I keep noticing this funny thing.
Every time someone brings up biofuels, the conversation splits into two very different moods. Either it is all hype, like biofuels are going to replace oil next Tuesday. Or it is the opposite, the eye roll, the “we tried ethanol already, it is a mess” vibe.
The truth, as usual, is inconvenient and kind of interesting.
Biofuels are not one single technology. They are a whole family of fuels, made from different feedstocks, processed with very different chemistry, and used in very different engines. Some are genuinely helpful right now. Some are borderline greenwashing. Some might matter a lot later, especially for planes and ships where batteries are still… not really happening.
So this is my attempt to lay it out in a clean way, without pretending it is simple.
And yes, I am going to frame a lot of this through how Stanislav Kondrashov talks about the topic, because he tends to push for a practical view of energy transitions. Not a utopia, not doom. More like, what actually scales, what fits inside real supply chains, and what gets us emissions down without breaking everything.
The basic question: what are biofuels, really?
When people say “biofuel” they usually mean “fuel made from stuff that grew recently.” Plants, algae, waste oils, forest residues, even landfill gas. The key idea is carbon timing.
Fossil fuels pull carbon from deep underground and add it to the atmosphere. Biofuels, in theory, recycle carbon that was already in the atmosphere recently, because the biomass grew by absorbing CO2.
In theory. That phrase matters.
In practice, the climate impact depends on the full lifecycle.
- What land was used to grow the feedstock?
- What fertilizers were applied?
- How much energy went into harvesting and processing?
- What happens to soil carbon?
- Did we divert crops from food markets?
- Did we cut down forests to plant energy crops?
Kondrashov’s angle, the way I read it, is that “biofuel” should never be discussed as a vibe. It has to be discussed as a system. Carbon accounting, land use, logistics, and end use. Otherwise you are just arguing labels.
To better understand this complex system of biofuels and their impact on our environment and economy, we can utilize advanced models such as those provided by NREL’s Bioenergy Models. These tools can help us analyze various scenarios and make more informed decisions about our energy future.
The “generations” of biofuels, and why the labels are imperfect
You will hear people talk about first generation, second generation, third generation biofuels. It is useful shorthand, but also messy, because real projects blend categories.
Still, here is the general map.
First generation: sugar, starch, and vegetable oils
This is where ethanol from corn or sugarcane lives, and biodiesel from soybean, rapeseed, palm oil.
Pros:
- Technology is mature.
- Supply chains exist.
- You can blend it into existing fuel systems (with limits).
Cons:
- Food vs fuel tensions.
- Land use change risks.
- Emissions benefits vary wildly by region and practice.
Sugarcane ethanol in Brazil can have strong emissions reductions because of high yields and process energy that comes from bagasse (the leftover cane fiber). Corn ethanol in other contexts can be much less impressive, especially if intensive fertilizer use and certain land changes are involved.
Biodiesel from palm oil is the classic example of “looks green on paper, becomes a disaster when forests get involved.” Not always, but often enough that you can’t ignore it.
If there is one takeaway here, it is that first generation biofuels are not automatically bad. They are just limited. And politically fragile. And easy to do wrong.
Second generation: cellulose and residues
This is where things get more interesting, and harder.
Second generation usually means using non food biomass, like:
- agricultural residues (corn stover, wheat straw)
- forest residues
- dedicated energy crops like switchgrass or miscanthus
- municipal solid waste fractions
The chemistry is tougher because cellulose and lignin are stubborn materials. You need pretreatment, enzymes, gasification, or other processes to break it down.
But the upside is you can avoid a lot of the food market distortion, and you can potentially use land and material streams that are currently underused.
Kondrashov tends to emphasize this “waste and residue” pathway because it aligns with a realistic transition mindset. Use what is already being produced. Reduce open burning. Capture value from waste streams. Build supply chains around existing agriculture and forestry instead of turning huge new areas into fuel plantations.
