§01 — What the site demands
Conditions on wind farm and solar plant cable routes
Renewable sites are geographically large and electrically simple: many small sources collected at medium voltage and delivered to one or two grid connection points. Length, not current rating, becomes the governing constraint — on a turbine string or array feeder several kilometres long, voltage drop usually decides the cross-section. The environment adds UV, high ambient temperature, sand abrasion, coastal salt and repeated twisting of the run inside a turbine tower.
| Site circuit | Condition in service | What it fixes in the cable |
|---|---|---|
| Wind farm collection | 20 kV, 33 kV or 35 kV strings to the collector substation | MV XLPE build sized for load current and drop along the string |
| Turbine internal cabling | Vertical runs with torsional movement | Flexible conductors, secure cleating, twist loops |
| Solar array DC feeders | DC at maximum voltage including open-circuit voltage at the lowest temperature | Insulation rated for DC stress, UV- and heat-resistant sheath |
| Inverter output and auxiliaries | 0.6/1 kV AC, grouped in trenches or on racks | Derating for grouping and ambient |
| Exposed and above-ground sections | Direct sun, high ambient, sand or salt | UV-stabilised sheath, temperature-corrected rating |
| SCADA and communications | Long distances to the control building | Optical fibre on the structures or in the trench |
On long collection circuits the first calculation is voltage drop. Sizing on current alone gives cable that is thermally adequate and electrically unusable.
§02 — Recommended cable families
Families that match renewable duties, and why
MV XLPE for collection networks
Collector circuits linking turbines or block substations to the grid connection point run at 20 kV, 33 kV or 35 kV: see 33 kV XLPE cable and the MV range.
LV XLPE for inverter outputs
Inverter-to-transformer connections and balance-of-plant loads run at 0.6/1 kV under IEC 60502-1, corrected for ambient and grouping: see LV XLPE power cable.
Low-smoke cable in enclosures
Inverter stations and control buildings call for low smoke and acid gas, measured by IEC 61034 and the IEC 60754 series: see LSZH control cable.
Control cable for monitoring
Pitch and yaw control, inverter signalling and metering travel beside power cable, so screened control cable keeps interference out of instrumentation: see KVV and KVVP control cable.
Optical fibre for SCADA links
Turbine-to-substation communications and protection signalling run on fibre, unaffected by lightning and switching transients: see ADSS and OPGW aerial fibre.
Armoured construction for trenched routes
Trenched collection circuits use steel-tape armoured cable, with a UV-resistant sheath at above-ground transitions: see YJV22 armoured power cable.
§03 — Selection checklist
Decisions that change cost and availability
| Decision | What has to be settled | Consequence if ignored |
|---|---|---|
| Voltage drop | Cross-section checked at the actual string length and load | Adequate rating but unusable voltage at the far end |
| Ambient derating | Rating corrected to the site’s design maximum ambient | Cable above its rated conductor temperature in summer |
| Grouping | Number of circuits touching in trenches or on racks | Underestimated heating across the whole site |
| UV exposure | UV-stabilised sheath on any unburied section | Sheath cracking and chalking within a few seasons |
| Conductor material | Aluminium or copper, with matching lugs and jointing practice | Termination problems and corrosion at joints |
Derating factors for ambient temperature and grouping come from the wiring rules the project adopts, typically IEC 60364-5-52 or its local equivalent. Name the document.
§04 — Questions from EPC and developer engineers
Frequently asked questions
Aluminium or copper for array and collector feeders?
Aluminium is lighter and usually cheaper per ampere on long runs, suiting trench-based collection circuits; copper is easier to terminate and tolerates repeated handling. Lugs, jointing compound and tooling must match the conductor, and bi-metallic transitions must be specified where the two meet.
How much derating is needed for a hot climate site?
It depends on the design maximum ambient temperature, the laying arrangement and the number of grouped circuits — there is no single figure. Provide the site’s temperature data and trench layout and ratings follow from the wiring rules.
Do above-ground sections need a different sheath?
Yes. Exposed runs need a sheath compound stabilised against ultraviolet radiation, identified by carbon-black content or a UV-resistance test, and the rating has to be corrected for solar gain in full sun.
Why is fibre preferred for site communications?
Routes are long and share the electromagnetic and lightning environment of the power circuits. Fibre is immune to induced voltage, needs no surge protection along the route, and carries SCADA, protection signalling and video on one cable.
§05 — Next step
From site layout to a quotation
A workable enquiry carries the collection voltage, the string or array layout with lengths, load per circuit, temperature and UV conditions, and the installation method per section. Drum lengths matter too, since long runs are supplied in drum multiples. A typical distribution project brief shows the input level that makes quotations comparable; our testing and certification page lists the documents supplied per shipment.
Send the layout and site conditions and we will return construction and drum planning: Request a quotation →