Abstract: To avoid heat flux variations and non-uniform vapor-liquid distribution in parabolic collectors, the volume expanding evaporative solar steam generation system is proposed. Using actual solar radiation data from NASA SSE6.0 database, a 600 MW coal-fired power plant hybrid with a volume expanding evaporative steam generation system was established. Turbine stages at off-design condition were calculated with DNI data over a one-year period. And the daily, monthly and yearly thermodynamic performance of the hybrid system in Lhasa area was analyzed respectively. The results exhibit the same trends in steam mass flow, daily power generation and DNI with the monthly power generation reaching the maximum in June (2.95×10⁸ kW·h of electric energy produced), while the solar collector efficiency shows the opposite tendency. Moreover, the cycle thermal efficiency of power generation is relatively higher in summer, which typically ranges from 32% to 35% throughout the whole year. Annual solar thermal efficiency is approximately 22.5% by average. The results may provide a novel direction toward the application of solar energy system hybrid with coal-fired power generation.