Turning Frost-Resistant Crops into Renewable Gas
In the icy embrace of boreal regions, a green energy revolution is quietly taking root—transforming short growing seasons into sustainable power.
Imagine a world where the very crops that withstand the harsh, cold climates of the world's northern regions could power our homes, fuel our vehicles, and fertilize our fields. This isn't science fiction—it's the promising reality of biogas production from energy crops specifically bred and grown in boreal conditions. As the world scrambles to transition away from fossil fuels, researchers in Finland and other boreal regions have been quietly investigating which crops can pull double duty: thriving in cold climates with short growing seasons while producing substantial amounts of renewable biogas. Their findings are revealing an unexpected energy source that could transform the renewable landscape for northern countries.
Biogas is an environment-friendly, renewable energy source produced from decomposing organic matter, such as food, animal waste, crop residue, and energy crops. It combines methane, carbon dioxide, and small quantities of other gases through a natural process called anaerobic digestion—where microorganisms break down biodegradable material without oxygen 6 .
The global biogas market reached $74.4 billion in 2024 and is projected to grow steadily, driven by increasing demand for renewable energy 6 .
The International Energy Agency (IEA) estimates that nearly 1 trillion m³ of natural gas equivalent of biogases could be produced sustainably each year using today's organic waste streams—an amount equivalent to one-quarter of global natural gas demand. Yet currently, only 5% of this potential is being utilized 9 .
Boreal regions—spanning parts of Canada, Scandinavia, Russia, and northern areas with cold temperatures and short growing seasons—present unique challenges for energy crop production. The conventional energy crop superstar, maize (corn), typically requires warm conditions and long growing periods. But what if crops could be identified that not only survive but thrive in boreal conditions while producing impressive amounts of biogas?
Researchers at the University of Helsinki set out to answer this exact question. Their groundbreaking work has focused on evaluating different crops for their suitability as raw materials for biogas production specifically under boreal conditions 5 . The implications of their research are significant—if productive energy crops can be grown in these climates, it could open up new economic opportunities for farmers, reduce reliance on energy imports, and create a circular economy where crops are grown for both food and energy purposes.
Crops must withstand freezing temperatures and short growing seasons characteristic of boreal climates.
Successful energy crops produce substantial biomass even under challenging growing conditions.
The ultimate measure of success is the conversion efficiency of crop biomass into methane gas.
To understand which crops hold the most promise for boreal biogas production, researchers conducted detailed field trials and laboratory analyses. The study compared three potential energy crops: maize, fibre hemp, and faba bean 5 .
The research team cultivated these crops in field trials at the University of Helsinki campus at Viikki (60°14′ N, 25°2′ E)—firmly within boreal territory. The crops were grown during 2007-2008, with careful monitoring of their growth characteristics, biomass yields, and response to boreal conditions.
Once harvested, the plant materials underwent chemical composition analysis to determine their suitability for biogas production. Researchers measured the levels of key components including:
The biogas production potential was then tested through methane potential assays—laboratory tests that simulate the anaerobic digestion process and measure the resulting methane gas production 5 .
| Crop | 2007 Dry Matter Yield (t ha⁻¹) | 2008 Dry Matter Yield (t ha⁻¹) | Nitrogen Fertilizer Requirement |
|---|---|---|---|
| Maize | 25.0 | 15.0 | High |
| Fibre Hemp | 14.0 | Not specified | Moderate |
| Faba Bean | 9.5 | Not specified | Low (nitrogen-fixing) |
The findings revealed several surprises that could shape the future of biogas in cold climates:
—despite its reputation as a warmth-loving crop—produced remarkably high biomass yields under boreal conditions, reaching over 25 tons of dry matter per hectare in the favorable 2007 season. Even in the cooler 2008 season, it still yielded approximately 15 tons per hectare 5 .
demonstrated solid biomass production and particular promise for ethanol production, with the highest theoretical ethanol yield per hectare among the studied crops. Its structural complexity meant that more extensive milling significantly increased its methane yield 5 .
produced less biomass but offered significant advantages as a nitrogen-fixing legume, requiring minimal nitrogen fertilizer—an important economic and environmental consideration. Its methane yield per ton of volatile solids was competitive with the other crops 5 .
| Crop | Methane Yield (m³ CH₄ t VS⁻¹) | Methane Yield Per Hectare (m³ CH₄ ha⁻¹) | Need for Fertilizer |
|---|---|---|---|
| Maize | 340 | 5,100-8,500 | High |
| Fibre Hemp | 270 | Approximately 3,780 | Moderate |
| Faba Bean | 320 | Approximately 3,040 | Low |
Perhaps most importantly, the research demonstrated that all three crops could be successfully cultivated for energy purposes in boreal conditions, each with different strengths and trade-offs 5 .
