In this article we will analyze what happens if the grid and electricity fails and if our system can provide us with electricity.
Photovoltaic and lack of electricity in the network. Will the photovoltaic installation provide us with electricity in the event of a grid failure?
When installing a photovoltaic installation, investors often think of becoming independent from the energy company and significantly reducing electricity bills; of course this is correct. However, if the PV system is installed on a networked system (connected to the mains), then in case of a power outage due to a power failure or work in service of the energy company, our house is without energy. despite having a photovoltaic installation. Why is this happening and is there a way to avoid it? It is true that network failures and deliberate power outages due to service work are extremely rare in Poland, but not everyone wants, and not everyone can afford, power outages, especially when they have invested in their own source of electricity. , give it energy. independence.
Operation of the photovoltaic installation during a power outage
Photovoltaic installations during a grid failure, for example as a result of a power line interruption or during scheduled service work on the power grid, in most cases in Poland cannot supply us with electricity, although photovoltaic panels they can still produce this electricity. Why “in most cases” and not all? Well, in Poland, most of the installed installations are network systems that are connected to the grid through an inverter, in which, according to Polish regulations, the so – called anti-island protection, which turns off the inverter when the power supply to the electrical network is cut off.
Isolated or hybrid installation as a solution to the problem of power outages?
We already know that the lack of electricity in the home during a grid failure and with a photovoltaic system connected to the grid is inevitable and will occur in most cases of photovoltaic installations in Poland, if such circumstances occur. However, you can protect yourself against it, and two solutions will work in this case: an off-grid system or a hybrid system. However, they have, like everything else, their advantages and disadvantages. Which solution for our photovoltaic should I choose? It all depends on our needs, the possible problems of access to the electrical network and, of course, the wealth of the pocket.
In the case of an isolated system, the operation of the photovoltaic installation is 100% independent of the electrical network, in a closed system or the so-called island. The electricity produced in such a system is used immediately by devices in the home or, in the event that production exceeds demand, the excess is sent to special batteries, the so-called energy storage, from which it can be taken if it is necessary. It is thanks to energy storage that it is possible to maintain the continuity of the electricity supply, regardless of the weather or any failure in the power distribution network.
It should be noted that the off-grid system is mainly used in areas where access to the electricity grid is very limited. In Poland, such systems are most often used in summer cottages. If there are no problems with access to the grid in the location of the photovoltaic installation, it is recommended to install it in a system connected to the grid, since an off-grid installation usually generates some losses of generated energy: in summer, photovoltaic panels. it can produce such an amount of electricity that warehouses cannot fit. Surpluses are lost, while in the grid-connected system they are sent to the grid, from where most of them can be collected, especially in winter, when the solar panels do not produce enough energy and it is necessary to use the electricity from the net. . Also,
The installation of photovoltaic installations in a hybrid system is a combination of the characteristics of on-grid and off-grid systems: the hybrid system is connected to the grid and uses the possibilities of photovoltaic batteries, therefore, when it is cut off power supply. Outside the distributor, we can use previously accumulated resources. To create such a photovoltaic hybrid, you must install a hybrid inverter or two inverters: grid and island. And although unfortunately it is an important investment, taking into account the considerable costs of the components, the problem of “photovoltaics and the lack of electricity in the network” (on-grid) and the problem of losses of surplus produced ( off-grid) Cease to exist
How does such a hybrid work? In the morning, with a small amount of electricity sent from the panels, the devices in the house use electricity directly from the panels and from the grid. In the midday hours, the photovoltaic panels produce much more energy, the surplus of which goes to the batteries, and when they are charged, the surplus produced is sent to the grid (without generating losses). In the evening and at night, when the photovoltaic efficiency decreases, the household appliances run on batteries and only when the energy storage runs out of electricity is it drawn from the grid.