Car manufacturer BMW South Africa has reduced electricity and gas consumption since 2006 by 30% and 36,5% respectively.

At the same time, maximum electricity demand – which is the company’s peak electricity use – is down by 7,3%.

Electricity consumption during nonproduction time or idle time has been reduced by 40%.

The net result is an energy overhead saving of around R18-million a year, and a total saving of R29,3-million since the project began in 2006.

The project was implemented to maximise production efficiency at the company’s Rosslyn manufacturing plant, and at the Midrand head office, while reducing energy consumption.

“We realised some time ago that BMW needs to keep a firm hand on its consumption of energy, as well as the impact that consumption has on the environment, specifically in light of the company’s strategic objective to be the most sustainable vehicle manufacturer in the world,” explains BMW South Africa technical and logistics director Knudt Flor.

The vast majority of electricity consumption at the vehicle manufacturer can be attributed to the production of 3-series vehicles for the local and export markets.

The production process is particularly energy intensive with regard to the conveyance of the cars from one area of the production line to another.

Heating, ventilation, cooling and lighting of production areas within the plant are   also major energy consumers.

“We had to come up with clever solutions to reduce lighting capacity, as an example, without negating the importance of health and safety issues,” explains Flor.

To this end, lighting in production areas has been linked directly to the production schedule, for example.

In other words, lights remain off on non-production days. The same applies outside of office hours at the company’s Midrand head office.

In addition, solar water heaters were fitted to the boilers in the paint-shop.

These heaters are also used to heat ablution water for the 400 employees working in this area of the plant.

Meanwhile, unused areas of the plant have been mothballed, instead of standing empty with the lights on.

Gas is also quite critical in a vehicle production environment, as it is used to fire ovens in the paint process. Here too dramatic changes were made.

Thanks to advancements in technology, a new type of body sealant that does not require oven curing was introduced.

This means that the particular oven used for this process was mothballed, saving a large amount of gas every day.

Previously, each car was cured for between 35 and 45 minutes in this oven alone.

“Our facilities and energy department sends a fortnightly report to all plant employees on BMW’s expected power usage for the next 14 days,” notes Flor.

“At the same time, the report gives feedback with regard to where the greatest energy losses are, and offers recommendations on the actions required to meet the monthly targets.”

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