Directive 2018/844 takes an important step in the direction of intelligent buildings, in continuity with many actions that the European Union adopted in recent years. 

The directive amended the previous directives on the energy performance of buildings (2010/31/EU) and on energy efficiency (2012/27/EU), requiring that large non-residential buildings will be equipped with automation and control systems by 2025. The boundary to be considered as ”large buildings” is, in this case, the effective rated power of air conditioning systems (or combined air conditioning and ventilation systems) which must exceed 290 kW.

In the directive, the attention of the European Parliament and the Council has been focused on the energy benefits that the use of building automation and control brings. In fact, the European Union is aiming for a sustainable energy system by 2050 with the aim of decarbonising the building stock, which accounts for about 36% of all CO2 emissions. 

For this reason, automation and control systems must monitor, record and analyse the use of energy in buildings, allowing it to be adapted at all times. In order to reduce energy consumption, it is also recommended that efficiency losses be detected and that the person responsible for the building's facilities or management be timely informed. 

Finally, the use of ”open” systems is a key point. The systems are required to allow communication with installations and other equipment inside the building and to be interoperable with technologies, systems and devices of different manufacturers.

In a functional building, lighting plays a very important role; first and foremost, it must meet the basic visual requirements inside the building, ensure correct illumination of the workstations and avoid glare. Increasingly, however, lighting is also used to enhance the internal and external architectural features of the building. 

Light also has emotional and biological effects and is a determining factor for the well-being, mood and health of people. This is simply because light regulates the internal clock of human beings. HCL, Human Centric Lighting, starts from this point and puts people at the centre of the building's lighting project. The aim is to get as close as possible to the effects of natural light also in indoor environments, integrating it as needed with artificial light of appropriate intensity and colour. 

Translating the HCL principle into a real lighting system for a functional building is now possible and convenient, thanks to the availability of light sources adjustable in intensity and colour, such as the latest generation of LEDs, and control devices for building automation. In this way, artificial light supports the biological rhythm of those who spend the whole day inside buildings, improves their well-being and health and promotes concentration on the job.

Buildings constructed or renovated in accordance with the latest legal requirements offer considerable potential for increasing energy efficiency, but to fully exploit this potential it is necessary to optimise the operation of the various technical systems. Building automation systems provide for this.

According to the EN 15232 standard, during the design phase it is possible to evaluate the energy savings obtained by adopting increasing levels of automation and to place the building in one of the four energy efficiency classes defined: from A (more efficient) to D (less efficient). 

Class A: includes buildings with high energy performance, equipped with control and automation systems (BACS) and technical plant management (TBM) characterized by high levels of accuracy and completeness of automatic control.

The Italian Interministerial Decree of 26 June 2015 (known as the “Minimum Requirements” decree) brought about an important innovation, prescribing for non-residential buildings a minimum level of automation corresponding to Class B for the control, regulation and management of building and heating system technologies (BACS).

BIM stands for Building Information Modeling and indicates a methodology to optimize and better manage the phases of design and construction of a building. BIM is used to follow a working method that involves the generation of a building model that can also manage the data of the entire life cycle through multi-dimensional virtual models generated digitally by means of specific software.

Ekinex is ready for the BIM era. The BIM product library is available in Autodesk Revit® 2016/2019 format for download at www.ekinex.com. The ekinex BIM Content Creator software is a true advanced configurator of the product range that will be enriched in the future. 

The main benefit of adopting the BIM methodology is the 3D representation at the design stage, which speeds up processes, reduces delivery times and allows errors and inaccuracies to be detected earlier. The greater efficiency in the sharing of information and a more precise control on all the processes involved, also make it possible to contain costs and schedule in advance maintenance operations.

The BIM is a standard process for all buildings and is being integrated into European legislation following the transposition of Directive 2014/24/EU on public procurement, which requires its inclusion in the procurement procedures of the Member States. 

In Italy, the directive was transposed by Decree no. 560 of 1st December 2017, which established the procedures and time schedule for the gradual introduction of electronic modelling methods and tools for construction and infrastructure. The decree provides for the obligation to operate with the BIM methodology from January 1st, 2019 for works worth more than 100 million euros and then from 2019 to 2025 will be introduced in Italy the obligation for all contracts for new public works.

More information

• Directive 2014/24/EU of the European Parliament and of the Council of 26 February 2014 on public procurement

• Ministerial Decree number 560 of 01/12/2017 (Italy)

The high level of insulation and high-performance windows and doors used in new buildings or in buildings that have undergone major renovation to meet the energy efficiency requirements of Directive 91/2002/EC (and subsequent legislation) have greatly reduced heat losses to the outside, with very positive effects on energy efficiency.

At the same time, these actions have in fact made buildings airtight, bringing the topics of ventilation and air renewal in confined spaces back to the centre of attention. However, these are functions that may require a lot of energy for the operation of the fan groups and therefore require an advanced control: a simple time control is not fully satisfactory and can only be considered as a general consensus for the definition of the time scheduling of operation. To ensure high air quality and, at the same time, low energy consumption, it is advisable to measure one or more environmental parameters to automatically adjust the fresh air flow rate to be introduced into the rooms. This is the concept known as Demand Controlled Ventilation or DCV. 

