Prates, Manuel João LopesCosta, J. CruzMendes, J. FarinhaCarvalho, Maria João2010-06-252010-06-252008-10-07Prates, M. J. Lopes; Costa, J. Cruz; Mendes, J. Farinha; Carvalho, M. J. On the sustainable development of solar thermal obligations in buildings in the framework of the Portuguese case. In: Eurosun 2008 - 1st International Conference on Solar Heating, Cooling and Buildings, Lisbon, Portugal, October 7 - 10, 2008http://hdl.handle.net/10400.9/724This paper starts remembering the steps given in Portugal to prepare the introduction of a solar thermal obligation. Next, it presents a description of the present legislation related to the Solar Thermal Obligation (STO) and to other incentive measures for growth of the solar thermal market in Portugal. The main problems with implementation of the new regulation are analysed and systematized. Based on the acquired knowledge, further actions are presented to guarantee the success of Solar Thermal Obligation, namely proposals for updating the obligation in conformity with best practice for solar thermal installations and taking into account the new realities upcoming from the actual solar thermalengThermal performanceSolar thermal obligationSolar thermal collectorsCertificationconference object