Environmental Impact
This category is tricky because biofuels are very similar to hydrocarbons and have some of the same emissions problems that standard fossil fuels have. They can, however, be more environmentally friendly if care is taken in how they are produced and distributed. It is also the case that biofuels have an impact on the environment other than emissions, so we must consider several different subcategories under this heading.
Spills and Surface Contamination
Biofuels are not 100% safe but they are much safer than fossil fuels. If you were to spill a large quantity of biofuel into a concentrated area, it would likely kill living organisms and contaminate surround soil or water. However, the scale of the impact would be orders of magnitude smaller than with fossil fuels.
First off, biofuels are biological molecules and this means they are biodegradable. Bacteria and other organisms that live naturally in the soil and water are able to use biofuel molecules as energy sources and break them down into harmless byproducts. This means that even though concentrated biofuel spills can kill things like plants and smaller animals, they will not persist in the environment and cause damage or make an area uninhabitable for long periods of time.
Sulfur and Atmospheric Contamination
One of the major problems to arise from burning fossil fuels, especially coal, is acid rain that comes from the high sulfur content of these fuels. Biofuels can be produced in ways that completely eliminate sulfur and thus can eliminate this component of acid rain.
On the other hand, biofuels tend to contain high levels of nitrogen, which can form compounds that also lead to acid rain and atmospheric contamination. On the whole, the net impact on acid rain production is usually negative, meaning biofuels can reduce acid rain. Importantly, biofuels can be carefully produced to ensure that contamination is as low as possible, giving them an edge over fossil fuels because it is easier to avoid contamination in the production phase than it is to remove contaminants during refining.
Greenhouse Gas (GHG) Emissions and Global Warming
This is the area in which the most care must be taken in how biofuels are produced. If biofuels are produced in the “correct” way, they can greatly reduce greenhouse gas emissions. If produced incorrectly, they can increase emissions. Here is how.
First, plants use carbon dioxide, the major greenhouse gas of concern, to grow and produce food. So, plants are able to reduce the amount of carbon dioxide in the atmosphere and thus decrease global warming. Biofuels, when grown from plants, can thus offset their CO2 admissions because they take up the gas during growth that is produced when the fuel is burned. The idea is that if there is a one-to-one relationship, then the gas produced is the same as the gas taken in and there is no net impact on global warming. The problem is that achieving the one-to-one ratio may be impossible.
For starters, energy has to be invested into growing the crop itself. This energy comes in the form of planting seeds, tilling and preparing the ground, and importing water and nutrients. As it turns out, you cannot get something for nothing and so many crops require more energy input than they give out in the end. In other words, if you take into account the GHG emissions that occur just to grow the crop and add that to the greenhouse gas emissions from burning the crop, there is more CO2 produced than taken up and global warming worsens. As of yet, there is no good solution to this problem. Many companies are looking to invest energy in the form of sunlight so that there is no GHG emitted during the production phase. There is still a net energy INPUT, but no greenhouse gas is produced. This seems to be most feasible with algae.
The other problem to consider is land use. If land is cleared to grow a biofuel, then the plant life that existed there is eliminated. This problem is considered in more detail in the disadvantages of biofuel, but the main point is that carbon is produced to clear that land and the benefits of the plants on the land are lost. By some estimates and depending on the type of plant life removed, the impact could be a carbon debt that can take as long as 500 years to pay back. Again, the solution to this problem may be algae.
If the above technical impediments can be overcome, then the net impact of biofuels on the environment can be limited. In such a scenario, the greenhouse gas emissions and impact on global warming will be far lower with biofuels than with fossil fuels. The feasibility of achieving this advantage remains to be seen.
Energy Independence
This advantage is obvious and has no immediate drawbacks. If a country has the land resources to grow biofuel feedstock, then it can produce its own energy. This ends any dependence on fossil fuel resources, which are geographically limited to only a few places in the world. Given the amount of conflict that occurs over fuel supplies and prices, energy independence should have a net positive effect.
Despite this utopian ideal, the reality of biofuel energy independence is not so clear cut. First, not every country has the resources needed to grow biofuels. Many countries do not have the land area, access to water, or ability to produce fertilizer for crops and thus would still need to rely on others for their fuel to some degree.
As a second point, the shift in power could have a highly disruptive effect. First, national economies around the world depend on oil revenue to survive. Many Middle Eastern countries have a vested interest in ensuring that oil remains important and profitable given that as much as 90% of government revenue in these places comes from oil exports. To compound this problem, most of these countries would go from net energy exporters to net energy importers, further damaging their economies and forcing them to completely shift their industrial and commercial focuses.