What do 6 solar panels cost including installation in 2026?

Six 435 watt-peak panels are 2,610 Wp together. With the rule of thumb of 0.85 to 0.9 kilowatt-hours per watt-peak per year you land around 2,300 kWh, on a south roof at a favourable pitch. That is the same sum as in our guide to solar panel yield, following the common yield assumptions (Dutch).

East-west, shade or a flatter angle yields less. What that does on your bill depends on how much you use yourself during the day. Panels generate mainly by day; evening power from your own generation needs a home battery.

Six panels with a string inverter is the simplest set: one box, one string, one monitoring point. That fits one unshaded roof face. Micro-inverters or optimisers per panel cost more to buy, because you purchase six inverters or six optimisers instead of one string box.

That extra is worth it if a chimney, dormer or tree hits part of the row, or if you have two faces. Otherwise you pay extra without extra kWh. Ask for the reason on the quote, not only the line.

On a flat roof the panels sit in ballasted frames, usually at 10 to 15 degrees. You need extra material, extra fitting time and often a longer cable run. That is why a set of six on a flat roof sits higher than the same six on a reachable tiled pitch. How the frames, ballast and south versus east-west work is in solar panels on a flat roof.

The structure must take the ballast. That is not a sales extra: without that check you put weight on a roof that may not carry it.

Six 400 Wp panels are 2,400 Wp together, or 2.4 kWp. That is less power than six at 435 Wp. With the same rule of thumb you land roughly between 2,040 and 2,160 kWh a year, again on a south roof. Watt-peak is not a kilowatt-hour: Wp is the lab rating of the panel, kWh is what the year yields.

On a small roof 400 Wp can still fit if the modules are physically smaller. Compare quotes on total power and expected kWh, not on the number six alone. Eight panels are a different set: more modules, a different inverter, different fitting. That price does not belong on this page.

Ask for at least three proposals with the same starting points: count, Wp per panel, inverter type, roof type and whether the meter cupboard is included. Divide the all-in price by total watt-peak when you put two comparable sets side by side. A set with micro-inverters is not the same set as a string.

Check that scaffold, monitoring and warranty per part are in. If a line is missing, it comes later as extra work.

Six solar panels including installation have no catalogue price. The sum is panels plus inverter plus fitting, and the last two move hardest with a flat roof, shade or a tight meter cupboard. What the set yields, you read in kWh, not in a figure we invent here.

Want those lines split out for your roof? Put your situation to us and we will calculate with your meter and roof.