Hourly-seasonal tarrifs in Brazil

One of the main initiatives for demand side management in Brazil is implementation of hourly-seasonal tariffs (HST) since the 80s for the consumer units connected to the National Interconnected System (SIN).
With introduction of HST, loads subject to this economic sign started to modulate according to their sensitivity to the tariff. As the consumption tariff and demand for power becomes more expensive at peak hours, after customers analyze the cost-benefit ratio, they assess which loads can be shut down, in order to optimize their production cost.

The experiment conducted achieved a reduction of about 12.5% in charging electric systems in Brazil, increasing their reliability, improving conformity of the voltage levels and postponing investments for expansion initially identified as needed.

This arrangement brings advantages to the loads, since it increases the feeder productivity, and resulting in cost reductions in distribution systems over the long term. On the other hand, the quality increase in the service rendered by the company is instantly passed on to consumers, since both shutdowns and voltage level oscillations are minimized.

The establishment of electric energy tariffs that optimize transmission capacity and also reflect the elasticity of the consumer units in the calculation process contributes to the efficient use of available generation capacity.

Consideration of the load elasticity in the calculation process allows for the establishment of restrictions on tariffs to be defined so as to maintain tariffs within the payment capacity of the consumer units which start feeling the need to use electric energy more rationally. As such, the tariff ceases to be a commercial fraud inducing factor and effectively becomes a means to promote load management.