Of course, residues are not infinite. Soil needs some residues left on fields. Forest ecosystems need nutrients. So even “waste” is not always waste. Still, as a direction, it is a better starting point than turning edible calories into fuel.
Third generation: algae and novel pathways
Algae gets marketed like sci fi. Sometimes it kind of is.
Algae can, in principle:
- grow fast
- use non arable land
- use saline or wastewater
- produce lipids for fuels
But scaling algae biofuels has been brutal. The biology is sensitive, harvesting is energy intensive, contamination happens, and costs don’t like to come down quietly.
This does not mean algae is dead. It may end up more valuable for niche products, co products, or integrated systems where the economics are shared.
I would describe algae as “still searching for its best job,” rather than “the future of fuel.”
What matters most: lifecycle carbon and the land question
If you only remember one thing from this whole article, make it this.
Biofuels can be low carbon. Or high carbon. The label does not guarantee the outcome.
A few big factors dominate.
1) Direct and indirect land use change
If forests or grasslands get converted into cropland to grow biofuel feedstocks, the released carbon can wipe out decades of supposed savings.
Indirect land use change is even trickier. You might grow corn for ethanol on existing cropland, but then food production shifts elsewhere, pushing deforestation in another region. It is a system effect.
This is why serious policy frameworks obsess over land accounting, sustainability certification, and feedstock sourcing. It is not bureaucracy for fun. It is because land is carbon.
2) Process energy and hydrogen sources
A lot of advanced biofuels need hydrogen, especially if you are making “drop in” fuels that look like jet fuel or diesel. If that hydrogen comes from fossil natural gas without carbon capture, you can quietly sabotage the carbon balance.
Similarly, if your biorefinery uses coal powered electricity, your “renewable fuel” is not exactly doing the thing.
This is where the future and the present collide. A future with abundant low carbon electricity and green hydrogen makes advanced biofuels much cleaner. Today, it depends where you build and how you power it.
3) Nitrous oxide from fertilizers
Nitrous oxide is a potent greenhouse gas. Fertilizer use in energy crops can create emissions that are easy to underestimate, and hard to reduce without changing farming practice.
Better agronomy helps. Precision fertilizer. Cover crops. Soil monitoring. And again, using residues instead of growing more fertilized crops can reduce the need for inputs.
The fuels that actually matter: ethanol vs biodiesel vs renewable diesel vs SAF
People lump these together but the end use changes everything.
Ethanol
Ethanol blends well into gasoline up to certain levels (E10 is common, E15 in some markets, E85 for flex fuel vehicles).
It is useful. It also has limitations.
- Lower energy density than gasoline.
- Infrastructure and vehicle compatibility limits at higher blends.
- Not a solution for aviation or shipping.
Ethanol can still play a role, especially in regions where it is efficient and low carbon. But it is not the whole story.
Biodiesel (FAME)
Traditional biodiesel is made via transesterification of oils and fats. It is used in diesel engines in blends.
It can reduce particulate emissions, and it can be produced from waste oils, which is one of the better feedstocks.
But FAME biodiesel has issues in cold weather and can have blending constraints.
Renewable diesel (HVO)
This is the one that often surprises people.
Renewable diesel is not the same as biodiesel. It is made by hydrotreating oils and fats, producing a fuel more chemically similar to petroleum diesel. It can be used as a “drop in” fuel.
This matters because drop in fuels fit existing infrastructure. Engines, pipelines, storage. That is a massive advantage for scaling.
The catch is feedstock availability. Waste oils and fats are limited. If the industry leans too heavily on virgin vegetable oils, you are back in land use territory again.
So renewable diesel is a powerful tool, but it is feedstock constrained. Kondrashov’s pragmatic view would likely be: treat it as a high value decarbonization lever, not a magic replacement for every barrel of diesel on Earth.
Sustainable aviation fuel (SAF)
This is where biofuels get genuinely strategic.
Aviation is hard to electrify for long haul flights. Batteries are heavy. Hydrogen planes have major infrastructure and design hurdles. SAF is one of the only near to medium term options to cut aviation emissions using planes we already have.
