Vehicle Fuel · Tool Face-Off

Diesel Fuel vs Biodiesel

Quick answer

Diesel wins on infrastructure and cost today; biodiesel wins on conscience and carbon. Your wallet vs. the planet — classic showdown.

Our pick

Diesel Fuel

The old reliable: energy-dense, everywhere, and unapologetically fossil.

3.5★

Biodiesel

Fry oil's glow-up: cleaner burn, greener cred, same engine (mostly).

3.4★

Fuel Source

Crude oil (fossil)

Vegetable oils, animal fats, waste grease

Energy Content (BTU/gal)

~128,500 BTU

~118,000–122,000 BTU (B100)

Avg. Pump Price (US)

~$3.50–4.50/gal

~$3.80–5.50/gal (B100)

CO2 Lifecycle Reduction

Baseline (0%)

Up to 74% lower (B100)

Particulate Emissions

High

~47% lower (B100)

Cold Weather Gelling

Gels below ~-22°F (with additives)

Gels at 32°F or higher (B20 safer)

Engine Mod Required

None — runs stock

None for B20; seals/lines for B100

Availability

~150,000+ US stations

~700 US stations (B20/B100)

Blend Options

Straight diesel (B0)

B5, B20, B99, B100

Lubricity

Moderate (additives often needed)

Excellent — naturally lubricates injectors

Shelf Life

12–24 months

3–6 months (degrades faster)

Federal Tax Credit

None

Up to $1.00/gal blender's credit

Diesel Fuel

Emissions★½☆☆☆

Availability★★★★★

Cost Stability★★★☆☆

Energy Density★★★★★

Renewable Factor★☆☆☆☆

Engine Compatibility★★★★★

Cold Weather Performance★★★★☆

Biodiesel

Emissions★★★★☆

Availability★★½☆☆

Cost Stability★★★☆☆

Energy Density★★★★☆

Renewable Factor★★★★★

Engine Compatibility★★★½☆

Cold Weather Performance★★☆☆☆

Worth knowing

Biodiesel is the first fuel to meet EPA Clean Air Act standards as a fuel additive AND a fuel.
A B20 blend (20% biodiesel) reduces lifecycle CO2 by roughly 15% with zero engine changes.
Rudolf Diesel himself demonstrated his engine running on peanut oil at the 1900 World Exhibition.
The US produces over 1.5 billion gallons of biodiesel per year, mostly from soybean oil.
Diesel fuel energy density is ~10% higher than biodiesel, meaning slightly fewer MPG on bio.

Rudolf Diesel envisioned farmers running engines on their own vegetable oil — petroleum diesel essentially gate-crashed his invention and never left.

If you want

You want maximum range, zero hassle, and fuel stops everywhere

Petroleum diesel's infrastructure is unbeatable — fill up anywhere, any weather, no guesswork.

→ Pick Diesel Fuel

If you want

You want to cut emissions without buying a new vehicle

A B20 blend drops particulates and CO2 meaningfully with no engine modifications required.

→ Pick Biodiesel

If you want

You run a fleet and care about long-term fuel system health

Biodiesel's superior lubricity extends injector and pump life, saving on maintenance costs.

→ Pick Biodiesel

If you want

You live somewhere cold (below freezing winters)

Biodiesel gels at much higher temperatures — B100 in a Minnesota January is a bad time.

→ Pick Diesel Fuel

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