Everyday Myths

Modern cars generally do not need long warm-up idling before normal driving. Extended idling can simply burn fuel while the car goes nowhere.

Higher-octane gasoline is not an automatic performance upgrade for every engine. The right fuel is the grade your vehicle is designed to use.

A longer dishwasher cycle does not necessarily consume more energy. Eco modes can trade time for lower temperatures and reduced resource use.

Modern phones manage charging automatically, so overnight charging is more nuanced than the old claim that leaving a phone plugged in simply overcharges it.

An unused charger can draw standby power, but modern power supplies are subject to efficiency standards. The real question is how much the idle draw matters.

A lower unit price does not guarantee lower household spending. Bulk buying only saves when you actually use enough of what you buy.

A generic or store brand can cost less without automatically being inferior. Quality depends on the product, specification and manufacturer—not the logo alone.

Closing HVAC vents in unused rooms sounds like an easy way to save energy, but forced-air systems do not always work that way.

Does switching a light on use so much electricity that leaving it running is cheaper? For modern lighting, the answer is usually no.