Carbon Dioxide
In an ideal World, we probably wouldn’t burn fossil fuels, but if we continue to
do so the best possible outcome would be to get only emissions of water, carbon
dioxide and nitrogen. All of these are non-toxic and occur naturally in vast quantities,
although unfortunately the first two are known to be ‘greenhouse gases’ and are
therefore implicated in climate change. Carbon dioxide is considered to be more
of a threat than water vapour because it spends longer in the atmosphere before
moving to the next stage of its cycle.
The only effective way to reduce emissions of carbon dioxide is to burn less fossil
fuels which necessitates improving efficiency and / or replacing the fossil fuel
with a renewable alternative. The best alternative fuel from a climate change perspective
is probably methane, which is released as organic matter (such as food or animal
waste) is broken down by bacteria. Methane is itself a powerful greenhouse gas,
so there is a double advantage to be gained from burning it in place of fossil fuels.