Many environmental parameters are available in a building equipped with an ekinex automation system: e.g. temperature, relative humidity, CO2 or TVOC concentration, presence/absence of people from the room, date and time, operation of other bus functions, etc. Depending on the requirements, these parameters can be used individually or linked with logical functions. With this type of advanced control, the energy saving is twofold: the activation time of the fan groups is reduced and the fresh air flow rate to be treated, before introduction into the room, through heating, cooling, humidification and dehumidification.

Control based on CO2 or TVOC value?
The choice of the air renewal control parameter depends mainly on the intended use of the rooms. Where the variability in the occupancy rate is very high or unpredictable (such as in meeting rooms, classrooms or small commercial rooms) CO2 is the most used indicator because its concentration (measured in p.p.m. or parts per million) is directly related to human activity and, in particular, to breathing. Although CO2 is not harmful to human health (except in very high concentrations, but difficult to achieve), it has a direct impact on the ability to concentrate and productivity of the occupants. 

When, on the other hand, the number of people in the rooms is predictable and limited, the detection of volatile organic compounds (or VOCs), a set of organic chemicals continuously emitted by furniture, paints, cleaning solvents, adhesives or other synthetic materials due to their high volatility, may be more significant. The reference parameter then becomes the concentration of TVOC (Total Volatile Organic compound), generally measured in p.p.b. (parts per billion).

A few years ago, the Directive 2010/31/EU on the energy performance of buildings introduced the concept of nearly-zero energy building (nZEB). It also prescribed a road map: from 31 December 2018, new public buildings would be nZEB, while from 31 December 2020 the obligation would be extended to all new buildings.

What is meant by a nearly-zero energy building
The Directive defines it as ”...a building that has a very high energy performance, and should be covered to a very significant extent by energy from renewable sources, including
energy from renewable sources produced on-site or nearby”. On the one hand, therefore, the amount of energy used for the main functions of the building (heating, cooling, ventilation, hot water production and room lighting) must be reduced. On the other hand, larger use of renewable sources must be made and, in particular, those available near the building.

Which technologies for a nZEB building
For the construction of an nZEB building, a combination of technologies is used on a case-by-case basis, resulting not only from the availability of economic resources, but also from climatic and behavioural factors. Of course, passive technologies that affect the building envelope, such as insulation, high-performance windows and doors or the thermal inertia of the mass, are the basis. But active technologies are becoming increasingly important today, such as the use of sunlight for lighting and free gains for heating, free-cooling, renewable sources (photovoltaic, thermal solar, micro wind, biomass) or the recovery of efficiency of HVAC systems. All these technologies must work in an integrated and coordinated way and end-users must be informed about their efficiency and convenience: for this reason, in an nZEB building the role played by building automation is increasingly important.

The Ekinex EK-HU1-TP office module allows the complete management of the functions of an office room by means of a single KNX device. In order to meet the requirements of minimising the space required for installation devices inside electrical panels, a large number of control and signalling functions have been concentrated in a single, extremely compact device (8 modular units, 144 mm wide), which usually require the use of several products:

• heating, cooling and ventilation by means of fan-coil units;
• lighting (direct ON/OFF through the outputs);
• shading (motorised awnings or shutters);
• ON/OFF control of electrical appliances (by means of controlled sockets).

The device offers numerous possibilities of operation in combination with Ekinex KNX or traditional (non-bus) devices. Climate control, for example, can be combined with Ekinex thermostats and multisensors, with Ekinex pushbuttons equipped with temperature sensor and thermostat function, with Ekinex interfaces equipped with inputs for NTC sensors and thermostat function. Alternatively, an office module input can be configured to connect an NTC sensor and use the climate controller integrated in the device. This gives the system designer maximum flexibility to choose the technical solution best suited to the individual office room and type of end user. 

In tertiary buildings, systems must always carry out a complex set of functions such as heating, cooling, ventilation, humidification, dehumidification and air renewal. In doing so, they must take into account the season, the external and internal conditions, the individual preferences of the end-users and meet essential energy efficiency requirements.

To avoid the proliferation in the same environment of a series of different and often incompatible sensors and control devices, the EK-ET2-TP multisensor offers a double order of advantages. First, it is developed according to the open and interoperable KNX standard and can therefore communicate natively with the entire world of KNX products. Secondly, it combines the functions of a temperature, relative humidity and air quality sensor with those of a room thermostat and a threshold controller for humidity and CO2 concentration.

A large number and variety of functions and options, which would normally require a whole series of devices, are therefore concentrated in a single, extremely compact device - which only requires the connection of a two-wire bus cable. In addition, it offers a range of logic ports that allow you to combine a range of information made available by the various ekinex devices to realise a demand-controlled ventilation (DCV), while achieving at the same time high air quality and efficient energy use.

How many times in buildings do you see lights on or air conditioning in operation without people? There are cases in which the manual control of the loads alone is not sufficient. To avoid wasting energy and prolong the useful life of the equipment, it is also advisable to have an automatic control that detects the presence and/or movement of people. In the event of prolonged absence, the sensors switch off the loads with a settable delay, and when people return to the room they automatically switch them on again.

The sensors EK-Dx2-TP (ceiling-mounting) and EK-SM2-TP (wall-mounting) do exactly this. And they provide different delays depending on the function to be controlled. The lighting can be switched off immediately after people leave the room, while longer delays can be set for the air conditioning; in this case, the climatic comfort conditions remain unchanged during short absences. In the case of longer absences, the operating mode is attenuated, for example from comfort to standby.