B100 Specifications
15. Annex 1 contains the recommended B100 specifications. These specifications will allow for good quality biodiesel to be produced from a number of feedstocks including tallow, soybean, rapeseed, palm, coconut and used cooking oil.
16. The specifications will apply to all biodiesel as a final fuel and as a blending component with petroleum diesel, for use in diesel engines, for automotive and non-automotive purposes. The scope of the specifications being for automotive and non-automotive purposes is a cautious approach given that non-automotive applications are often less sensitive to fuel quality. However this is considered appropriate, particularly while the industry is in its infancy and public confidence and awareness is low. All biodiesel should be able to meet the specifications proposed for B100 if the production process has been undertaken properly.
17. Parameters which are particularly important, or where views strongly diverge are discussed in more detail below.
Oxidation Stability
18. Oxidation of biodiesel produces organic acids which can corrode fuel system components. EN14214 has a limit of 6 hours induction period2 (IP) minimum for oxidation stability. Many jurisdictions follow EN14214 for this parameter including Australia, South Korea, Thailand, Brazil, and Malaysia. The United States Biodiesel Standard was recently amended from 6 hours to 3 hours minimum IP.
19. The Japanese motor industry is particularly concerned about the impact that the oxidation of biodiesel blends has on the corrosion of fuel system components. A test programme undertaken by the Ministry of Economy, Trade and Industry (METI) in Japan showed that even when B100 meets an oxidation stability of 6 hours IP, the resultant B5 blend can cause corrosion. The outcome of the test programme was a recommendation that B100 should have a minimum of 10 hours IP.
20. It is recommended that the New Zealand specifications require a minimum 10 hours IP for biodiesel blended with petroleum diesel for retail sale. Fuel stability is a very important parameter and to build and maintain consumer confidence it is prudent to be stringent until more is known about biodiesel's characteristics and its effects on vehicles. The majority of submitters support a minimum of 10 hours IP. It should be noted, however, that this support is generally due to the stance of the Japanese Automobile Manufacturers Association (JAMA) on oxidation stability, rather than New Zealand based research or empirical evidence. This requirement should have minimal cost implications, even for those feedstocks with naturally poor oxidation properties (e.g. rapeseed).
21. For B100 as a final fuel and as a blending component with petroleum diesel for non-retail sale, the recommended minimum IP is 6 hours. This reflects that the nature of the retail market requires more rigorous fuel quality regulations than when fuel is being sold via a written contract or supply agreement.
Iodine Value, Cetane Number, and Viscosity
22. Several other divergences from EN14214 are recommended to give added flexibility in sourcing good quality biodiesel for the New Zealand market from a number of different feedstocks. These are as follows:
- Maximum iodine value be set at 140g iodine/100g rather than 120g iodine/100g (the limit in NZS 7500 and EN14214);
- Minimum cetane number3 be 47 for biodiesel when used as a blending component with petroleum diesel, rather than 51 (the limit in NZS 7500 and EN14214). All end products (e.g. diesel/biodiesel blends) will continue to have to meet a minimum cetane number of 51; and
- Viscosity range is 2.0 – 5.0 mm²/s for biodiesel as a final fuel, and 2.0 – 6.0 mm²/s for biodiesel when used as a blending component with petroleum diesel. The requirements in the NZS 7500 and EN14214 is 2.0 – 6.0 mm²/s and 3.5 – 5.0 mm²/s respectively.
23. The iodine value, cetane number and viscosity are vehicle operability parameters that, in biodiesel, are directly related to the feedstock. EN14214 was developed based on rapeseed oil, which has a naturally lower iodine value and higher cetane number than soybean or sunflower based biodiesel. Biodiesel from these feedstocks are unable to meet EN14214 because of the limits required for iodine value and cetane number. Biodiesel from coconut oil and some used cooking oil is unable to meet EN14214 because of the limits required for viscosity.
24. It is considered appropriate that the specifications are feedstock independent and performance-based, and there are valid technical reasons for relaxing the iodine value, cetane number and viscosity requirements in comparison to EN14214. This approach is consistent with New Zealand's obligations under the World Trade Organisation rules which require New Zealand to not discriminate between ‘like products' that are sourced from different countries, or between 'like products' that are domestically produced and those that are imported.
25. Relaxing the viscosity limits is supported by the majority of submitters. Likewise for iodine value and cetane number with the notable exception of some of the (existing or planned) domestic biodiesel manufacturers. These manufacturers have indicated a strong preference for aligning with EN14214, which would effectively exclude some sources of imported biodiesel, including soybean based biodiesel from the United States, large amounts of which are currently exported due to subsidies provided there (which is known as the "B99" trade).
26. Any divergences from EN14214 are also not supported by those submitters representing the European vehicle manufacturing companies. Many warranties for European vehicles specify that any biodiesel component in the fuel must meet EN14214 and be made from rapeseed oil. The reason for this is unclear. The divergences proposed should not make a material difference to vehicle operability, and it is not practical to limit biodiesel in New Zealand to one feedstock. It should be noted that large volumes of soybean based biodiesel that does not comply with EN14214 are currently being imported and sold in Europe.
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