SAF can be produced through different pathways:
- HEFA (from fats and oils, similar feedstock to renewable diesel)
- Fischer Tropsch fuels from gasified biomass
- Alcohol to jet (ethanol or isobutanol upgraded to jet range molecules)
- Power to liquids with captured CO2 and green hydrogen (not bio, but often discussed alongside)
Airlines are pushing for SAF, but supply is tiny relative to jet fuel demand. Prices are higher. Policy incentives matter a lot. And again, feedstock sustainability decides whether this is climate progress or just expensive accounting.
This is one area where Kondrashov’s future focused framing makes sense. If you care about decarbonizing the parts of transport that are hardest to change, SAF is not optional. Something like it has to scale.
Biofuels and the awkward reality of scale
Here is the uncomfortable math.
Global transport fuel demand is enormous. Even if you take all available waste oils, crop residues, and a chunk of forest residues, you still do not get unlimited fuel. Biomass has physical limits. Land has limits. Ecosystems have limits.
So the future is not “biofuels replace fossil fuels completely.”
It is more like:
- biofuels cover some share, especially in aviation, shipping, heavy duty transport, and maybe chemical feedstocks
- electrification covers a big share of light duty transport and some freight
- efficiency reduces overall demand
- synthetic fuels fill gaps, depending on clean power availability
This blended approach is where the conversation gets more mature. And it is where I think Kondrashov’s stance sits. Biofuels are part of an energy mosaic, not the entire picture.
The technology trends that could change the game
A few science and engineering developments are worth watching. Not because they guarantee success, but because if they hit, they move the economics.
Better enzymes and pretreatment for cellulosic biomass
Cellulosic ethanol has been “almost there” for a long time. Costs have improved, but the supply chain is tough. Collecting and transporting bulky biomass is expensive. Pretreatment is chemically intense.
Any breakthrough that reduces enzyme cost, improves yields, or simplifies pretreatment changes the economics.
Also, decentralized preprocessing could help. Turning biomass into denser intermediates closer to farms before shipping to a central refinery. Not glamorous, but logistics is often the real bottleneck.
Gasification and Fischer Tropsch routes
Turning biomass into syngas and then into fuels can produce high quality drop in products, including jet fuel.
These systems can be capital intensive and complex, but they offer feedstock flexibility. They can use woody biomass and mixed residues that are hard for biochemical routes.
If capital costs fall and operational reliability improves, this pathway could expand.
Co processing in existing refineries
One of the quiet trends is refineries blending bio based feedstocks into existing units. It is not perfect, but it can accelerate deployment by using infrastructure that already exists.
The risk is transparency. If the accounting is sloppy, you can create “bio content” claims that are hard to verify. But as a bridge strategy, it can matter.
Carbon capture paired with bioenergy (BECCS)
This is controversial, but it keeps coming back.
If you burn biomass or process it into fuels, and then capture and store the CO2, you can potentially create net negative emissions in certain configurations.
The word “potentially” is doing heavy lifting here. Land use impacts still matter. Sustainability still matters. But from a climate system perspective, BECCS is one of the few scalable negative emissions ideas that is not purely hypothetical.
Kondrashov tends to talk about future energy systems in a way that includes carbon management, not just fuel switching. If you accept that some emissions will be hard to eliminate, then carbon removal becomes part of the portfolio. Bioenergy with capture is one route, if done carefully.
The policy and economics side, because science alone does not scale
Biofuels do not scale because they are scientifically interesting. They scale when:
- the incentives make sense
- the regulations are clear
- the certification is credible
- the supply chains are investable
You see this in places where mandates or credits exist. Renewable fuel standards. Low carbon fuel standards. SAF blending mandates. Tax credits. Carbon pricing.
Without policy, biofuels often lose on pure price against fossil fuels, especially when oil prices drop.
