Energy management in tall buildings: the Sabancı Center case (Yüksek Binalarda Enerji Yönetimi; Sabancı Center Örneği)

Overview

The paper was presented at the VIII. National Installation Engineering Congress (TESKON 2007, Izmir) and appears in the proceedings book of the Chamber of Mechanical Engineers (MMO) (p. 851). The author, Eser Çizer, reports 14 years of energy management experience at Sabancı Center in Istanbul. The building is a mixed-use office tower that also houses the IT (bilgi işlem) centres of Akbank and Sabancı Telekom. The most instructive parts for data centres are the free-cooling experience.

The free cooling planned in the design could not initially be run because the bank's water-cooled mainframes were fed from the same primary circuit. It started only in 2001, after IT moved to air-cooled equipment. The system runs 24 hours a day from 15 October to 15 March, which allows the chillers to be switched off. Chilled water supplied to the IT centres was raised from 14 C to 16 C in 2001, then lowered to 13 C in 2005 and 12 C in 2006 as IT loads grew.

On UPS, experience showed that IT-centre UPSs should be independent of building-wide UPSs; oversized shared UPSs ran at low load and low efficiency. Replacing the UPSs was expected to save about 170,000 kWh per year with a payback of about 2.5 years. The paper is an early Turkish operator account of mixed-use buildings with embedded IT rooms. Because it rests on a single building and 2007 technology, the numbers are specific to that building and cannot be applied directly to today's equipment; yet the constraints created by shared circuits and shared UPSs can still be read as a valid design lesson.

Key points

1. Free cooling planned in the design could not run initially because water-cooled mainframes were fed from the same primary circuit; it started in 2001 after IT moved to air-cooled equipment.
2. Free cooling runs 24 h a day from 15 October to 15 March, allowing chillers to be switched off.
3. Chilled water to the IT centres was raised from 14 C to 16 C in 2001, then lowered to 13 C (2005) and 12 C (2006) as IT loads grew.
4. IT-centre UPSs should be independent of building-wide UPSs; oversized shared UPSs ran at low load and efficiency.
5. Replacing the UPSs was expected to save about 170,000 kWh/yr with a payback of about 2.5 years.
6. The source is an early Turkish operator account of mixed-use buildings with embedded IT rooms.
7. The values belong to a single building and 2007 technology.

Using it in design

• Warn when IT and comfort loads share one UPS or one chilled-water primary loop, since that blocks independent temperature reset and free cooling.
• Model UPS efficiency at actual (not nameplate) load and highlight low-load operation.
• In mixed-use buildings, treat IT room cooling as a secondary loop or independent system separate from the main cooling loop.
• Keep the IT chilled-water setpoint as a design parameter that can be reset as load grows.
• For UPS renewal in existing buildings, run an energy-saving and payback analysis based on the load profile.

Who should read it

Mechanical and electrical engineers and building energy managers who design or operate IT rooms inside mixed-use buildings.

Publication details

Authors

Eser Çizer

Publisher

TMMOB Makina Mühendisleri Odası (MMO)

Year

2007

Document number

TESKON 2007 Bildiriler Kitabı, s. 851

Event

VIII. Ulusal Tesisat Mühendisliği Kongresi (TESKON 2007), İzmir

Document language

English

Source type

Industry body

Access

Free to read

Licence

Copyright retained; citation only — the publisher’s terms apply to the original document

Citation