Scarcity of fresh water and depletion of primary energy have become great issues worldwide. Thus application of renewable energy sources for desalination has become the subjects of great interests. This paper presents a novel thermal desalination method: a spray-assisted low-temperature desalination technology powered by solar energy. The spray desalination technology applies direct contact heat transfer mechanism in the evaporation process, which differs from traditional methods that rely on metallic surfaces. Direct solar coupling of solar thermal collector has been considered due to the quick response of the system to heat source temperature. A lumped parameter model is developed for the spray desalination system. The model is based on the heat and mass balances within each system component. The long-term performance of the desalination system powered by solar energy under the climatic conditions of Singapore is evaluated in terms of distillate water production and energy efficiency. The annual average production rate is 9.66 kg/day for a solar collector of 2 m², with a seawater flowrate of 1.2 LPM and a cooling water flowrate of 0.4 LPM. The annual solar efficiency is 72.4%.