A modular panel for thermal energy transfer particularly configured for being used in ceilings and walls, comprising a heat-insulating layer forming a supporting structure demarcated by at least a lower face , an upper face , two side faces and two end faces , the panel further comprising at least one conducting plate attached to the lower face of the heat-insulating layer , wherein said conducting plate is formed by: • a groove embedded in the heat-insulating layer defining a longitudinal cavity which is configured to house a hydraulic pipe , said groove in turn being finished by two longitudinal edges which are flush with the lowerface , defining a longitudinal opening which is configured to allow inserting the hydraulic pipe ; and • a transfer plate prolonging from at least one of the longitudinal edges and extending on the lower face ; and closure means configured to seal the longitudinal opening and press the hydraulic pipe against the groove , characterized in that the closure means comprises: • a longitudinal embossment having a toothed profile arranged in each of the longitudinal edges of the groove of said conducting plate ; and • an elastic closure element configured to compensate for the expansions of the hydraulic pipe caused by temperature changes thereof, wherein said closure element is formed by: ∘ two longitudinal sides having a toothed profile fitting with the longitudinal embossments to allow securing the closure element to the conducting plate and sealing the longitudinal opening , assuring the leak-tightness of the longitudinal cavity ; ∘ a longitudinal seat which is configured to press the hydraulic pipe against the groove , assuring the thermal energy transfer between the hydraulic pipe and the conducting plate ; and ∘ a lower base which is flush with the lower face . • a groove embedded in the heat-insulating layer defining a longitudinal cavity which is configured to house a hydraulic pipe , said groove in turn being finished by two longitudinal edges which are flush with the lowerface , defining a longitudinal opening which is configured to allow inserting the hydraulic pipe ; and • a transfer plate prolonging from at least one of the longitudinal edges and extending on the lower face ; and closure means configured to seal the longitudinal opening and press the hydraulic pipe against the groove , characterized in that the closure means comprises: • a longitudinal embossment having a toothed profile arranged in each of the longitudinal edges of the groove of said conducting plate ; and • an elastic closure element configured to compensate for the expansions of the hydraulic pipe caused by temperature changes thereof, wherein said closure element is formed by: ∘ two longitudinal sides having a toothed profile fitting with the longitudinal embossments to allow securing the closure element to the conducting plate and sealing the longitudinal opening , assuring the leak-tightness of the longitudinal cavity ; ∘ a longitudinal seat which is configured to press the hydraulic pipe against the groove , assuring the thermal energy transfer between the hydraulic pipe and the conducting plate ; and ∘ a lower base which is flush with the lower face . ∘ two longitudinal sides having a toothed profile fitting with the longitudinal embossments to allow securing the closure element to the conducting plate and sealing the longitudinal opening , assuring the leak-tightness of the longitudinal cavity ; ∘ a longitudinal seat which is configured to press the hydraulic pipe against the groove , assuring the thermal energy transfer between the hydraulic pipe and the conducting plate ; and ∘ a lower base which is flush with the lower face . <EOS>