Thermal Energy Storage (TES) provides us with a flexible heating and/or cooling tool to combat global warming through conserving energy while utilising natural renewable energy resources. This paper aims to show how CO2 emissions can be decreased by utilising different TES concepts in Turkey. The first project is for the heating and cooling of a supermarket using Aquifer Thermal Energy Storage (ATES) in Mersin. With a 60% higher Coefficient of Performance (COP), the yearly CO2 emissions reduction contribution of this project is 113 tonnes. The second project concerns ATES for the heating and cooling of a greenhouse in Adana. The greenhouse was used as a 'solar collector' and source of energy for the ATES system. No fossil fuels were consumed for heating the greenhouse and cooling was made possible with the ATES system. Energy conservation amounted to 68% and CO2 emissions were reduced by 26 tonnes/year. The third one is a pilot project using TES in microencapsulated phase change materials in a test cabin in Adana with a floor area of 4 m(2). By using a 3.5 kg Phase Change Material (PCM) together with insulation panels in the test cabin, 7% cooling energy and 28% heating energy can be conserved. The corresponding CO2 emissions reduction would be 0.5 tonnes/year.