Is RNG clean?

For the most part, yes, but the ultimate answer depends on the feed source. RNG can be co-mingled with geologic natural gas, and even though natural gas is the cleanest of the fossil fuels, all hydrocarbons contributed to global warming to some extent. However, RNG produced from dairy and swine farms have a negative carbon intensity factor, and therefore help eliminate methane from being released to the atmosphere. Methane can be up to 80x more detrimental to the environment than carbon emissions.