In accordance with the legislation in force, the following types of agents carry out activities at SEN (National Electricity System) :
Ordinary Regime Producers
Ordinary regime producers have conventional stations (hydro- and/or thermal, oil, coal and natural gas) and can sell the electricity produced through bilateral contracts with clients or with electricity traders or through participation in organised markets. Ordinary regime producers can also supply ancillary services, signing contracts with the system operator or participating in markets specially organised for this purpose.
Special Regime Producers
The production of electricity of special regime producers is considered as being an activity which is licensed under special legal regimes, in the scope of the adoption of policies aimed at encouraging the production of electricity, namely through the use of renewable endogenous resources or technologies that produce both heat and electricity.
Special regime producers have the right to sell the electricity they produce to the last resort supplier, under the conditions established by the specific legislation applicable.
Transmission Network Operator
The transmission network operator is a concessionary entity under a public regime from the National Transmission Network of Electrical Energy (RNT), with the following fundamental objectives:
a) Ensure the exploitation, maintenance, planning and construction of the RNT
b) Ensure non-discrimination between users;
Distribution Network Operators
The distribution network operators are concessionary entities under a public regime from the National Distribution Network (RND) or Low Voltage networks, with the following fundamental objectives:
a) Ensure the exploitation, maintenance, planning and construction of the RND or Low Voltage Networks
b) Ensure that there is no discrimination between users;
Last Resort Supplier
The last resort supplier is subject to the obligations of a universal service. The exercise of the activity of the last resort supplier is subject to the attribution of a license.
Electricity suppliers can contract the electricity needed to supply their clients signing bilateral contracts or through participation in other markets.
The commercial relationship with the clients comes from the signing of an electricity sale and purchase contract which must comply with the provisions established in the Commercial Relations Code.