Choosing a car in New Zealand involves navigating a world of fuel efficiency, environmental impact, and of course, budget. Deciding between a petrol car and a hybrid can be a close call, so let's delve deeper into the cost breakdown to help you make an informed decision.

How much you save on fuel ? 

Here's an estimate of how much you could save annually by choosing a 1.8L petrol hybrid car over a regular 1.8L petrol car, assuming you drive 22km daily in New Zealand:

You could potentially save around NZ$1,074.00 annually on fuel costs by choosing a 1.8L petrol hybrid car over a regular 1.8L petrol car. But, this excludes the cost of maintenance, drop in fuel efficiency and car value due to battery degradation where you may lose owning a Hybrid car in the long run, if your usage does not exceed 8000kms./year

Fuel Efficiency FTW (For The Win):

This is the hybrid's shining star. With a 1.8L engine for example, a hybrid could achieve 20 kilometers per liter (km/L) compared to a petrol car's 10 km/L. If you drive 22 kilometers daily, that translates to a potential annual saving of NZ$1,074 (based on an average petrol price of NZ$2.67 per liter). Over several years, these fuel savings can be significant.

Maintenance Matters:

Hybrids do have a slight maintenance disadvantage. The electric motor and battery add complexity, potentially leading to NZ$100 more in annual maintenance costs compared to a petrol car.

The Depreciation Dilemma:

Hybrids generally hold their value better than petrol cars due to lower emissions. But battery degradation, the gradual loss of battery efficiency over time, can play a role. While some degradation is expected, it might make a hybrid slightly less desirable in the used car market compared to a petrol car with a simpler engine.

Battery Blues (or are they?):

Though not a common occurrence, a full battery replacement on a hybrid can be expensive. However, most hybrid batteries are designed to last the lifespan of the car, and warranties often cover them for several years.

The Bottom Line: It Depends

The best choice boils down to your driving habits and priorities. Here's a quick breakdown:

• High mileage driver who keeps cars for a shorter period? A hybrid might be a good fit due to the potential fuel savings outweighing the maintenance and depreciation considerations.

• Lower mileage driver or someone planning to keep the car for a long time? The cost benefits of a hybrid might be less clear-cut. The lower fuel savings might be offset by potentially higher depreciation due to battery concerns.

Calculations:

Assumptions:

Daily distance: 22 kilometers

Annual driving days: 365 (excluding non-driving days)

Fuel economy:

Petrol car: 10 kilometers per liter (reference value, can vary)

Hybrid car: 20 kilometers per liter (reference value, can vary)

Petrol cost: NZ$2.67 per liter (average for Unleaded 91 as of July 19, 2024)

Annual distance: Daily distance x Annual driving days = 22 km/day * 365 days/year = 8,030 km/year

• Annual fuel consumption for petrol car: Annual distance / Petrol car mileage = 8,030 km / 10 km/liter = 803 liters/year

• Annual fuel cost for petrol car: Annual fuel consumption * Petrol cost per liter = 803 liters/year * NZ$2.67/liter = NZ$2,144.01/year

• Annual fuel consumption for hybrid car: Annual distance / Hybrid car mileage = 8,030 km / 20 km/liter = 401.5 liters/year

• Annual fuel cost for hybrid car: Annual fuel consumption * Petrol cost per liter = 401.5 liters/year * NZ$2.67/liter = NZ$1,070.01/year

• Annual saving by choosing hybrid car: Annual cost for petrol car - Annual cost for hybrid car = NZ$2,144.01/year - NZ$1,070.01/year = NZ$1,074.00/year (approximately)

• Annual maintenance difference: NZ$100 (hybrid) - NZ$200 (petrol) = -NZ$100 (saving with hybrid)

• Yearly fuel cost increase due to battery degradation (example after 5 years): Let's say you drive 8,030 km/year (from previous example) and fuel cost remains NZ$2.67/liter. With a slight efficiency decrease, you might use: 8,030 km / 18 km/liter = 446 liters. This would be a cost of 446 liters * NZ$2.67/liter = NZ$1,189.42. Assuming the initial hybrid fuel cost was NZ$1,070.01 (from previous example), the increased cost due to degradation would be NZ$1,189.42 - NZ$1,070.01 = NZ$119.41 per year (increased cost).

So there you have it! Now you're officially smarter than most car sales men. Use this knowledge wisely, or at least to win your next argument over a false sale pitch the car sales guys make at the yard !

Author: Aqyaan Alam
(Prof. Data Analyst, Christchurch, NZ)