Solar Panel Prices in Kenya: 350W, 420W, 485W and 550W Compared by Cost per Watt
Our solar panels cost KSh 18,200 for a 350W module, KSh 18,480 for 420W, KSh 21,340 for 485W and KSh 28,600 for 550W. Divided by wattage, the 420W and 485W panels both work out at KSh 44 per watt, while the smallest and the largest, the 350W and 550W, both come to KSh 52 per watt. If you are buying on cost per watt, the two middle sizes are the cheapest way to buy generation.
Solar panel prices per watt
| Panel | Price | Cost per watt |
|---|---|---|
| 350W solar panel | KSh 18,200 | KSh 52 |
| 420W solar panel | KSh 18,480 | KSh 44 |
| 485W solar panel | KSh 21,340 | KSh 44 |
| 550W solar panel | KSh 28,600 | KSh 52 |
The 420W panel is the standout: it costs only KSh 280 more than the 350W but gives you 70 more watts.
Unlike solar flood lights, where the "W" on the box is a marketing figure (see solar flood light wattage explained), a module's watt rating is the figure array designers work from, so comparing price per watt is a fair test between panels.
How many panels for a 1 kW, 3 kW or 5 kW array
Panels come in whole numbers, so the cheapest panel per watt does not always give the cheapest array. The table below rounds up to the fewest panels of each size that reach the target, and prices the panels alone.
| Target | 350W | 420W | 485W | 550W |
|---|---|---|---|---|
| 1 kW | 3 panels, 1,050W, KSh 54,600 | 3 panels, 1,260W, KSh 55,440 | 3 panels, 1,455W, KSh 64,020 | 2 panels, 1,100W, KSh 57,200 |
| 3 kW | 9 panels, 3,150W, KSh 163,800 | 8 panels, 3,360W, KSh 147,840 | 7 panels, 3,395W, KSh 149,380 | 6 panels, 3,300W, KSh 171,600 |
| 5 kW | 15 panels, 5,250W, KSh 273,000 | 12 panels, 5,040W, KSh 221,760 | 11 panels, 5,335W, KSh 234,740 | 10 panels, 5,500W, KSh 286,000 |
Three things stand out:
- At 1 kW the 350W is cheapest, because three of them land just above 1,000W with little wasted. The 420W is only KSh 840 more and gives you 210W of headroom.
- At 3 kW and 5 kW the 420W wins, saving KSh 51,240 against the 350W and KSh 64,240 against the 550W on a 5 kW array.
- The 550W is never the cheapest on panel cost. It earns its place on fewer mounting points, not on price.
Why the biggest panel is not always the cheapest system
Panel cost is only part of the bill. As general guidance, every panel needs its own clamps, a share of rail and a share of labour, so fewer, larger panels can save on mounting. Against that, larger modules are heavier and harder to lift onto a roof, and a string of large panels may suit one inverter's voltage window and not another's. On a house or shop roof with a modest array, that saving rarely outweighs the KSh 8 per watt premium.
Handling: plan for two people
Our 485W listing says to treat it as a two-person module, the 420W is described as mounted by a crew rather than one person on a ladder, and the 550W listing says to plan for the weight and area of a module that size before quoting the job. Our listings do not publish dimensions or weights, so check the actual panel at our counter before planning a roof lift.
Mounting and shade
The four listings give consistent mounting advice: use proper rails or a ground frame (all four), fix to the frame rather than the laminate (420W and 485W), leave space for air behind the panel (350W and 420W) and keep the array free of shade (350W and 485W), since one shaded panel limits the string it sits in. The 550W listing adds that you should check string open-circuit voltage against the inverter limit with the coldest morning in mind, and design in access for cleaning, since dust quietly takes the output away.
Which panel size suits which inverter
Match the array to the inverter's PV input limits first and the panel price second. Our listings do not publish the panels' open-circuit voltage (Voc), operating voltage (Vmp) or cell type. Modules in this class typically have a Voc somewhere in the high 30s to around 50V, but treat that as a typical range only and confirm the label on the panel you buy before wiring a string.
| Inverter | Price | PV limits from the listing | Panel fit |
|---|---|---|---|
| STS20224 2000W, 24V | KSh 62,000 | Up to 1,600W of PV; Voc under 100V DC; MPPT 30 to 85V DC | A 1 kW array of three 350W or 420W panels sits within the wattage limit. The low voltage limit means short strings. |
| STS50248 5000W, 48V | KSh 116,000 | Up to 4,400W of PV; Voc under 145V DC; MPPT 60 to 115V DC | A 3 kW array of eight 420W or seven 485W panels fits the wattage limit, in several short strings. |
| 8200W hybrid STM82248, 48V | KSh 140,000 | Voc up to 500V DC; MPPT 90 to 450V DC, full load 360 to 450V DC; one tracker, 27A max input | The higher-voltage design suits longer series strings, which is where 5 kW arrays of 420W, 485W or 550W panels belong. Confirm the string's open-circuit voltage stays under 500V DC before fixing the panel count. |
Note that a 5 kW array is larger than the STS50248's 4,400W PV limit, so a 5 kW plan points to the 8200W hybrid. Working out how many panels go in series and in parallel for each inverter is covered step by step in how many solar panels per inverter. If you have not chosen the inverter yet, start with what size inverter for a house in Kenya, and if you are still deciding between a kit and a full system, read solar home system or inverter.
Which solar panel size to buy
- Small system, about 1 kW: three 350W panels are the cheapest; three 420W panels cost KSh 840 more for extra headroom.
- Home or shop array, 3 kW to 5 kW: the 420W panel, the best price per watt with fewer panels than the 350W.
- Tight roof area, want maximum watts per panel at a good price: the 485W, at the same KSh 44 per watt as the 420W.
- Large commercial or ground-mounted array: the 550W, where fewer mounting points matter more than the per-watt premium.
Where to buy
All four panels are in our solar panels collection, with matching units in solar inverters. Collect free from our Nairobi trade counter at Royal Business Park, opposite Complast, Old Mombasa Road, Monday to Saturday, 8:00 to 17:30, or order for countrywide delivery at a flat KSh 350, free on orders over KSh 15,000. Send your roof size and the inverter you plan to use on WhatsApp and we will help with quantities. Installers and contractors buying in volume can request a trade quote on our trade page.
Common questions
What is the price of a 350W solar panel in Kenya?
Our 350W panel is KSh 18,200, which is KSh 52 per watt. For KSh 280 more, the 420W panel gives you 70 extra watts at KSh 44 per watt.
How much is a 550W solar panel in Kenya?
Our 550W panel is KSh 28,600, or KSh 52 per watt. It suits large arrays where fewer mounting points save labour, rather than small home systems.
Can I mix panel sizes in one array?
As general guidance, avoid mixing different panels in the same string, because the string runs at the pace of its weakest module. Buy one size for each string and confirm the layout with your installer.
Can one person install a 485W or 550W panel?
Not safely. Our 485W listing says to treat it as a two-person module, and the 550W is larger still. Plan for at least two people for any roof lift.