frequently asked questions
The most frequently asked questions
Renewable energy is very trendy. Photovoltaics and suitable storage systems are becoming increasingly popular. A photovoltaic system produces clean electricity over the long term without emitting noise, odors or particulate matter and thus makes a direct contribution to counteracting climate change. Photovoltaics can be used in a wide variety of ways and can be used by everyone.
Photovoltaic and solar thermal are two different types of solar energy technologies. Photovoltaic (PV) uses solar cells to convert sunlight directly into electrical energy. PV modules are installed on roofs or open spaces to generate electricity for buildings or the public grid. The generated energy can be used either for own consumption or for sale to the electricity supplier. Solar thermal, on the other hand, uses sunlight to generate heat. Here, solar panels are installed on roofs or open spaces to absorb sunlight and generate heat. This heat can then be used to heat water for heating and hot water or for other purposes such as process heat in industry. In summary, photovoltaic converts sunlight directly into electrical energy, while solar thermal uses sunlight to generate heat.
Photovoltaics stands for the direct conversion of sunlight into electrical energy through the use of solar cells. The word photovoltaic is composed of the Greek words “phos” (light) and “volt” (unit for electrical voltage). Photovoltaics is therefore often referred to as light electricity. The technology has experienced rapid development in recent years and is now one of the most important renewable energy sources to meet the world’s growing energy needs.
A solar cell is an electronic device capable of converting sunlight directly into electrical energy. The cell consists of a semiconductor material that is able to accept photons (particles of light) and release electrons, creating an electric field. When sunlight hits a solar cell, the photons are absorbed by the semiconductor material, releasing electrons. These electrons can then move in the solar cell’s electric field and flow through an external circuit to generate electrical energy. Solar cells are often connected to form photovoltaic modules in order to achieve higher electrical output. These modules can then be installed on rooftops or open spaces to generate solar power for self-consumption or for sale to the public grid. Solar cells are an important component of solar technology and have helped advance the use of solar energy as a renewable energy source. A solar cell is a thin, approximately 15 x 15 disc, usually made of silicon or some other material. Contact strips are attached to the front and back, which carry away the current generated by the sunlight in the cell. The silicon is made from quartz sand. Other crystalline and thin-film solar cells are far less common. Their combined market share is less than 10 percent.
The power specification stands for Watt peak and is a unit of measurement used in solar technology to describe the nominal power of photovoltaic modules. The rated power indicates how much electrical power a solar panel can generate under standardized test conditions. Watt peak refers to the maximum power that a photovoltaic module can produce under standard test conditions consisting of an irradiance of 1,000 W/m², a cell temperature of 25°C and an air mass of 1.5. This means that a 100 Wp solar module can generate 100 watts of electrical power under these conditions. The Wp specification is an important feature when selecting photovoltaic modules and helps to determine the energy production capacity of a solar system. The higher the Wp specification, the more electrical power a solar panel can generate and the more electricity the solar system can produce overall.
The amount of electricity that a photovoltaic (PV) system can generate depends on several factors, such as the size of the system, the number and power of the solar cells used, the amount of solar radiation, and the efficiency of the system.u003cbru003eA A typical PV system with an output of 1 kWp (kilowatt peak) can produce around 800 to 1,200 kWh (kilowatt hours) of electrical energy per year, depending on the site conditions. Accordingly, a larger system rated at 5 kWp can generate up to 6,000 kWh per year.u003cbru003eThe exact amount of electricity that a PV system can produce can also be affected by factors such as the orientation and tilt of the solar panels, as well as the degree of shading become. Therefore, it is important to consult a qualified solar technician or engineer when planning and installing a PV system to ensure optimal performance and efficiency.
The power generation of a photovoltaic system depends on the intensity of the sunlight hitting the solar cells. When the sky is cloudy, the intensity of the sunlight is reduced, which can lead to reduced power generation by the PV system. However, modern solar cells can also generate energy in diffuse light conditions, and some PV modules are specially optimized for operation under cloudy skies. Therefore, even when the sky is cloudy, a PV system will still produce a certain amount of electricity, although the electricity production may be lower compared to a sunny day. Some PV systems are equipped with monitoring systems that can display the electricity yield in real time. In this way, the system operator can monitor the performance and, if necessary, react by reducing power consumption or switching on additional power sources. Overall, even when the sky is cloudy, a PV system can be a valuable source of energy and help reduce the need for fossil fuels and accelerate the transition to renewable energy.
