CLIMATE CHANGE. Global variation of the Earth’s climate directly or indirectly attributable to human action on the natural environment.

CNMV (CUBG). Acronyms for the Spanish Stock Markets Commission (Comisión Nacional de Mercado de Valores) and the Unified Good Governance Code (Código Unificado del Buen Gobierno).

CO2. Carbon dioxide, the main component of greenhouse gases, which in excessive quantities contribute to global warming of the planet (climate change).

COAL. Sedimentary rock of organic origin widely used as a fossil fuel or raw material in thermal power stations. Thermal power stations using pulverized coal are the main source of electrical energy in the world. In recent years, other kinds of coal power stations have been developed in order to increase capacity and reduce polluting emissions, such as those using pressurized fluidized bed combustion. Another upcoming technology is combined cycles, which use synthetic gas as a fuel obtained through the gasification of coal.

COGENERATION. Joint production of electrical and usable thermal energy from the same plant.