Photovoltaic with or without storage: which is more convenient?
If you are considering installing a photovoltaic system, you are not alone: according to the Italia Solare report, as of December 31, 2024, 1.878.780 photovoltaic systems were connected in Italy, for a total power of 37,08 GW. The increasingly important diffusion of this type of system is linked to an excellent combination of tangible benefits: autonomous production of green energy, savings on bills, reduction of environmental impact, increase in the value of your property, and more. If you have decided to focus on solar energy, an important question remains: is a photovoltaic system with storage or without better?
With the growing diffusion of storage systems, i.e. batteries that allow the storage of energy produced but not immediately used, more and more families and companies are wondering what is the most convenient, efficient and suitable solution for their needs.
Let’s look together at the costs, advantages, real savings on the bill and the differences between photovoltaic with and without batteries.
Photovoltaic with storage: what it is and how it works
Before understanding the differences between the two systems, let’s start with the definitions. A photovoltaic system with storage integrates the classic photovoltaic modules (commonly called solar panels) and inverter with a battery system, usually lithium, which allows you to store the energy produced but not immediately consumed during the hours of photovoltaic production, i.e. during the day, to be able to use it at a later time, when the user needs it most: in the evening, at night or at times when solar production is low.
By choosing storage, you can actually significantly increase your energy self-consumption and reduce the amount of energy taken from the grid, improving both the economic and ecological efficiency of the system.
How does photovoltaic with storage system work
The operation of this system is very simple. It all starts with photovoltaic panels installed on the roof or on a dedicated area. During daylight hours, solar radiation hits the panels causing the photovoltaic effect, which translates into direct current (DC). The inverter then intervenes, which transforms the direct current (DC) into alternating current (AC), which is the type of current used in most domestic and industrial applications. This is how electrical energy is generated!
This self-produced energy through photovoltaics has two possible destinations: it can be used immediately to power domestic or business consumption, or, if not used, it is stored in storage batteries in order to be used at another time.
The real strength of this system lies precisely in this last step: the unconsumed energy is not sold to the national grid, but is stored to be used at a later time, such as in the evening, at night or on cloudy days. This means that the system continues to supply energy even when the sun is not shining, without having to draw electricity from the grid, with consequent economic waste.
If, however, the photovoltaic energy production were to be sufficient to cover real-time consumption and at the same time recharge the storage batteries, the excess would be automatically released into the electricity grid: in this case, it would be subject to economic valorization through the mechanisms stipulated with the GSE (Energy Services Manager) such as the GSE Ritiro Dedicato.
What is a photovoltaic system without storage
The PV system without storage is the simplest and most traditional configuration among those available. It is a less complex system configuration than the previous one, which in fact applies only the essential devices to constitute a photovoltaic system: the photovoltaic panels and the inverter.
The operating principle is real-time: the electricity generated by the photovoltaic system is used in real time to satisfy (in part or in full based on the power of the system) the consumption needs or, where energy production exceeds the requirement, it is sold to the grid with associated economic valorization.
The real difference with photovoltaic with storage is that, in this case, the unused energy cannot be stored for deferred use.
Photovoltaic with or without storage: the differences
We have seen the characteristics of the photovoltaic system with and without storage. As you can imagine, choosing the type of system to invest in is one of the most important decisions to make when deciding to switch to solar energy.
We know that both solutions allow for the production of clean energy, but they differ in terms of how they are used, their economic benefits and their independence from the grid. Here is a breakdown of the differences.
Immediate Vs. deferred self-consumption
A photovoltaic system without storage allows you to consume energy only while it is being produced, typically during the day. Excess energy is fed into the grid. On the contrary, a system with storage allows you to store the energy produced during daylight hours and use it even in the evening or at times when the system does not generate electricity.
Energy independence from the grid
If you choose a system with storage, you can drastically reduce your dependence on the electricity grid, even during hours when there is no PV production. Without storage, however, drawing from the grid will remain an inevitable constant. This exposes the user more to fluctuations in the price of energy.
Initial cost
Another important difference between photovoltaic with or without storage has to do with prices: the system with batteries has a higher initial cost, given by the price of the storage system. It must be said, however, that the incentives available connected to the compensation given by the system itself make the investment sustainable today and with increasingly shorter payback times.
PV system with storage: when it is convenient
A photovoltaic system with storage is an advantageous choice in many situations, but it is not always the best choice. Relying on a qualified operator allows, in fact, to carry out an accurate preliminary technical analysis aimed at best balancing the investment.
For example, the analysis of historical energy consumption data will be essential in this initial phase, not only in terms of overall consumption but also for specific consumption bands and related peaks. The identification of the consumption time bands and the current energy tariffs will allow us to understand to what extent the system can contribute to energy savings, both for the share of self-consumed energy and with respect to the energy fed into the grid and withdrawn from it. This phase will allow us to quantitatively determine the resulting economic and technical choices, including the possible presence or absence of a storage system.
Simplifying the topic as much as possible through some examples, we could say that accumulation is recommended:
- Families whose energy consumption is prevalent in the evening or night hours, when the system does not produce energy. Examples: families with members who work during the day and return in the evening: the possibility of using the energy produced and stored during the day avoids drawing from the grid during time slots when sunlight is not available;
- If you have heat pumps, air conditioners or smart appliances that work at scheduled times, since batteries are a way to manage the electrical load with greater flexibility;
- In areas with frequent power outages: a storage system combined with a backup box can be a guarantee for an energy reserve useful for emergencies.
PV system without storage: when it is convenient
Although the system with storage is generally more efficient from the point of view of savings, systems without storage can also be interesting for families and businesses.
For example, the system without storage can be an optimal choice in houses populated mainly during the day or with families with small children, where household appliances are used mainly during the day, in conjunction with photovoltaic production.
We also remind you that with the Scambio sul Posto (within the expected terms) or Ritiro Dedicato, you will still be able to give value to the energy not self-consumed, selling it to the GSE, thus recovering a part of the investment.
Discover the most suitable system for you with Southenergy
Are you unsure about which system to choose, with or without storage? With Southenergy you can receive personalized advice to truly optimize your self-consumption and reduce your bills.
Make the most of the potential of photovoltaics: contact us to evaluate together the best solution for your home or business.
FAQ Photovoltaic with or without storage
What is the difference between a PV system with storage and one without?
A system without storage uses the energy produced for immediate consumption or for transferring energy to the grid in cases of excess consumption. A system with storage, on the other hand, has a battery that stores the excess energy produced, to be used at a later time (e.g. in the evening or on cloudy days).
What are the advantages of a storage system?
With a storage system you can:
- Increase self-consumption of energy produced;
- Further reduce bills;
- Have energy available even during a blackout (with specific systems);
- Improve the energy efficiency of your home.
When is it best to choose a storage system?
The storage system is convenient if:
- You consume a lot of energy in the evening or at night;
- You want to be less dependent on the electricity grid;
- You already have a PV system that produces more than you consume;
- The goal is to maximize long-term energy autonomy.
Does the storage system have any disadvantages?
Actually, no, except for the higher initial cost: the batteries significantly increase the price of the system. However, a mix of available incentives and compensation provided by the system itself make this “disadvantage” absolutely sustainable.
Which system is more convenient in economic terms?
In the short term, a system without storage is more convenient due to lower costs. However, in the medium-long term and on the basis of a correct preliminary energy diagnosis, a system with storage can become significantly more advantageous.