Photovoltaic technology is considered safe and durable. Most photovoltaic modules are guaranteed for at least 25 years and can actually last much longer. There are even reports of PV modules that have been in operation for over 40 years and are still generating electricity. The longevity of PV modules depends on the quality of the components used in manufacturing and the environmental conditions in which the modules operate. It is important that modules are properly installed and maintained to ensure maximum lifespan. As far as safety is concerned, there are no known health risks associated with the use of photovoltaic systems. PV systems do not produce harmful emissions or waste, making them an environmentally friendly source of energy. However, when it comes to electrical safety, it is important that PV systems are installed by qualified professionals and that they are regularly maintained to ensure they are working properly. Electrical protection devices such as surge protectors should also be integrated into the system to protect against surges. Overall, photovoltaic technology is a safe and long-lasting energy source that is increasingly being used to reduce the need for fossil fuels and accelerate the transition to renewable energy.
A photovoltaic system consists of several components that work together to convert sunlight into electrical energy. The most important components include: Solar cells: These are the heart of a PV system and convert the incident sunlight directly into electrical energy. PV modules: Several solar cells are combined to form a PV module. A typical PV module has an output of between 100 and 400 watts peak (Wp) and consists of a housing that protects the solar cells from the weather. Mounting system: A mounting system holds the PV modules on the roof or at another suitable location. There are different types of mounting systems depending on the type of roof or mounting surface. Inverter: An inverter converts the direct current generated by the PV modules into alternating current, which can be fed into the power grid or used directly. Electricity meter: An electricity meter measures the electricity produced by the PV system to record the amount of electricity fed into the electricity grid. Cables and Connections: Cables and connections connect the various components of the PV system together and transport the generated electricity to the inverter and the power grid. Protective devices: Protective devices such as overvoltage protection devices and residual current circuit breakers protect the PV system and the connected devices from damage caused by overvoltages and current fluctuations. Collectively, these components work together to form a PV array that converts sunlight into clean, renewable energy that can be used to power homes, businesses, and communities.
A solar inverter converts the direct current (DC) generated by the photovoltaic modules into alternating current (AC), which can be fed into the power grid or used directly. The conversion takes place in several steps: MPP tracker: First, the inverter optimizes the power of the PV modules by finding the so-called Maximum Power Point (MPP) at which the PV modules can generate the maximum power. There is also a so-called MPP tracker that monitors the output voltage of the PV modules and adjusts it if necessary in order to find the MPP. Rectifier: The direct current coming from the PV modules is converted into a rectified direct current in a rectifier. Filter: The rectified DC voltage is freed from interference signals in a filter. Inverter: The inverter now converts the rectified direct current into alternating current, which has the same frequency and voltage as the utility grid. The inverter also adjusts the voltage and current to ensure constant grid voltage, ensuring the grid operator has no trouble integrating the power into the grid. Grid monitoring: The inverter monitors the grid voltage and current and ensures that the PV system only feeds power into the grid when it is permitted and that the power is fed in at the correct voltage and frequency. Data Monitoring: Modern inverters are often equipped with a data monitoring function that monitors the performance of the PV array and records operational data such as electricity production and uptime. Overall, the inverter is a crucial part of a PV system as it converts the generated DC voltage into usable AC power and ensures that the power is fed into the power grid without affecting the grid.
If you’re interested in getting your own photovoltaic power supply but still have no idea where to start, here are some steps you can take: Do some research online about photovoltaic systems and their components to get a basic idea Develop an understanding of how they work and what needs to be considered during installation and maintenance. Read testimonials from other homeowners who have already installed a photovoltaic system to learn more about their experiences and recommendations. Assess your energy needs to determine how much electricity you need and how much space you have available for a photovoltaic system. Check the legal and regulatory requirements in your area, such as building permits, permits and connections to the power grid. Look for local installers and let them provide you with quotes and suggestions for installing a photovoltaic system. Compare the costs and benefits of different systems and installers to find the best option for your needs and budget. Opt for a photovoltaic system and have it installed by a certified installer. Overall, it is important to do thorough research and make an informed decision before investing in a photovoltaic system. With the right planning and installation, a photovoltaic system can be a sustainable and reliable source of energy for your home.
