Methane monitoring and detection apparatus and methods

A gas detection system comprising:

• a gas monitoring device comprising:
• a focusing optics assembly configured to receive a transmitted light from a passive light source;
• a light distribution device configured to receive the transmitted light from the focusing optics assembly and further configured to randomize the transmitted light into a randomized transmitted light and is further configured to simultaneously distribute the randomized transmitted light into a plurality of output channels of substantially equal irradiation energy;
• a plurality of optical filters corresponding to the plurality of output channels wherein each of the plurality of filters is configured to receive the randomized transmitted light and to transmit a sensing light of a preselected wavelength range;
• a plurality of photodetectors corresponding to the plurality of optical filters and configured to receive the sensing light and further configured to output a current proportional to the total irradiance energy of the sensing light;
• and
• a processor electrically coupled to the plurality of photodetectors and configured to determine a relative attenuation of the sensing light for the plurality of output channels in the presence of a gas.