Our Environment: Part 21 Biofuels

This option for providing power has not been discussed as much recently as it was a decade ago.  At that time many were looking at using corn waste, used cooking oil, and animal manure as a source of energy.  Some universities devoted a lot of their research dollars towards the topic.  But not as much today.

You might remember that our first source of energy for heating and cooking was wood.  A decade ago, some communities were considering returning to this source.  However, the problems that existed hundreds of years ago still exist today – mainly, is there enough wood.  It is a renewable resource, but it does not grow as fast as we use it.

One of the biofuels that did get a lot of attention a decade ago, and is still popular in some countries, is ethanol and biodiesel.  This has really caught on in Brazil and, to some extent, in the United States.  There are several advantages to this form of energy.  (1) Countries can supply their own source of fuel and are not dependent on importing from nations who have fossil fuels.  (2) If managed correctly – not removing plants faster than they can replenish themselves – there would be no increase in carbon dioxide emissions.  (3) They are available now, are easy to store and transport, can be distributed through existing fuel networks, and used in existing vehicles.

However, there are some problems…

Converting farmland to biofuel farms would decrease food production and overall biodiversity.  Here are some advantages and disadvantages of solid biomass.

Advantages	Disadvantages
Large potential supply in some areas	Nonrenewable if harvested unsustainably
Moderate costs	Moderate to high environmental impact
No net CO2 increase if harvested, and replanted sustainably	Soil erosion, water pollution, and loss of wildlife habitat
Can make use of agricultural, timber, and urban waste	Farms could compete with food crops

Biodiesel

Advantages	Disadvantages
Reduce CO2 emissions	Increased NO2 emissions and smog
Reduced CO emissions	Higher cost than regular diesel
High net energy for oil palm crops	Low net energy for soybean crops
Better gas mileage	May compete with food crops and raise food prices
Potentially renewable	Can make engines hard to start in cold weather

Ethanol

Advantages	Disadvantages
High octane	Lower driving range
Some reduction in CO2 emissions	Lower net energy
Potentially renewable	Higher cost
	Competing with food crops
	Higher NO2 emissions and more smog
	Corrosive
	Can make engines hard to start in cold weather

The potential of using biofuels is still here.  There are definitely some pros and cons to this form of energy for us to think about.  In our next article we will look at another that has been discussed a lot – geothermal.

References

Miller, G.T., Spoolman, S.E. 2011. Living in the Environment. Brooks/Cole Cengage Learning. Belmont CA. pp. 674.