Biofuels Do More Harm Than Good
We all want biofuels like ethanol, biodiesel, and biogas to be a carbon neutral, renewable energy. We want them to be a cute loop whereby crops pull carbon dioxide out of the atmosphere as they grow, those crops get turned into biofuels, and then those biofuels get burned to release their energy, returning exactly that same amount of carbon dioxide to the atmosphere, totally no harm, no foul, no additional global warming.
But I don’t know why anyone ever thought, much less continues to insist on thinking, that this is all there is to the story.
Because of course it takes energy, land, and resources to grow crops and process them into biofuels. Processing biofuels also produces waste that needs to be disposed of—and that can be literally millions of barrels of liquid waste a year from a single facility—but that’s a whole other story that hardly anyone is talking about or researching the carbon or other environmental cost of.
The True Cost of Biofuels
When you honestly account for the amount of greenhouse gas released to the atmosphere as part of the production and processing of biofuels, none of the biofuels turns out to be carbon neutral. Not even close. To give you an example based on one of the biggest biofuels, ethanol can be so far from carbon neutral, to use it as a fuel is to be emitting nearly one third more carbon dioxide than you would be emitting if your fuel was strictly fossil gasoline.
And that’s even before you take into consideration the greenhouse gas added to the atmosphere from all the land that has been deforested to make way for the last two decades’ massive expansion in biofuel crops.
That means that biofuels are not only failing to live up to their environmental promises, as a cure, they are actually worse than the disease.
What probably started out as good intentions and an oversimplified view of how it would work, got grabbed by entrepreneurs and turned into an explosively growing industry that is making money hand over fist—often with government subsidies—while driving up food prices, accelerating rates of deforestation, and causing more global warming than if we weren’t substituting biofuels in for fossil fuels.
Worse, by investing in a technology that isn’t going to help us get to net zero carbon emissions ever, much less as soon as possible, we’re stopping ourselves from fully investing in technologies and changes in our economies and own behavior that would actually help us reach net zero emissions of greenhouse gases to the atmosphere. And that is just adding to the tragedy that is biofuels.
The Problem That Biofuels Are Supposed to Solve
The Problem That Biofuels Are Supposed to Solve Is That Transportation Adds a Lot of Greenhouse Gas to the Atmosphere
Right now, 91% of transportation is fueled by fossil fuels. This means planes, trains, and automobiles, and cruise ships, container ships, and fishing boats, as well as pipelines that pump along products like oil and natural gas. All of this locomotion takes energy.
At the moment, this energy comes almost entirely from the combustion of fossil fuels. As a whole, the transportation sector emits 8.0 billion tons of carbon dioxide (also known as 8.0 gigatons CO2 or 8.0 GtCO2) per year, at least as of 2022, which was, at the time of this writing, the most recent year for which we have a solid estimate.
That makes transportation responsible for nearly a quarter of the current 34.6 billion tons of carbon dioxide we emit to the atmosphere every year solely by burning fossil fuels. Although changes in our use of land, such as deforestation to make way for more soybean fields or palm oil plantations, also adds carbon dioxide into the atmosphere, if we’re ever going to hit net zero carbon emissions to the atmosphere, much less by 2050, transportation needs to find ways to make itself carbon neutral ASAP.
How ASAP is ASAP? Back in 2021, the International Energy Agency (IEA) released a report on how we could reach net zero by 2050 aggressively enough to have a good chance of holding total global warming below 1.5°C. In their proposed Net Zero Emissions (NZE) scenario, by 2050, the transportation sector needs to reduce its total consumption of fuel by about 30% and shift down to no more than 10% of this fuel being fossil fuel. Most sensibly, that would mean running 90% of our transportation off of renewable electricity. But other people see a role for biofuels.
Keeping transportation on track for us to reach net zero by 2050 calls for carbon dioxide emissions from transportation to be falling by 3% a year starting a couple of years ago already, to bring yearly emissions down to 6 GtCO2 by 2030. And then we have to keep going to reach yearly emissions of no more than 1–2 GtCO2 from transportation in 2050, all of which will need to be offset by carbon capture and storage so that we are no longer increasing the concentration of greenhouse gas in the atmosphere.
