שאלה | Is the following sentence true or false, and why? As long as there is some level of methane (CH4) in the biogas, regardless of concentration, it can be used as an energy source.

Is the following sentence true or false, and why? As long as there is some level of methane (CH4) in the biogas, regardless of concentration, it can be used as an energy source.

		True; CH4 is an extremely combustible gas, and even small quantities can be used for energy.
		True; since the CH4 is always separated from the “biogas mix” before it is used, its concentration is not important.
		False; biogas is only considered usable for energy purposes if the CH4 concentration is greater than 50-55%.
		False; unless there is sufficient H2 in the biogas, it cannot be utilized for energy