
You've heard me say this before, and I'll say it again, because if you leave this course in a few weeks remembering only one thing (which I hope is a massive under-estimate), then it is this; When discussing possible solutions for pollution from fossil fuels, Efficiencies & Conservation are the 2 answers that are nearly always right. We have spent much time throughout this course talking about these two issues, so below are simple summaries of the main efficiency and conservation points as a reminder and refresher.
Automobile efficiency
This is not going to do much for SO2 emissions from gasoline engines (as the S content in gasoline is already so low, and getting lower (30 ppm)) but will lower emissions from diesel engines (low sulfur diesel achieves this too). However, increased efficiency in automobiles (mpg and passenger occupancy) will reduce NOx emissions. We talked about this in detail in the previous lesson on SMOG. Hybrid cars, electric cars, fuel cell cars and most alternative fuels will also reduce emissions either directly or through increased efficiency. There are also public transportation options.
Electricity Use
More efficient electrical devices in the home mean less electricity demand. Less electricity demand means less pollution.
Electricity Generation
There are plenty of non-fossil fuel utility options (renewable & nuclear). Biomass does not contain much S and so its utilization would help SO2 emissions. Natural gas combustion is a more efficient method of electricity production than existing coal utilities. While there are practically no S emissions there will be NOx emissions but at lower levels than old coal utilities (via a combination of increased efficiency and no fuel-NOx). If we use gasification we can clean the S and N from the gaseous fuel and obtain higher efficiencies in the generation of electricity (clean transportation fuels too).
Electricity Choice
You can, of course, pick from certain options how you want your electricity to be generated. Coal remains perhaps the cheapest, but if you are willing to pay the higher cost you can be green. In some cases, we are now seeing starting to see select renewable energy sources as the cheaper option.