v5.2 β— vehiclesopen formula · no fuel-type bias

How much car does it take to move one human?

The Transport Efficiency Index scores vehicles on the energy, mass, drag and power they spend per seat — not on what’s in the tank. A 2.5-tonne electric SUV can sip electricity and still waste most of what it is.

fig.1 — mass per person vs. TEI · full load
Each dot is one vehicle. Click to open it in the index. The trend is the whole argument: mass per seat predicts efficiency better than fuel type.
Best
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Median
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Worst
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01 / formula

One reference car.
Four ways to need more.

Every car is compared with one fixed reference: a sensible small car, per person. Each factor says how much more (or less) car it takes per occupant. The factors are multiplied, so units don’t matter, and the result sits on a log scale: the reference scores 85, and every doubling of “car per person” costs 30 points. No stretching, no dataset-relative scaling. Select a term.

TEI = 85 − 30 · log₂(E.40·M.35·D.10·P.15·B.15) // each factor = this car per occupant ÷ reference car per occupant // battery: only the part beyond 300 km of real range // occupants // constants fixed; never rescaled per dataset
fig.2 — distribution of TEI scores · full load
02 / index

The index.

Search like a terminal: free text, or queries such as type:electric seats>=4 hp<150. Click a row for the per-seat breakdown against the dataset median.

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loading… · ↓ csv
# Vehicle Energy kg hp seats kg/pers kWh/pers·100km TEI 5.2β
03 / why
Efficiency isn’t what a car burns. It’s how much car you move to move a person.
01 material

How much mass and road space the vehicle takes up for what it does.

02 occupancy

How many people it can realistically carry — every cost is divided by seats.

03 idle power

How much performance it hauls around that daily driving never uses.

04 not fuel-neutral

Small and simple wins, whether it’s a compact EV, a hybrid or a city petrol car.

Keyboard

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focus search
j k
move through rows
enter
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all seats / driver only
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clear / close