How does the lighter in a BBQ grill work?

Key Takeaways

BBQ lighters generate a spark by applying pressure to certain crystalline materials like quartz, which creates a high voltage. This is called piezoelectricity.
This voltage, often thousands of volts, ignites the gas in the grill by producing a spark similar to that of a spark plug in gasoline engines.
Piezoelectric materials are also used in devices like digital watches for sound production and in various electronic components due to their ability to convert mechanical pressure into electrical energy and vice versa.

A BBQ lighter uses something called piezoelectricity to generate a nice spark that lights the grill. "Piezo," in Greek, means "pressure," and you find piezoelectric materials in a number of different places. For example, all of these products depend on the piezoelectric effect:

The push-button igniter in a gas BBQ grill or fireplace
Push-button cigarette lighters
Piezoelectric beepers (common in digital watches and anything electronic that goes "beep")
Piezoelectric tweeters in stereo speakers
Sound-generating arrays for sonar, fish finders and ultrasound devices
Crystal microphones
Phonograph needles
Quartz crystals used in most digital clocks and timers as the time base

Certain crystalline materials (like quartz, Rochelle salt and certain ceramics) have piezoelectric behavior. When you apply pressure to them, you get a charge separation within the crystal and a voltage across the crystal that is sometimes extremely high. For example, in a BBQ lighter, the popping noise you hear is a little spring-loaded hammer hitting a crystal and generating thousands of volts across the faces of the crystal. A voltage this high is identical to the voltage that drives a spark plug in a gasoline engine. The crystal's voltage can generate a nice spark that lights the gas in the grill.

In a crystal microphone, air pressure deforms the crystal enough to cause very small voltage changes in the crystal. These voltage changes are amplified and used to record or transmit sounds.

Piezoelectric materials also work the other way -- if you apply a voltage across the crystal, the crystal will change shape. The change is very slight in most cases, but it is enough to drive small speakers. For example, if you have a digital watch with a beeping alarm, the beeper is a little piezoelectric speaker.

Frequently Asked Questions

How long do piezoelectric igniters typically last in BBQ grills?

Piezoelectric igniters in BBQ grills generally last for about 10,000 to 20,000 clicks before the crystal or mechanism may need replacement.

Are piezoelectric igniters in BBQ grills affected by weather conditions?

Yes, extreme cold or moisture can sometimes impact the effectiveness of piezoelectric igniters, although they are largely robust and reliable in various weather conditions.