US firm Perihelion to use peanuts for biodiesel

In an interesting development, Alabama based firm Perihelion Global held its groundbreaking ceremony for its biodiesel plant which aims to produce 40 million gallons (151 million liters) of biofuel per year using peanuts as a feedstock. The company plans to be the third largest green fuel refinery in North America and the largest using the nuts as its feedstock. If the company succeeds in producing competitive biofuels, it will become a reference case for developing countries that have a large groundnut growing potential.

Peanuts or groundnuts (Arachis hypogaea L.), a nitrogen-fixing legume, are cultivated in over 100 countries in the global south (overview at the International Crops Research Institute for the Semi-Arid Tropics). It is the 13th most important food crop of the world. Today, groundnut is the world's 4th most important source of edible oil and the 3rd most important source of vegetable protein. Groundnut seeds contain high quality oil (50%), easily digestible protein (25%) and carbohydrates (20%).

The nut is currently grown on 26.4 million ha worldwide with a total production of 36.1 million metric tons, and an average productivity of 1.4 metric tons per hectare. Major groundnut producers in the world are: China, India, Nigeria, USA, Indonesia and Sudan. Developing countries account for 96% of the global groundnut area and 92% of the global production.

Let us have a quick overview of countries in the Sahel - the poorest countries on the planet - and how much land is suitable for sustainable groundnut production, to get a rough idea of the technical biofuels potential. As a quick reference, we indicate the country's ranking on the 2006 Human Development Index, to indicate its development status (we assume that large-scale biofuel production has the potential to fuel social and economic development).

Using the International Institute for Applied Systems Analysis's GAEZ database on land suitability for rainfed groundnut, the situation looks as follows:
biomass :: bioenergy :: biofuels :: energy :: sustainability :: peanuts :: groundnut :: biodiesel :: Sahel ::

The data assume high inputs, no irrigation, and a maximized technology mix.

Let us take the United States as a reference case:

:: United States: 23.8 million hectares of 'very suitable' to 'moderately suitable' land, with an average yield of 1.57 tons/ha. HDI ranking (2006): 8.

The countries of the Sahel:

:: Benin: 9.2 million hectares of 'very suitable' to 'moderately suitable' land, with an average yield of 2.7 tons/ha. HDI ranking (2006): 163.
:: Burkina Faso: 14.6 million hectares of 'very suitable' to 'moderately suitable' land, with an average yield of 2 tons/ha. HDI ranking (2006): 174.
:: Chad: 24.6 million hectares of 'very suitable' to 'moderately suitable' land, with an average yield of 2.1 tons/ha. HDI ranking (2006): 171.
:: Central African Republic: 28.2 million hectares of 'very suitable' to 'moderately suitable' land, with an average yield of 2 tons/ha. HDI ranking (2006): 172.
:: Mali: 17.5 million hectares of 'very suitable' to 'moderately suitable' land, with an average yield of 1.8 tons/ha. HDI ranking (2006): 175.
:: Niger: 2.8 million hectares of 'very suitable' to 'moderately suitable' land, with an average yield of 1 tons/ha. HDI ranking (2006): 177 (last).
:: Senegal: 7.1 million hectares of 'very suitable' to 'moderately suitable' land, with an average yield of 1.7 tons/ha. HDI ranking (2006): 156.
:: Sudan: 65.2 million hectares of 'very suitable' to 'moderately suitable' land, with an average yield of 2.1 tons/ha. HDI ranking (2006): 141.

Other countries in Africa with a large land base suitable for groundnut production are Mozambique (45 million ha), Tanzania (38 million ha), Zambia (47 million ha) and Angola (48 million ha). This quick overview shows that there is considerable production potential, but doubts remain on the feasibility of using groundnuts for biodiesel production. Currently, groundnut oil is the most expensive of all globally traded vegetable oils.

However, groundnuts have several advantages that, with increased investments, make them suitable for biodiesel production in the future:

Groundnut is an interesting energy crop for several reasons:

* it grows well in semi-arid regions and requires limited fertilizer and water inputs
* therefor it does not cause any pressures on rainforest ecologies, a critique often raised against other tropical energy crops (most notably palm oil)
* the regions where groundnut thrives are populated by the world's poorest people (especially Sahelian countries, like Mali, Niger, Mauritania, Chad, the Central African Republic, Sudan -- who all rank at the bottom of the scale of, for example, the Human Development Index)
* many non-commercial and non-edible varieties with high yields can be developed and improved
* In contrast to other energy crops which thrive well in semi-arid regions, such as the perennial shrubs jatropha curcas and pongamia pinnata, groundnut can be harvested mechanically

All of the crop's parts can be used as bioenergy feedstocks:

* the nuts themselves have a high oil content (around 50%) and one hectare of groundnut yields around 1000 litres of oil; the oil has a relatively low melting point, a medium iodine value and a high flash-point - characteristics which make it a suitable oil for biodiesel production
* the groundnut has a residue-to-product ratio of around 0.5-1.2 for pods and 2.2-2.9 for straw; this means that for every ton of nuts produced, 500 to 1200kg of shells become available and 2.2 to 2.9 tons of straw residue are harvested; in total groundnut yields between 3.7 and 5.1 tons of biomass per hectare
* these residues offer an interesting solid biofuel, with a relatively high energy content of 16Mj/kg for shells and 18Mj/kg for straw - with advanced bioconversion technologies (cellulosic ethanol or pyrolisis) this 'waste' biomass can be turned into liquid fuels and bioproducts; alternatively, it could be densified and used in biomass (co-firing) power plants


Back to Alabama. The Perihelion plant will employ approximately 150 people and will use peanuts grown by local and regional farmers to produce a projected 40 million gallons of bio-diesel annually from the facility. CEO John Beebe also announced that Perihelion had reached an agreement with local company, Crew Distributing, to distribute their biofuel.

Beebe said that at the projected capacity, the plant will provide the United States slightly more than one-tenth of one percent of the proposed mandatory fuel standard set by the president.

More information:

For the land suitability data, see the International Institute for Applied Systems Analysis and its dedicated website: Global Agro-ecological Assessment for Agriculture in the 21st century, made in collaboration with the FAO. At that website, click "spreadsheets" > "additional" and then select the crop in question.

The Human Development Index ranking for 2006 can be found here.

For an in-depth look into the economics of groundnut oil and its potential as a biodiesel feedstock, see: Biopact: The spirit of Rudolf Diesel: peanuts and socialism - Sept. 19, 2006.