The cost of a photovoltaic system and storage system depends on various factors, such as the size of the system, the output, the brand of the components, the geographical location, the type of installation and the financing options. It is therefore difficult to give an exact price as each situation is unique. In general, however, it can be said that the costs for a photovoltaic system have fallen significantly in recent years, as the technology has been continuously improved and demand has increased. As a rule, you can expect costs of 1,000 to 1,800 euros per installed kilowatt. A typical system for a family home has an output of around 3 to 10 kilowatts and costs between 5,000 and 15,000 euros. Battery storage can entail additional costs, but it can also help to increase self-consumption of the electricity generated and improve independence from the electricity grid. Battery storage costs also depend on various factors such as size, capacity, brand and type of installation. As a rule, you can expect costs of 500 to 1,500 euros per installed kilowatt hour. It is important to note that the cost of a photovoltaic system and storage can often be reduced through various government subsidy programs and tax breaks. So, be sure to research the options available to make an informed decision.
Yes that is correct. The feed-in tariff for photovoltaic electricity that is fed into the public grid has fallen in many countries in recent years. In some cases, it can therefore be financially worthwhile to use as much of the generated electricity as possible yourself instead of feeding it into the grid and receiving a lower payment for it. The idea behind this is to increase so-called self-consumption, that is, the electricity generated directly to use in your own household. This can be supported by installing battery storage, which allows the electricity produced to be stored and consumed at a later time when the photovoltaic system is no longer producing as much electricity or when the electricity demand is higher than the current production. By own consumption, the need for electricity from the public grid can be reduced, which can lead to savings in electricity costs. In addition, greater self-sufficiency with renewable electricity helps reduce CO2 emissions and increases independence from energy suppliers is important to note, however, that self-consumption is not the best solution in all cases and that an informed decision based on individual factors, such as electricity demand, installation costs and local regulations.
Purchasing a power storage unit can be worthwhile if you operate or are planning a photovoltaic system and want to increase your own consumption. A power storage unit allows you to store the power you have generated yourself and use it at a later time when the photovoltaic system is not producing enough power or when the power demand is higher than the current production. This can help to reduce the need for electricity from the public grid and reduce dependence on energy suppliers. Investing in an electricity storage system can be particularly worthwhile if the feed-in tariff for photovoltaic electricity is low and electricity prices are high. In this case, it can make financial sense to use as much of the generated electricity as possible yourself instead of feeding it into the grid and only receiving a lower fee for it. Purchasing a storage battery can also make sense if you want to make your energy supply more independent, for example to be self-sufficient in emergencies or to reduce the environmental impact of electricity consumption. In any case, you should conduct a comprehensive analysis to determine whether energy storage makes economic and technical sense for you. Factors such as the size of the photovoltaic system, the storage capacity of the battery storage system, the costs of installation and maintenance and the available government subsidies must be taken into account.
Yes, as a rule, the combination of photovoltaic system and storage is all the more worthwhile the higher your power consumption. If you have large electricity consumers, such as a heat pump, an electric heater or an electric hot water storage tank, you can cover most of your electricity requirements yourself with the combination of a photovoltaic system and storage tank and thus reduce your electricity costs. By storing the electricity generated in a battery storage system, you can also use the electricity when the photovoltaic system is not producing enough electricity, for example in the evening hours or on cloudy days. This allows you to further reduce your power consumption from the public grid. If you have high power consumption, you can also reap the benefits of grid relief. Grid relief means that the use of photovoltaic systems and storage systems reduces the electricity demand from the public grid, which can relieve the electricity grid and avoid bottlenecks. However, it is important to note that the economics of the combination of photovoltaic system and storage depends on many factors, such as the size of the system, the capacity of the storage, installation costs and local regulations. A comprehensive analysis and advice from a specialist is therefore recommended.
Self-sufficiency, i.e. independence from the power grid, is usually a long-term goal that cannot always be fully achieved. The degree of self-sufficiency depends on various factors, such as the size of the photovoltaic system, the capacity of the storage system, the power consumption and the location. Typically, a photovoltaic system in combination with battery storage can help to increase self-consumption of self-generated electricity and thus also increase the degree of self-sufficiency. The larger the system and storage facility, the greater the degree of self-sufficiency. However, in most cases it is not possible to become completely self-sufficient, since the electricity requirement cannot always be covered by a photovoltaic system and battery storage alone. In the winter months in particular, when there is less solar radiation, it can be difficult to generate sufficient electricity from the photovoltaic system.
