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Case study · BYD Sealion 6 · Cavite, PH · Dec 2025 – Jul 2026

PHEV running cost — eight months of tracked driving

Owned since September 2024; consistent refuel-by-refuel tracking started in December 2025. This covers the 9,600 km logged so far (Dec 2025 – Jul 2026) — a slice of the ~32,000 km lifetime odometer — with odometer- and meter-tracked efficiency, electric-vs-fuel running cost, usage split, and battery health for a BYD Sealion 6.

  • BYD Sealion 6
  • Plug-in hybrid
  • 9,600 km tracked
  • 65% EV usage
  • Cavite, Philippines

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The short version: 65% of the driving was electric, the combined figure landed at 5.79 L/100km, and electric kilometers cost less than half what fuel kilometers do (₱2.62 vs ₱5.92/km). The headline efficiency means little on its own — the real variable is the EV/HEV split, which is a function of charging access and discipline, not the car. Your numbers will move with where you can plug in, not your right foot. Read any single tank's efficiency with care, too: the car meters mains charging but not regen or engine-generated charge, so one interval's figure depends heavily on where it started in the charge cycle. The home charging behind this is solar-fed; that side is written up separately: Residential solar performance.

Headline numbers

Combined efficiency
5.79 L/100km

beats the 8–10 L/100km class benchmark

EV running cost
₱2.62/km

vs ₱5.92/km on fuel — 56% cheaper

Saved vs ICE
₱16,600

tracked window only · ≈760 kg CO₂ avoided

Battery health
99% SOH

after ~59 metered charge cycles

What the data shows

The split between electric and fuel driving climbed steadily from ~48% EV to a peak of ~76% by June 2026, and has been trip-driven since: 74%, then 38% on a road-trip tank, then 67% in July. EV kilometers cost ₱2.62 each against ₱5.92 on fuel, so every kilometer shifted onto electric saves about ₱3.30 at the current tariff — a wider gap than six months ago, because pump prices have climbed to ₱82.30/L from ₱53.04/L across the tracked period. That price rise, not the car, is what has moved running cost from ₱3.24/km in March to ₱4.76/km in July.

The ₱16,600 saved vs ICE above only covers the 9,600 km actually logged — it excludes the ~22,421 km driven between acquisition (Sep 2024) and when tracking started (Dec 2025), which has no recorded fuel/EV split. Extrapolating the tracked period's average cost/km across the full 32,021 km lifetime odometer puts estimated lifetime savings at roughly ₱55,300 — a rough estimate that assumes the untracked driving had a similar EV/fuel mix and pricing, not a measured figure.

Combined consumption of 5.79 L/100km comfortably beats the 8–10 L/100km benchmark for mid-size SUV PHEVs and undercuts a comparable ICE SUV by roughly 33–48% on running cost. Fuel efficiency held in a tight 8.1–9.5 L/100km band for seven intervals, then read 11.57 L/100km on a tank covering a provincial round trip. Trip telemetry from those same days puts the charge-sustaining driving at about 14.8 km/L on both legs, well ahead of the 11.0 km/L cumulative figure — so the tank reads thirsty because of how the car apportions distance between its two modes, not because the driving was wasteful.

Battery state of health is 99% after ~59 metered charge cycles (real cycling is higher — engine-generated charge is not metered), and the next scheduled service lands around 40,000 km or ~September 2026 — whichever comes first, roughly two months out at the current pace. See recommendations →

Cumulative cost & efficiency

ModeDistanceFuel / energyEfficiencyCost/km
HEV (fuel)3,360 km305.44 L9.09 L/100km₱5.92
EV (electric)6,240 km1,087.50 kWh5.74 km/kWh₱2.62
Combined9,600 km5.79 L/100km*₱3.77

*Combined efficiency converts EV cost into equivalent fuel liters. Total spend so far is ₱36,222 over 9,600 km.

Full analysis · trends · anomalies · projections →

Disclaimer: the report is AI-assisted. Efficiency, cost, and usage figures are derived from odometer and meter readings entered by hand, so accuracy depends on those inputs. Values are for personal tracking and should not be used for warranty claims, tax filings, or official reporting without independent verification.

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