How many solar panels for an 80 m2 house?

With the constant rise in electricity prices , it is becoming increasingly crucial to find alternatives to reduce your energy costs. Indeed, the cost of electricity has increased considerably in recent years and this trend does not seem to be reversing. For an 80 m² house, this can represent a significant part of the family budget.

This surface area of ​​the house generally involves the use of many electrical appliances : refrigerator, washing machine, dishwasher, television, computers, lighting, and sometimes even air conditioning or electric heating systems. All of these equipments, although necessary for daily comfort, consume a significant amount of energy.

Opting for solar panels for a house of this size has several advantages. First of all, a solar installation makes it possible to produce clean and renewable electricity , thus reducing dependence on traditional energy suppliers and mitigating the effects of price increases. Thanks to self-consumption , a house equipped with photovoltaic panels can cover a significant part of its energy needs , or even all of them if the installation is well sized.

Additionally, solar energy technologies have evolved considerably. Today’s photovoltaic solar panels are more efficient and durable , allowing you to maximize energy production even on a limited roof surface. By installing solar panels, you turn your roof into a mini power plant, contributing to solar energy production while reducing your electricity bills.

If you are interested in the subject, do not hesitate to go and consult how many solar panels for a 150m2 house .

The average energy consumption of an 80 m2 house

To fully understand the impact and benefits of a solar installation, it is essential to know the average energy consumption of an 80 m² house. This step is crucial to determine the number of solar panels needed and their profitability.

Average energy consumption

In France, the average energy expenditure of a house varies depending on several factors, such as the number of occupants, lifestyle habits, the energy efficiency of the house and the equipment used . For a house of 80 m², an annual electricity expenditure is generally estimated at between 7,000 and 10,000 kWh. Here is a typical breakdown of this expenditure:

• Electric heating : Approximately 50% of total expenditure, or between 3,500 and 5,000 kWh per year. This estimate may vary depending on the insulation of the house and the local climate.
• Domestic hot water : Around 15% of total expenditure, or between 1,000 and 1,500 kWh per year.
• Household appliances and lighting : About 35% of total expenditure, or between 2,500 and 3,500 kWh per year. This includes refrigerators, washing machines, dishwashers, ovens, televisions, computers, etc.

To learn more about a larger surface area, read our article on how many solar panels for a 200m2 house !

Factors influencing consumption

Several elements can influence the energy expenditure of an 80 m² house:

1. Insulation and energy efficiency : Proper insulation of walls, roof and windows can significantly reduce heating and cooling needs, thereby reducing electricity consumption.
2. Type of heating : Homes heated by electricity consume more than those using alternative heating systems, such as gas or wood.
3. Lifestyle habits : The number of occupants and their consumption habits (such as duration of showers, use of household appliances, etc.) have a significant impact.
4. Home appliances : Older, less efficient appliances typically use more energy. Opting for appliances that are rated “energy class A” or higher can make a big difference.

Why is this data important?

This information on average energy consumption is essential for correctly sizing a solar installation. By knowing your energy needs precisely, you can:

• Determine the power of solar panels required.
• Calculate the number of solar panels to install to cover part or all of your expense.
• Evaluate the profitability of your investment by taking into account the savings on your electricity bills.

For example, if your annual consumption is 8,000 kilowatt hours and you want to cover 100% of this consumption with solar energy, you will need to install a system capable of producing 8,000 kilowatt hours per year. Depending on the amount of sunshine in your region (which varies in France from 1,000 to 1,600 hours of sunshine per year), this represents an installation of 5 to 8 kWc.

With this data in hand, you'll be better prepared to take the next step: calculating how many solar panels you need for your 80 m² home.

How to calculate the number of solar panels needed?

Calculating the number of photovoltaic panels needed for an 80 m² house is essential to optimize your installation and maximize energy savings. Here's how to do it in detail.

Step 1: Determine annual electricity consumption

As mentioned earlier, the annual electricity expenditure of an 80 m² house is generally between 7,000 and 10,000 kilowatt hours . Let's take a median example to illustrate our calculation: suppose your house consumes 8,000 kilowatt hours per year.

Step 2: Estimate annual solar production

The production of a photovoltaic panel depends on several factors, including its power in kilowatt-peak (kWp) and the sunshine in the region. In France, sunshine varies between 1,000 and 1,600 hours of sunshine per year.

To estimate the annual production of a photovoltaic panel, we use the following formula: the annual production is equal to the power of the panel in kWp multiplied by the number of hours of sunshine. For example, a 1 kWp photovoltaic panel will produce between 1,000 and 1,600 kilowatt hours per year depending on the region.

Step 3: Calculate the number of panels needed

Now that we have the consumption and production data, we can calculate the number of solar panels needed. Let's say we install 300 watt-peak (Wp) panels, which is a common power for residential solar panels.

To cover an annual expenditure of 8,000 kilowatt hours in a region with an average sunshine of 1,300 hours per year, we must first calculate the annual production of a 300 Wp panel. This is done by multiplying the power of the panel (0.3 kWp) by the number of hours of sunshine (1,300 hours), which gives an annual production of 390 kWh per panel.