In order to achieve a good level of self-sufficiency, various aspects should be taken into account: Size of the photovoltaic system: A larger photovoltaic system produces more electricity and can therefore increase self-consumption. Battery storage capacity: A large battery storage can store excess electricity and provide it at a later time when the photovoltaic system is not generating enough electricity. Power consumption: By reducing power consumption, self-consumption can be increased. This means that energy-efficient devices should be purchased and that electricity should be used consciously. Power Requirements: It is important to plan and analyze power requirements in advance. The size of the photovoltaic system and the battery storage can then be determined on this basis. Location: The location of the photovoltaic system also plays a role. Factors such as orientation, inclination and shading should be taken into account to ensure optimal power generation. It is advisable to seek advice from a professional to determine the optimal configuration of the photovoltaic system and battery storage. Depending on the location and needs, the configuration of the system can vary in order to achieve a good level of self-sufficiency.
The storage tank can be installed in different locations depending on the conditions and requirements of the building and the power system. Here are some options: Utility Room: Having storage in the utility room offers the advantage of being easily accessible and serviceable. In the basement: Storage in the basement can be useful if there is not enough space in the utility room. It must be ensured that the memory is dry and protected from moisture. Garage: If the garage is close to the house connection, a storage tank can be installed here. Outdoor: If there is no suitable space in the house, the storage tank can be installed outdoors. However, attention should be paid to weatherproof cladding to protect the storage tank from the effects of wind and weather. It is important to install the storage in a location that is safe, accessible and as close as possible to the photovoltaic array and power consumption to minimize transmission losses. In addition, the memory must be protected from extreme temperatures and humidity to ensure maximum service life.
Yes, a photovoltaic system can generate green electricity all year round, even in winter or when the sky is cloudy. However, the amount of electricity generated depends on various factors, such as geographic location, the orientation and pitch of the roof, the size and performance of the photovoltaic system, and weather conditions. Although less electricity is produced in winter and when the sky is cloudy than on sunny days in summer, modern photovoltaic modules are able to generate electricity even in diffuse light conditions. In addition, the days in summer are longer than in winter, which means that more energy is generated in summer than in winter. In regions with a high proportion of renewable energies, it can happen that more electricity is generated than needed at certain times . This so-called oversupply can be compensated for by storage or by feeding it into the power grid.
As a rule, the electricity generated by your photovoltaic system flows directly into your home network and is used from there by the connected consumers (e.g. household appliances, lighting, etc.). If your photovoltaic system generates more electricity than is currently being consumed, the excess electricity flows into the public power grid. To see how much electricity you are using from your PV system, you can install an energy management system or use an electricity meter that sits between your home network and the power connection to the public grid. Such an electricity meter shows you how much electricity is currently being used from your PV system and how much is being fed into the public grid. Some inverters also have a display that shows the current power flow. There are also smart control systems that automatically ensure that the electricity generated by the PV system is used in the house before it is fed into the public grid. This increases the self-consumption and self-sufficiency of your PV system.
The power generation of a photovoltaic system depends on several factors, such as the size of the system, the orientation and inclination of the solar modules, the geographical location and the weather conditions. An average PV system in Germany with an output of 5 kWp produces between 4,000 and 5,000 kWh of electricity per year. A larger 10 kWp system can generate around 8,000 to 10,000 kWh of electricity per year, depending on location and conditions. However, it is important to note that electricity production may be lower during the winter months due to shorter periods of sunshine and poorer weather.
The size of the PV array needed to meet a household’s electricity needs depends on several factors, such as the average electricity consumption, the amount of roof space available for installing the solar panels, and the geographic location. In order to completely cover the electricity needs of a household, the PV system would have to generate the same amount of energy as the household consumes in a year. An average family in Germany consumes around 4,000 to 5,000 kWh of electricity per year. A 5kWp system installed on a roof with optimal orientation and slope can produce around 4,000 to 5,000kWh of electricity per year, depending on location and weather conditions. However, it is important to note that one PV system cannot usually meet all of a household’s electricity needs, as electricity production fluctuates and does not always correspond to electricity consumption. A combination with an electricity storage device and/or power purchase from the grid can help to use the self-generated electricity more effectively and reduce the power consumption from the grid.
The savings that can be achieved with a photovoltaic system depend on various factors, such as the size of the system, the electricity production, the electricity consumption, the electricity price and the regional conditions. In principle, a PV system can help to reduce electricity costs or even eliminate them entirely if enough electricity is produced and consumed by the customer. For example, if you have a 5 kWp PV system on the roof and produce around 4,000 kWh of electricity per year, you can save up to 1,200 euros per year at an average electricity price of 30 cents per kWh. However, it is important to note that the savings depend on various factors and can vary depending on the situation. It is therefore advisable to carry out an individual calculation in order to determine the savings and profitability of a PV system in each individual case.
