Cleantech; clean energy: Products, processes, and services that depend on renewable energy sources, minimize waste, and use natural resources judiciously.

Climatologist: Scientist who studies long-term climate variations by looking at past weather data and using complex computer models and datasets to project how various factors such as greenhouse gases, volcanic activity, and solar flares impact our climate.

Concentrating solar power (CSP): Typically used in utility-scale projects, CSP uses a large array of mirrors to focus sunlight onto receivers. As the receivers collect the solar energy, they convert it to heat. Several designs are in use, including a mirrored dish, a power tower with mirrors encircling the tower, and linear trough systems.

Cradle to cradle model: Production life cycle wherein materials from outdated models become an input to the production process.