(Translated from original letter)

ARTABRA, S.A. E15080 ARTEIXO – La Coruña – (Spain)

15^th February 2001

Dear Sir,

We are pleased to certify the excellent results obtained from the use of “rb bertomeu” additive for fuel oil beco F1/ASF in our industrial facilities at Arteixo, and especially for adding the additive to the fuel oil which we use in the engines of our cogeneration [power] plant.

Our cogeneration [power] plant comprises two Deutz diesel engines, one type TBD 645 L9 and one type BV 16M 640, capable of producing 10 Mwe.

In January of 2000 we began using the additive, using our previous experience; and we can express that the periods of exhaust valve and turbocompresor maintenance (indicated by the manufacturer) have been increased, in the case of the Deutz TBD 645 L9, in 1,500 hours more, and in the case of the Deutz BV 16M 640, in 1,000 hours more (at the moment) without having to intervene either of these cases yet. That is to say, for example, that before, in a period of 3,000 hours 7 blown exhaust valves were replaced, with the use of beco F1/ASF we have so far reached 4,300 working hours without having to replace any exhaust valve.

Decrease of combustion residues in exhaust valves, nozzle rings and exhaust collectors.

In the case of the turbocompressors we have surpassed the lifespan of elements of the casing, which were previously substituted due to corrosion.

We can also mention that other elements which previously needed replacing before the periods indicated by the manufacturer, such as injection pumps and injectors, are being extended for the same number of hours previously quoted.

We authorise the use of this letter for reference purposes.



(Translated from original letter) ARTABRA, S.A. E15080 ARTEIXO – La Coruña – (Spain) 15^th February 2001 Dear Sir, We are pleased to certify the excellent results obtained from the use of “rb bertomeu” additive for fuel oil beco F1/ASF in our industrial facilities at Arteixo, and especially for adding the additive to the fuel oil which we use in the engines of our cogeneration [power] plant. Our cogeneration [power] plant comprises two Deutz diesel engines, one type TBD 645 L9 and one type BV 16M 640, capable of producing 10 Mwe. In January of 2000 we began using the additive, using our previous experience; and we can express that the periods of exhaust valve and turbocompresor maintenance (indicated by the manufacturer) have been increased, in the case of the Deutz TBD 645 L9, in 1,500 hours more, and in the case of the Deutz BV 16M 640, in 1,000 hours more (at the moment) without having to intervene either of these cases yet. That is to say, for example, that before, in a period of 3,000 hours 7 blown exhaust valves were replaced, with the use of beco F1/ASF we have so far reached 4,300 working hours without having to replace any exhaust valve. Decrease of combustion residues in exhaust valves, nozzle rings and exhaust collectors. In the case of the turbocompressors we have surpassed the lifespan of elements of the casing, which were previously substituted due to corrosion. We can also mention that other elements which previously needed replacing before the periods indicated by the manufacturer, such as injection pumps and injectors, are being extended for the same number of hours previously quoted. We authorise the use of this letter for reference purposes.