EV vs Plug-in Hybrid vs Petrol: The True Cost, CO₂ & Depreciation Battle

Compare EVs, PHEVs, and petrol cars for cost, CO₂ emissions, depreciation, and tax. See BMW 4 Series examples and why buying used could save you thousands.
Pathway: blog/ev-vs-hybrid-vs-petrol-costs-co2-depreciation

Introduction

The choice between a full electric vehicle (EV), a plug-in hybrid (PHEV), and a petrol car is no longer a simple matter of fuel economy. In 2025, it’s about:

Upfront price
Running costs (fuel, charging, servicing)
CO₂ emissions (in use and in production)
Depreciation
Company car tax

At anycolourcar.com, we help drivers in Barnsley and across South Yorkshire navigate these choices. This guide compares all three drivetrain types — and uses the BMW 4 Series as a real-world example — to see which is cheapest and which fits different driving patterns.

1. Purchase Price & Depreciation

Vehicle Type	New List Price (avg)	3-Year Used Price	Depreciation over 3 Years
Full EV	£30k – £40k	£18k – £28k	30–45%
PHEV	£30k – £40k	£17k – £27k	35–50%
Petrol	£20k – £30k	£12k – £20k	25–35%

Takeaway: EV and PHEV values drop faster in the early years as tech moves quickly. Buying used avoids the steepest depreciation hit.

2. Running Costs

Vehicle Type	Fuel/Electric Cost per Mile	Annual Servicing	Insurance
Full EV	3–5p (home), 12–15p (public)	Low – ~30% less than petrol	Slightly higher
PHEV	5–8p (charged daily) / up to 15p if not charged	Medium – more complex than petrol	Similar to petrol
Petrol	14–18p	Medium	Usually cheapest

3. CO₂ Emissions in Use

Vehicle Type	Tailpipe CO₂	Notes
Full EV	0g/km	UK grid electricity is ~40% renewable and improving.
PHEV	30–50g/km (official)	In real-world, can exceed 100g/km if rarely charged.
Petrol	120–180g/km	Higher in urban stop-start conditions.

4. CO₂ in Production

Vehicle Type	CO₂ in Manufacturing	Notes
Full EV	~8–12 tonnes	Battery production is energy-intensive; offset in 2–3 years’ use vs petrol.
PHEV	~7–10 tonnes	Dual drivetrain adds complexity.
Petrol	~5–7 tonnes	Lower initial footprint but far higher over lifetime.

5. Company Car Tax (BIK – 2025)

Vehicle Type	BIK Rate	Example £35k Car – Annual Tax (20% taxpayer)
Full EV	2%	~£140/year
PHEV (<50g CO₂, 40+ mile range)	5–8%	~£350–£560/year
Petrol	25–37%	~£1,750–£2,590/year

6. The Impact of Public Charging Costs

Public charging can change the equation dramatically:

Charging Method	Cost per kWh	Full Charge Cost (BMW i4 – 77kWh)	Range	Cost per Mile
Home (off-peak 8p)	£0.08	£6.16	~300 miles	2.1p
Home (standard 28p)	£0.28	£21.56	~300 miles	7.2p
Public Rapid (45p)	£0.45	£34.65	~300 miles	11.6p
Public Rapid (60p)	£0.60	£46.20	~300 miles	15.4p

If you mostly rapid-charge, EV running costs can approach those of a petrol car.

7. Real-World Case Study – BMW 4 Series

Models compared:

BMW 420i M Sport – Petrol
BMW 430e M Sport – PHEV
BMW i4 eDrive40 M Sport – EV

Category	BMW 420i (Petrol)	BMW 430e (PHEV)	BMW i4 (Home Charging)	BMW i4 (Public Charging)
List Price (new)	~£43,000	~£50,000	~£65,000	~£65,000
3-Year Used Price	~£30,000	~£32,000	~£42,000	~£42,000
Depreciation (3 yrs)	~30%	~36%	~35–40%	~35–40%
Fuel/Electric Cost per Mile	15–17p	5–8p / up to 15p if not charged	4–6p	12–15p
Annual Servicing	~£500	~£550	~£350	~£350
Tailpipe CO₂	~146g/km	~30g/km (official) / ~80–100g real	0g/km	0g/km
CO₂ in Production	~6t	~8t	~10–12t	~10–12t
Company Car Tax (20% taxpayer)	~£2,666	~£700	~£260	~£260
Range (Electric)	N/A	~25–35 miles + petrol backup	~300 miles	~300 miles

BMW 4 Series – What It Shows

Best for tax savings: BMW i4 (especially with home charging)
Best for mixed driving: BMW 430e – only if plugged in daily
Best for no charging access: BMW 420i petrol
Best overall value: Used i4 or 430e — avoids steep depreciation while keeping running costs low

Conclusion – Why Buying Used Makes Sense

When you combine CO₂ in production, depreciation, and real-world running costs, one clear truth emerges:

If you’re going EV or PHEV, buy used.
You avoid the steepest depreciation, cut the CO₂ cost of manufacturing a new car, and still benefit from low running costs — especially if you have home charging.

At anycolourcar.com, we can help you find a used BMW i4, 430e, or 420i (and many others) to fit your budget and driving needs, whether you’re commuting in Barnsley, touring South Yorkshire, or running a cost-efficient company car.