Checklist before installing a solar plant

Good preparation shortens the time to a quote, reduces the risk of surprises and gives you a better basis for comparing offers from different installers. Go through this list before the first conversation.

1. Consumption and bills

• Electricity bills for the last 12 months (all metering points).
• If available: 15-minute or hourly consumption data (ask your supplier or grid operator).
• Do you know whether you are on public or market supply, and what the pricing model is?
• Does your bill include billed (peak) demand and excess reactive energy? (See how to read your bill.)
• Operating hours: weekdays, weekends, shifts, seasonal shutdowns.
• Planned changes in consumption over the next 2–3 years (new machinery, cooling, EV chargers, heat pumps).

2. Grid connection

• The building’s approved connection capacity (from the connection approval or contract) — plant size must not exceed it.
• Connection voltage level (low voltage 0.4 kV or medium voltage).
• Who your distribution system operator is (in the Federation of BiH: Elektroprivreda BiH or Elektroprivreda HZ HB; in Republika Srpska: distribution companies within the Elektroprivreda RS system).
• Location of the main switchboard and the meter.

3. Roof or land

• Ownership — do you own or lease the building/roof? Do you need consent from the owner or co-owners?
• Roof type: flat, pitched, metal sheet, tiles, sandwich panels; type and condition of waterproofing.
• Roof age and condition — panels stay 25+ years; is refurbishment planned?
• Structure — are there building drawings or a structural calculation?
• Shading — chimneys, vents, neighbouring buildings, trees, future construction.
• Roof access for installation, maintenance and cleaning.
• For ground-mounted plants: land ownership, zoning, access road, distance to the connection point.

4. Permits and regulations

• The entity’s prosumer regime has been checked (see Prosumers in the Federation of BiH and Republika Srpska).
• Cantonal/municipal building and use requirements have been checked (permit or confirmation that none is required).
• For protected buildings or special zones: additional conditions.
• Fire-safety requirements and insurance — inform your insurer about the planned plant.

5. Goals and budget

• What is the main goal: a lower bill, predictable costs, customer requirements (emissions), backup power?
• Indicative budget and target payback.
• Financing model: own funds, loan, leasing, third-party ownership.
• Who decides in the company and what do they need (study, calculation for the bank)?

6. What to ask for in a quote

• Plant size (kWp) and the sizing rationale based on your consumption.
• Annual yield estimate and self-consumption share, with assumptions stated.
• Manufacturer, model and warranties for panels and inverters (product and performance warranty).
• What is included: documentation, approvals, mounting, electrical works, protection, monitoring.
• Delivery time and payment terms.
• Workmanship warranty and after-sales support terms.

More questions for the installer are in Questions to ask your solar installer.

7. After commissioning

• Access to production monitoring (app or web portal) and a contact for reporting faults.
• Full as-built documentation, test certificates, warranty documents.
• A plan for periodic inspections and cleaning.
• Check the power factor on the first bills after connection — a solar plant can change the ratio of active to reactive energy.

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Once you have this information, send us an enquiry — the more complete the list, the more accurate the first estimate.