The SABC, in conjunction with Johnson Controls, has implemented a five-year energy management project that, three years into the initiative, is delivering operational savings of more than R500 000.00 a month.
The solution, which included the refurbishment of plant equipment, the modernisation of approaches to energy usage and the adaptation of control processes, has proved advantageous to the SABC on a number of fronts.
The financial model employed ensured the broadcaster was exposed to no risk and had no initial capital outlay. More importantly, however, the SABC's ability to prove sustained energy efficiency gains of 19% a month have enabled it to enter into a highly beneficial agreement with City Power in terms of guaranteed up-time – a mission critical requirement for the broadcaster.
Bruce Phipson, building technology manager at SABC, explains: "In 2005, the SABC took a strategic decision to reduce its energy consumption. At the time, our electricity usage accounted for 25% of our operational costs. We considered a number of alternatives but selected Johnson Controls proposal for its depth and breadth of insight into our operations, their familiarity with our systems and challenges, and the financial model they proposed."
The SABC's premises in Auckland Park comprise eight buildings covering 174 000 square metres. They include radio and TV studios that accommodate about 6 000 permanent and contracting staff. Plant equipment includes nine chillers and 128 minor air conditioning units while the lighting system includes 88 000 fluorescent tubes.
Neil Cameron of Johnson Controls comments: "Internationally, Johnson Controls has had considerable success with its zero-risk model. Essentially, we assess the company's existing systems, do any necessary refurbishment of equipment and processes and then recoup our investment over time from an agreed percentage of the savings realised. SABC's adoption of this model and its subsequent achievement of forecast savings proves the benefits of this model."
Johnson Control did a thorough audit of the SABC's existing equipment, processes and requirements. This included using sophisticated software that used measurements and engineering analysis to create an optimal energy/thermal balance model for the broadcaster's facilities.
"We identified possible savings and did a project analysis to prioritise the solutions that would deliver the required return on investment," says Cameron.
A key advantage for Johnson Controls was the fact that the SABC was already making use of its Metasys Building Management System. "This solution is a primary driver of energy savings, enabling the integration and synchronised management of diverse systems, such as air conditioning and lighting, and even security. However, a R1,7-million refurbishment of plant and other equipment was first needed to enable better control and introduce energy efficiencies into the operation of equipment."
This included replacement of equipment controls to introduce new, more modern approaches and standards for chiller operation.
Explains Cameron: "Of the total energy consumption of a large commercial office, 45% is typically consumed by the air conditioning system. Of this total energy consumption, 25% is related to operation of the chillers. This can be managed down with the introduction of new technology.
"In general, this plant equipment is set to run at full load, which is in reality only required about 3% of the time during the hottest months of the year. The introduction of user-friendly technologies such as Variable Speed Drives (VSDs) and capacity control solutions that enhance control mean motor speeds can be continuously and precisely matched to demands on a motor. This enables building owners to reduce chiller energy costs as much as 30% compared to constant-speed operation."
Other enhancements included pre-cooling of air taken in through air handling units and the reconditioning and reuse of returned air, which is often cooler than air taken directly from outside. Air handling units collect and mix outdoor air with that returning from the building space. The air mixture is then cooled, after which it is discharged into the building space through a ducted system.
Phipson adds: "Johnson Controls also introduced other innovations. Staff can, for instance, turn on the lights in the facilities in which they are working by dialing a code on their telephones."
A five-year agreement was struck between SABC and Johnson Controls in November 2005. The solution was fully implemented within 12 months. Johnson Controls recouped its initial investment from energy savings within three years. For the balance of the contract, which runs until 2010, Johnson Controls will receive a portion of the energy savings it achieves at the SABC.