Renewable　energy　has　been　rapidly　developing　because　of　the　increasing　severity　of　pollution　and　energy　crises.　In　particular,　solar　thermal　power　generation　technology　has　been　attracting　considerable　attention　globally　due　to　its　large　scale,　low　unit　cost,　and　environment-friendliness.　Thus,　it　has　been　quickly　progressing.　The　intermittence　and　instability　of　solar　energy　can　be　solved　by　combination　of　solar　thermal　power　with　heat　storage　technology.　Mixed　molten　salts　stand　out　as　heat　transfer　and　storage　materials　due　to　their　wide　temperature　range,　low　vapor　pressure,　high　heat　capacity,　low　viscosity,　and　economical　environmental　protection.　In　the　present　study,　a　new　kind　of　quaternary　nitrate　molten　salt　was　presented.　The　salt　was　Hitec　salt　with　Ca(NO3)(2)　additive　and　has　a　low　melting　point,　high　decomposition　point,　and　low　cost.　The　thermo-physical　properties　of　the　proposed　salt,　such　as　melting　point,　decomposition　point,　crystallization　point,　specific　heat,　density,　thermal　conductivity,　and　thermal　stability,　were　measured.　Results　showed　that　the　melting,　crystallization,　and　decomposition　points　of　the　Hitec　salt　with　Ca(NO3)(2)　additive　were　83.1　degrees　C,　163.1　degrees　C,　and　628.5　degrees　C,　respectively.　The　proper　working　temperature　range　of　the　new　salt　was　200-565　degrees　C,　which　was　wider　than　those　of　Hitec　salt　(200-450　degrees　C)　and　solar　salt　(290-565　degrees　C).　The　average　specific　heat　and　thermal　conductivity　of　the　Hitec　salt　with　Ca(NO3)(2)　additive　were　approximately　1.52　J/(g　K)　and　0.655　W/(m　K),　respectively,　which　showed　better　heat　storage　and　heat　transfer　performance　than　did　Hitec　salt　(1.40　J/(g　K)　specific　heat,　0.350　W/(m　K)　thermal　conductivity)　and　solar　salt　(1.50　J/(g　K)　specific　heat,　0.520　W/(m　K)　thermal　conductivity).　An　experimental　study　was　conducted　on　the　stability　of　mixed　molten　salts　at　565　degrees　C　for　1200　h　and　120　times　for　quenching/heating　at　200-500　degrees　C,　and　the　Hitec　salt　with　Ca(NO3)(2)　additive　exhibited　good　thermal　stability.