**6. References**


Taking into account before mentioned analysis, the calculations were performed to demonstrate the influence of 300 – 1 200 MW RES connection on transmission system. These calculations were accomplished for three scenarios with different spectrum of sources.

Scenario A – year 2010. From the point of view of DLD covering by own sources some power shortages occurs, mainly for combinations at higher absolute minimums, i. e. 2 400 MW and 2 600 MW and for lower power supply from RES. DLD is fully covered for higher values of power supply from RES. The situation is different from the point of view of auxiliary services covering. Possible operation of RES is restricted to 60 – 120 MW at higher system loads, when auxiliary services are reserved mainly for the outages of traditional

Scenario B – year 2011. In this scenario a new source has been put in operation – combined cycle Malzenice, which provides power for DLD coverage and also a good deal of auxiliary services. The situation from the point of view of auxiliary services covering is partially improved. Theoretically, secure operation of RES is possible with

Scenario C – year 2013. In this scenario, due to large additional installed capacity in the new sources, SPS will be fully self-sustaining in DLD covering and installed RES capacity can theoretically reach values up to 1 000 MW for any system load. Accomplished calculations have shown that any DLD can be covered and there are no problems with auxiliary services, but substantial problems will rise in electricity export. Specified technological limits for electricity export across border profiles can be found in SEPS web pages www.sepsas.sk. Maximum possible electricity export from Slovak transmission system is 2 000 MW. If this number is taking in account, i. e. considering maximum export of 2 000 MW, electricity production will be higher then allowed export in 90 % of

From the figures showing yearly costs for instantaneous availability of auxiliary services follows, that electricity price for end-consumers will depend on installed RES capacity, if

[1] SEPS, a.s.: *Technical Rules Establishing Technical Design and Operational Requirements for* 

[2] SEPS, a.s.: *Operating Instructions of the Transmission System Operator SEPS*, a.s., July 2011,

[4] SK Act No. 309/2009 Coll. *on the Promotion of Renewable Energy Sources and High-*

[5] SK Act No. 276/2001 Coll. *on Regulation in Network Industries and on Amendments and* 

*Connection to the Transmission System of the Operator SEPS*, a.s.,

actual electricity purchase prices and auxiliary services prices are valid.

[3] SK Act No. 656/2004 Coll. *on Energy and Consequential Amendments,*

*Efficiency Cogeneration and on Amendments to Certain Acts*

[6] SK Government Decree No. 317/2007 Coll. *on the Regulation of the Electricity*

http://www.sepsas.sk, July 2009

http://www.sepsas.sk

*Additions to Some Acts*

**5. Results of analyses** 

sources (non RES).

calculated cases.

**6. References** 

powers of 250 – 300 MW.

Results can be briefly summarized as follows:

