Renaissance Pravda Business Center. St. Petersburg, Russian Federation
ArchitectureThe Pravda project building, located near the St. Petersburg city center, is one of the first instances of green building design and construction approaches in Russia and is the first LEED certified commercial office building in the country. The story of the buildings starts in 1934 when it was built as local offices for the famous Pravda newspaper of the Soviet Union. When the newspaper ceased being published in 1990s, the building went on being used as warehouses, until the site was re-developed as a modern A class office building with 29.000 m2 gross floor area by Renaissance Development in 2009. The re-development plans are based on the conservation of the historical facade of the building, which is put in a delicate balance with curtain wall facade of the new floors through careful design.
Situated on a 75 m. x 75 m. site, the Pravda building has 2 basement floors and 8 above ground floors. The ground floor consists of a 4 storey high atrium, administrative offices, fitness room and dining areas. Remaining above ground floors house exclusively circulation areas and leasable office space in differing configurations. The two basement floors serve as underground parking and technical equipment space. The necessity of not preventing daylight access for neighboring Russia's First buildings results in a site plan with interior courtyards along with increasing facade setbacks with each successive floor. The different floor plans and varied configuration of leasable office space brings diversity to the facade, with street facing facades having high glazing ratios while inner facades have smaller windows. Windows between historical columns and doors to balconies are utilised with adherence to their original location and dimensions, while a large slanted skylight is located on the top floor facing north.
The office areas features operable windows to allow natural ventilation and thermal comfort independent from mechanical conditioning systems when desired by the occupants.
Size and location of operable windows have been designed in compliance with relevant LEED criteria. High performance double glazing with low-e coating and 18 mm. argon gap are featured on all windows.
Connected to the district heating system in St. Petersburg for all of its heating energy, the Pravda project building provides heating mainly through floor convectors installed by the contractor.
VRF systems for cooling provide flexibility for tenants through the ability to connect various indoor units configurations to the set of outdoor units located on the roof, and in addition allow supplemental heating through heat pump operation. Air cooled VRF systems provide high cooling energy efficiency in all spaces including the main entrance lobby as a result of high COP values and variable refrigerant flow.
Ventilation air is provided with 100 % outdoor air handling units with wheel type heat recovery and single coil for hot water.
The building energy model developed during building design and LEED certification phases also allowed the project team to evaluate operational strategies to minimize energy consumption.
While the district heating connection is a major factor in primary energy and carbon emission reduction, additional energy saving approaches implemented within the project boundary regarding air handling units, circulation pumps and automation system coupled with state-of-the-art equipment efficiencies put expectations of the energy consumption of the Pravda building to be approximately 35 % lower than similar buildings built to standard specifications.
Energy peformance assessment for LEED is carried out through comparison of the planned building energy performance to the “performance” of a reference building in compliance with methodology given in Appendix G of the ASHRAE 90.1 standard.
The reference buildings in St. Petersburg (ASHRAE Climate Zone 6A) are defined through, for instance, maximum building envelope facade U values, presence of economizer or heat recovery operation in air handling units or glazing shading coefficients.
Regardless of the climate zone, additional parameters regarding mechanical and lighting efficiencies are defined for the reference building in the ASHRAE standard. The Pravda project building has been able to achieve a high energy performance rating due to the improved parameters in these areas in addition to architectural energy saving features. Both planned as well as reference building energy models were developed with eQuest software using the DOE 2.2 energy simulation engine. Window performance values were calculated in compliance with NFRC standards with WINDOW v6.3 software. Curves representing capacity and efficiency under partial load for the VRF systems were as well as fan performance curves for all supply and exhaust fans were requested from the manufacturers and integrated into the energy model. Both models utilized hourly weather data published by ASHRAE that have been gathered from local meteorological stations over the past 30 years. The weather data includes many parameters including drybulb and wetbulb temperatures, direct and diffuse solar radiation, cloud cover, wind speed and direction. The surrounding buildings in this dense city area were also modeled so that shading effects from these throughout the day are taken into account.
The same planned building model created with eQuest was utilized for thermal comfort assessment taking advantage of the hourly reporting feature of the software. This allowed the green building consultants in the project to evaluate whether thermal comfort inside occupied areas were in line with anticipated conditions and at what frequency uncomfortable situations might arise depending on the climate features. Since LEED awards points for compliance with thermal comfort critera in ASHRAE 55 standard, design of mechanical systems used this standard as a basis of design along with local SNIP norms.
While some spaces with high activity rates (ie. fitness rooms) were outside the scope of the standard, alternative methods for developed for such areas to ensure thermal comfort.
An energy monitoring system was specified in the Pravda building to confirm that anticipated energy savings are indeed achieved and to validate the energy model results. The system is also expected to allow identification of opportunities for higher energy efficiency during building operation.
A measurement and verification plan complying with International Performance Measurement and Verification Protocol was developed and integrated into building operating procedures.
During design and implementation phases, solutions to conflicts between ASHRAE standards and Russian SNIP norms had to be developed regarding building mechanical systems and other technologies. Since Pravda is the first LEED certified commercial office building in Russia, experience from this project and the partnership with the US
Green Building Council for the approval of local standards will provide valuable guidance for future projects.
Last, but not least, green landscape utilisation has been possible on terrace balconies and ground level, albeit in a limited fashion. Species that are frost resistant and that can survive on natural rainfall were selected, rendering any need for artificial irrigation obsolete.
Use of low flow water fixtures within the building results in an annual water consumption reduction of 40 % compared to international minimum standards.
A crucial factor in the LEED Gold certification of the project has been the involvement of LEED AP certified green building experts during design and construction phases. Further, all studies related to energy performance and thermal comfort were carried out by an ASHRAE certified Building Energy Modeling Professional, while an ASHRAE certified Commissioning Process Management Professional has supervised building system commissioning procedures.
The Pravda building has been certified LEED Gold with 70 points. Some criteria of the LEED Core and Shell rating system, while seen promising in the initial project phases, have not been pursued due to non-compliance with criteria definitions. For example, while existing building walls and decks were retained on site, the 5 point criteria regarding this was missed to the requirement of maximum ratio between between new construction gross area and retained gross area.
Solar energy systems as well as daylight sensors for automatic control of lighting were deemed infeasible due to the northerly location of St. Petersburg.●
