Positive energy building (or BEPOS): what is it?

At a time when the ecological and energy transition is becoming essential, the concept of positive energy buildings (or BEPOS) is becoming increasingly important in new building projects and the renovation of private and public buildings.

Designed to produce more energy than they consume, these intelligent buildings represent a major step towards energy efficiency and reducing our carbon footprint. 
In this article, we take a closer look at the concept of positive-energy buildings, their specific technical and regulatory features, and the decisive contribution IoT can make to meeting today's and tomorrow's energy and environmental challenges.

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What is a positive energy building?

A positive energy building (BEPOS) is a building capable of producing more energy than it consumes over an entire year. In practical terms, this means that thanks to advanced technical solutions such as photovoltaic panels or heat recovery systems, these buildings generate enough renewable energy to cover all their energy needs: heating, domestic hot water, lighting, ventilation, heating, air conditioning, etc. 
The main objective of a positive-energy building is to achieve maximum energy autonomy by drastically limiting energy losses and optimising each consumption. This is achieved through intelligent construction techniques, such as excellent thermal insulation and efficient energy equipment. As well as being self-sufficient, a BEPOS even feeds its surplus energy into the public networks, thereby making an active contribution to the collective energy transition.
In this way, positive-energy buildings embody a sustainable and responsible vision of housing and infrastructure, fully in line with an ecological and economic approach that is viable in the long term.

What is the BEPOS label?

The BEPOS label is an official certification awarded to buildings that meet strict energy performance criteria, guaranteeing that they produce more energy than they consume. Initiated as part of the energy transition objectives set by the French government, this label aims to encourage and promote environmentally-friendly and economically efficient construction methods.
Awarded by independent certified bodies after an in-depth audit, the BEPOS label assesses several key criteria, including overall energy performance, insulation quality, on-site renewable energy production and optimised management of energy resources. Today, this label is recognised as an essential benchmark in France, both for project owners and property developers, and for local authorities committed to an exemplary ecological approach.
Obtaining the BEPOS label not only guarantees the environmental and energy quality of the building, but also represents a major asset for investors and occupants in terms of energy savings, thermal comfort and property value enhancement.

Technical characteristics of a positive energy building

Positive energy buildings are based on a set of technical characteristics grouped into three main categories:

• Insulation and building envelope :
  
  • Reinforced thermal insulation
  • High-performance glazing
  • Treatment of thermal bridges
• Renewable energy production :
  
  • Installation of photovoltaic panels
  • Installation of micro wind turbines
  • Use of geothermal heat pumps
• Optimised energy management :
  
  
  • Double-flow ventilation with heat recovery
  • Intelligent energy management systems (IoT)
  • Real-time monitoring and continuous optimisation of energy consumption using platforms such as Kuzzle IoT.

What advantages do positive energy buildings offer?

Positive-energy buildings offer several tangible benefits, whether in economic or ecological terms, or terms of comfort for occupants.

• Economic benefits :
  
  
  • Significant reduction in energy bills.
  • Increased property value.
  • Eligible for specific financial and tax incentives.
• Environmental benefits:
  
  
  • Drastic reduction in greenhouse gas emissions.
  • Active contribution to the energy transition.
  • Reduced overall environmental impact through the use of renewable energies.
• Comfort and well-being :
  
  
  • Improved thermal comfort.
  • Optimum indoor air quality.
  • A healthy environment that promotes the health and well-being of occupants.

These multiple benefits make positive-energy buildings a popular solution in the current climate of urgency and the need to control energy costs.

Design and construction of a BEPOS building

The design and construction of a positive-energy building requires a comprehensive, integrated approach right from the initial phase of the project. Several key stages are essential to ensure the success of a BEPOS project:

• Design phase :
  
  • Precise definition of energy and environmental objectives
  • Rigorous site selection (orientation, solar exposure, climate)
  • Choice of ecological, high-performance materials
• Construction phase :
  
  • Strict application of thermal insulation standards and techniques
  • Installation of energy equipment and renewable energy production systems
  • Deployment of IoT sensors for real-time energy monitoring
• Operating and monitoring phase :
  
  • Continuous monitoring of energy performance via an IoT platform
  • Regular optimisation of installations to maintain initial performance levels
  • Raising occupants' awareness and helping them to use the building efficiently

This rigorous, proactive approach guarantees the sustainable energy performance of the positive-energy building, while maximising the long-term economic and ecological benefits.

Regulations and certification

The construction of positive energy buildings (or BEPOS) is governed by precise regulations to guarantee real energy performance and a significant contribution to reducing environmental impact.

In France, key regulations include:

• The Réglementation Environnementale 2020 (RE2020), which imposes strict requirements in terms of energy consumption, reduction of carbon emissions, and use of bio-sourced materials.

• The tertiary sector decree (also known as the Éco Énergie Tertiaire decree) requires buildings in the tertiary sector to progressively reduce their energy consumption, with a target reduction of 40% by 2030, 50% by 2040 and 60% by 2050 compared with a reference year.

• The BEPOS Effinergie label, which recognises buildings that significantly exceed the energy criteria set by current regulations.

These regulations and certifications ensure a coherent approach and recognise the efforts made to design responsible, energy-efficient and environmentally-friendly buildings.

