Desigo Energy efficient applications: AirOptiControl Application data sheet Building Technologies s
Desigo Energy efficient applications: AirOptiControl Application data sheet CM110745en_02 01.03.2012 Subject to technical change.
Content 1 Brief overview: AirOptiControl ..............................................................5 2 Basics.......................................................................................................5 2.1 Constant air flow rate ................................................................................6 2.2 Variable air flow rate (staged) ...................................................................6 2.3 Demand-controlled ventilation (modulating) ........................
1 Brief overview: AirOptiControl AirOptiControl is an application to optimize air volume flow reducing energy consumption by up to 50 % and offering, in this manner, an outstanding starting point for the highest level of energy efficient operation of ventilation and air conditioning plants for up to 10 rooms. At the same time, comfort control ensures that limit values are maintained for temperature, humidity and air quality.
2.1 Constant air flow rate The constant air flow rate is guaranteed with a single-stage fan, using a scheduler to switch on or off. The entire ventilation plant is typically switched on in the morning and then switched off at night. A ventilation plant with constant air flow rate generally serves just one room or zone. Figure 2-1 2.2 Variable air flow rate (staged) Variable air volume (VAV) is understood as a ventilation plant that serves multiple rooms (or zones).
2.4 AirOptiControl AirOptiControl takes it a step further with a new kind of control algorithm and improves the energy balance sheet in a sustainable manner while maintaining defined comfort conditions. The air flow rate to and from the rooms is controlled subject to the room temperature and air quality control circuit. Air handling units are modulated controlled based on room demand signals for operating mode, air volume flow, temperature and humidity.
3 AirOptiControl 3.1 Overview AirOptiControl minimizes the air volume flow required by the rooms to ventilation and air condition using the following coordination functions: – Temperature coordination: Supply air temperature is controlled dependent on room temperature demand.
3.2 The most important energy efficiency functions 3.2.1 Demand-dependent control of fans, volume flow coordination Advantages: – Reduces fan electricity use by up to 50 % – Less noise – Improved control response "Volume flow coordination" refers to the control of supply air and extract air fan speed dependent on air volume flow demand in the individual rooms.
Energy efficiency control VAV dampers and air handling plant are switched on and off in an energy efficient manner dependent on – Room temperature – Room humidity – and room air quality. The VAV dampers in the room are closed when the room control variables temperature, air quality and optional humidity achieve the switch off setpoints within the applicable comfort setpoint range. The air handling unit is switched off if the VAV dampers are closed for all rooms.
3.2.4 Demand-dependent control of supply air temperature, temperature coordination Benefit: – Reduce volume flow "Temperature coordination" refers to control of the supply air temperature dependent on room air quality demand in the individual rooms.
4 Energy savings Comprehensive trials on real plants under lab conditions and building simulations consistently indicate energy savings in the neighborhood of 50 %. Data in the comparison below in Table 4-1 using a benchmark solution corresponding to building type for a Swiss educational facility. Further, optimization of volume flow coordination was conducted as part of a comprehensive simulation study in cooperation with the Fraunhofer-Institut IIS/SCS in Nuremburg (Germany).
4.1.1 Maximum savings The greatest savings are always available under "AirOptiControl functionality 4 (AOC 4)". The figure below illustrates the savings available to the different types of energy. Figure 4-1 5 Advantages and customer benefits 5.
– Time and costs savings during the engineering, commissioning and occupancy phases as well as lower service costs thanks to tested applications and detailed documentation – Meets the highest energy class in EN15232 and increases the value of the plant as well as the potential resale value of the building Figure 4-2 6 Field of application The exceptional energy savings using AirOptiControl yield the most at partial load operation.
7 Amortization period The following table provides examples of amortization periods for modernizations. The amortization period is calculated from annual energy savings and investment.
8 Display Prepared plant images for the air handling unit as well as room or zone are available in Desigo Insight. 1 2 3 4 5 Figure 8-1: Overview of operating elements for the air handling unit and centralized functions.
9 System hardware The AirOptiControl application is released for installation on the PXC-100/200 automation stations. – for installation on the PXC-100/200 automation stations or – for distributed installation on PXC-100/200 automation stations and PXC3.. as part of TRA. 10 Field Devices No special requires are placed on field devices with regard to measuring precision, quality, etc. Siemens field devices should be used whenever possible.
12 Appendix 12.1 Benchmark 12.1.1 Display by energy cost savings [EUR/m2/year] Figure 12-1 12.1.
12.1.3 Display by cost savings [%] Figure 12-3 12.1.
12.2 Plant components The AirOptiControl application is modular in design with variants and options to adapt the application to the widest possible range of ventilation and air conditioning plants. In provides solid coverage of typical ranges on both the room as well as air handing unit side. Support and unsupported components using AirOptiControl: Components Air handling unit.
12.3 Installation topologies Interesting topologies are possible using the Desigo island bus extension module to reduce overall installation costs (e.g. cabling). The following figures display three types of installation. Centralized installation Decentralized installation per room Figure 12-5 Figure 12-6 Decentralized installation, grouping of rooms Key Figure 12-7 Figure 12-8 You can divide the topology by primary plant and rooms if two automation stations are required to implement the plant.
13 About this document Before using our products, it is important that you read the documents supplied with or ordered at the same time as the products (equipment, applications, tools etc.) carefully and in full. We assume that persons using our products and documents are authorized and properly trained and have the requisite technical knowledge to use our products as intended.
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