6 June 2011 | Andrew Purcell
Biofuel

 

Silver bullet or panacea? The debate on biofuels is a heated one. However, this polarised debate has often been overly simplistic and ignores recent developments in biofuel technologies. As such, blanket statements about biofuels can often be misleading. Consequently, a more realistic approach is required, with biofuel technologies being judged on an individual, case by case basis.

The UK Department of Energy and Climate Change (DECC) states that a quarter of UK CO₂ emissions in 2010 came from transport – mostly powered by fossil fuels. This highlights why a greener way to travel is needed.

BP’s head of strategy, regulatory affairs and communications, Olivier Mace, has suggested that biofuels are the only alternative to oil if we are to decarbonise transport (11 March 2011). This view echoes that of many other industry leaders, but it is not accepted by all. For all their merits, biofuels have faults and as a business owner or executive the conflicting information and opinions on biofuels can be bewildering. Climate Action has compiled this guide as a no-nonsense overview of the biofuels sector and the policy surrounding it. We outline the different types of fuels and their respective pros and cons, so you can decide whether they are a climate hit or just hype.

 

What are biofuels and why do we need them?

Biofuels are renewable liquid or gaseous transport fuels derived from biomass (bacterial, plant or animal material). Crucially, they are renewable and form quickly, unlike fossil fuels, which also come from biological material, but take millions of years to form. Despite seeming like a modern invention, biofuels have actually been around since the early twentieth century – Rudolph Diesel (inventor of the diesel engine) ran an engine on peanut oil at the Paris World’s Fair in 1900.

Part of the confusion and controversy surrounding biofuels lies in the fact that they can come from a variety of different sources – these are grouped into generations. Each generation has its own respective pros and cons. Often incorrectly, the criticisms of older generation biofuels are transferred onto newer ones.

When the Nuffield Council on Bioethics examined the ethical issues surrounding biofuels in 2011, they said that biofuel development is driven by three challenges: energy security, economic development and climate change.

Energy security

With rising oil prices and a market that is sensitive to events, such as recent political instability in the Middle East, energy security is once again back on the political agenda. Oil, is currently at well over US$100 a barrel. This has led to increasing speculation that biofuels could be set to make a return. The EU is already set to produce 9% of its road transport fuel from biomass by 2020. But if oil prices remain at this high level for an extended period, the production of biofuels may soon become economically viable, even without current government subsidies and mandates.  Fossil fuels, particularly oil, have driven the world’s economies in the past, but with supplies falling, biofuels could increase future energy security. If countries, or even local communities, could grow their own fuel crops, rather than needing to purchase or import fossil fuels, they could become energy independent. This is a great chance for developing countries to become less dependent on the expensive, and often volatile, oil market.


Economic development

Investment in the biofuels sector could boost global economic development, particularly in developing countries where farmers, who make up a large proportion of the population, would have a new source of income. Also as the economies of developing countries grow, so too will demand for energy and biofuels may have a role in meeting this.


Climate change

Biofuels are a renewable energy source but, like fossil fuels, they still require burning and therefore still emit greenhouse gases. However, unlike fossil fuels, they do not contain high levels of toxins and they should, if produced appropriately, give off fewer emissions. While growing, biofuel crops have the potential to mitigate climate change, by locking up CO2 through the process of photosynthesis.

In theory, biofuels allow society to continue developing at the same rate, providing transport fuel that could replace oil without any significant infrastructure or mechanical changes to how people live. Biofuels could be a quick fix to help the world’s transition to longer-term, more expensive and complex - but even greener - power sources. Biofuels could, at least in principal, be ‘carbon neutral’, since the plants remove a similar amount of carbon from the atmosphere when they grow as to that which they release when they are burnt as a fuel.

Unfortunately, despite these apparent advantages, biofuels are far more complex and can be environmentally damaging, as well as having negative social impacts. Biofuels are generally crops and, like any crop, they require resources, such as water and fertilisers, in order to grow successfully. Consequently, many of the environmental concerns associated with industrial scale, monoculture farming also arise with producing biofuels.
 

 

Policies and legislation

EC Renewable Energy Directive (2009)
UK Renewable Transport Fuel Obligation (Amendment) Order (2009)

 

Types of Biofuel

1st Generation - traditional crops: soybean, palm oil, corn, etc.

These are the established fuels, using widespread technologies from crops such as corn, soybean and oil palm. The fuel is made from the crop into sugar, starch or vegetable oil. Sugars and starch are fermented to make an alcohol fuel that can be blended with petroleum or sometimes used pure. The fat in vegetable oils can be converted into biodiesel, which can power a car on its own or in combination with standard diesel.

