Solar or more precisely photovoltaic panels produce electricity from sunlight. For this, they use the photovoltaic phenomenon, in which a semiconductor material creates a direct current due to the impact of the sun’s rays. This is converted by an inverter into alternating current that can be used in ordinary electrical sockets.
The best conditions for electricity production occur when direct sunlight hits the panels perpendicularly. Of course, the panels also work at other times, but in poor lighting conditions, their full potential cannot be used. Therefore, during installation, it is necessary to choose a place where the sun’s rays fall for the longest part of the day.
At first glance, the most suitable place for placing solar panels in the home is the roof of the family house. However, they can also be placed on the roofs of garages, pergolas, apartment buildings and production halls, or even separately on any plot of land. In addition, solar panels can also work on a cottage or on the roof of a caravan.
It is generally stated that the year-round best lighting conditions in the Czech Republic can be achieved when the panels are tilted at an angle of 35 to 45 degrees on the south side of the house. However, this is not a condition, other methods of placement are also suitable, including installation on vertical walls, for example directly on the facade of the house or balcony railing. In some places, the tilt of the solar panels even changes depending on the season. Panel installation experts always provide the best advice on placement.
The most common solution for households remains the classic in the form of panels on the roof. However, before embarking on such an installation, there are a few things to consider. One of them is the condition of the roof. The panels can be installed on different substrates, but the roof must bear their weight. If the roof is not in the best condition, it is advisable to consider reconstruction first. In addition, of course, it is necessary to observe how and when the sun shines on the roof.
The efficiency of solar panels is reported to be approximately in the range of 15 to 17 percent. Simply put, it is the share that the panels can convert into electricity from the total amount of incoming solar energy. Under optimal light conditions and a temperature of around 25 degrees Celsius, a maximum of one thousand watts falls on a square meter of surface perpendicular to the sun’s rays in the Czech Republic. Manufacturers i scientists are continuously trying to develop panels with higher efficiencyare however limited by the laws of physics.
Photovoltaic panel performance it is given by the type of device and is given in units of Wp denoting watt-peak (nominal power of the solar panel in laboratory, i.e. ideal light conditions). Current panels easily reach 300 Wp and more. At the same time, panels with an output of 1 kWp (kilowatt-peak) produce approximately 1000 kWh (kilowatt-hours) of electricity per year.
Naturally, optimal conditions for electricity production do not prevail all year round, and in some periods the performance of the panels is significantly reduced. Nevertheless, there is a way to contribute to energy self-sufficiency as much as possible. It is the installation of batteries in which excess electrical energy is stored. This can be used when the panels do not produce enough, typically at night.
Compared to the panels available just a few years ago, the lifespan and overall durability of the panels has increased and is increasing. Today’s models can work for 35 years without problems, some manufacturers even state 40 years. However, a gradual reduction in performance must be expected. Manufacturers often provide a warranty of up to 25 years, during which the condition of the panels should not drop below 80 to 85 percent of their initial performance.
At first glance, it might seem that the higher the temperature, the more energy obtained from the sun, and thus the higher the efficiency of the solar panels. But the opposite is true. Solar panels are best suited to sunny weather and temperatures around the aforementioned 25 degrees. At significantly lower temperatures, a reduction in performance may occur. However, these are not dramatic changes, so there is no need to worry that the panels will not produce enough electricity.
Photovoltaic panels do not have to be used only for the production of electricity. Sets that heat water directly or from excess energy are often used. Alternatively, you can use photothermal panels, which are used exclusively for heating water and any heating and do not produce electricity.
Thanks to the heating of water with the help of solar energy, it is possible to significantly reduce operating costs, especially in the summer, in the winter a reduction in performance must be expected. Therefore, an electric boiler should not be missing in the household, for example, which will help with heating domestic water during the winter months.
Solar panels, which can work on the roof of a motorhome, or just serve to charge small appliances and electronic devices at home, are commonly available at electronics stores. Their price, depending on the performance and the manufacturer, starts at around four thousand crowns.
However, if the panels are to be used on the roof of a family house or similar building, it is necessary to call in an expert who will supply the panels and install them professionally.
The price for installing solar panels changes not only over time, but also depending on the supplier. For example, CEZ offers on its website solar system with water heating from 160 thousand crowns, systems with battery storage from 213 thousand. The state subsidy is already included in the prices. However, the client will only know the exact amount when the selected company prepares a customized price offer. The price is determined, among other things, by the normal consumption of the household, which determines how large a solar power plant will need to be installed.
Installing a photovoltaic system on a family home is a sustainable and state-supported decision – the government is even considering a tax cut. As part of the New Green Savings program, you can get a subsidy of up to 200,000 crowns.
The owner or builder of a single-family house can apply for a subsidy, before starting, during or even after the work is completed. Firms that deal with the installation of panels often help with the settlement of subsidies directly, because it is necessary to prepare a project before submitting an application. The grant is then applied for online AIS SFŽP CR. And how much money can be obtained from the state?
|Basic installation with a power of 2 kWp and a standard inverter||40 thousand CZK|
|Basic installation with a power of 2 kWp and a hybrid inverter||60 thousand CZK|
|Basic installation with a power of 2 kWp and an efficiently used heat pump||100 thousand CZK|
|For every 1 kWp of output beyond the basic installation (2 kWp)||10 thousand CZK|
|For 1 kWh of electric storage system with batteries||10 thousand CZK|
Spring New green savings
As part of the program, you can draw a subsidy, for example, to replace windows, insulate the house, build a green roof, purchase and install a heat pump, or build a system for efficient collection and subsequent use of rainwater. Contributions can also be combined with each other. You can determine the approximate amount of the subsidy yourself calculate in a clear calculator.