FRIDAY, FEB 3, 2023: NOTE TO FILE

Module 4-14

Biofuels

Biofuels are produced from various crops and have their origin in agriculture or aquaculture. They are used as an alternative to fossil fuels for powering cars or machinery. As a result, the basic materials have fixed current carbon, which is then released when burned or used in a vehicle. Carbon is used as part of the biofuel production process for fertilizer, farm machinery, transportation and also for distillation in ethanol from sugar cane. As a result there are different ratios for biofuels of energy in and energy out. The type of biofuel and location of its production greatly impacts the environmental impact that it causes. For example palm oil plantations are one of the major causes of rainforest destruction.

The two most common current biofuels are bioethanol, which can be blended into petrol, and biodiesel, which can be blended into diesel. Blended in small quantities (currently up to 5%) these biofuels can be used safely in today's road vehicles. It is also possible to use higher blends of biofuel (100% biodiesel and 85% ethanol) but this may require modifications to engines.

Biofuels are not land efficient. In many cases biofuel replaces crops that were grown for food. There is an estimate that if the EU were to use 5% biofuel for powering its vehicles it would require a quarter of Europe's agricultural land. For the US to grow enough biofuel to power all of its cars it would take four times the country's arable land (more on the impact of inappropriate use or production of biofuels).

Rape seed: There are substantial crops of rape seed (canola) grown in Scotland and Northern Europe. With bright yellow flowers the fields are hard to miss when they are in bloom. Rapeseed can be used to produce biodiesel. The land efficiency is moderate and the advantage is that it can replace the use of fossil fuels.

Cellulosic ethanol has great promise. It comes from grass, trees or the non-edible parts of plants. It is five times better in terms of its net energy balance than corn-based ethanol. It can be produced with fast-growing grasses such as switchgrass that absorb carbon dioxide as they grow. Another advantage is that cellulosic ethanol plants will be able to run their energy-intensive boilers on the plant waste from their own processes (corn ethanol plants use natural gas). Emissions are 91% less than fossil fuels. The main current problem is production cost. Further research and development is taking place.

 

Sugarcane ethanol is quite efficient in the use of land. However the waste from the sugar cane plants is burned in the distillation process for cane ethanol. Current practice also leads to land degradation or the deforestation of the rainforest. This is particularly true of sugarcane in Brasil; the fires, the degradation of the land, the detraction of land that could be used for growing food and the miserable and toxic conditions for the workers outweigh many of the benefits.

Palm Oil biodiesel like sugarcane is often grown on land that was cleared of tropical forests. This causes an enormous release of greenhouse gas pollution which outweighs any benefit. The palm oil industry is causing environmental devastation, social breakdown, health problems, and massive habitat and species loss in Malaysia, Indonesia and Papua New Guinea and other parts of the world. The fires emit large amounts of CO2 into the atmosphere and destroy the incredible biodiversity that rainforests support. Orangutans which are some of the World's most endangered species are killed daily in palm oil plantations.

Corn ethanol is poor in land efficiency. It is the most wasteful of the biofuel crops. It only saves 22% of emissions compared with fossil fuel and energy balance is low at 1.3:1. The corn is also often produced using lots of fossil fuel rich fertilizers and most crops in the USA are genetically modified and therefore come with the associated risks.

Algae are tiny biological factories that use photosynthesis to transform carbon dioxide and sunlight into energy so efficiently that they can double their weight several times a day. Using algae to produce biofuel is still in the research stage but it shows excellent promise. Algae can grow in salt water, freshwater or even contaminated water, at sea or in ponds, and on land not suitable for food production. It can even be fed carbon dioxide to make it grow faster.

Recycled oil: Cars and trucks with diesel engines can run on frying oil that was used by restaurants like fish and chip shops. The car exhaust smells like chips. While there is far from being enough of this type of recycled oil for wide use, it can be a solution for some people who like to be super green and to save money at the same time.

 

4.9. Pause and Bring it to Life

Take some time to investigate where the energy you use everyday comes from: at home, work and school; for heating, cooking, general power, etc.

Some guiding questions:

1. If you live in the city or suburbs, where does your energy come from?
2. How regenerative and sustainable are those sources? How resilient?
3. Do you and other people in your community have access to alternative sources of energy?
4. If you live in a rural area, what are your sources of energy? Are they resilient and regenerative or sustainable?

 

Module 4, lesson 15

 

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