What size solar inverter and battery do I need?

Felicity's catalogue here holds all three parts of a solar system — 78 inverters, 91 lithium batteries and the GK-1-72HTBD-580M panel of 580 W — so the sizing below ends in a model code for each part, with the number of batteries and panels beside it.

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From your rooms to three Felicity model codes

Whatever you enter, the tool boils it down to two numbers. The first is the hardest instant, when every motor starts together, and it decides the inverter: the lowest-rated of Felicity's 14 single-phase hybrids (IVGM and T-REX series, 3–8 kW) that still covers it or, once you say the site has no mains, the lowest-rated of the 22 off-grid inverters on one phase (2–12 kW). The second is the energy the building uses: over the hours without mains for the battery bank, over the whole day for the array.

A battery is matched on voltage before capacity. The T-REX-3KLP1G01 states a battery window of 40–60 V; of the voltages Felicity's lithium names carry (12.8, 25.6, 51.2, 102.4 and 832 V), what that window admits is 51.2 V, on 52 listings. From there the tool keeps a single model, in as few units as hold your hours.

The array is counted in one panel, the GK-1-72HTBD-580M (580 W), and the result states the roof it covers. Past 8 kW on one phase with mains present, this catalogue has no single-phase hybrid left to name, so the inverter line shows the kilowatts needed without a code. Leaving the panels out and sizing storage alone is one of the tool's options.

Each code in a result is a link to its page, where the specification table and the price are printed; that price is the price of the unit, and the order is picked up at our Dubai or Riyadh store. Read the result as a parts list to plan with: cable sizes, protection and commissioning are the work of a licensed electrician in the country where the system goes in.

Worked results, in Felicity units

Apartment for a 4-hour evening outage. Its motors pull 4.85 kW at switch-on and its day adds up to 13.8 kWh; the lowest-rated hybrid that covers that pull is the IVGM5KLP1G1 (5 kW, battery window 40–60 V). The hours asked for rest on one FLH48100UMG1 lithium battery (5 kWh nominal, 51.2 V); the day is put back by 6 × GK-1-72HTBD-580M, which is 3.03 kWp on about 16 m² of roof. The Felicity units come to AED 8,065 together.

House, off the grid entirely. With no mains to lean on, the calculator leaves the hybrids and takes the IVAM10048P1G1, a 10 kW off-grid inverter, then stores a whole day of use: 2 × FLA48500 lithium batteries (50 kWh nominal, 51.2 V). Recharging it takes 11 panels of 580 W (5.94 kWp, about 29 m²).

House for 8 hours of night without mains. Here the start reaches 8.05 kW, above the 8 kW where Felicity's single-phase hybrids stop, so the inverter line reads 9 kW with no code. The other two lines keep theirs: one LPBA48350TG1 lithium battery (17.92 kWh nominal, 51.2 V) and 10 × GK-1-72HTBD-580M.

Behind those results: the single-phase hybrids are priced AED 2,366 (T-REX-3KLP1G01) at the low end, AED 4,984 (IVGM8KLP1G1) at the top; the single-phase off-grid inverters, AED 959 (IVCM2012P1G2) at the low end, AED 3,346 (IVBM8048P1G1) at the top.

Lithium, by the voltage in the name: 8 at 12.8 V (1.28–3.75 kWh), 23 at 25.6 V (2.5–12.5 kWh) and 52 at 51.2 V (2.56–25 kWh). The GK-1-72HTBD-580M costs AED 361 a panel.

Felicity kits the calculator has already worked out

Sizing with Felicity units: panels, battery, load

How many solar panels and how much battery does a home need?

The array has to give back in one day of sun what the home uses in a day, and the battery has to hold the hours without mains. 13.8 kWh a day (apartment) with 8 hours of night to cover comes to 6 panels of 580 W on about 16 m² and 9 kWh of lithium, 25.4 kWh a day (house) with 8 hours of night to cover comes to 10 panels of 580 W on about 26 m² and 16.1 kWh of lithium and 49.5 kWh a day (villa) with 8 hours of night to cover comes to 19 panels of 580 W on about 49 m² and 22.5 kWh of lithium. Enter your own rooms above and both figures follow your list.

What battery size does the calculator give as the outage gets longer?

The hours move the battery, not the inverter. The apartment profile sized for 4 hours installs 4.5 kWh — FLH48100UMG1; sized for 8 hours it installs 9 kWh — FLA48200. The array stays at 6 panels in both.

How does the tool work out the load before it picks an inverter?

It adds two things for every appliance: what it draws while running, and the extra a motor pulls as it starts. The apartment profile comes to a 4.9 kW peak and lands on the IVGM5KLP1G1, rated 5 kW; the villa profile peaks at 11.7 kW and needs 12 kW, which the result states as a rating.

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