The Centro para Investigaciones Energéticas, Medioambientales y Tecnológicas (Centre for Energy, Environment and Technology Research, CIEMAT), an Organism of the Spanish Ministry of Science and Innovation, is a Public Research Agency that is mainly focused on the energy and the environment, but also conducts studies into many advanced technologies and in various areas of fundamental research. Its staff numbers upward from 1200.
The CIEMAT is the successor of the Junta de Energía Nuclear (JEN), founded in 1951 by a Decree (dated October 22, 1951) with the purpose of studying the pacific application of nuclear energy and ionizing radiation.
In 1986, the organization was renamed CIEMAT, and its scope was enhanced to include other forms of alternative energy, to study the environmental impact of energy generation, and to develop associated technologies. 
CIEMAT focuses on research and technological development projects, serving as a reference for the technical representation of Spain in international forums, and advising government on matters within its field of competence. Its main goals are:
- To develop alternative energy sources
- To improve energy efficiency and optimize energy generating systems
- To improve the efficiency and reduce the environmental impact of fossil fuels
- To improve the safety of energy generation by nuclear fission
- To study the feasibility of nuclear fusion as a future energy option
- To improve the competitiveness of renewable energy sources in the energy market
- To develop solutions for improving the environmental quality
CIEMAT possesses three research centres:
- The main establishment is in Madrid (Moncloa), and that is where the Laboratorio Nacional de Fusión is located.
- The Solar Platform in Almería  - the largest solar energy plant in Europe, located in the Tabernas Desert.
- The Centre for Renewable Energy Development in Soria.