Cannabis Biofuel: is it a Feasible Solution?
Today, one of the most common forms of biofuel is biodiesel. In “What is Biodiesel” we already discussed its origins and evaluated pros and cons of its use in “Drawbacks of modern production of Biodiesel”.
Today we would like to address
– what is the role of the Cannabis plant in the Biodiesel and green energies scenario?
– how can this plant help us to move towards a more sustainable-energy world?
One of the most interesting alternative to traditional and common feedstocks for biodiesel and biofuels in general is Cannabis.
Why Cannabis is an interesting raw material for biodiesel?
Biodiesel can be produced from a great variety of feedstocks: the choice for the best one depends largely on geography, climate and economics. For this reasons, today rapeseed and sunflower oils are mainly used in Europe, soybean oil and animal fats in the United States, palm oil in tropical Countries and corn and sugarcane in Brazil.
Thus, the choice of feedstock used for Biodiesel production does not follow criteria that pinpoint the most efficient raw material that could be grown for this purpose, but it’s rather based on the most available feedstock currently present in a Country.
In contrast to palm oil, sugar cane, maize, etc., Cannabis is a highly adaptable, fast-growing, annual plant that can be cultivated at most latitudes. In addition, Cannabis is oneof the few plants that produces high yields of both oil and biomass, which means it can be used to produce both biodiesel and bioethanol.
For this reasons, Cannabis has the potential to form the basis of a revolutionary fuel industry, internationally distributed because the plant can be efficiently grown almost anywhere, yet locally determined because consumers and communities can also be producers.
What kinds of green energies can be produced from the Cannabis plant?
There are many applications for the Cannabis plant in the textile, food, medical and building sectors, but its uses in the energy sector are not well known by the general public and not limited to biodiesel which is just one of many.
Examples of energy products that can be produced from Cannabis are: [3] , [4]
– heat produced from the combustion of briquettes or pellets made of Cannabis hurds and stems;
– electricity from Cannabis biomass through the use of Combined Heat and Power (CHP) engines;
– biogas from anaerobic digestion, a common natural process based on microbial degradation of biomass in the absence of oxygen, which generates methane;
– bioethanol obtained through fermentation, which is another natural process used by man since ancient times;
– biodiesel from Cannabis seed oil where the oil contained in the seeds is converted to biodiesel by a transesterification process with methanol;
Between the advantages of using Cannabis as a resource for biofuels we can now highlight at least 4 important points:
1) Cannabis produces annually high yields of both oil and biomass;
2) Cannabis can be efficiently used in crop rotations substituting the common crops, so no new arable land would be necessary;
3) Cannabis requires little pesticide;
4) Cannabis has the potential to decrease pesticide use in succeeding crops; [5] Today, the main feedstocks for biofuels like maize, soybean and sugar beet, require large quantities of pesticides so a biofuel production 100% based on these crops may not be a real green solution.
In fact, a responsible way of growing green oil crops should take under consideration the amount of pesticides the cultivar requires.
Pesticide use have a strong influence on:
a) the energy input in cultivation (due to high energy requirements for pesticide production)
b) the entire ecosystem
If you are interested in natural pesticides solution, check out our video on “Push-pull technologies, an eco friendly pest management system”.
In contrast with common feedstocks, Cannabis:
– can be grown even on “marginal” lands because it has low input requirements for cultivation;
– can be efficiently used as a preceding crop for the cultivation of cereals since it increases their yields from 10-20%;
– is a pest-resistant, highly adaptable plan;
– even in monoculture fields, it allows for a low pesticide use if followed by a well designed crop rotation;
– it is an annual plant that fits well in crop rotations and it has the ability to suppress soil pathogens opening the path for an healthier soil; [6], [7]
Cannabis biofuel: the advantages
– low pesticide requirements;
– good weed competition (less need for pesticides);
– suitability as break crop in cereal-oriented crop rotations;
– high biomass yield in relatively short time;
– low input requirements;
– economically feasible even for small-scale cultivation areas;
– unlike perennial crops it does not require any long term commitment for its cultivation;
All these aspects may be key elements for a more sustainable biofuel production from biomass in the next future.
So, why Cannabis is not already the main source for biofuels worldwide?
Today, after decades of prohibition, Cannabis is getting back to the legal market claiming its share in many sectors. Laws are changing and people has started to look at different alternatives.
