Methods for increasing efficiency of Parabolic Troughs’ (PT) Heat Collecting Elements (HCE) mainly suggested in ENIN are considered. PT are the elements of Solar Power Plants (SPP) with different assignments. The methods include the application of water and liquid heat carrier with dye (nanoliquid). It is suggested to use this nanoloquid in two-loop power plant. Such nanoliquid provides intensive absorption of solar energy in HCE volume. The results of tests for determining the spectral and thermal stability of such solutions are quite satisfactory. The calculations showed that the efficiency of SPP with such solutions is quite high.