29th Symposium on Fusion Technology (SOFT 2016)

O1B.1 Uncertainties in power plant design point evaluations

5 Sep 2016, 16:40

20m

Meeting Hall I 1st floor (Prague Congress Centre)

Board: 1

Oral A. Experimental Fusion Devices and Supporting Facilities O1B

Speaker

Hanni Lux (CCFE)

Description

When designing a new large experimental device, extrapolation from current knowledge and rules into unexplored design space is unavoidable, and predicting the behaviour of a new device is therefore subject to significant uncertainties. This makes it difficult to determine an optimal design. For conceptual fusion power plants, a further concern is the large possible variation in expected plasma performance in fusion devices beyond the currently probed range. In particular, extrapolating scaling laws like for the L-H threshold or the confinement time hold large uncertainties as far as the predicted physics are concerned. On the technology side, predictions for the efficiency of the heating and current drive system or the allowable stresses on the magnet systems are still variable and can potentially influence the optimal machine design. In this work, we evaluate the effects of both physical and technological uncertainties in the current European pulsed DEMO designs (nominally 500MW net electrical power, 2 hour pulse length). We use a Monte-Carlo method in combination with the systems modelling code PROCESS to map out the probable machine performance. The results show the likelihood of current designs fulfilling the high-level goals of providing several hundred MW of net electricity while maintaining a reasonable pulse length, and we give recommendations of how to effectively minimise existing design uncertainties.