Every farm installation should follow the same disciplined process. A good installer does not rush the early stages — most cost overruns and underperforming systems come from skipping the desk feasibility and structural survey. By the time it sends a fixed-price proposal, it should already know the answer.
Farm solar — quote to commissioning
- 01Day 1–3
Free desk feasibility
You send us a recent electricity bill and ideally half-hourly meter data, plus roof drawings or a Google Earth screenshot. Send your details through the quote form and we will reply by email.
- 02Week 2–3
Site survey
Structural and electrical engineers from the installer visit the farm to measure roofs, test cable runs, photograph the supply intake, check three-phase status and identify asbestos. ~3 hours on site.
- 03Week 3–4
Fixed-price proposal
Full design pack: panel layout, inverter spec, structural calcs, grid connection forecast, AIA modelling, total cost, payback table. Valid 90 days.
- 04Week 4–5
Order acceptance + deposit
15% deposit secures the project and locks in panel pricing. Asbestos survey or DNO budget enquiry triggered.
- 05Week 5–14
DNO application + planning
The installer submits G99 (or G98 for sub-16A/phase) to your DNO — UKPN, NGED, SSEN, SPEN or Northern Powergrid. Planning if needed (most farm roof installs are permitted development).
- 06Week 5–10
Grant and tax check
No grant for farm solar panels is open in 2026 (in England the IFP round closed to full applications on 31 July 2025), so the proposal should not assume one. Most farms can deduct the whole cost in year one through the £1 million Annual Investment Allowance.
- 07Week 14–22
Installation
On-site 1–6 weeks depending on system size. Typical 50kW barn-roof install: 2 weeks. 200kW multi-building: 4–5 weeks.
- 08Week 22–24
Commission + handover
Commissioning tests, DNO sign-off, MCS certificate issue, SEG registration, monitoring dashboard activated, farm-team training session.
What you do vs what a good installer does
Your responsibilities
- • Provide recent electricity bills + meter data
- • Approve roof access for survey
- • Sign proposal + pay 15% deposit
- • Maintain safe site access during install
- • Sign off commissioning paperwork
A good installer handles
- • All structural and electrical surveys
- • DNO grid connection application (G98 or G99)
- • Planning (where required)
- • Confirming grant status (no farm solar grant is open in 2026)
- • Asbestos removal coordination
- • Scaffold, install, commissioning, monitoring
- • MCS certification, SEG registration
- • Annual servicing for 5 years post-install
Working around the farming calendar
A good installer plans installations around your operations. Dairy installs avoid milking-parlour disruption — typically scheduling roof work between morning and afternoon milkings, with electrical isolations under 30 minutes. Arable installs are scheduled around harvest and drilling windows. Poultry installs avoid placement and depopulation weeks. Lambing-shed work is sequenced for September–February only.
What gets checked during the structural survey
The structural survey is the stage that decides whether the project proceeds, and a reputable installer will refund the survey deposit if the roof fails it. Expect the surveyor to inspect:
- ✓ Purlin spacing and condition — typically 1.2–1.8m centres on modern portal frames; older barns may need additional purlin runs
- ✓ Rafter load capacity — calculated against panel weight (12–15 kg/m²) plus wind uplift to BS EN 1991-1-4 standard
- ✓ Asbestos cement identification — visual inspection plus optional bulk sample. 18% of UK farm barns still have ACM roofing. Licensed removal scheduled separately.
- ✓ Roof sheet age and condition — fixings, laps, weatherproofing. Older composite panels may need replacement before solar to avoid double cost later.
- ✓ Eaves and ridge access for safe install — scaffold loading points, MEWP access routes, fall-arrest provision
- ✓ Internal weatherproofing — penetration sealing strategy on insulated composite vs single-skin roofing
DNO grid connection deep-dive
Grid connection is often where a farm solar timeline slips. Knowing your DNO's quirks matters:
- UKPN (London, East of England, South East) — applications go through its online portal; ask for current connection times.
- NGED (formerly WPD — Midlands, South West, Wales, South Wales) — large agricultural footprint. Ask for current connection times; capacity varies by area, so check its network capacity map.
- SSEN (Scotland north of Central Belt, southern England) — connection times vary by area; islands and remote rural sites can attract higher connection charges.
- SPEN (Manweb area / North Wales / Scotland central belt) — ask for current connection times.
- Northern Powergrid (Yorkshire, North East) — ask for current connection times.
- NIE Networks (Northern Ireland) — G98 for the smallest systems, G99 above that; ask for current connection times.
Commissioning checklist — what should be signed off before handover
- 1. DC string voltage and polarity tested at each combiner
- 2. Insulation resistance to BS 7671:2018+A2 standard (typically >40 MΩ)
- 3. Inverter performance verified against ramp-up curve under load
- 4. Grid-tie protection (G99) function tested with DNO witness if required
- 5. AC RCD trip times verified (typically <200ms)
- 6. Export limitation device (where fitted) calibration test
- 7. Monitoring dashboard activation + farm-team login test
- 8. Battery state-of-charge calibration cycle (if specified)
- 9. Earthing continuity verified across full DC and AC arrays
- 10. EPC certificate issued (if commercial-rated property)
- 11. MCS certificate uploaded; SEG application submitted
- 12. As-built drawings + O&M manual handed over physically and digitally
- 13. Farm-team training session (typically 60–90 minutes on monitoring + fault response)
- 14. First-quarter performance review scheduled at 90 days post-handover