Energy retrofit in public building of 7 floors covering more than 4000 sqm
Zagreb Chamber of Commerce
On the premises of the Administrative Building of the Croatian Chamber of Commerce at Roosvelt Square in Zagreb, a complete energy retrofitting was carried out.
The retrofitting was subsidized by the Environmental Protection and Energy Efficiency Fund in the amount of 40%.
The 7-storey building covers an area of 4,583 sqm and hosts 216 employees.
The complete energy retrofitting includes the carpentry, thermal insulation, HVAC systems refurbishment.
The old Robur system change in the heating and cooling system (with more than 15 years of operation) was made up of individual gas boilers and chillers (15 units).
Existing equipment has been replaced by high-performance Robur reversible Gas Absorption Heat Pumps for heating and cooling GAHP AR. The new system has been installed on the roof instead of the old one in a 'skid' design, consisting of three cascade modules.
Each cascade module consists of five units that are completely hydraulically and electrically connected to a common steel stand. As part of the system, an electronic module control panel, digital remote cascade control with complete fault diagnosis (DDC), water collectors, gas collectors have been installed.
There is also a 'skid' with a specially designed cooling air cooler (ACF60-00 TK) for all-year cooling of the climate chamber.
The total thermal performance of the gas absorption plant is 425 kW, and the total cooling efficiency is 255 kW.
The gas reversible absorption heat pumps have a 150% efficiency in heating mode, equivalent to the COP = 3.75 thermal multiplier with 33.3% energy from renewable sources (air).
Within the refurbishment, two local thermal substations have been dismantled, and the third existing thermal substation (in the basement) was turned into a technical room for the entire facility. The system is integrated with solar panels for the domestic hot water production for the restaurant. The project's goal was to reduce the consumption of primary energy sources, gas and electricity, but also reduce environmental impact, such as carbon dioxide emissions.
Expected total annual energy savings is equal to 768,043 kWh, while CO2 emissions have decreased by 224 t per year.
Credits Tehnokom (www.tehnokom.hr)