Photovoltaic plant on the roof - is it worth it and why?
Photovoltaic plant on the roof (FEC) — 15 important questions and answers
In recent years, interest in photovoltaic systems in Bulgaria has grown exponentially. The roofs of homes, halls and commercial establishments are increasingly being converted into mini power stations, which generate their own current from the sun. The reason is simple: electricity prices are increasing, technologies are becoming more accessible, and the state and the EU promote energy independent and sustainable solutions.
But the logical question remains — is it really worth the investment in photovoltaic plant on the roof (FEC), or is it just another "green fad"? In the following lines, we will consider all the advantages in detail, cons and financial aspects of rooftop solar systems — so you can objectively assess whether this solution is right for you.
What is a rooftop solar plant??
Photovoltaic (PV) headquarters is a system, which converts solar energy into electricity through solar panels. When the panels are installed on the roof of a house, building or production hall, we are talking about a rooftop photovoltaic plant.
The system usually includes the following main components:
- Photovoltaic panels – capture solar energy; most often they are monocrystalline or polycrystalline.
- Inverter – converts direct current (DC), produced from the panels, in alternating current (AC), usable in the household.
- Assembly construction – fastens the panels to the roof at an optimal angle to the sun.
- Electricity meter / batteries / controllers - monitor and regulate the flow of energy.
The headquarters can be:
- For own consumption (on-grid or hybrid system).
- For selling excess energy to the electricity distribution network (possible for companies and legal entities).
- Fully autonomous (off-grid) – with batteries, suitable for remote properties without access to the power grid.
Why interest in solar systems is growing?
10–15 years ago, photovoltaics were considered an expensive indulgence, available only to large investors. Today the situation is completely different:
- The price of the panels has fallen by over 80% relative to 2010 y..
- Their efficiency is significantly higher — above 22% in the quality single crystal models.
- Legislation facilitates grid connection and net reporting (i.e. you sell excess electricity).
- The EU and Bulgaria finance installations through various programs for energy efficiency.
All this makes rooftop solar power plants more than just environmentally friendly, and an economically advantageous solution.
How much does a rooftop solar plant cost??
The price depends on several key factors:
- System power (kWp)
- Quality and brand of panels
- Roof type and mounting structure
- Using batteries or not
Average market values to 2025 y.. with:
| Type system | Average power | Approximate price (BGN) | Application |
| 3 kWp | 18-20 m² cover | 7,000 – 8,500 лв. | A small house, apartment |
| 5 kWp | 30 m² cover | 10,000 – 12,500 лв. | Average single-family house |
| 10 kWp | 55-60 m² covering | 18,000 – 22,000 лв. | A big house / business object |
| 30 kWp | 160- 180 m² of coverage | 50,000 – 65,000 лв. | Small production facility |
If you include storage batteries, price may increase by another 30-50%, but it gives you more independence and flexibility.
How much current can a photovoltaic system produce??
Bulgaria is one of the countries in Europe with the highest solar radiation – on average 1300-1600 kWh per sq.m per year, depending on the region. Under ideal conditions, 1 kWp of installed capacity produces about 1300–1500 kWh of electricity per year.
An example:
- 5 A kWp system can produce approx 7000 kWh per year, which often covers 90–100% of the needs of an average household.
Ако електроенергията струва средно 0.35 лв./kWh, това означава спестени 2,450 лв. годишно само от сметки за ток.
Възвръщаемост на инвестицията
Основно изчисление:
- Инвестиция: 12,000 лв.
- Годишно спестяване: ~2,400 лв.
- Възвръщаемост: ~5 години
След петата година, всичко което системата произвежда, е чист приход или спестяване. Като се има предвид, че животът на панелите е над 25 years, това означава над 20 years of profit after the initial payback period.
At the enterprise, who sell excess energy, ROI can fall even below 4 years, especially with good buyout contracts.
Main advantages of the photovoltaic plant
✅ 1. Energy independence
The biggest plus is, that you are no longer entirely dependent on the electricity distribution company. In crises, inflation or rising prices, your electricity remains free.
✅ 2. Reduced electricity costs
With a properly sized system, you can reduce your bills by 80-100%. If you have batteries, you can use the produced energy in the evening as well.
✅ 3. Long life and low maintenance
The panels have a 25-30 year warranty, and the inverters approx 10 years. Maintenance is reduced to periodic cleaning and inspection.
✅ 4. Environmental advantage
Photovoltaic systems do not pollute and reduce carbon emissions. One 5 kWp system saves approx 4 tons of CO₂ annually.
✅ 5. Increasing the value of the property
A home with a photovoltaic system is more attractive when selling or renting. Buyers value energy independence.
✅ 6. Possibility of subsidies and financing
In recent years, Bulgaria has been offering European programs and grants for households and businesses, which cover up to 50–70% of the investment.
