December 9th 2020

Sava Business Centre, Belgrade

Sava Business Centre, Belgrade

Quiddita Ltd. used IES Virtual Environment (IESVE) to carry out LEED energy modelling which led to LEED Gold certification for the Sava Business Centre in Belgrade.

The Sava Business Center is a state of the art Class A office building comprising two 10-storey office towers, located in one of the most dynamically developing areas of Belgrade.

Quiddita Ltd. used IESVE to determine the energy consumption and possible savings for the business centre in order to achieve LEED Energy credits EA 2.1: Existing Building Commissioning – Investigation and Analysis, and EA 2.2: Existing Building Commissioning – Implementation.

To begin with Quiddita Ltd., alongside the buildings facilities team, conducted an Energy Audit in which they use the Energy Star Energy Plan Guidelines to direct the process and conduct a systematic inspection of the building's systems as well as energy and water consumption. The goal of the Energy Audit was to allow the facilities team to better understand its building's energy use, determine where cost-effective savings can be made and measure progress.

Once the team had identified a number of Energy and Cost Reduction Measures (ECRM’s), they used the IESVE to simulate, test and verify a number of scenarios, in order to recommend the measures which would have the best impact in terms of energy and cost savings. 

These included:

  • Changing the set point temperature for winter and summer season (comparison of existing heating consumption with Winter Temp setpoint of 22 degC and suggested new Winter Temp setpoint of 21 degC)
  • Installing branch 2- way ball valve on hydronic systems for heating with special rotary actuator while two results (comparison of existing heating consumption without cutting-off tenant during non-occupiable hours and simulated heating consumption after winter setpoint with tenants not operable 24/7 with cutting off)

Based on accurate IESVE simulations, the Quiddita team discovered that most savings could be achieved with combining the above two measures.

Other Energy Efficiency Measures simulated in IESVE included:

  • Installing freon heat exchanger in cooling circuit after chiller compressors to reduce dissipation of heat on condenser units. Simulation of Chiller water loop was modeled to obtain rejected heat from condenser units which can improve heating during shoulder season.
  • Installing motorized dampers in ducts with actuators connected with signal cables to BMS and comparison of scenarios when tenants are ON during unoccupied hours or OFF during unoccupied hours with increasing summer Temp setpoints of 1degC. 

If all the recommended ECRM’s were implemented, it was discovered that the project could achieve savings of 725,2 tonnes of carbon per year and around $250,000 in costs. 

“We found the capabilities of IESVE extremely useful for the carrying out the required simulations and energy analysis for this project. The inclusion of manufacturer data used for the heat exchanger in the ApacheHVAC application was particularly helpful. Other benefits of the software included having an exact climate database, including historical temperatures for 20 years, wind rose influence and similar, which is very useful for calculating natural ventilation (MacroFlo application), and gives great opportunity to simulate window leakage and influence of infiltration gains. 

Also, solar gains are very easy to export from IESVE simulations. The RadianceIES application is great for getting artificial, natural or combined lux levels and illumination to office spaces. Heating and Cooling sensible and total loads can be very precisely simulated in the ApacheSIM application, after implementing proper geometry, all thermophysical characteristics of the building, orientation, location, climate zone, etc.” 

Višnja Vušković Minić, Team Leader Architect & Dejan Danilovic, Energy Audit and Modeling Engineer, Quiddita Ltd.