Resumen de Uso de la energía solar fotovoltaica como fuente para el suministro de energia electrica en el sector residencial
Building construction in Europe is responsible for more than 40% of the total energy consumption of the member states of the European Union (EU). In these countries, 63% of this total energy consumption is for residential uses. In Spain, the residential building sector consumes 10% (10.793 ktep) of the total energy consumption in the country.
The national Plan de Fomento de las Energías Renovables [Plan for the Development of Renewable Energies] predicts that in 2020, Spain will achieve the objectives set by Europe and obtain 22.7% of its total energy from renewable energy sources. The European Union requires all member states to elaborate a national action plan to foment the use of renewable energies in order to preserve the environment.
In recent years, the huge volume of residential buildings and the growing deficit of conventional energy sources justify actions whose purpose is to foment energy selfsustainability for residential building uses (illumination, heating, use of electrical appliances, etc.). The installation of photovoltaic installations in buildings is an interesting alternative that will smooth the way towards energy sustainability.
This PhD dissertation analyzes the legal framework in Europe and Spain, which regulates building construction and its use of renewable energies. The objective of the study described in this dissertation was to analyze the evolution of the implementation of various energy-related technologies in buildings with a special focus on solar energy.
Accordingly, from the year 1996 onwards, statistical data were obtained from the Dirección General de Programación Económica de la Secretaría de Estado de Infraestructuras [General Directorate of the Secretary of State for Infrastructure] which depends on the Spanish Ministry of Development and Public Works. This dissertation focuses on new buildings with a principally residential use. It analyzes the evolution over the years of the number of houses and residential buildings, and relates this information to the type of energy installed (electricity, natural gas, petroleum-based liquid fuel, solar energy, and coal).
After defining the average irradiation characteristics of each province in the region of Andalusia and the technical parameters of photovoltaic installation, the electrical energy that can be potentially generated was estimated. This dissertation presents the evaluation of a new model that determines the mean daily and hourly solar radiation, based on temperature. The data regarding temperature as well as the mean daily and hourly solar radiation provided by this model facilitates the design of photovoltaic solar energy installations.
After describing the building construction sector, we obtained the energy capacity of the grid-connected photovoltaic installations that can be placed on building roofs. Based on the characterization of the residential sector and the digital urban maps obtained with Google Earth, the useful roof surface of a representative sample of buildings was measured and calculated. For this purpose, relevant factors considered were building height, building type, and constraints such as orientation, tilt, location, and shade.
Once the electrical energy generated by photovoltaic installations was determined, we then studied what percentage of electrical energy for lighting purposes could be covered by solar energy. This led us to develop a model that provides a description of the evolution and behaviour of electrical energy consumption in the residential sector, specifically related to final illumination use. Statistical analysis was used to define three building types that were representative of the total number of buildings (the same ones used to obtain the energy capacity of the grid-connected photovoltaic installations on building roofs). For each of these building types, we calculated and designed the lighting installation necessary to guarantee the comfortable performance of daily activities, and thus obtained the energy consumption.
The model was then used to compare the electricity consumption generated by the exclusive use of incandescent light bulbs with the consumption that would be obtained if they were replaced by low-energy light bulbs. The results obtained can be used to support national and international energy policies such as La Estrategia de Ahorro y Eficiencia Energética en España [Strategy for Energy Conservation and Efficiency in Spain] and La Estrategia Española de Cambio Climático y Energía Limpia [Spanish Strategy for Climate Change and Clean Energy].
