BEFORE OPAL FUEL The logistics of operating a remote fishing lodge in the middle of Arnhemland have been considerable. Everything has to be barged in or, if it’s urgent and important, it is flown in. Prior to 2006, the Arnhemland Barramundi Nature Lodge barged 200L drums of unleaded fuel to Maningrida. With up to seven boats on the water at any one time, fuel consumption could be as high as 3500L each week, so can you imagine the resources and man hours that were required to deal with that amount of fuel going through the boats, particularly for a small operation? For starters, quantities required had to be worked out in advance and ordered to be delivered to the barge company in Darwin in time to be shipped to Maningrida, a sea distance of more than 600km. Upon arrival, drums would be loaded on a Toyota trayback and big, dual-axle trailer, and carted 20km on gravel roads to the Lodge. Once there, they would be offloaded and rolled into a large shipping container, stood up and locked safely away. Getting the fuel to the boats was another ongoing logistical exercise: each morning the fishing guides would pump their daily requirement of unleaded petrol into 20L jerrycans, cart those back to the Lodge boat compound in Maningrida and funnel the fuel into the boat tanks. Of course, the reason for all this handling and security was to ensure the unleaded petrol could not be accessed by young people in the community and used for the incredibly-harmful practice of petrol sniffing. And then along came Opal fuel! What a relief it was to be able to fuel the Lodge boats right at the bowsers in Maningrida. With the arrival of Opal fuel, petrol sniffing was no longer an issue for the community, and it saved the Lodge a lot of time, effort and wear and tear on equipment. OPAL…THE OLD AND THE NEW With high-performance outboard engines like those at the Lodge, the use of fuel additives with the first Opal fuel formula enhanced the performance of these engines. However, in 2010 the Lodge was involved in field testing of the new and improved Opal. The field tests demonstrated clearly that the new and improved Opal fuel was safe to use without the need of an additional additive. In addition, outboard engine testing at an independent Orbital WA laboratory showed that, after running new and improved Opal fuel for five hours per day over three consecutive days, there was no significant change seen in the condition of the inlet ports, valves, fuel injectors or spark plugs nor a significant reduction in flow rate which would indicate fouling. Independent testing on Opal fuel confirmed that it offers equivalent performance to regular unleaded 91. In fact, the engine stability at the 2200-2500rpm mode of operation appeared to improve whilst using new and improved Opal fuel. For the last two years, the Lodge has used this improved version of Opal fuel, without additives and without any fuel issues, and the outboards have continued to run smoothly whether trolling ultra-slow for barramundi or travelling at speed between spots. OPAL FUEL STORAGE As with unleaded 91 petrol, Opal fuel should be stored in 2.5L or 5.0L steel cans or in 25L jerry cans. Plastic containers of the approved type, with the Australian Standards mark (AS2906-1991) on the bottom, can also be used. Note that the storage of fuel in any quantity is hazardous and this advice does not include safety and legislative guidelines for fuel storage. For details on these safety and legislative guidelines for fuel storage, please refer to the Australian Standard AS1940. As with all petrols, when Opal fuel is kept in an open container where it is exposed to the air, it will – in time – completely evaporate. As it evaporates, the composition and properties will change because different components evaporate at different rates. This is a normal feature of petrol and helps describe the process which takes place when it is stored in equipment fuel tanks. Petrol in sealed containers The storage life of petrol is one year when stored under shelter, in a sealed container. Once a seal is broken, the fuel has a storage life of six months at 20°C or three months at 30°C. Petrol in boat tanks The storage life of petrol in boat fuel tanks is one month. This can be extended by topping up with one third of fresh fuel, which restores the volatile components that have evaporated. Topping up with fresh fuel will help; however, it is not a foolproof strategy for engines that are used only intermittently. It’s also a good idea to keep your tank half full to stop water vapour from being sucked in and condensing. USING OPAL FUEL As Opal fuel is equivalent to regular unleaded fuel (with an octane rating of 91), it can be mixed with the regular unleaded 91 fuel already in your vehicle or boat fuel tanks. There is no need to adjust your vehicle or outboard management system to use Opal fuel. And if you have a two-stroke engine, Opal fuel can be mixed with two-stroke fuel where the manufacturer recommends the use of regular unleaded 91. Furthermore, Opal fuel is subsidised under the Australian Government’s Petrol Sniffing Prevention Program. This allows Opal fuel to be priced at an equivalent local rate to regular unleaded 91, so there is no need to budget extra for travels around Australia. THE BOTTOM LINE Opal fuel has been available in some parts of the Northern Territory, South Australia and Western Australia since 2005. It was introduced in Kakadu National Park in 2011 and has been used by the competitors in the Aurora Kakadu Klash for the past two years. Australian Government research shows that the introduction of Opal fuel has helped reduce the incidence of petrol sniffing by up to 94% in affected communities, and thus has been a major success.