About us

Company history

Key4S doo Belgrade was founded in 2014. in Belgrade. Our portfolio of services includes the design and construction of solar power plants, consulting services in the field of information technology, business and energy, as well as the development and maintenance of software solutions.

We are a partner to large and small companies, public and private institutions to which we provide professional services.

Our company employs professionals with many years of experience who deal with the development of complex projects and challenging solutions. Flexibility, efficiency and an individual approach to each client are the basic principles we follow in our work.

Our consultants and engineers have implemented a large number of development projects in the Ministry of Agriculture, Ministry of Justice, Ministry of State Administration, state administration and local self-government bodies.

Our team of consultants participated in business improvement projects in a large number of companies and banks in Serbia.

In the desire to provide our services to as wide a circle of users as possible in 2017, we expanded our business to the territory of the EU by establishing the company Key4s Global Consultig in Tallinn, Estonia.


We offer you tailor-made solutions, from individual solar panels to complete photovoltaic systems – solar power plants. Now in its 10th year, Key4s has continuously shaped the development of solar energy as a source of renewable energy.

We are one of the pioneers in Serbia in the field of solar technology and one of the international partners in the field of energy production from sunlight.

Key4S is a complete solar energy system provider that offers everything from consultation to maintenance under one roof. Whether building a solar power plant in the commercial sector, industrial sector, public sector or private households, Key4S can help you develop a customized, personalized concept that suits your needs and energy requirements, taking into account localized conditions.

Our mission is to provide an unparalleled experience tailored to our clients’ needs.

A vision

Distribution of solar energy to build a better world.

The company Key4s provides services for the construction of an ecologically clean and cost-effective solar power plant. Users of our services are households, public institutions, commercial and industrial customers. Od pojedinačnih solarnih modula do kompletnih solarnih parkova.

Distribution of solar energy by one of the most experienced teams in the field of solar solutions in Serbia.

How they work
our power plants?

  1. The panels can be attached to the roof or the ground.
  2. The sun generates solar energy.
  3. Solar panels collect solar energy and convert it into DC electricity.
  4. The solar panels are connected to the inverter.
  5. The inverter transforms the direct current from the panel into alternating current, which can be used on the grid.
  6. Electricity from the power plant can be used for:
    – own needs
    – network delivery/sales


Our business is guided by a strategy of sustainable development and continuous improvement that is in line with national and international standards, for which we have been awarded various certificates and marks.

As a testament to this commitment, Key4s has received confirmation from relevant certification bodies that our management systems, products, services and processes comply with applicable regulations, as well as national and international standards.