7. Glossary#
- AC#
- AC Electricity#
- Alternating Current#
- Alternating Current Electricity#
Electricity (current and voltage) that oscillates, like that supplied by the municipality or Electricity Supplier (like Eskom in South Africa). It is a flow of electrical charge (electrons) that periodically changes direction. The frequency of alternation is typically 50 or 60Hz.
- Atmospheric Turbidity*#
See Turbidity
- Battery#
A device that stores electrical charge (electrons). A battery is said to be charging when it is accepting electrons - current that flows into the battery. A battery is discharging when it releases electrons - current flowing away from the battery.
- Break-Even Date#
The projected future date at which all CapEx and OpEx PV Plant costs are paid back with Grid Energy Supply savings having supplemented Load Demand with Solar Power.
- CapEx#
- Capital Expenditure#
The financial cost of a PV Plant which is an asset in a balance sheet.
- Cashflow#
The net cash in less cash out in a financial period
- DC#
- DC Electricity#
- Direct Current#
- Direct Current Electricity#
Electricity (current and voltage) that does not oscillate, like that from a Battery, or a Solar Panel. It is a one directional flow of electrical charge (electrons) in a conductor (copper or aluminium wire).
- EMS#
- Energy Management System#
Coordinates in real time, the supply of energy from the various energy sources in a PV Plant, deciding how much of each is needed, and shares the energy between supplying the Load, and charging the ESS batteries.
- ESS#
- Energy Storage System#
That component of at PV Plant used for storing energy to cover outages and reduce peak demand from the Grid
- Genset#
- Generator#
Typically an electricity generator powered by fossil fuels.
- Grid#
An electrical network supplying power. Without any defining context refers to the main supply grid for the premises.
- Insolation#
The radiant energy from the sun over a period of time.
- Internal Grid#
Without any defining context refers to Photovoltaic Plant Internal Grid
- IRR#
- Internal Rate of Return#
Is the ROI of initial investment at its Break-Even Date It often makes sense to use NPV numbers or inflation adjusted NPV numbers in these calculations.
- Inverter#
A device that takes AC or DC electrical energy and converts it to AC or DC of another form. When referred to as a a component of a PV Plant: A device that converts DC electical energy provided by PV Panels and efficiently transforms it into energy compatible with the PV Plant’s Internal Grid. Otherwise, in general terms, it is a devices that converts AC or DC electrical energy from one form to another form.
- Irradiance#
The instantaneous radiant power from the sun.
- LCOE#
- Levelised Cost of Energy#
- Levelized Cost of Energy#
Is the ratio of the total costs (both CapEx and OpEx) over a period starting with the initial investment in the PV Plant, over the total energy produced in that period. It often makes sense to use NPV numbers or inflation adjusted NPV numbers in these calculations. The period can range from one year to the lifetime of the investment, typically 25 years or more.
- Load#
That which is requiring electrical energy to operate.
- Load Demand#
- Load Energy#
The amount of electrical energy required to operate the Load
- Local Grid#
The electrical network that supplies the Load
- Modules#
Without any defining context, refers to Photovoltaic Panel
- NPV#
- Net Present Value#
Is the present value of of future amounts. For example, how much would R100 received in one year’s time be worth to me now when interest rates are 10%. The answer is R90.91, which is:
(7.1)#\[NPV = \frac{future\ value}{(1\ +\ interest\ rate)}\]- O & M Costs#
- OpEx#
- Operating Expenditure#
The costs associated with operating and maintaining an asset such as a PV Plant. It is an expense in an income statement.
- Panel#
Without any defining context, refers to Photovoltaic Panel
- PV Module#
- PV Panel#
- Photovoltaic Module#
- Photovoltaic Panel#
A Photo Voltaic devices that convert sun’s insolation into electrical energy.
- PVP#
- PV Plant#
- Photovoltaic Plant#
A Solar Energy Supply installation comprising a combination of Modules, Inverters, Energy Storage System(s), and Genset(s).
- PV Plant Capacity#
- Photovoltaic Plant Capacity#
The name-plate capacities of the modules and or inverter of a PV Plant. A PV plant with 100 – 500Wp modules is said to have a 50kWp capacity. A PV plant with 4 – 100 kW Inverters is said to have a 40kW capacity.
- PV Plant Grid#
- PV Plant Internal Grid#
- Photovoltaic Grid#
- Photovoltaic Internal Grid#
- Photovoltaic Plant Internal Grid#
The internal electrical grid of the PV Plant. Can be AC or DC or divided into separate AC and DC internal grids.
- PVS#
- PV System#
- Photovoltaic System#
An Electrical Energy System that harvests energy from the Sun to produce electricity. Typically, comprises solar panels connected to inverters.
- ROI#
- Return on Investment#
A financial management ratio of the return over the investment amount in a fiscal period starting with making the investment. this case the return is the savings by supplementing load demand with solar power, less the O & M Costs in that fiscal period.The fiscal period is anywhere from a year to the anticipated lifetime of 25 years or more. It often makes sense to calculate the net present value or net present value inflation adjusted values to use in ROI calculations.
- Solar Panel#
- Solar Power#
Irradiance from the sun converted by a PV Plant.
- Turbidity#
The reduction in atmospheric transparency due to scattering and absorption of light by aerosols.