Reading fuel-saving claims
Explainers on the questions that decide whether a fuel-saving claim is worth anything — written because we could not find honest answers elsewhere, and in one case because we got it wrong ourselves first.
Why “20% better” is not “20% less fuel”
+20% → −16.7%Efficiency and consumption are reciprocals. A 20% gain in km/L is a 16.7% cut in fuel; a 43% gain is 30%. The conversion, where the confusion does real damage, and the mistake that sat in our own analysis for weeks.
Read the explainer →Where fuel-saving products actually intervene
Fuel · oil · airEvery product sold to a fleet acts at one of three points. The point of intervention decides what it can plausibly do — and what evidence should exist for it. Mechanisms compared, not percentages.
Read the explainer →Two pieces, because we would rather publish two that are worth reading than ten that restate the evidence pages. The regulatory landscape is covered on regulatory context, and how a trial should be run on measurement methodology — neither is repeated here.
What would you want explained?
If you are evaluating this product category and there is a question the evidence pages do not answer, tell us. That is how both of these came about.