Again, a sensible approach would involve switching over to electric vehicles everywhere where that is feasible and charging those vehicles with electricity generated via wind and solar power. For the situations where running on batteries isn’t feasible—such as aviation, heavy farm equipment, and long–distance trucking—we should be switching over to using hydrogen fuel produced truly renewably. But many people would like to see biofuels playing a big role in decarbonizing transportation, as well as in the generation of heat and electricity for industrial and domestic use.
As an added note, as time goes by, global warming accelerates, and the side effects like deadly heatwaves, droughts, deluges, and wildfires become more troublesome. With each passing day of insufficient progress in decreasing our emissions of greenhouse gases to the atmosphere, the more urgent our need to, not just hit our targets for reductions in emissions, but exceed them.
Making matters worse is that the targets, set very conservatively by scientists who did not want to be doommongers, are looking less and less likely to keep us under 1.5°C of long term global warming. On the short term, global warming has, in fact, already topped 1.5°C, for the year from February 2023 to January 2024. But as a decadal average, which is the benchmark that’s used when talking about reaching 1.5°C of global warming, we’re not there yet. Don’t party about that though, for we are likely to reach 1.5°C of long term warming within the next five years.
That we are about to fail to keep long term global warming below 1.5°C is, however, not reason to just give up and let ourselves continue to emit greenhouse gases willy nilly. Because every little bit hotter we warm climate, the worse it will be for us, being about to breach 1.5°C is reason to actually finally take meaningful action toward eliminating our addition of greenhouse gas to the atmosphere. By meaningful action I mean through a rapid changeover to using renewable energy for basically everything.
As mentioned earlier, this is where the people in the biofuel industry—and to a distressing extent, in government and intergovernmental agencies, where they should know better—say they would like biofuels to step in to help us out.
Biofuels, the Dream vs Biofuels, the Reality
The dream of biofuels is that when you burn them in your car, jumbo jet, or heating system, you’re just releasing carbon dioxide that the plants that were used to make the biofuels removed from the atmosphere when they grew just last year or maybe the year before. That would make them a perfectly closed loop that wouldn’t drive an increase in greenhouse gas concentrations in the atmosphere.
But it is simply not this simple, no matter how much proponents of biofuels insist it is.
Never mind that if we let the land we’re using to grow biofuels grow back into the forests, jungles, and moors they used to be, this land would take up and store more carbon than biofuels grown on it would ever save us from emitting, even by the best case scenario estimates, which are woeful overestimates, of how carbon neutral biofuels are. That’s just the next dimension to the problem. The main problem is that producing biofuel crops, processing them into biofuels, and then distributing biofuels to consumers costs energy and resources and has environmental consequences.
Tractors, harvesters, and all the other big, industrial pieces of equipment that are needed to plant, tend, and harvest biofuel crops, run on fossil fuels. Even people who are gung–ho about running vehicles on renewable electricity admit that electric farm vehicles are not feasible.
Batteries sufficient to power such heavy machinery for the lengths of time they need to be used would render them far too heavy for use on fields. Then there’s all the machinery needed to process matter into biofuels that then have to be delivered to the consumer. This also all currently runs on fossil fuels. And fossil fuels have both a major carbon dioxide footprint and a major methane footprint, because gas and oil extraction and refining vents a lot of methane out of the earth and into the atmosphere.
So you can’t just say the carbon dioxide emitted to the atmosphere during biofuel use equals the carbon dioxide removed from the atmosphere via photosynthesis when the biofuel crop grew. A more accurate equation is the carbon dioxide (and other greenhouse gases) added to the atmosphere during biofuel production and use is greater than the amount of carbon dioxide removed from the atmosphere via photosynthesis during the growth of the biofuel crop.
To put it bluntly, biofuels are not carbon neutral, and that’s even before you factor in the emissions associated with change in land use (which is a nice way of saying deforestation, which the expansion in the biofuel industry has driven a lot of). In many cases, biofuels are not even less carbon emitting than traditional fossil fuels.