Then, to determine the number of panels needed, you have to divide the annual expenditure by the annual production of a panel. In our example, you would have to divide 8,000 kilowatt hours by 390 kilowatt hours per panel, which gives about 20.5. You would therefore need about 21 solar panels of 300 Wp to cover your annual expenditure of 8,000 kilowatt hours. In addition to these elements, you will have to take into account the efficiency of the solar panels as well as the profitability of the solar panels .

Step 4: Consider available space and technical constraints

It is essential to check whether the surface area of ​​your roof can accommodate the number of panels required. Each 300 Wp panel is generally around 1.6 m². For 21 panels, you will therefore need a total surface area of ​​around 34 m². Your roof must have this surface area, taking into account any obstacles such as chimneys or roof windows, and the slope of the roof to optimise exposure to the sun.

Step 5: Correction factors and system efficiency

It is important to include correction factors for things like roof orientation and pitch, potential shading, and system efficiency (which can be affected by temperature, dust, etc.). Typically, a 10-20% loss in efficiency is estimated due to these factors. So, it may be wise to add a few extra panels to compensate for these losses.

How many solar panels for an 80 m2 house?

Now that we have understood how to calculate the number of solar panels needed, it is time to answer the question precisely: how many photovoltaic panels do you need for an 80 m² house? Taking into account the various factors mentioned above, we can give a more concrete estimate.

Annual electricity consumption

As a reminder, an 80 m² house generally consumes between 7,000 and 10,000 kilowatt hours per year. For our example, we have taken an annual consumption of 8,000 kWh. This estimate may vary depending on consumption habits, the number of occupants, and the energy efficiency of the house.

Solar production

In France, a 1 kWp solar panel produces on average between 1,000 and 1,600 kilowatt hours per year depending on the region. For our calculation, we took an average of 1,300 kilowatt hours per year for a 1 kWp panel. Thus, a 300 Wp (0.3 kWp) panel would produce approximately 390 kilowatt hours per year.

Calculating the number of panels

To cover an annual consumption of 8,000 kilowatt hours with 300 Wp panels each producing 390 kilowatt hours per year, we need to divide the annual consumption by the annual production of one panel. So, by dividing 8,000 kWh by 390 kWh per panel, we find that approximately 21 solar panels are needed.

Checking available space

Each 300 Wc panel measures approximately 1.6 m². To install 21 panels , you must therefore multiply 21 panels by 1.6 m² per panel, which gives a total of 33.6 m². Your roof must therefore have a surface area of ​​approximately 34 m², taking into account any obstacles such as chimneys or roof windows, and the slope of the roof to optimize exposure to the sun.

Correction factors

It is also important to take into account correction factors related to the orientation and inclination of the roof , possible shading , and the efficiency of the system . In general, a loss of efficiency of 10 to 20% is considered due to these factors. To compensate for these losses, it may be wise to add a few additional panels. If we take into account a margin of 15% for losses, we will need approximately 24 panels instead of 21.

How profitable is a solar installation for an 80 m2 house?

Investing in a solar installation for an 80 m² house can offer significant financial benefits. Here is how to evaluate the profitability of this project by taking into account the costs, the savings made, and the aid available, highlighting the specific features of the plug and play solar kits offered by Oscaro Power.

Cost of installation

The average cost of a solar installation in France is generally between €1,500 and €2,500 per kilowatt-peak (kWp) installed. For an 80 m² house requiring around 24 solar panels of 300 watts-peak (Wp) each, the total power of the installation would be around 7.2 kWp (24 panels x 0.3 kWp). Thus, the total cost for an installation of this size would be between €10,800 and €18,000, depending on the equipment chosen and installation costs.

However, at Oscaro Power, we offer solar kits designed for self-installation, which means you can install the panels yourself without any additional installation costs. This significantly reduces the overall cost of the project.

Savings on electricity bills

To assess the savings, you need to compare the cost of electricity without solar panels with the costs after installation. In France, the average electricity rate is around €0.20 per kWh. If your home consumes 8,000 kWh per year, your electricity bill would be €1,600 per year without solar panels.

By installing solar panels that can cover 100% of your consumption , you could reduce your bill to zero , which represents an annual saving of €1,600. Over the lifetime of the solar panels, which is around 25 years, your total savings could reach around €40,000.

Profitability and return on investment

To determine profitability, it is important to calculate the time needed to amortize the initial investment. With Oscaro Power solar kits , which do not require professional installation costs, you save on the typical costs associated with solar installations.

If the average cost of your solar kit is €10,800, and you make annual savings of €1,600, the time needed to amortize this investment is calculated by dividing the total cost by the annual savings. So, you divide €10,800 by €1,600, which gives a depreciation time of approximately 6.75 years. But don't forget that if you install your solar kit yourself, it will cost you much less on Oscaro-Power.com! Don't hesitate to configure your kit online for free.

This amortization time could be even shorter depending on the promotions and discounts available with Oscaro Power solar kits. Once this time has elapsed, you fully benefit from the savings on your electricity bills, thus increasing the profitability of your investment.