This is the expression I found in several references, including the English version of "Resolução ANEEL no. 266/98". Some examples, from Brazil and abroad:

Net Energy
... of net energy analysis does not depend on its normative value in the sense
... By not discounting energy costs and benefits, some net energy analysts ...
www.oilanalytics.org/neten/neten.html

[PDF] Recommendation of Aggregated Data Reporting under the EC- Act
File Format: PDF/Adobe Acrobat - View as HTML
The right Y-Axis displays the energy costs in Rs per unit output mix. ...
consumption costs in tariff orders only accepted based on this normative value. ...
www.energymanagertraining.com/announcements/issue19/DataRec...

[PDF] March 28 , 2002
File Format: PDF/Adobe Acrobat - View as HTML
The cost of generation of this energy is very low, in comparison ... distributed costs among consumers. 14. Changes in the Normative Value (VN) ...
www4.bcb.gov.br/Pec/Gci/Ingl/Focus/ I20020328-33%20Measures%20for%20Revitalization%20of%20the%20Electricit...

To know more about "Resolução 266/98", visit this site:

Histórico do Dia 14/08/98 - União Seção I
... Resolução 266 ANEEL. Estabelece limite para o repasse, para as tarifas de fornecimento dos preços livremente negociados na aquisição de energia elétrica ...
www.dado.com.br/diarios/dou/1998/08/u1980814.htm