The process of transforming plant material into biogas relies on anaerobic digestion—a complex biochemical process where microorganisms break down organic matter in the absence of oxygen. This process occurs in four key stages :
Large organic polymers (carbohydrates, proteins, fats) are broken down into smaller molecules.
Acid-producing bacteria convert these smaller molecules into volatile fatty acids.
Simple molecules from acidogenesis are further digested to produce hydrogen and acetic acid.
Methane-producing archaea form methane from the intermediate products.
The efficiency of this process depends on multiple factors including temperature, the chemical composition of the feedstock, and the presence of necessary microorganisms. In boreal conditions, maintaining optimal temperatures for anaerobic digestion may require more energy input, making the selection of high-yielding crops even more critical.
| Component | Maize | Fibre Hemp | Faba Bean |
|---|---|---|---|
| Neutral Detergent Fibre (NDF) | 46.9% | 76.4% | 36.1% |
| Acid Detergent Fibre (ADF) | 28.8% | 66.6% | 30.8% |
| Acid Detergent Lignin (ADL) | 3.8% | 11.4% | 7.1% |
| Starch | 21.3% | Not detected | 31.8% |
| Water-Soluble Carbohydrates | 13.6% | 1.3% | 9.2% |
Understanding how researchers evaluate biogas potential requires a look at the essential tools and reagents they use:
A highly accurate mathematical model that effectively assesses digester performance capabilities 7 .
A standardized method to test the anaerobic degradability of different organic wastes and compare their methane conversion efficiency 7 .
Determination of the combustible portion of the substrate that can be converted to biogas, measured by mass lost during ignition at 950°C 4 .
Measures the amount of organic matter in a substrate that can be oxidized, helping predict biogas production potential 7 .
Including ammonia and phosphate measurements, as these nutrients are essential for microbial growth but can become inhibitory at high concentrations .
The potential of energy crops in boreal regions extends far beyond laboratory measurements. When implemented at scale, these systems could deliver multiple environmental benefits:
By replacing fossil fuels with renewable biogas
Through the use of agricultural residues
Through the use of digestate—a nutrient-rich byproduct of biogas production that serves as an excellent biofertilizer 9
The IEA notes that maximizing biogas potential from wastes and utilizing the resulting digestate could satisfy approximately 15% of the EU's projected fertiliser needs by 2050 9 . For boreal regions with agricultural sectors, this represents a significant opportunity to create circular economies where crops are grown for both food and energy, with residues from both processes being utilized efficiently.
From an economic perspective, biogas production could provide new revenue streams for farmers in boreal regions through both the sale of energy and the production of biofertilizers. While initial investments in biogas infrastructure can be substantial, the long-term benefits of energy independence and diversified farm income could make the transition worthwhile.
Despite the promising research, several challenges remain for widespread adoption of energy crops for biogas in boreal regions:
The IEA's cost analysis indicates that government support and carbon pricing can help bridge the economic gap. For instance, with a carbon price of USD 50 per tonne, 280 billion cubic metres of biomethane could compete with natural gas on a global scale 9 .
The pioneering work evaluating energy crops for biogas production in boreal conditions reveals an exciting truth: the cold northern regions of our planet hold significant untapped potential for renewable energy production. While maize shows particular promise for methane production, fibre hemp and faba bean also offer compelling benefits that may suit different agricultural contexts and priorities.
As research continues and technology advances, we may see a future where boreal landscapes not only produce food and timber but also contribute significantly to sustainable energy systems. The path forward will require collaboration between farmers, researchers, policymakers, and energy providers—but the foundation has been laid for a biogas revolution in the world's cold climates.
The evidence suggests that the question is no longer if boreal regions can become significant producers of biogas from energy crops, but when and how they will fully harness this sustainable energy source for the benefit of both their economies and the global environment.