Coconut oil takes off as a biofuel in the Pacific

Posted: 21 November 2005

Author: Jeremy Hamand

Almost unnoticed, coconut oil is taking off among the Pacific islands as an alternative to imported, costly and polluting, diesel oil. Jeremy Hamand reports here on the spread of this latest biofuel, drawing in part on internet exchanges among islanders linked to the Small Islands Voice website.

“We live on islands where the most noticeable product is coconuts, but until recently almost no vehicles here used coconut fuel,” says Giff Johnson of the Marshall Islands. Things have changed dramatically in the last year or so, he explains. “Tobolar Copra Processing Plant’s vehicles have now started using coconut oil as a substitute for diesel fuel, and Pacific International Inc. has moved its entire fleet of heavy equipment vehicles and its many ocean-going vessels to the cheaper and cleaner coconut oil fuel.”

Coconut biofuel
Coconut oil can be blended with diesel to produce a cleaner biofuel.
Coconut oil can be blended with diesel to produce a cleaner biofuel. Credit: Tony Deamer

It makes economic sense: in the Marshall Islands, coconut oil sells at about US$2 a gallon – compared to the price of diesel, which has hit US$3.50 a gallon at local gas stations following the recent oil price increases.

Cleaner and cheaper

The same considerations apply in other Pacific islands, where there are great opportunities to use coconut oil as a fuel, according to Jan Cloin of the South Pacific Applied Geoscience Commission. “Coconut oil can be blended with diesel fuel, and under certain conditions totally replace it. Coconut oil in Pacific islands countries is increasingly used in both transport and electricity generation through its lower local cost. Other benefits include the support to local agro-industries and a decrease in emissions.”

In Fiji, the Electricity Authority are testing a larger 3.3Mw Cat engine running on coconut oil at their Sigatoka power station and are looking at that and other fuels from biological materials such as crops, animal wastes as an alternative to diesel. With diesel at over $900/tonne, biofuels at up to $700 are a workable replacement. On a recent survey to one of the remotest Fiji islands, Rotuma, it was observed that the island had the potential to use the coconuts lying around to displace almost entirely the need to import diesel, as the production available locally was estimated at about 2,000 tonnes per year of copra, which would produce around 1,600 tonnes of coconut oil, and if refined into biodiesel would produce around 1,500 tonnes.

In Samoa, too, the Electric Power Corporation is currently running a trial using 15 per cent locally produced coconut oil mixed with 85 per cent diesel in some power generators. So far, they have had good results, and, with the present diesel prices, at lower cost.

A coconut oil/diesel fuel blend currently being used in Vanuatu initially mixes 20 parts coconut oil with one part kerosene. This blend is then mixed 2:1 with diesel to give an effective 64 per cent coconut oil biofuel.

Suitability

Rudolph Diesel himself believed that the use of biomass fuel was the real future of his engine. At the World Exhibition in Paris in 1900 where he demonstrated his engine, Diesel said: “The diesel engine can be fed with vegetable oils and would help considerably in the development of agriculture of the countries that use it.” In fact, his compression ignited engines were powered by a biomass fuel, vegetable oil, until the 1920s when petroleum diesel was introduced.

During the Second World War the armies fighting in the Philippines used coconut oil to run diesel engines. Since then many further experiments and trials have been successfully run using coconut oil as a direct substitute for diesel. Bougainville Island in Papua New Guinea had diesel generators and trucks run on locally produced coconut oil during a trade blockade.

But there are potential problems in using coconut or other vegetable oils in unmodified diesel engines. Coconut oil has up to 30 times higher viscosity than regular diesel at the same temperature, and solidifies below temperatures of 25°C, so most engine modifications include a fuel heater. As heat is exchanged between the engine coolant and the fuel, the oil viscosity approximates that of diesel.

Using pure coconut oil in standard engines is very attractive through its low cost, but it requires special technical supervision and may shorten engine life. Research suggests that engine durability is compromised when fuel blends contain more than 20% vegetable oil. Deposits on the pistons, valves, combustion chambers and injectors can cause severe loss of output power and engine lubricant deterioration. Extra refining can reduce these drawbacks.

Most adaptations incorporate a start and stop on regular diesel. As soon as the engine is operating at rated temperature, the fuel supply switches to coconut oil and just before shutting down, the supply is switched back to diesel. This system ensures that the fuel system has diesel ready for a cold start.

Sustainability

The use of coconut oil to replace diesel has a range of potential environmental benefits. First, there is the decrease of emissions of poisonous gases and particulate matter as compared to diesel, through the higher oxygen content of coconut oil, although these benefits are not so evident when using straight vegetable oil in standard engines. Secondly, the use of coconut oil can be considered CO2 neutral. The CO2 stored in the coconuts, husks and shells are used in the process of oil production (husk and shells for drying the copra) and burning of the oil. This CO2 is again sequestrated during the growing of new trees and nuts.

Other advantages of coconut oil include:

  • Lower emissions and toxic fumes than petroleum diesel fuel
  • Smoother running and reduced engine knock
  • Availability to the producer in remote areas to run machinery and generate electricity when the roads are cut off in the wet or prices are too high
  • The oil is a sustainable resource.
What is more, supporting a local industry which cuts down on fuel imports will benefit fragile Pacific island countries substantially through improvements in balance of payments and job creation. Simultaneously, coconut farmers are given access to a new, potentially booming market as the difference between the cost of their product and the benchmark of the diesel price further widens.

Even though there is considerable evidence of the environmental benefits of using coconut oil as a fuel, it is the local cost of petroleum fuel that is the real driver behind these developments in the Pacific island economies. Electric utilities generally suffer from great dependence on imported diesel for power generation and are seeking new ways to hedge these risks.

Tony Deamer of Vanuatu has the last word: “Give coconut oil a go. It is here now, it will run in your big 4x4 macho machine too and your present generator sets, so no big capital investment is needed. Just start making more good quality oil. Education is the key, not capital – we have all we require now in most places. Fiji, Samoa, Vanuatu, Kiribati all have oil mills and small ones are popping up in the Solomons too. So give it a go!”