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3 wonder plants for bioenergy

 By Livia Formisani

Touted by some as “green gold,” by others as liabilities, bioenergy crops are a polarizing subject. Due to the lower amounts of greenhouse gas they emit, biofuel, biogas and biomass are a great alternative to fossil fuels. Yet, they have been the object of several controversies…

The reason is simple: first-generation biofuels are made from sugar and oil, such as those extracted from corn, sugarcane and soybean, which impact food prices and availability. Over the past decade, though, researchers have turned their attention to the so-called second-generation biofuels and biomasses, based on cellulose from non-food crops and even thriving on degraded land.
Recently, research projects across the globe have been testing the feasibility of at least three “wonder plants” for bioenergy production, with very promising results.

1. Jatropha curcas (Africa)

Jatropha curcas (Barbados Nut) is a shrub native to Mexico growing in very dry environments and on wasteland. The oil extracted from its seeds can be used — as it is — as biofuel. Residual materials are employed to produce biogas or as fertilizers, and other parts of the plant are used in traditional medicine or for soap manufacture. As Jatropha is a non-food crop, growing even in the desert, it doesn’t compete with food production nor fosters the clearing of rainforests.
Mainly diffused in southern Africa and India, it has attracted consistent investments in the 2000s, when it has been hailed as the new green gold. When those projects, however, didn’t yield as expected (due to a number of reasons), the plant rapidly got a bad rap.
“Jatropha the plant did not fail, Jatropha the business model failed.” Kirk Haney, President and Chief Executive Officer of SG Biofuels
Recently, however, the Singaporean bioenergy firm JOil engineered new Jatropha hybrids with higher yielding power. Around the same time, scientists at Egypt’s National Research Center successfully produced aviation biofuel from Jatropha, while different business models are currently being explored to ensure sustainable farming conditions. The future might indeed hold many surprises for this crop.

Wonder plant n.1: Jatropha curcas (Ton Rulkens, Wikimedia)

2. Bamboo (Asia)

Resistant, flexible, quick: bamboo is a wonder plant in its own right, used massively across Asia for a variety of purposes, including scaffolding and rayon production. One might argue, however, that bamboo gives its best as a biomass: growing quickly, and tall, it allows for a much higher yield per acre than other crops. In fact, a variety of bamboo holds the Guinness World Record for “Fastest Growing Plant” with 35 inches (91 centimeters) per day, and other varieties can grow over 98 feet (30 meters) tall. One of its numerous advantages is also that it is harvested by cut, with the same stalks continuing to grow, thus not needing to be replanted.
What’s more, bamboo biomass has a higher heating value compared to other biomasses, including corn, as well as lower levels of moisture — characteristics which make it well-suited for usage in thermal power plants. But not only that: bamboo can also be used to produce biofuel, due to its lower ash content and alkali index, as well as biogas — making it a great all-rounder in the bioenergy world.
A real miracle plant, bamboo is also one of the best cultures to restore degraded land from activities such as mining or deforestation.

Wonder plant n.2: Bamboo

3. Arundo donax (Europe)

Arundo donax (Giant Cane/Giant Reed) is a type of cane native to the Mediterranean Basin, where it grows in damp grounds, along bodies of water and even in the presence of saline water. A very resilient weed, it has a robust root system preventing soil erosion, a quick growth rate (even in degraded soil), and canes reaching a height of 20-30 feet (6-9 meters).
Similarly to bamboo, Arundo donax is used for the production of biomass, biofuel and biogas. It grows tall and quick, thus offering a high yield per acre, with the added benefit that it is self-propagating, and therefore requires less work. For this exact reason, however, in the right climate the plant can become invasive, an aspect which has led several U.S. states to express concern over its cultivation for bioenergy. In Europe, however, where the crop is native, research projects have shown its viability.
Another interesting property of Arundo donax, which could potentially be combined with its bioenergy potential, is its capability to effectively treat wastewater and even improve soil quality in the areas where it is planted.
In each case, mass production is no longer a main goal. To minimize the impact on the environment and the society, scientists are now focusing on designing sustainable plantations. Some of the ways currently being explored are growing those species side-by-side with others (to protect local economies), privileging native species and planting on wasteland. Therefore, it may very well be that in the future, we will gather energy from all those plants, each sustainably growing in its own particular local setting.

Wonder plant n.3: Arundo donax

READ MORE: Computerized future by Benjamin Plackett

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about the author
Livia Formisani