As it is mandatory to fill in all the information boxes in EPREL, can 0.00 be used as a value ?

All the mandatory fields must be filled in. If it is a number, please check the allowed values in the Wiki (for each product group there is a table with all the fields and the allowed values): https://webgate.ec.europa.eu/fpfis/wikis/display/EPREL/EPREL+Exchange+model+parameters.

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