the car and the battery size.

Charging an electric car versus filling a hybrid with petrol

Filling a hybrid with petrol takes 5 minutes at any petrol station, just like a traditional car. An electric car requires a charger, and the time depends on which charger you use. A standard 3-pin household socket charges at about 2 to 3 kilowatts and can take 24 to 48 hours to fully charge a large battery. A dedicated home charger (7 to 22 kilowatts) takes 4 to 10 hours. A public rapid charger (50 to 350 kilowatts) can add 200 miles in 20 to 30 minutes, but these are not available everywhere and often cost per use.

This difference shapes how you use each car. A hybrid works like a petrol car—you can drive 400 miles, stop for 5 minutes, and drive another 400 miles. An electric car works best if you have a charger at home or work, because you start each day with a full battery. If you rely on public chargers, long trips require planning and patience. Most electric cars have a range of 200 to 300 miles per charge, which covers most daily driving, but not all.

Maintenance and repair costs: electric versus hybrid

A hybrid still has a petrol engine, so it needs oil changes, air filter replacements, spark plug service, and all the traditional maintenance a petrol car requires. The electric motor adds almost nothing to maintenance because it has no wear items. The hybrid battery itself rarely needs service. Over the life of the car, a hybrid's maintenance cost is similar to a petrol car's, perhaps slightly lower because the electric motor handles some of the braking work and reduces wear on the brake pads.

An electric car has no oil, no spark plugs, no timing belt, and no transmission fluid. Brake pads last much longer because regenerative braking (the motor acting as a generator) does most of the stopping work. The main maintenance is tyre rotation, cabin air filter replacement, and coolant for the battery thermal management system. The battery itself is sealed and requires no user maintenance. If something goes wrong with the battery or motor, repair costs can be high because the technology is specialized, but failures are rare in modern electric cars.

Over 10 years, an electric car typically costs 30 to 50 percent less to maintain than a petrol car, and a hybrid costs about the same as a petrol car. However, if an electric car's battery fails outside the warranty period, the repair bill can wipe out those savings in one event.

Running costs: electricity versus petrol

Electricity costs roughly one-third to one-half as much as petrol per mile driven, depending on local electricity prices and petrol prices. If you charge at home on a standard tariff, you might pay £0.03 to £0.05 per mile. Petrol costs roughly £0.10 to £0.15 per mile. Public rapid chargers are more expensive than home charging but still cheaper than petrol. Over 100,000 miles, an electric car can save £3,000 to £8,000 in fuel costs compared to a petrol car.

A hybrid sits between the two. Because the electric motor handles low-speed driving and captures braking energy, a hybrid uses 30 to 50 percent less petrol than a comparable petrol-only car. You still buy petrol regularly, but less often. A hybrid's running cost is lower than a petrol car's but higher than an electric car's.

Which one makes sense for your driving pattern

Choose a hybrid if you drive a mix of short and long distances, cannot install a home charger, or need the flexibility of petrol refuelling. Hybrids work well for people who take frequent long trips, live in areas with poor charging infrastructure, or want to avoid the upfront cost of an electric car. You get better fuel economy than a petrol car without the range anxiety or charging logistics.

Choose an electric car if you have a predictable daily driving pattern (under 200 miles most days), access to a home charger or workplace charger, and live in an area with public charging infrastructure. Electric cars make the most sense for urban and suburban driving, where most trips are short and you can charge overnight. If you take frequent long road trips and charging stations are sparse in your area, an electric car will frustrate you.

Battery degradation and replacement: what to expect

Hybrid batteries are small and rarely fail. Manufacturers typically warranty them for 8 years or 100,000 miles, and most last the life of the car. If a hybrid battery does fail, replacement costs £1,500 to £3,000, which is expensive but not catastrophic.

Electric car batteries degrade predictably. They lose about 2 to 3 percent of capacity per year in normal use, faster in hot climates or if you regularly fast-charge. After 8 years, most EV batteries retain 85 to 95 percent of their original capacity—enough for normal driving, but noticeable on long trips. Manufacturers warranty batteries for 8 years or 100,000 to 150,000 miles (depending on the brand), guaranteeing at least 70 percent capacity. If you need a replacement after the warranty expires, costs range from £4,000 to £15,000. Some owners keep their cars for 15 to 20 years and accept the battery degradation; others sell or trade in before the battery becomes a concern.

Frequently Asked Questions

Can I charge a hybrid at home?

No. Hybrids do not plug in. The petrol engine charges the battery automatically while you drive. You only need to fill the petrol tank at a petrol station, just like a traditional car. Some plug-in hybrids (PHEVs) do have a charger port and can run on electric power alone for short distances, but standard hybrids cannot.

How long does an electric car battery last before I have to replace it?

Most EV batteries retain 85 to 95 percent of their capacity after 8 years of normal use. Manufacturers may provide at least 70 percent capacity for 8 years or 100,000 to 150,000 miles. Many batteries last 15 to 20 years or longer, but degradation accelerates in hot climates or with frequent fast charging. Replacement outside warranty can cost £4,000 to £15,000.

Is a hybrid cheaper to run than an electric car?

No. Electric cars cost roughly one-third as much per mile to run because electricity is cheaper than petrol. Hybrids use less petrol than traditional cars but still cost more per mile than electric cars. Over 100,000 miles, an electric car saves £3,000 to £8,000 in fuel compared to a hybrid.

What happens if I run out of battery in an electric car?

Modern electric cars warn you well before the battery is empty, similar to a petrol car's fuel gauge. If you ignore the warnings and the battery fully depletes, the car stops. You cannot coast to a charger or call for a tow easily. This is why range and charging access matter for electric car ownership. Plan trips around charger locations, and charge when the battery drops below 20 percent on long drives.

Do electric cars need oil changes?

No. Electric cars have no petrol engine, so they need no oil changes, spark plug service, or transmission fluid. Maintenance is limited to tyre rotation, cabin air filter replacement, and battery thermal management. This is one reason electric cars cost less to maintain over their lifetime.