But there are biofuels and then there are biofuels. We should probably talk about the different kinds separately.
What Do We Even Mean By a Biofuel?
The term biofuel refers to fuels that have been produced from recently grown biomass.
At its broadest, biofuel’s definition includes wood, which is still quite heavily used as a fuel. Nearly a billion people on the African continent rely on wood for heating and cooking and, I have to admit, most of my neighbors out here in the north German countryside have wood stoves that keep their living rooms cozy in winter (although they rely on an oil burner or a heat pump for their central heating).
But the biofuels this article refers to are the biofuels produced through the digestion or other chemical transformation of the products and byproducts of agriculture or the cultivation of algae. This means things like bioethanol (generally referred to just as ethanol), biodiesel, biogas (which is a mixture of methane and carbon dioxide), biomethane, syngas (which is a mixture of carbon monoxide, hydrogen, and other gases), and various algal-based biofuels.
People who like to talk about biofuels split them into four main categories—first through fourth generation biofuels—which have to do, not with what they are, but how they’re produced.
First Generation Biofuels
First generation biofuels consist of things like ethanol and biodiesel that have been made from edible crops.
To produce first generation bioethanol, carbohydrate rich crops like maize (also known as corn or sweetcorn), wheat, sugar cane, and sugar beets are turned into starchy–sugary feedstocks that are fermented by bacteria in enormous anaerobic digesters to produce ethanol. This bioethanol is then used on its own as a fuel or, most often, it is added to gasoline.
In the production of first generation biodiesel, oil rich crops like soy, rapeseed (also known as canola), and oil palm are processed, through a series of industrial steps, into biodiesel. Biodiesel can be used directly in specialized diesel engines or blended in with petroleum diesel to make mixtures of up to about 5% biodiesel for use in conventional diesel engines.
These biofuels have been immensely popular and over the last two decades, an enormous industry, mainly in North America, South America, Europe, and Asia, has sprung up to produce them.
Unfortunately, these first generation biofuels add to the problems we’re facing rather than help us solve them.
A study that went beyond the typical lifecycle analysis (LCA) that is normally used to assess how carbon neutral a biofuel is, but that overlooks many of the sources of carbon emissions related to biofuels, tracked the flow of carbon through the whole system—fossil fuels, crops, transportation, and biofuels—in the USA between 2005 and 2013 to check the impact of biofuels on America’s addition of carbon dioxide to the atmosphere. Given the time and the place, this meant mostly first generation bioethanol.
What this study found was that the use of this bioethanol as a fuel emitted far more carbon dioxide to the atmosphere than the growing of the bioethanol crops removed. Instead of the balance between carbon dioxide removal and return being close to equal, as the biofuel industry would have you believe it is, the carbon dioxide taken up by the growth of the biofuel crops canceled out only 37% of the emissions related to biofuel production and use.
That’s absolutely dismal, to the point of first generation bioethanol being nearly 30% worse, in terms of carbon emissions, than running a vehicle purely on fossil fuel.
That is a cure that’s worse than the disease, and that’s even before you count the side effects of loss of land area, for wilderness or producing food, associated with growing first generation biofuel crops.
Because first generation biofuels are made from edible crops grown specifically to produce biofuels, they drive up food prices. Instead of using these crops to feed ourselves or the livestock we eat, we’re burning those crops as fuel. The increased demand for these crops, thanks to their use as first generation biofuels, also drives deforestation, as farmers clear more land to plant more biofuel crops, including soy and oil palm, which are already problematic even just as food and feed.
Lastly, even if these biofuels were delivering the “carbon savings” that they aren’t, we could remove more carbon dioxide from the atmosphere by letting the land area we’re using to grow first generation biofuel crops renature itself, converting a sizeable stock of carbon dioxide into long lived biomass and long lived soil carbon in the process.
