SolarSimPro
Glossary

Solar terminology glossary

In solar projects the same concept goes by different names in different teams. The glossary below defines the terms used in SolarSimPro, and in solar engineering generally, briefly and accurately.

Design · analysis · finance terms With Turkish equivalents

Design and layout

TermMeaning
Setting-out planA georeferenced, scaled drawing that allows the design to be set out on site. It contains the site and setback corner coordinates, the layout and the title block.
SetbackThe distance left inside the site or roof boundary. It defines the buildable area.
Mounting tableThe structure that carries the modules on a ground-mounted plant. Its arrangement is usually expressed as "rows × modules" (for example 3×26).
Row spacing (pitch)The distance between two module rows. Increasing it reduces shading loss and lowers ground coverage.
AzimuthThe direction the module plane faces. In the northern hemisphere, south generally gives the highest yield.
Ground coverage ratio (GCR)The ratio of module area to the ground area it occupies.

Terrain and topography

TermMeaning
SlopeThe angle a surface makes with the horizontal, given in degrees or per cent.
AspectThe direction a sloping surface faces. South-facing surfaces are advantageous for yield.
Contour (line of equal elevation)A line joining points at the same elevation — the most direct way to read the shape of the ground.
ElevationThe height of a point above sea level.
DEM (digital elevation model)Digital data holding the elevation of the terrain as a grid.
TUREF / TM 3°The Turkish national projected coordinate system, based on the Turkish National Reference Frame and divided into 3-degree zones. Used for setting-out drawings in Türkiye.

Yield and performance

TermMeaning
kWpKilowatt-peak: the total DC power of the modules under standard test conditions.
Specific yieldAnnual yield per unit of installed capacity (kWh/kWp) — the common measure for comparing plants of different sizes.
Performance ratio (PR)The ratio of actual yield to the theoretical loss-free yield. It summarises how well the system performs.
P50The yield expected to be exceeded in half of all years — the expected (median) scenario.
P90The yield expected to be exceeded in 90% of years — the conservative figure used in financing.
Near shadingShadows cast by nearby objects — parapets, chimneys, trees, adjacent rows.
DegradationThe gradual loss of module power over the years, usually given as an annual percentage.

Finance and commercial

TermMeaning
NettingOffsetting generated energy against consumption. It can be done hourly or monthly, and the choice noticeably affects the payback period.
Self-consumptionThe share of generated energy used on site immediately.
Payback periodThe time an investment takes to pay for itself, calculated both simple and discounted.
NPV (net present value)The discounted sum of future cash flows minus the capital cost.
IRR (internal rate of return)The discount rate at which net present value equals zero.
CAPEX / OPEXCapital expenditure / operating expenditure.
Progress weightingThe percentage weight of each work item within the total scope. Used for progress payments and tracking.
Bill of quantities summaryA summary table of material and work items by category.

The best way to learn the terms is to see them in a project

Let us run a session on your own project and follow the concepts on screen together.

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