Biofuel for transport

In the industrialized countries, the transport sector is responsible for about one quarter of all energy consumption, so a low carbon solution is imperative.

Biofuel has been promoted as being green, but lately it received more opposition from green NGOs than any other transport fuel.

Is biofuel the long-awaited sustainable solution for the transport sector? Or are the drawbacks bigger than the advantages and should we put our efforts in other solutions?

Leonardo Energy addressed this subject on a Discussion Webinar on 26 January 2008. The following are a few of the major points arising from that discussion.

1) A few key figures

Biofuels are being produced in ever larger volumes. A maize-based ethanol boom in the USA has led to the production of 16 million cubic metres annually. Brazil has a longer tradition and produces 15 million cubic metres of ethanol using sugar cane. Production costs for bioethanol have come down to 0.15 – 0.18 euro per litre. One litre of ethanol is the equivalent of 0.671 litre of gasoline in terms of energy content.

2) How carbon neutral are biofuels?

Biofuels are definitely not energy or carbon neutral. Growing and harvesting the crops requires energy, as well as refining and transportation of the end product to the place of use. The exact carbon emission values differ greatly depending upon the particular type of biofuel. The same biofuels can even have significantly different values, depending upon which production method is used. A Life Cycle Assessment (LCA) is required to map the complex processing and handling of biofuels and to create an accurate reference by which they can be compared.

3) The social dimension

GreenHouse Gas (GHG) emissions during the processing and handling of biofuel must also be put in balance with the social consequences. This often makes the debate even more complex and contentious. A good example is the ethanol production from sugar cane in Brazil. Sugar cane fields are first flash burned to make the manual harvest easier, producing high levels of air pollution and ash in the process. The manual harvest could be replaced by machines, eliminating the necessity of burning the fields. But mechanized harvest also produces GHG emissions. Moreover, it takes away jobs from the very poor and is often coupled with the use of herbicides and fertilizers which have their own negative impact on the environment.

4) Food or fuel?

Another politically charged question is whether the production of biofuel puts food production under pressure. This dilemma is sometimes phrased simplistically 'Should poor people starve because rich people want to travel?' or 'Should we put eatable products into our cars?' Indeed, importing large quantities of food crops like maize from developing countries into Europe is not really a sustainable practice from a social point of view.

One could follow the reasoning that in equatorial countries, where the sun shines abundantly year around, energy could be produced by photovoltaic panels while in the temperate zones, where sunshine is less abundant but often accompanied by crop surpluses, energy could be derived from biomass. On the other hand, in some regions of developing countries, biofuel production could add value to the land use for poor farmers and attract capital to improve productivity in food production.

5) Forest or fuel?

A rule could be put into effect to only grow biofuel feedstock in soil that is not used for food crops. But this poses yet another danger, namely that forests would be cleared, either to harvest the wood directly as biofuel or to provide agricultural land to grow biofuel feedstock, or both. Tropical forests are far more valuable as a carbon sink and as a source of biodiversity.

6) Certification for biofuels

Certification of biofuels would be a possible route to ensure that they are produced in a socially and environmentally sound manner. Devising such a classification though is not an easy matter. Researchers in Norway are currently drafting a report on biofuel certification that will soon be available.

7) The second generation

Most of the arguments against biofuels are related to the so-called 'first generation' of biofuels which come from feedstock such as wheat, maize, sugar beet, and sugar cane. The 'second generation' biofuels are less carbon intensive and not as competitive with food production. Examples are cellulosic ethanol from fast-growing crops and biofuel from algae.

8) Biofuels in the EU

The EU has set a target of having 10 per cent of the overall fuel supply for transport in the form of biofuels in Europe by 2020. This position has been severely criticized because it does not sufficiently take into account the questions regarding carbon intensity and competition with food crops.

However, some proponents argue that even if the second generation of biofuels is not yet market ripe, setting ambitious targets today could enable the building of a market that paves the way for better technologies. We must then ask the question whether building the wrong markets could pave the way to significant progress.

Another important consideration is whether biofuels are actually making Europe more oil independent. In Brazil and the U.S., having vast areas of agricultural land, this is certainly the case. In Europe however, one can seriously question this. Setting high targets for biofuel consumption in Europe pushes the import of crops. In Rotterdam, they want to set up the first biomass hub in the world. Some find it questionable whether it can be a sustainable practice to import such large volumes of biofuels from abroad.

9) Alternative sustainable technologies

Biofuels are not the only game in town for developing sustainable transport systems. With battery technology developing fast, mass market electric vehicles are likely to appear in the next decade. And despite limited progress in recent years, research on fuel cell car motors running on hydrogen continues.

10) Which should be chosen first, the energy source or the energy carrier?

A side-note in this debate is the difference between the energy source and the energy carrier. The sustainable energy carriers — electricity, hydrogen, ethanol, or biodiesel — are each related to a specific type of engine (electric motor, fuel cell, gasoline engine, or diesel engine). All four of them can be produced from various kinds of energy sources, some of which are more sustainable than others.

On which element should we concentrate first; the energy sources or the energy carriers? The choice for the energy carrier should be made for the future, since it is related to the development of the car engine and a distribution network. Switching from one energy carrier to another is difficult and costly. Once the energy carrier is chosen, the energy sources to produce it could easily evolve over time. So should we first choose the energy carrier? For instance, first create a market for ethanol and then develop sustainable ways to produce ethanol?

Maybe, but in order to make the best choice of the energy carrier, one should know which has the largest potential to be produced by sustainable energy sources, today and in the future. This is hard to predict. So the question remains; should we develop the energy sources first or last?

Comments

lindsay leveen's picture

Mother nature did not intend photosynthesis to propel the 700 million vehicles on planet earth. Your car has the appetite of twenty full grown humans. Yes the energy content of the gasoline used in a car each day is like a 40,000 kilocalorie diet. Nature intended photosynthesis for food. Vehicles were not part of the masterplan. Luckily for us photosynthesis is only 0.1% efficient so we do have some tricks up our sleeves in the form of solar energy (thermal or photovoltaic).

Ger's picture

If you use numbers, use those numbers correctly:

photo-efficiency : ranging from 2% to 12% for producing the starch in the plants. It's up to you how much you can get out of it. Let's say 10%. Then you have the right figure of about 0.2%. Energy crops can do a lot better (of extracting the fuel) even up to 50%, resulting in an efficiency of 1% to 6%.

A car using 40,000 kcal or 46.6 kWh can transport a load of 1000 kg over a distance of a 100 km. I don't see humans do that just as efficiently as a small truck.

Do not forget that solar panels do cost an awfully lot of energy to produce. That would not be important if those lasted forever. But they do not.

If we (all of us) take into account the effort for producing a fuel from a renewable resource than we should do anything which has a favorable energy balance in comparison with the fossil fuel. When we can get rid of the fossil fuel by replacing with bio sources and saving programs for about 40%, then it is time to optimize and improve.

Rejecting solutions based on "not so good as thought, let's wait for a better one" is a sure recipe.

By Ger (not verified) 09/03/2008
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