Solar canopy & carport glossary
The terms you'll meet when you plan a solar canopy or carport — in plain English, from the installers who fit them. New to the topic? Start with the cost guide or FAQs.
- Cantilever carport
- A canopy design with support columns on one side only, so the parking bays underneath are completely column-free for easy access.
- Single-post frame
- A carport supported by a single central or side row of posts per module — the simplest, most economical steel structure for smaller runs.
- Back-to-back canopy
- Two rows of parking sharing a central column line, with panels sloping down each side — an efficient layout for double bays in large car parks.
- Mono-pitch
- A single-slope roof geometry that tilts the panels in one direction to optimise sun exposure and shed rainwater to one edge.
- Ballasted foundation
- A non-penetrating base where columns bolt to concrete or steel weights that hold the structure by gravity — used where you can't dig (membranes, services, contaminated ground).
- Ground screw
- A galvanised steel pile screwed into the ground as a fast, concrete-free foundation, each capable of supporting 2+ tonnes; suits around 90% of sites.
- Bifacial panel
- A solar module that captures light on both faces, generating extra power from sunlight reflected off the pale surface beneath the canopy.
- BIPV glazing
- Building-integrated photovoltaics — semi-transparent glass-glass modules that act as both the canopy roof and the generator, transmitting some daylight below.
- Glass-glass module
- A panel encapsulated between two panes of glass for extra durability and a longer life, ideal for exposed or architectural canopies.
- G99
- The DNO application/standard for grid-connecting systems larger than the G98 limit (over ~3.68 kW per phase) — required for most commercial canopies, with an 8–16 week lead time.
- DNO
- Distribution Network Operator — the regional grid company (e.g. UKPN, SSEN, NPg) whose approval you need before connecting and exporting solar.
- Half-hourly metering
- Settlement metering that records import/export every 30 minutes, standard for larger commercial sites and the basis for export payments and time-of-use tariffs.
- SEG (Smart Export Guarantee)
- The UK scheme under which licensed suppliers pay you for surplus solar exported to the grid — the mechanism that monetises canopy generation you can't self-consume.
- Purlin
- The horizontal steel members running across the frame's rafters that the mounting rails and panels attach to.
- Mounting rail
- The aluminium rails clamped to the purlins onto which solar modules are fixed, setting panel spacing and row alignment.
- String inverter
- The device that converts the panels' DC output into grid-compatible AC, wired in 'strings' of modules across the canopy.
- Elevation / tilt angle
- The pitch at which panels are set (often 5–15° on canopies) to balance energy yield, self-cleaning rainwater run-off and wind loading.
- EV canopy
- A solar carport with EV chargepoints integrated beneath it, so vehicles charge directly from the panels overhead — maximising valuable self-consumption.
- Membrane
- A waterproof or root-barrier layer beneath the surface (e.g. on podium decks or capped land) that rules out penetrating foundations and points to a ballasted design.
- Snow load / wind load
- The Eurocode-defined forces the steel frame must resist for its location — the structural basis for column sizing, spacing and foundation choice.