Exploring Design, Technology, & Engineering © 2012 Chapter 21: Energy-Conversion Technology—Terms and Definitions active solar system: a system using moving parts to capture and use solar energy. It can be used to provide hot water and heating for homes. anode: the negative side of a battery. cathode: the positive side of a battery. chemical converter: a technology that converts energy in the molecular structure of substances to another energy form. conductor: a material or object permitting an electric current to flow easily. conservation: making better use of the available supplies of any material. electricity: the movement of electrons through materials called conductors. electromagnetic induction: a physical principle causing a flow of electrons (current) when a wire moves through a magnetic field. energy converter: a device that changes one type of energy into a different energy form. external combustion engine: an engine powered by steam outside of the engine chambers. fluid converter: a device that converts moving fluids, such as air and water, to another form of energy. four-cycle engine: a heat engine having a power stroke every fourth revolution of the crankshaft. fuel cell: an energy converter that converts chemicals directly into electrical energy. gas turbine: a type of engine that creates power from high velocity gases leaving the engine. heat engine: an energy converter that converts energy, such as gasoline, into heat, and then converts the energy from the heat into mechanical energy. internal combustion engine: a heat engine that burns fuel inside its cylinders. jet engine: an engine that obtains oxygen for thrust. mechanical converter: a device that converts kinetic energy to another form of energy. passive solar system: a system that does not use moving parts to capture and use solar energy. rocket engine: a reaction engine based on a principle of physics. Solid fuel and liquid fuel are the two major types of rocket engines. solar cell: a device that converts the energy from sunlight into electric energy. solar converter: a device that converts energy from the Sun to another energy form. step-down transformer: a transformer reducing the voltage of electric current. step-up transformer: a transformer increasing the voltage of electric current. Copyright Goodheart-Willcox Co., Inc. Permission granted to reproduce for educational use only. thermal converter: a device that converts heat energy to another form. transformer: a device that can increase or decrease the voltage (force) of electric current. transmission: the act of moving energy to where it performs work. Trombe wall: an 8″–16″ thick masonry wall with a layer of glass mounted about 1″ in front of the wall. turbine: a device that transforms energy from a flowing stream of fluid into rotating mechanical energy. water turbine: a device that uses the energy of moving water to make electricity. Copyright Goodheart-Willcox Co., Inc. Permission granted to reproduce for educational use only..