The installation of a PV system should generally be carried out by a specialist company that has the relevant experience and qualifications. Installation typically begins with an on-site inspection and detailed planning of the system, including precise module placement, orientation and tilt, wiring and inverter.Then the modules are mounted on the roof or other suitable location Site installed and connected to each other and to the inverter. The inverter converts the generated direct current into alternating current, which can then be fed into the power grid or consumed directly. Once installed, the system must be commissioned and checked by a professional to ensure everything is working properly. Official approval is required in many countries before the system can be put into operation.
Monocrystalline and polycrystalline solar panels both belong to the family of crystalline solar panels, but differ in some important characteristics. Monocrystalline solar panels consist of a single layer of crystalline silicon grown from a single crystal. They are usually black or dark blue and have higher efficiency than polycrystalline modules. The higher efficiency means they can generate more electricity per square foot, making them ideal for applications where space is limited, such as on a rooftop. However, they are also more expensive than polycrystalline modules. Polycrystalline solar panels are made up of multiple silicon crystals bonded together and are bluer in color than monocrystalline panels. They are typically cheaper than monocrystalline panels and have lower efficiencies, meaning they take up more space to generate the same amount of electricity. However, they are well suited for applications where space is less limited, such as on a large property. Overall, the choice between monocrystalline and polycrystalline modules depends on the specific needs of the project, e.g. space requirements, budget and performance expectations.
A hybrid inverter is a special type of inverter capable of managing and optimizing a PV array and battery storage. Essentially, a hybrid inverter works like a regular inverter, converting the DC energy generated by the PV array into AC and feeding it into the power grid or delivering it directly to the consumer. The difference is that the hybrid inverter also integrates the battery storage into the system and controls the flow of energy between the PV system, the battery storage and the electricity grid. If the PV system produces more energy than the household or the battery needs, the excess electricity can be charged into the battery storage instead of being fed into the grid. If the demand for electricity is higher than the capacity of the PV system, the hybrid inverter can discharge the battery storage to meet the demand. In this way, a hybrid inverter can help to increase self-consumption of the electricity from the PV system, reduce dependence on the grid and minimize the use of more expensive grid electricity tariffs.
A feed-in inverter, also referred to as a grid inverter, converts the direct current generated by a photovoltaic system into alternating current and feeds it into the public power grid. Single phase inverters have only one phase while three phase inverters have three phases. So the difference is in the number of phases. Single-phase inverters are usually suitable for smaller PV systems as they are usually designed for a power of up to around 5 kWp. Three-phase inverters are often used for larger systems because they can process higher outputs from 5 kWp to several hundred kWp. In addition, three-phase inverters enable better power distribution to the three phases of the power grid and can thus achieve higher efficiency.
Yes, there are some requirements that a building must meet in order to be suitable for a photovoltaic system. Here are some key points: Roof orientation: A south orientation is best for a photovoltaic system as it receives the most solar energy. However, an orientation to the east or west can also be suitable for a PV system. Roof pitch: The ideal roof pitch for a photovoltaic system is between 20 and 30 degrees. However, deviations are possible. Shading: A photovoltaic system requires as little shading as possible, since this impairs electricity production. Trees, neighboring buildings or chimneys can reduce the yield of the system. Roof condition: The roof should be in good condition and provide sufficient load-bearing capacity for the installation of the PV modules. Permits: Depending on the location and type of facility, permits may be required. It is advisable to find out about the necessary permits in advance. Electrical connections: A photovoltaic system must be connected to the electricity grid. It should therefore be checked whether there is sufficient space for the connection. These points should be checked in advance to ensure that the building is suitable for a photovoltaic system.
A photovoltaic system is usually low-maintenance and causes only low operating and maintenance costs. The modules must be cleaned regularly to ensure maximum performance. The functionality of the inverters should also be checked at regular intervals. The cost of maintenance and cleaning depends on the size of the facility, but is usually very small compared to the savings from electricity generation. It is usually advisable to have a maintenance agreement with a specialist company to ensure optimal performance and smooth operation of the system.
Yes, it is usually possible to retrofit a storage system later if you have already installed a photovoltaic system. However, it is important to keep in mind that there may be additional storage and installation costs if the system was not designed for this from the start. In addition, one should also consider the possible effects on the feed-in tariff and the self-consumption regulations, as these can change over time. It is advisable to consult a specialist for this purpose.