The proposal of AEGPL aims to introduce modifications to bi-fuel vehicle definitions in order to permit the simultaneous use of gas and petrol in the gas mode:

• • To avoid over-use of petrol, provisions are provided to limit its use in duration (60 seconds maximum in starting-up) and/or amount (minimum limit to gas energy ratio);
• • A calculation method for gas energy ratio is provided basing on the conservative assumption that only gas is burned during the driving cycle (see GFV-16-02 for technical details); this assumption is in line with the present requirements for fuel consumption (FC) as well as for pollutant emissions, even if a certain use of petrol is already allowed (max 60 seconds over the cycle);
• • As for pollutants, no adaptation of correction factors are needed just in force of the conservative hypothesis that the test cycle is driven only on gas; the errors committed are also negligible (see GFV-16-02 for technical details).

TNO believes that the combined application of a maximum timeframe for starting-up the engine and a minimum limit to the gas energy ratio over the cycle is clearer and more stringent, closing the loopholes that the present regulations offers when setting only a time limit.

During the discussion it is highlighted that, according to the proposals, the requirement on the gas energy ratio would be applied to all the system types, so even to those that do notneed to use petrol beyond the start-up phase: the addition of a safeclause derogating such systems is evaluated;

With regard to the involvement of NG vehicles in the proposed adaptation of the two regulations, it is noted that also NG bi-fuel vehicles – factory built or retrofit – basically equipped with a direct injection petrol engine requires the use of a gas system capable to keep the petrol injectors cool, as with the LPG systems. The result can be achieved either by NG direct injection with the same petrol injectors (LNG direct injection is under development) or managing a limited use of petrol in the gas mode under certain circumstances, i.e. the solution in question;

Question for GFV: Do we have a positive feeling about the proposal to make it an informal document for the next GRPE or as a second option, to make it a formal document for the GRPE in June.

After discussion about the procedural aspects of introducing this new approach advocated by AEGPL and having been considered in-depth by the GFV, it is decided that the document will be presented as a GFV informal document in the next GRPE. It is intended, therefore, to involve more input from others not participating in the GFV directly and attempt to explain the new approaches to achieve support for it. The informal document should be provided to the GFV in the next weeks for final approval; Mr. Rijnders will send it to the GRPE secretariat to submit to the GRPE January meeting.