But the reason why Cannabis is still not widely used for biofuels is very simple: today, the value of the crop’s fibre and seed is greater than the value of energy it would produce.
Economical competition on the energy level with petroleum-based fuels or other biofuels can be very challenging for Cannabis. Given the actual situation, incomes for farmers are greater if they sell their seed and fibre crops separately, which can better compete on the food and textile levels.
Right know, without the necessary infrastructure and subsidies by governments aiming to favour green energies instead of fossil fuels, the production of biofuels from Cannabis struggles to be profitable.
Cannabis has a good energy output-to-input ratio and is an above-average energy crop but it has been developed little as an industrial energetic crop over the past decades compared to other crops.
However, in comparison with other well-established food crops, Cannabis still has a great potential for improvement on both increased biomass yields and better conversion efficiencies into biofuel so we can be optimist for the next future.
What are Cannabis hurds and how can they contribute to make energy crop more competitive?
As we said, industrial Cannabis hemp is mainly cultivated for its high-quality fibres and high-value seed oil, but today the hurd, the woody core of the plant which constitutes up to 70% of the dry stalk matter, is a cellulose waste.
A better use of this waste material may contribute to rank Cannabis at the top of the most interesting plants for energy production. In fact, the efficient liberation of sugars from lignocellulosic biomass waste (like Cannabis hurds) not only would decrease solid waste handling, but it would also produce value-added biofuels and bio-based products such as bio-plastics.
Cannabis hurds are a form of lignocellulosic biomass which constitutes the most common raw material present in the world. Differently from wood species, Cannabis is an annual plant and its hurds chemical composition is pretty unique:
– on one hand it is very similar to that of wood species with a high content of carbohydrate (cellulose and hemicelluloses) containing sugars;
– on the other hand it has a very low percentage of lignin, thus favouring the extraction of cellulose from the plant material;
So far, Cannabis hurds still only have minor applications such as animal bedding, garden mulch or as a component of light-weight concrete; Cannabis hurds are an agroindustrial by-product with a high carbohydrate content so they are an excellent candidate for second-generation ethanol production.
Thus, the use of Cannabis hurds as a feedstock to produce ethanol may increase Cannabis attractiveness as a resource for biofuel and replace petrol as a transport fuel.
Conclusions:
Today, technologies to recover up to 96% of the sugar present in Cannabis hurds to transform it in ethanol already exist, but the problem is that they have not been introduced at an industrial scale yet.
Why Cannabis cultivation has the potential to make us move towards a greener world?
– it can promote environmentally beneficial methods of agriculture (especially via crop rotations), which could actually help secure a long-term strategy of land management, ensuring that food
shortages do not occur;
– it can generate the basis for a green economy, taking advantage of the many bio-products that can be derived from the Cannabis plant;
– it can be used for either food, fibre or as a bioremediation crop to restore unproductive land back to agricultural productivity while at the same time providing industrial quantities of cellulose for energy production;
The world urgently needs a replacement for fossil fuels, and cellulose derived ethanol seems to be an ideal industrial successor to them. With Cannabis we would replace an unsustainable industrial feedstock with one which is not only sustainable, but addresses some very serious environmental and socio-economic issues.
It is important to understand that neither Cannabis nor any other energy crop should become the only resource used on a global level for biofuels. Assisting to repeated large monoculture fields of Cannabis for biofuel production would be detrimental even for this highly adaptable plant.
A balanced mix between Cannabis and other crops may provide a solution, and it would be very short-sighted for society and industry to keep neglecting the Cannabis’ energy potential.
Cannabis is an environmentally friendly biodegradable alternative to both petrofuels and petroplastic and it will become more popular only when industrial mandates begin to favour environmental concerns for real.
An increased green consciousness between the general public followed by a bigger demand for natural products may be fundamental in triggering this process.
Here at Nature Going Smart we try to make people move towards a more nature-consciuos world.
Today we explained why Cannabis has the potential to be a real solution for a sustainable worldwide biofuel production.
All the rest is politics.
Deepen your knowledge on the biofuel topic checkin gout our articles “Solutions for biofuel: algae, non-edible oils & waste cooking oils“, “What is biodiesel” and “Drawbacks of modern production of biodiesel“.
