Old Mutual Investment Group Property Investments - Energy Savings on HVAC Systems

Heating, ventilation and air conditioning (HVAC) systems are large consumers of power in commercial buildings such as shopping centres, hotels and office blocks. In fact, according to recent statistics, HVAC systems account for nearly 30% of the electricity consumed in the commercial sector during peak demand periods (7am-10am and 6pm to 9pm). The commercial sector itself accounts for approximately 10% of the electricity consumed in South Africa.

As a leading property developer, asset manager and property manager in Southern Africa, Old Mutual Investment Group Property Investments embarked on an ambitious project to improve the energy efficiency of the commercial buildings in their portfolio. They started by targeting those buildings that consume the most energy and which would benefit significantly from energy savings on heating, ventilation and air conditioning (HVAC) systems. The targeted buildings included two shopping centres, Cavendish Square and the Link, and three office blocks, Safmarine House, ABSA on Grove and Mutual Park.

This Demand Side Management (DSM) project had two objectives:

Firstly to reduce load by improving the energy efficiency of pumps and fans and, consequently, improve the performance of the HVAC systems.

The second objective was to shift load out of the Eskom evening peak hours (6pm – 9pm).

These objectives were achieved through the use of Energy Management Software, HVAC controls hardware and VSD (Variable Speed Drives) technology.

The application of chiller energy management software and hardware allowed the number of installed chillers in operation to be restricted, thus allowing significant energy saving since chillers are the largest consumers of energy in the HVAC system.

The installation of new switching circuits and incorporating them into various building automation systems allowed non-essential parts of the HVAC system to be switched off prior to or at 6pm achieved the load shifting objective.

This project proposed by ELSHOVE & PRYCE CC estimated an average demand reduction of 3.941 MW during Eskom's peak period (6pm – 9pm). These are significant savings for commercial buildings.

The DSM partnership programme offers financial assistance for viable energy efficiency projects designed to make businesses and buildings more electricity efficient and reduce electricity consumption. Old Mutual Investment Group Property Investments is an example of a company successfully working with DSM in order to become more energy efficient.

Energy Services Companies (ESCos) are available to investigate if similar savings opportunities exist in your business. To participate in the drive towards energy efficiency contract Eskom DSM or an ESCo directly (ESCo list available from the DSM website).

Energy efficiency is growing in importance throughout the economy as commerce and industry realise the gains to be made from using resources with care. Eskom actively promotes and supports electricity savings projects to ease pressure on the supply system in the short term and, more importantly, to help South African citizens and businesses to permanently change their electricity consumption patterns.

The surplus capacity that characterised Eskom's power system for decades has been eliminated due to growing consumer demand. The system will therefore be tight over the next five years with an increased likelihood of power interruptions. A cornerstone of Eskom's response is its Accelerated Energy Efficiency Plan, which aims to minimize supply interruptions in the short-term, while decreasing South Africans' overall electricity consumption in the medium- to long-term.

Eskom is tackling the challenge in two ways - by increasing the electricity supply, and by seeking to influence consumption patterns, particularly at peak periods. Peak periods are from 7am – 10am and 6pm –9pm.

Businesses around the nation are taking on the challenge to become more efficient – with Eskom DSM support. Visit the website for a comprehensive overview on the Eskom DSM programme at www.eskom.co.za/dsm.