“10 Things to Know Before Investing in Solar Panels for Your Home: Tips from Bouwsite Livios”

Solar panels consist of solar cells, which in turn consist of two layers with a separating layer in between. When daylight falls on such a solar cell, an electrical voltage is created between the two layers: direct current.

That direct current moves from cell to cell and from panel to panel and is transported to the inverter. It converts the direct current into alternating current that we need for our electrical appliances.

Would you like to enjoy the benefits of solar panels this summer? You now have to count on this waiting time.

Usually there is one inverter per solar panel installation, but there are also solar panels with microinverters, where each panel has its own smaller inverter. In that case, the panels are no longer connected to each other. The result: if one panel does not work due to shadow or a defect, it will not negatively affect the operation of the other panels.

Tip: Do you want (in the future) invest in a home battery? Then it is best to opt for a hybrid inverter, to which you can connect both your solar panels and your home battery.

Do you have a digital meter and do your solar panels produce more electricity than you currently consume? The surplus then goes to the electricity grid. You receive a fee for every kWh you inject into the grid. The injection rate depends on your energy supplier. If you need electricity at a time when your solar panels are not generating anything, you simply get power from the grid.

Do you already have solar panels and do you still have an analogue meter and the reversing counter system? Then the counter will run backwards if you generate more energy than you consume and forward if you consume more electricity than you generate.

Dilemma: “The capacity rate has been introduced and I don’t have a digital meter yet. Should I have it installed earlier or not?”

Both pitched and flat roofs are suitable for solar panels. For both types of roofs, they must be shade-free, sufficiently large and in good condition. Solar panels weigh about 10 kg/m². The structure of your roof must therefore be sufficiently strong. Your roofing is also best not too old and should certainly not contain asbestos.

For a sloping roof you should count on at least 1.6 m² per panel and for a flat roof on at least 2.5 m² per panel to avoid that the solar panels end up in each other’s shadow. A flat roof has the additional advantage that you can place the panels in the right direction and at the desired angle of inclination (ideally 30 to 45 degrees).

Solar panels facing south provide the highest efficiency, because they point directly at the sun when it shines strongest. This way you have a lot of generated energy around noon. But that doesn’t mean your solar panels should always face south. With a setup to the southeast or southwest, the efficiency loss is barely 5 percent.

Other orientations can also be interesting. If your solar panels are oriented to the east or west, they generate energy more evenly and you also have solar energy in the late afternoon or early evening when you return from work.

You can only estimate how many solar panels to install if you know your consumption. You can find your consumption of the past year on your settlement invoice. Don’t know your usage? Then keep in mind that an average family with two children uses about 3,500 kWh per year.

Are you planning to heat your home with a heat pump or to drive electrically? Then also charge for that extra electricity consumption. With a heat pump, your annual consumption increases by about 2,500 kWh, and for an electric car you have to count on a consumption of 3,000 kWh if you cover an average of 15,000 km per year.

also look at: With this handy overview determine how many solar panels you need.

Please note: the size of a PV installation is not expressed in kilowatt hours (kWh), but in watt peak (WP). To convert from Wp to kWh, divide the estimated electricity consumption by the conversion factor. In Belgium, this is about 1 with a southern orientation and rather 0.85 with an east-west orientation. This is how you calculate the minimum power you need.

The price of solar panels depends on the quality, the yield and the number of panels you have installed. The average price fluctuates between 1.1 euros and 1.4 euros per WP (excl. VAT). For an average consumption of 3,500 kWh, you need an installation with a capacity of 4,000 WP. The price is about 4,800 euros excluding VAT.

You pay 21% VAT on solar panels, unless your home is older than 10 years. Then you pay 6% VAT. Valid until December 31, 2023 the VAT reduction also applies to homes less than 10 years old. With this measure, the government wants to encourage families to switch to sustainable energy.

Solar panels are a smart investment, but how quickly do you earn them back? That depends on several factors. In the first place, your energy consumption, the current energy price and the injection fee play a role. A few years ago, the average payback time for solar panels was still ten years, while at the peak of high energy prices in September 2022, the average payback time was only 2.5 years.

Due to the strong price fluctuations, it is therefore difficult to predict how quickly you will earn back your solar panels. What is certain is that you will amply recoup your investment before the lifespan of the solar panels has expired.

Ter info: you can until the end of 2024 apply for a premium for solar panels.

The lifespan of a solar panel installation is on average 30 years. Over time, there will be a loss of efficiency. Exactly how much that is is difficult to detect, but you can assume an average return loss of 0.3% per year.

An inverter lasts about ten to fifteen years. Many manufacturers give a five or ten year warranty, but that doesn’t mean you have to replace it after that period. After twenty years, the inverter will have had its day, as the cables are subject to erosion by sun and water.

Do you want to store the electricity you generate with your solar panels? Then you can with a home battery. This way you can use the electricity with which the battery is charged during the day.

In addition, a home battery can also draw power from the grid during off-peak hours. This way you store cheaper electricity to use in the evening during peak hours. For the time being, home batteries are still relatively expensive to purchase and cannot be earned back quickly.

No budget (yet) to buy solar panels? You can also rent them

You can offer the yield of your solar panels – cheaply – to family or friends: this is how energy sharing works

Want to be sure of an optimal return? Then maintain your solar panels in this way