The methane sensor we will use is the MQ-4 sensor. This is a sensor that is sensitive to effects of methane.

1. MQ-4 Methane Sensor Circuit Built with an Arduino | ISweek - Industry sourcing
In this project, we will go over how to build a methane sensor circuit with an arduino.
The methane sensor we will use is the MQ-4 sensor. This is a sensor that is sensitive to
effects of methane.
Methane (CH4) is a colorless, odorless gas with a wide distribution in nature. Methane is
known chiefly as being the principal component of natural gas, which is a mixture
containing about 75% methane (CH4), 15% ethane (C2H6), and 5% other hydrocarbons,
suh as propane (C3H8) and butane (CH4H10).
The principal use of methane is as a fuel. The combustion of methane is highly
exothermic, meaning reactions create the release of a great deal of energy. The energy
released by the combustion of methane, in the form of natural gas, is used directly to
heat homes and commercial buildings. It is also used in the generation of electric power.
During the past decade, natural gas accounted for about 1/5 of the total energy
consumption worldwide and about 1/3 in the United States.
Much debate has been stirred on whether natural gas is more green, meaning better for
the environment, than coal. This is because methane, when burned, emits less carbon
dioxide than coal. Carbon dioxide, CO2, is a dangerous greenhouse gas. However, when
unburned, when it is vented or leaked directly into the atmosphere, methane is far more
potent than carbon dioxide. In terms of its contribution to global warming, it is 23 times
more powerful than carbon dioxide.
Thus, methane is a powerful gas that can do a lot of good and potentially a lot of bad at
the same time.
Therefore, it's a gas that's important to monitor.
And to do so, we need a methane sensor. So this is the device we will build in this
project. OUr device will be able to detect the gas methane and tell us its concentration in
the air.
Components Needed
• MQ-4 Methane Sensor
• Arduino
• LED
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