Solar panels can work throughout the year, but in winter their productivity decreases significantly. At the same time, even in the cold season, a solar station is capable of providing part of a household's needs if the equipment is selected correctly and batteries are provided for.
Ihor Liebiediev, commercial director of the company "Heneratsiia", which specializes in the design, sale and installation of solar power plants for private homes and businesses, told UNIAN about this in a comment
According to him, the main reasons for the decrease in winter generation are a shorter daylight period, the low position of the sun above the horizon and cloudiness. Cold itself is not a problem for solar panels: at the same level of solar radiation at a lower temperature, they can even work more efficiently.
As an example, the expert cited two design calculations of solar power plants for private houses in Odesa Oblast:
Thus, in the given examples, December generation is 77-85% lower than July generation. At the same time, these are forecast indicators for specific sites, and the actual output will depend on the region, orientation and tilt angle of the panels, shading and weather conditions.
"For backup power, it is important to take into account not the average monthly generation, but the ability to provide the house with electricity even during several cloudy days," Liebiediev explains.
A solar station can cover part of a household's needs even during a short daylight period. However, the panels alone are not enough for backup power.
An ordinary grid-connected solar power plant automatically switches off if electricity disappears in the external grid. In order for the house to continue receiving power, an appropriate system configuration is needed – in particular, an inverter with a backup function and storage batteries.
First of all, it is necessary to determine which appliances must work during outages. Usually these are lighting, a refrigerator, the internet, gas boiler automation, pumps and the necessary sockets. If the owner wants to ensure the operation of electric heating, a water heater, an electric stove and other powerful appliances, the requirements for the system increase significantly.
"Solar panels generate electricity, and batteries store it. In winter, generation may be insufficient for daily charge restoration, so it is necessary to provide for the possibility of charging from the grid, and during prolonged outages – an additional power source. The main task is not just to install more panels, but to correctly calculate the entire system for the needs of the house," the expert notes.
It is technically possible to increase winter output by installing additional panels. However, this will increase the cost of the system and may lead to significant electricity surpluses in summer.
If a person is interested in autonomous operation throughout the year, solar panels can be a successful solution, given the projected annual generation and possible savings. However, if there is a need to provide backup power right now, on the eve of winter, then one can start with an inverter and batteries, Liebiediev notes.
The battery capacity depends primarily on the power of the appliances that need to be powered and the duration of autonomous operation, the expert says. For example, if lighting, a refrigerator, the internet, boiler automation and other necessary appliances together consume an average of 0.5 kW, then over 8 hours they will need 4 kWh of electricity.
If we take into account that about 80% of the nominal battery capacity is available to consumers, the approximate autonomous operation time will be as follows:
According to Liebiediev's estimate, a basic backup power system for an apartment without solar panels can be set up from 2.5 thousand dollars, or approximately 114 thousand hryvnias at the estimated exchange rate of 45.5 hryvnias per dollar.
A hybrid solar power plant for a private house with panels with a capacity of 5.9 kW, a 6 kW inverter and a 5.12 kWh battery will cost from 270 thousand hryvnias turnkey. At the same time, a configuration with panels of 15.02 kW, a 15 kW inverter and a battery with a capacity of 16 kWh will cost approximately 520 thousand hryvnias turnkey.
The expert emphasizes that these are examples of specific configurations, not universal prices for all sites.
Earlier, UNIAN wrote about whether a solar panel installed on the balcony of a multi-storey building allows one to save on electricity bills.
It was also reported whether solar panels really need to be placed facing south. Yes, a study showed that under current electricity tariffs, another solution may turn out to be more advantageous.