D
DC/AC converter (Inverter)
Device for converting direct current into alternating current.
DC/DC CONVERTER
Electronic circuit to convert dc voltages (e.g., PV module voltage) into other levels (e.g., load voltage). Can be part of a maximum power point tracker (MPPT).
Deep Of Discharge
See: DOD.
Delivery point
A location or facility designated for the delivery of the electric power produced by the distributor (ENEL or Municipal Concerns).
Diffused irradiance
Component of the solar irradiance received from a light-catching surface after the reflection and dispersion due to the atmosphere.
Diffusion
Process by which the silicon cell is doped with phosphor ions to allow the creation of a superficial n-type layer on its surface; that is necessary to obtain the p-n junction, which is essential to make the PV cell function. The process of diffusion takes place in special ovens, at temperatures not inferior to 870 °C and for about 15÷20 minutes.
Diode
Electronic component that allows current flow in one direction only.
Direct irradiance
Component of the solar irradiance striking a light-catching surface with a sole defined angle of incidence.
Direct current (DC)
Electric current in which electrons flow in one direction only. Opposite of alternating current.
Direct voltage (Vdc)
Voltage between two points of a circuit maintaining the same sign and value with changing of time. It's typical of some stand-alone systems (railways, ships) as well as of battery-fed devices.
Distributed systems
Systems that are installed at or near the location where the electricity is used, as opposed to central systems that supply electricity to grids. A residential photovoltaic system is a distributed system.
DOD(Deep Of Discharge)
Discharging a battery to 20-percent or less of its full charge.
Doping
Introduction of impurities (doping elements) in very small amounts (1 out of 1.000.000) inside the semiconductor material, in order to increase its intrinsic electric properties.
