As the world increasingly shifts its focus towards sustainabl? and ?co-fri?ndly ?n?rgy solutions, th? d?mand for alt?rnativ? fu?ls such as biogas and compr?ss?d natural gas (CNG) has s??n a significant ris?. As the world increasingly shifts its focus towards sustainabl? and ?co-fri?ndly ?n?rgy solutions, th? d?mand for alt?rnativ? fu?ls such as biogas and compr?ss?d natural gas (CNG) has s??n a significant ris?. As the world increasingly shifts its focus towards sustainabl? and ?co-fri?ndly ?n?rgy solutions, th? d?mand for alt?rnativ? fu?ls such as biogas and compr?ss?d natural gas (CNG) has s??n a significant ris?.