Corn is a common source of bioethanol, particularly in the US where there have been concerns over energy security. Another common source of bioethanol is sugar cane; this is particularly popular in Brazil which is now the world’s biggest bioethanol fuel exporter.

Although controversial, palm oil is another established source of biodiesel. Malaysia and Indonesia are the world’s biggest palm oil producers – some of which goes into food production, but a large portion is for the biofuels industry.

Pros

• The processes to convert the crops into biofuels are relatively simple, because the technology exists and is well established.
• First generation biofuels can take of advantage of agricultural overproduction – excess food crops can be sold to biofuels manufacturers, therefore reducing waste.

 

Cons

• Some economists argue that biofuels contributed to driving up world food prices to the record highs seen is 2008. However, other economists dispute these claims in what has become known as the ‘food versus fuel’ debate.
• Biofuel plantations may compete with traditional food crops for space.
• The need for space for biofuel crop plantations can be a driver of deforestation. This has particularly been an issue in south-east Asia.
• Monoculture biofuel crop plantations lead to decreased biodiversity.
• Growing first generation biofuels on a wide scale is likely to significantly increase the rate at which fertiliser and fresh water supplies are exhausted.

2nd Generation - high energy crops: miscanthus, short rotation coppice poplar, willow, etc.

Second generation biofuels are derived from non-food crops. These include waste biomass, the stalks of wheat, corn, wood, and special-energy-or-biomass crops, such as miscanthus. Woody, herbaceous crops like miscanthus have low maintenance costs and can easily be combusted to produce relatively large amounts of energy. There are currently a wide range of second generation biofuels under development, including: biohydrogen, biomethanol, DMF, BioDME, Fischer-Tropsch diesel, biohydrogen diesel, mixed alcohols and wood diesel.

Pros

• Have a high energy yield
• Generally require less water and less fertiliser than first generation biofuels
• Perhaps most importantly, as second generation biofuels are derived from non-food crops, it is argued they do not push up world food prices like first generation biofuels may do.

Cons

• While second generation biofuels reduce the potential negative impacts of many first generation biofuels, such as water use, fertiliser use and increased competition for land area, they do not solve these problems entirely.
• As with first generation biofuels, second generation crops may lead to decreases in biodiversity, particularly if species-rich land is clear to make way for plantations.

 

3rd Generation - algae and bacteria

Third generation biofuel is not synthesised from plants, but from algae or bacteria. Early research has suggested that that algae can produce up to 30 times more energy per acre than land crops such as soybeans. However, these results are yet to be repeated on a commercial scale. The United States Department of Energy estimates that if algal fuel were to replace all the petroleum fuel in the United States, it would require only 15,000 square miles. This is less than one seventh of the land area currently devoted to corn production in the US.

Pros

• Require very little water, fertiliser and land area compared to earlier generation biofuels.
• Third generation biofuels do not impact negatively upon biodiversity.

 

Cons

• Although third generation biofuels have huge potential in the long term, they are currently still in the early stages of development. 

 

4th Generation - the future

Fourth generation biofuels are highly experimental and have not yet been clearly defined. Some fourth generation technologies are: decomposition of biofuels at high temperatures; artificial photosynthesis reactions, known as ‘solar-to-fuel’; and even genetically modifying organisms to secrete hydrocarbons.


Pros

•  Potential high energy yields with low input costs.

 

Cons

• Still in very speculative, early stages of development
• There is likely to be significant public opposition to the genetic manipulation of organisms to produce hydrocarbons.

Others

There are some biofuel technologies which do not fit easily into this four generation classification, such as biomass energy. Essentially, biomass energy is the burning of wood. However, it has limited use on larger scales.



Biofuels are not a silver bullet for the problem of increasing global energy needs in the face of dwindling fossil fuels and climate change. Nevertheless, if used correctly they are a useful energy source in what should be part of a broader portfolio approach.

However, if exploited at the expense of the environment, food supplies and human rights they can be extremely dangerous.

Biofuels could also be used to supply the non-fuel services that oil currently provides, such as plastics, synthetic fibres, etc. Arguably, over the long term, it is these potential uses which are more important than their use as transport fuel.

 

Image credits:

1. Flickr | Jurveston
2. Flickr | Matt Lavin
3. Flickr | Cathy, Sam, Max and Mai
4. Flickr | US Geological Survey
5. Flickr | Rosa y Dani

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