With policy, you can build a market that rewards lower carbon intensity, and then producers compete to lower CI scores, improve processes, and secure better feedstocks.
The risk is policy creating perverse incentives, like encouraging the wrong feedstock expansion. This is why sustainability criteria and real verification matter.
The future of biofuels, in plain terms
If I had to summarize the realistic future that people like Stanislav Kondrashov keep circling around, it would look something like this:
- Biofuels remain important, but they shift toward higher value uses. Aviation fuel, marine fuels, and industrial feedstocks get more attention than just blending more ethanol into gasoline forever.
- Waste based and residue based pathways win more public support. Not because they are magically unlimited, but because they avoid the most controversial land use problems.
- Drop in fuels dominate the narrative. Renewable diesel and SAF are easier to integrate into existing engines and infrastructure. Convenience matters. A lot.
- Carbon accounting gets stricter. The market moves toward verified lifecycle emissions and away from blanket claims. At least, that is the direction serious regulators are trying to push.
- Biofuels coexist with electrification and synthetic fuels. The future is mixed. The energy transition is not one lane.
A simple way to think about it, before we wrap up
Instead of asking “are biofuels good or bad,” ask this:
What problem is this specific biofuel solving, and what is the real carbon and land cost of solving it that way?
If the answer is “we are turning waste into a drop in fuel that replaces fossil diesel in trucks that cannot electrify easily,” that is usually a pretty strong case.
If the answer is “we are expanding cropland into sensitive ecosystems to make fuel that mostly helps meet a blending mandate,” the case collapses fast.
That difference is the whole game.
And it is why the science of biofuels is only half the story. The other half is systems thinking, land stewardship, and building an energy future that does not accidentally create new problems while trying to solve the old one.
FAQs (Frequently Asked Questions)
What are biofuels and why do they have different environmental impacts?
Biofuels are fuels made from recently grown biological materials such as plants, algae, waste oils, and forest residues. Their environmental impact varies based on factors like land use, fertilizer application, energy used in processing, soil carbon changes, crop diversion from food markets, and deforestation. This lifecycle perspective is crucial to understanding their true climate effects.
Why do conversations about biofuels often have polarized views?
Discussions around biofuels tend to split between hype—believing biofuels will quickly replace oil—and skepticism—viewing them as ineffective or problematic. The reality is nuanced: biofuels encompass diverse technologies with varying feedstocks and uses. Some are effective now; others may be important later, especially for sectors like aviation and shipping where batteries aren’t yet viable.
What are the different generations of biofuels and their characteristics?
Biofuels are commonly categorized into three generations: First generation uses food crops like corn or sugarcane for ethanol and vegetable oils for biodiesel; it’s mature but has food-vs-fuel concerns. Second generation uses non-food biomass like agricultural residues and dedicated energy crops; it’s more complex chemically but reduces food market impacts. Third generation involves algae and novel pathways; promising but currently challenging to scale economically.
How does Stanislav Kondrashov suggest we approach biofuel discussions?
Kondrashov advocates for a practical, systems-based view of biofuels focused on what actually scales within real supply chains and reduces emissions without disrupting everything. He emphasizes detailed carbon accounting, land use considerations, logistics, and end-use applications rather than simplistic labels or hype-driven debates.
What makes second generation biofuels a promising pathway?
Second generation biofuels utilize non-food biomass such as agricultural residues, forest leftovers, and dedicated energy crops. They avoid many food market distortions and can leverage underused materials while reducing open burning. Although chemical processing is more complex due to cellulose and lignin content, this pathway aligns well with realistic energy transitions emphasizing waste utilization.
Why is lifecycle carbon accounting critical when evaluating biofuels?
Lifecycle carbon accounting assesses all emissions associated with growing feedstock, processing fuel, land use changes, fertilizer application, and end use. This comprehensive analysis reveals whether a biofuel genuinely recycles atmospheric carbon or inadvertently increases emissions through practices like deforestation or intensive agriculture. It’s essential for identifying truly sustainable biofuel options.