They wouldn't have advertised it as "CH4", that's not how people know it. It'd be methane or natural gas, more likely natural gas. Though the examples I'm comin

They wouldn't have advertised it as "CH4", that's not how people know it. It'd be methane or natural gas, more likely natural gas. Though the examples I'm coming up with are more recent than I was thinking (last decade) so unless GP is very young wouldn't have been around in their childhood. Continuing my search, but I have recollections of a 2000s push for natural gas that was heavily predicated on its "cleanness". Lots of city and school buses, for instance, were switching to CNG from diesel in that time period (and in comparison, CNG is almost certainly cleaner than diesel). EDIT: Ok, found some things. Google Image search for (no quotes) "clean natural gas" and set the range to 2000-2010. You'll find a variety of images both for and against this claim. Including things like "This Bus Is Running On Clean Natural Gas" (2009) [0] or "Clean. Affordable. Abundant. American. Natural gas is the answer. Tell Congress to put it to work." (apparently from 2010) [1] [0] https://images.app.goo.gl/yfrQn8fYrB7zLqqh9 https://images.app.goo.gl/yfrQn8fYrB7zLqqh9 [1] https://images.app.goo.gl/4Aj7ybMt3wVWq49BA https://images.app.goo.gl/4Aj7ybMt3wVWq49BA Here's [2] an example from the 1980s calling it cleaner, source for me was [3]. [2] https://drive.google.com/file/d/1ympy04dETxXWfqkCn0zm9NmE1z19x4PI/view https://drive.google.com/file/d/1ympy04dETxXWfqkCn0zm9NmE1z1... [3] https://www.theguardian.com/environment/2021/nov/18/the-forgotten-oil-ads-that-told-us-climate-change-was-nothing https://www.theguardian.com/environment/2021/nov/18/the-forg...