Context. Thanks to their high quality, new and upcoming asteroseismic observations, with CoRoT, Kepler, and from the ground, benefit from experience gained with helioseismology. Aims. We focus, in this paper, on solar-like oscillations, for which the inclination of the rotation axis is unknown. We present a theoretical study of the errors of p-mode parameters determined by means of a maximum-likelihood estimator, and we also analyze correlations and biases. Methods. We used different, complementary approaches: we performed either semi-analytical computation of the Hessian matrix, fitting of single mean profiles, or Monte Carlo simulations. Results. First, we give analytical approximations for the errors of frequency, inclination and rotational splitting. The determination of the inclination is very challenging for the common case of slow rotators (like the Sun), making the determination of a reliable rotational splitting difficult. Moreover, due to the numerous correlations, biases -more or less significant -can appear in the determination of various parameters in the case of bad inclination fittings, especially when a locking at 90• occurs. We also discuss this issue. Nevertheless, the central frequency and some derived parameters, such as the total power of the mode, are free of such biases.

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A B S T R A C THydropower is the central pillar of the current Swiss electricity mix. The Swiss energy transition will profoundly change the electricity mix by transitioning a third of electricity generation from nuclear towards renewable energy sources mainly. This backbone role of hydropower is hindered by the current Europe-wide sluggish economic situation, characterized by subsidized new renewables energies which distort electricity prices, a partially liberalized market and power production overcapacity. In this difficult context, a strong and comprehensive political support through long-term policy will be of utmost importance to accompany hydropower across this transformation. This article explores various subsidy instruments, before using the general framework of "System Engineering" to base a precise recommendation for Swiss hydropower. The recommended mixture of investment contribution with discount reclamation appears the most appropriate instrument. Also, the short time horizon means that the subsidization can be quickly terminated if necessary. In parallel, it is a mature instrument since it is already used for other new renewable energies. The discount model allows reclaiming subsidies in case of an excess profitability. The strength of this study is its robust, comprehensive and allencompassing methodology which can be replicated to other cases (for instance, other technologies or energy sources) and other countries.

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