Potential disadvantages and risks
No technology is without flaws. Here's what you should keep in mind:
❌ 1. High initial investment
Although prices are falling, the initial amount is substantial, especially if the system includes batteries.
❌ 2. Dependence on sunshine
Production drops in winter and on cloudy days. In the absence of batteries, the system draws current from the network.
❌ 3. Limited roof space
Not every roof is suitable - you need enough square meters, correct slope and south/southeast orientation.
❌ 4. Inverter wear
The inverter is usually replaced after 10–12 years, which is an expense of about BGN 2,000–3,000. for a standard system.
❌ 5. Not all banks finance easily
Some credit institutions are still wary of financing photovoltaic systems, but the trend is improving.
On-grid, off-grid or hybrid system — which one is right for you?
| Type system | Characteristic | Suitable for |
| On-grid | Connected to the mains; net accounting is used. | Households in towns and villages with permanent network access. |
| Off-grid | Fully autonomous; battery operated. | Remote areas, lodges, grid-free farms. |
| Hybrid | Combines mains and batteries. | Houses with variable consumption and the need for backup power. |
✅ Most popular for Bulgaria: on-grid system with the possibility of future addition of batteries.
Where is the most profitable to install?
България има благоприятни условия в почти всички региони, но южните части и равнинните райони са най-подходящи:
| Регион | Средна годишна продукция от 1 kWp |
| Югоизточна България (Бургас, Сливен, Ямбол) | ~1450 kWh |
| Южна България (Пловдив, Стара Загора, Хасково) | ~1400 kWh |
| Северна България (Русе, Svishtov, Варна) | ~1300 kWh |
| Планински райони | ~1200 kWh |
Дори при по-ниска радиация, the differences are not fatal — it just takes a slightly larger number of panels for the same effect.
What is needed, to build a photovoltaic plant on the roof?
- Inspection of the roof - strength, direction, slope, shadows available.
- Energy survey - the required power is calculated based on the annual consumption.
- Design and permits - for systems above 5 kWp usually requires a project and coordination with CEZ/EVN/ENERGO-PRO.
- Contract with component supplier and assembly company.
- Installation, tests and connecting to the network.
It is a good practice to choose a company with experience and warranty service, not "cheapest offer".
Tax and regulatory aspects in Bulgaria
- For households - you don't need to have a company, to produce electricity for own consumption.
- For sale electricity (over 30 kWp or with a purchase agreement) – a legal entity must be registered and energy regulations must be complied with.
- There is no VAT on the energy produced for personal use.
- Permitting procedures are increasingly simplified for systems under 10 kWp.
Batteries - the new revolution
While years ago, batteries were the weak link in photovoltaic systems, today, technology has developed tremendously.
Lithium-ion batteries allow:
- Storing excess energy during the day and using it in the evening.
- Uninterruptible power supply during power outages.
- Optimization of self-consumption - more energy remains for you, less is sold at a low rate.
Although expensive (about BGN 1000–1200. per kWh capacity), batteries significantly increase the efficiency and independence of the system.
Photovoltaics for business and industry
For companies, photovoltaic systems are becoming a strategic investment, not just in saving:
- They reduce energy consumption and production costs.
- Increase ESG indicators (environmental responsibility), important for partners and investors.
- They provide an opportunity for additional income by selling surplus.
- They help with energy resilience in times of crisis.
In Bulgaria, hundreds of enterprises are already installing 30–100 kWp systems on the roofs of their warehouses, often financed with European funds.
What real owners say
Survey among Bulgarian households, installed PV between 2020–2024, shows:
- 94% are satisfied with the investment.
- 89% have achieved real savings, close to what was promised.
- 82% they state, that the system paid off for under 6 years.
- 97% would recommend PV to friends.
The most common conclusion:
“The first year, you watch the counter tick down and you realize, that you made the right decision.”
The future of photovoltaic systems
Solar energy is no longer just an alternative – it is the backbone of the future energy system.
With the development of:
- more efficient panels (to 30%),
- cheaper batteries,
- smart grids and control systems,
expected to 2030 y.. over 40% of the roofs in Bulgaria to have some form of photovoltaic coating.
For individuals, this means:
- Lower installation cost;
- Shorter payback period;
- More financing and subsidy options.
Conclusion: Is a rooftop solar plant worth it??
The short answer is: yes, it's worth it—more than ever!
Today, the photovoltaic plant is not just an investment in economy, and in energy security, sustainability and future.
She:
- Reduces your bills dramatically;
- Increases property value;
- It ensures independence from the unpredictable energy market;
- Contributes to a cleaner environment.
With good installation and optimal use, payback is 4–6 years, and the life of the system over 25. It is one of the safest and most predictable investments, that you can do on your property today.