Examples of positive energy buildings in France

France has several successful examples of positive energy buildings, providing tangible proof of the effectiveness of the BEPOS approach:

• Tour Elithis Danube (Strasbourg): This 16-storey residential tower, built by Elithis, is designed to produce more energy than it consumes thanks to an innovative combination of reinforced insulation, photovoltaic panels integrated into the façade and IoT-controlled energy management.

• Lycée Kyoto (Poitiers): The first positive-energy high school in France, this school uses bioclimatic architecture combined with innovative systems such as photovoltaic panels, dual-flow ventilation and intelligent energy management.

• Woopa building (Lyon): An exemplary tertiary building, the Woopa combines energy performance and user comfort thanks to excellent thermal insulation, automated management of energy equipment and renewable energy production provided in particular by photovoltaic panels installed on its roof.

These concrete examples perfectly illustrate the feasibility and multiple benefits of the BEPOS approach in a variety of contexts, both residential and tertiary.

What cutting-edge technologies are essential for a positive energy building? 

To achieve its energy performance targets, a positive energy building must incorporate innovative technologies. Among these, the Internet of Things (IoT) plays a central role, enabling intelligent, automated and optimised management of energy resources. Here are the main technologies that are essential:

• IoT energy management solutions:

  • Deployment of sensors to connect equipment to retrieve energy consumption data

  • Use of an IoT platform to display data from connected energy systems in real time

  • Automation and remote control of equipment to optimise the use of energy resources. 

• Advanced renewable energy production equipment :

  • High-efficiency photovoltaic panels

  • Micro-wind turbines adapted to the urban environment

  • New-generation heat pumps using local renewable energy sources

• Intelligent energy storage systems :

  • Connected batteries to store and redistribute the energy produced

  • Predictive management solutions to balance production and consumption

These advanced technologies, including IoT, are key to ensuring the energy efficiency and sustainability of energy-positive buildings, while giving property managers and occupants precise, responsive control over their energy resources.

The benefits of IoT for energy-positive buildings 

The Internet of Things (IoT) offers decisive advantages for the performance of energy-positive buildings, particularly by optimising energy management and efficiency:

• Real-time control :

• Precise and immediate monitoring of energy consumption

• Rapid detection of anomalies for proactive intervention

• Data visualisation and integration :

• Aggregation and global visualisation of data from connected devices

• Seamless integration of data from external business systems such as Linky or GRDF meters

• Customised dashboards for in-depth analysis and rapid decision-making

• Energy optimisation :

• Automatic adjustment of energy systems according to actual needs

• Preventive analysis to anticipate and reduce unnecessary consumption

• Intelligent, proactive maintenance :

• Rapid identification of potential malfunctions or breakdowns

• Reduced operating costs thanks to better-targeted, proactive maintenance

Kuzzle's IoT platform provides property managers with a comprehensive, real-time view of their energy installations, promoting informed decision-making and sustainable energy performance.

What is the environmental impact of an energy-positive building?

The environmental impact of positive-energy buildings is considerably reduced compared with conventional buildings, thanks in particular to their low energy consumption and their ability to produce their renewable energy. Here are the main environmental benefits:

• Reducing greenhouse gas emissions:

  • Significant reduction in CO2 emissions thanks to the use of renewable energies

  • Direct contribution to the fight against global warming

• Reduced consumption of fossil fuels:

  • Reduced dependence on non-renewable resources (gas, oil)

  • Making the most of clean energy sources such as solar and wind power

• Reducing waste and using sustainable materials:

  • Choice of ecological, recyclable and bio-sourced materials

  • Reduction of site waste and better management of resources

So adopting the BEPOS approach is an effective and sustainable response to today's environmental challenges, making an active contribution to preserving natural resources and protecting the environment.

What is the difference between a positive energy building and a stand-alone building?

Although both concepts aim for responsible, optimised energy management, the positive energy building and the autonomous building differ significantly in terms of objectives and operation:

Positive energy building (BEPOS):

• Produces more energy than it consumes, to feed this surplus into the public networks.
• Remains connected to the energy grid to manage surpluses and occasional needs.
  Aims to make an active contribution to the global energy transition.
• Examples of applications: multi-family residential buildings, tertiary buildings (offices, schools, hospitals), individual dwellings in urban or suburban areas.

Autonomous building:

• Seeks above all complete independence from public networks.
• Designed to meet all its own energy needs without any external input.
• Often requires substantial energy storage systems to manage variations in consumption and production.
• Examples of applications: isolated homes or homes in rural areas with no connection to the grid, mountain huts, temporary or mobile installations.

In short, while the BEPOS is designed to produce an energy surplus that benefits the whole community, the autonomous building favours total independence in terms of energy resources.

Key facts

Positive energy buildings (BEPOS) represent a powerful lever for responding effectively to today's environmental and energy challenges. To achieve and maintain their exceptional performance, the integration of IoT solutions is essential. Thanks to IoT, buildings are becoming intelligent, able to optimise their consumption, detect anomalies quickly and continually improve their performance.

Kuzzle's IoT platform offers a comprehensive, flexible and scalable solution for connecting, controlling and visualising all the data generated by positive-energy buildings. By facilitating centralised and intuitive management of energy resources, Kuzzle IoT actively supports the building industry in its drive towards a successful, sustainable and high-performance energy transition.

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