Second Generation Biofuels
Production of second generation biofuels makes use of leftovers and discards—things like agricultural waste and by-products (like straw and animal waste), used cooking oils, waste wood, woody shrubs grown on wasteland, and even sewage—instead of crops grown specifically to be turned into biofuel. This takes the sting out of the land use and food price issues, but turns out not to make them much more carbon neutral than first generation biofuels.
What’s tricky about second generation biofuels is that the materials they’re made from tend to be richer in components that are hard to ferment, like lignin and cellulose. That makes the processing of second generation biofuels more difficult, time consuming, and costly than the processing of first generation biofuels. The need to clean up the “feedstocks” before they’re processed into biofuel can take a lot of water—and produce a lot of wastewater that then needs to be disposed of in a way that doesn’t cause environmental problems in places that are rural and therefore not necessarily equipped to deal with large volumes of wastewater.
Take, for instance, this example about the proposed injection of millions of barrels of wastewater from the production of a second generation biofuel for use in aircraft (a so called sustainable aviation fuel) into spent oil wells and the concerns of local residents that this will flush petrochemicals into groundwater reservoirs.
The other downside to second generation biofuels is that there is a more limited amount of material available for their production, and so it’s not clear that this could be scaled up to become a meaningful replacement for fossil fuels in the event that second generation biofuels turn out to have lower carbon emissions than fossil fuels.
At the moment, a sophisticated carbon flow analysis is not possible for these fuels. That will have to wait until they dominate the biofuel market. But even the less accurate lifecycle analysis (LCA), which generally errs in favor of carbon neutrality, doesn’t clearly show that second generation biofuels are much of an improvement over fossil fuels. The main problem here is that way too much fossil fuel is consumed during the more intensive processing needed to produce second generation biofuels from their more recalcitrant feedstocks.
Third and Fourth Generation Biofuels
This brings us to the third and fourth generation biofuels, which fall somewhere between never give up, never surrender and what fresh hell is this. Third generation biofuels are made from algal and cyanobacterial biomass. Fourth generation biofuels are—or rather, at this point, more will be than are—made from organisms genetically modified to be better fodder for biofuel production.
In theory, third generation biofuels could be an interesting way to deal with excess nutrients that run off into waterways and cause noxious phytoplankton blooms. The algae would be grown on these waste nutrients in tanks or bioreactors and would convert carbon dioxide into biomass that would be then used to make biofuel.
But there are already problems with people misunderstanding how to produce third generation biofuels in a way that avoids adding carbon dioxide to the atmosphere. There are calls to feed the bioreactors with carbon dioxide captured from industry. But this would not stop that carbon dioxide from being emitted to the atmosphere. It would just fuel a bit of transportation briefly in between and that would not ever suffice to get us to net zero carbon emissions. It would be better to grow the biofuel algae with carbon dioxide from air and take the carbon dioxide captured from industry and store it somewhere permanently away from the atmosphere.
As much as many people don’t like the idea of genetically modified organisms, it will probably be hard to hold industry back from going this route. Because if they can create plants, algae, and cyanobacteria that have a higher than natural photosynthetic efficiency (and can therefore grow faster with less light) or are rich in the compounds they need to make biofuels, they won’t have to spend as much time, money, and energy processing these products into biofuels.
In Conclusion
There is certainly enough to be said about biofuels to fill a couple of books. I’m afraid that this article, although longer than intended, could do little more than scratch at that surface. But if I had to sum up biofuels in four words, they would be more harm than good.
At best, biofuels deliver minimal carbon savings over burning fossil fuels. At worst, they result in even more emissions of greenhouse gases to the atmosphere while simultaneously creating waste streams, driving up food prices, and encouraging deforestation.
To read through the websites of the companies producing biofuels and the articles written by people who want to believe that biofuels are a good way to get us toward net zero carbon emissions is to be shocked (and then infuriated) by the propaganda they contain. Biofuels have grown up from naïve wishful thinking into an explosively growing industry uninterested in whether or not its products are responsible for emitting massive quantities of carbon dioxide and other greenhouse gases to the atmosphere. The biofuel industry seems to be far more interested in the money to be made peddling these questionable wares than it is in making the future a safer, more survivable place to be.