Solar panels per Watt peak costs

When you think about buying solar panels, there are many terms to read through. One of these is Watt peak and this term is used as a unit to express the cost of solar panels. Buying solar panels isn’t cheap, but if you can afford it, it is definitely a good investment. You can generate your own energy, making you less dependent on fossil fuels. You will also earn back money on your energy bill. Here you can read about the costs of solar panels per Watt peak (Wp).

What is Watt peak exactly?

Watt peak is used to calculate the power of solar panels. The number of Wp indicates how much energy the solar panels can generate. The higher the number of Wp, the better the solar panels’ output. These are internationally established standards. For example, you’ll generate less energy in the Michigan than in the south New Mexico. This has to do with the strength of the light, the temperature, the angle of the sun’s rays and also the solar spectrum.

Converting watt-peak to kWh

The number of Wp per solar panel is the same per country. However, it is different when you are going to convert it to kWh, so you can calculate how many solar panels you need to cover your annual energy consumption.

The costs

Now for the costs. Are you planning to buy solar panels, it’s wise to ask yourself how much kWh you want to generate annually. This certainly doesn’t have to be everything. Even if you generate part of your energy with solar panels, you’ll benefit. The costs per Wp are given in the following table, these prices include installation and materials.

Number of Wp Number of solar panels Average price Annual yield in kWh
250 1 $655 212.5 kWh
750 3 $1855 637.5 kWh
1500 6 $4000 1275 kWh
3000 12 $6800 2550 kWh
4000 15 $8720 3400 kWh
5000 20 $10.100 4250 kWh
6000 24 $11.990 5100 kWh
7000 28 $13.300 5950 kWh


A small household: if your household consists of one or two people, you’ll consume an average of 3000 kWh of electricity per year. If you want to generate all the electricity with this, you’ll need between 12 and 15 solar panels. This will cost about $7650, including installation.

An average household: if your household consists of three or four people, you will consume an average of 4500kWh per year. To be able to generate this with solar panels, you need about 22 panels. You pay about $10,900, including installation.

A large household: large households consisting of 5 or more people can easily use 5300 kWh per year. For this you need more than 25 panels costing about $12,535.

You don’t have to use your solar panels to generate all the energy you use. Even one solar panel already provides energy ensuring you benefit.

The price structure

The costs of installing solar panels consist of materials and labor costs. Often you buy the solar panels from the supplier who will then install them and take care of the warranty. Labor costs are higher when you install more solar panels, but the material-labor ratio fluctuates around 80/20 percent. If you have fewer panels installed, the labor costs percentage will increase and if you have a large number of panels installed, it’ll decrease. Nevertheless, by far the biggest cost item is the materials. The following diagram shows this.

Choices that influence the price

When you buy solar panels, you’ll be faced with a number of choices that affect the price of your solar panels. Here are the biggest contributors.

The type of solar panel

There are different types of solar panels on the market, namely monocrystalline, polycrystalline and amorphous. The type you buy depends on your budget, but also on your situation. Amorphous solar panels are better in situations with shade, but they do need a larger roof area. Monocrystalline modules have the highest yield, and they don’t need a large surface area, but are the most expensive.

Your energy consumption

Your energy consumption, or perhaps the number of kWh that you want to generate with your solar panels, can be important as well. It is recommended that you don’t have too many solar panels installed, because then you will have to start balancing. This is an arrangement whereby you sell the energy back to your energy supplier. It is expected, that this scheme won’t go on for long and the selling price is not favorable. Think well in advance about how much kWh you want to generate.

The placement

Not all roofs are suitable for solar panels. If they’re in the shade, if they are not at a certain angle or if leaves or bird droppings are easily collected on your roof, the yield will go down. If you don’t have a suitable place for the panels in your yard, you may ask yourself if installing them is profitable enough in the first place.

Interesting savings tips

Buying solar panels is expensive. Here are a few tips to help you keep the costs down.

Compare quotations

The best way to find out how much your solar panels will cost is to request quotations. Use our comparison tool and you can save up to 30 percent on total costs. This service is free of charge and without obligation, but it can help you on your way to your new solar panels.