Photo: Will growing our fuels drive us to a cleaner future?

(Credit: Sweeter Alternative via Flickr)

By David Suzuki with contributions from David Suzuki Foundation Senior Editor Ian Hanington.

The shift from fossil fuels to renewable energy is occurring mainly at the power plant level. But what about transportation? Can we significantly reduce greenhouse gas emissions by switching to cleaner fuels? Or is this just an attempt to keep 20th century technology chugging along while trading one set of environmental problems for another?

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Biofuels aren't new and they aren't used solely for transportation. Power plants can burn wood, for example, and many of the first autos, including Ford's Model T, ran on ethanol or peanut oil. But they're now seen as an alternative to fossil fuels for transportation.

Biofuels offer several advantages over fossil fuels. Most are less toxic. Crops used to produce them can be grown quickly, so unlike coal, oil and gas that take millions of years to form, they're considered renewable. They can also be grown almost anywhere, reducing the need for infrastructure like pipelines and oil tankers and, in many areas, conflicts around scarcity and political upheaval.

The main biofuels are ethanol and biodiesel. Biomass like wood can also be burned directly for fuel, although that usually produces more greenhouse gas emissions to produce the same amount of energy as burning fossil fuels. Biofuel greenhouse gas emissions are offset to a great extent because plants absorb and store carbon dioxide while they're growing and sometimes in roots left in the ground, so CO2 emissions are roughly equal to or less than what the crops store.

Despite the advantages, numerous problems have led many to question whether biofuels are a green alternative. Andrew Steer and Craig Hanson of the World Resources Institute noted in the Guardian biofuel has three major strikes against it: "It uses land needed for food production and carbon storage, it requires large areas to generate just a small amount of fuel, and it won't typically cut greenhouse gas emissions."

Producing biofuel with crops like corn often requires converting land from food to fuel production or destroying natural ecosystems that provide valuable services, including carbon sequestration. Crops also require fertilizers, pesticides and large amounts of water, as well as machinery for planting, growing, harvesting, transporting and processing. If forests are cleared for fuel crops, and if the entire lifecycle of the fuels is taken into account, biofuels don't always reduce overall greenhouse gas emissions. Palm oil, used for biodiesel, is especially bad, because valuable carbon sinks like peat bogs and rain forests are often destroyed to grow palms.

Using better farming methods and more efficient feedstocks and growing fuel crops on land that isn't good for growing food can reduce land use and climate impacts. For example, fast-growing grasses, agricultural and forest-industry wastes, and even household wastes can be used rather than crops like corn that are normally considered food. Some feedstocks are more efficient at producing energy than others. Ethanol from canola and sugarcane is better than from corn, as it delivers more energy compared to what's required to produce the fuel.

Cellulosic materials, including switchgrass and agricultural and forestry wastes, are even more efficient than sugar- and starch-based fuel stocks. They produce fewer greenhouse gases and don't normally displace food crops, but the process of converting cellulose to ethanol is more difficult than turning starch and sugars from corn or sugarcane to fuel. Some studies show switchgrass ethanol can produce 540 per cent more energy than that required to produce the fuel, compared to just 25 per cent more for corn-based ethanol. Experimental biofuels made from biomass like algae, as well as genetically synthesized organisms, show a great deal of promise, as they're efficient and can be produced without large land bases.

Biofuels can play an important role in reducing greenhouse gas emissions, especially for applications like long-haul trucking and possibly air travel. Biodiesel and gasoline mixed with ethanol are already widely available. Research into new types of biofuels is also important, but the massive amounts of land, biomass and water required to produce conventional biofuels mean they aren't a panacea. We can get further in transportation by focusing on fuel efficiency and conservation, increased public transit and other alternatives to private automobiles, and shifting to electric vehicles, especially as clean electricity sources become more widely available.

July 28, 2016
http://www.davidsuzuki.org/blogs/science-matters/2016/07/will-growing-our-fuels-drive-us-to-a-cleaner-future/

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8 Comments

Aug 09, 2016
11:44 PM

i urge you to look into the extremely rapid advances being made in the production of high density, carbon NEGATIVE fuels via solar catalyitics using new nano materials. Such solar fuels can and will be a produced at energy efficiencies that far exceed those of natural photosynthesis

This is but one example from only the last week or so http://phys.org/news/2016-07-breakthrough-solar-cell-captures-carbon.html

There have been dozens of such breakthroughs in the last 5 years. These fuel production techs WILL compete economically with fossil fuel extraction much sooner than most expect

Aug 09, 2016
11:50 AM

In response to Paul’s comment, hemp falls under “cellulosic materials”. The Foundation has nothing against hemp and in fact promotes it’s use as an eco-friendly material.

Aug 05, 2016
9:20 AM

The problem of switching away from fossil fuels is entering a great divide, one between urban and rural.

Those living in urban environments have many more alternatives. They can take public transit. Small electric commuter vehicles make sense. Distances are short. Energy is plentiful and reliable.

But in rural areas, none of that applies. The bigger problem is that, while everyone concentrates on unnecessarily finding solutions for urban dwellers, few people are concentrating on the rural dwellers. But because of market mechanics, it’s the rural dwellers who are key for the desired change.

Consider the farmer. What powers his/her tractor? What powers the truck which brings those crops to the urban centres. Right now, fossil fuels are the most cost-effective power supply for the farmer. If it’s too expensive for the farmer, it’s too expensive for the urban dweller as well. But if it’s too expensive for the farmer, what happens to our food supply?

Find a suitable eco-friendly solution for the farmers, and everything else will fall into place. This is the last piece of the puzzle we’re missing and it’s critical we find it. But too few people are even thinking about it.

Aug 01, 2016
12:47 PM

We often forget that using fuels in internal combustion engine produces air pollution regardless of the origin of the fuel. NOx and PM are produced at the same rate regardless if diesel or biodiesel are used. While air pollution can be reduced with the use of ethanol, using ICEs will only buy us some time before we pollute our air beyond the natural ability of the environment to recover. We need to educate the public about the coupled effects of using combustion to create power: long term impact with GHGs and immediate impact with air pollution that affect our health. Biofuels are not the anwser and the best short term and long term solution is renewable electrification of the world.

Jul 30, 2016
12:07 PM

“We can get further in transportation by focusing on fuel efficiency and conservation, increased public transit and other alternatives to private automobiles,”

first we have demonize the private car (especially in cities) as we successfully did and continue to do with tobacco ban all advertising for it on tv mags and newspapers plenty of pro-car propaganda available @ dealerships associate every car brand with air and noise pollution, congestion, violence, killing, maiming, obesity, road rage etc fuel problem solved

Jul 29, 2016
10:40 AM

All these words about bio-fuel and no mention of hemp? What does David Suzuki have against hemp?

Jul 29, 2016
6:59 AM

This is great article for 2 reasons: 1. It shows that our bi fuels currently in production (not the experimental ones) are a major source of concern for taking so much land that can be used for food production in a world where many people suffer from a chronic lack of food. 2. There are bio fuels that once reaching the stage of mass production will be less damaging to the environment and our need for food.

By the other hand bio fuels are intended only to replace conventional fuels, leaving the humankind clinging on the same old technology. So from this perspective they are blocking the way to adopting new technologies. The “cleaner” and less environmentally ones should be used only to bridge the gap until new technologies with 0 carbon emissions are available.

Jul 29, 2016
5:52 AM

I use biofuel that is made from old used cooking oil, like for frying fish or French fries. In this way, I am using a waste material to power my car.

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