SIVAEL is a simulation program for a power system with related CHP areas developed by the Danish TSO [1]. There is one external version of SIVAEL which is freely available. Currently there are four users of the software and it takes 1 to 2 weeks of training to complete a typical application.

SIVAEL makes a simulation with start/stop and load distribution on an hourly basis. The simulation period is from one day to one year. The program can handle condensing plants, CHP plants – both back pressure and extraction, but also wind power, electricity storage (batteries) and trade with foreign countries. In SIVAEL wind forecast errors can be simulated using a stochastic process to replicate real-life. Therefore, the model can simulate the need for upward and downward regulation in the day of operation as a consequence of unreliable wind forecast. The model however does not simulate heating demands outside of district-heating networks or the transport sector. The time control of the program is a true calendar, and all data apply from a certain time. It is thus possible to change data, in principle from hour to hour. It is possible to put a shadow price on different data, for example emissions. The thermal power plants have up to 3 fuel types with information on maximum percentage for each type. The program chooses the most economical fuel combination considering shadow prices for emissions. The output is a standard report for the whole simulation period and a possibility to choose a number of different data down to an hourly level.

A full list of publications involving SIVAEL can be found at [1]. Previously SIVAEL has been used to analyse the impacts of CHP and large-scale wind energy on the Danish energy-system [2], to examine the environmental impacts of Danish electricity and CHP generation [3], and also to project the consumption of natural gas in Denmark [4].


  1. SIVAEL,, 27th April 2009,SIVAEL,, 11th July 2009,
  2. Rapport fra arbejdsgruppen om kraftvarme- og VE-elektricitet (Report from the working group on electricity from cogeneration and renewable energy),, 2001,
  3. Environmental Report 2008,, 2008,
  4. Plan for security of natural gas supply,, 2007,