This paper presents a methodology that allows for calculating the thermal and electric energy consumption together with CO2 emissions of cities by inhabitant and household based on climate, only making use of publicly available data. With this aim, climate was analysed and cities were classified based on it. The analysis of those cities' energy consumption and CO2 emissions allowed for drawing conclusions. Once aware of the climate zones in which energy consumption and emissions are higher, these mentioned conclusions could help to take further actions. An index has been defined to facilitate this analysis. This paper shows the case of Spain for illustrative purposes. This type of study has been carried out in some detail in many countries, but not in Spain yet. This paper tries as well to fill the existing gaps in studies that relate climate to thermal and electric energy consumption. For this purpose, it analyses the 145 cities in Spain that have more than 50,000 inhabitants. Knowing all this is essential in all regions and countries. It will allow for taking proper actions for promoting the energy saving and the use of alternative energy sources that reduce CO2 emissions. According to the study carried out in this paper, the extremer the climate of a city is, the higher the thermal energy consumption is. This consumption decreases in softer climates. However, electric energy consumption is similar in all cities independent of the climate they have. With regard to CO2 emissions, it was calculated that the higher the energy consumption of a city is, the higher these emissions are.
Keywords: Buildings; Cities; Climate; Emissions; Energy consumption; Spain.