TW Profile Services has been in operation since 1994 and has successfully grown into one of the largest service centres in the laser cutting and profile cutting industry in South Africa, specialising in plasma cutting, guillotine cutting, rolling and bending.
“Due to our high electrical consumption, we needed to look at possible solutions and selected PV as the most viable. We anticipate about a 25% saving in our monthly electricity bill,” said Joost Smuts, MD of TW Profile Services.
The panels are installed in four arrays giving an output of 55KW each. This feeds into two 100KW inverters in parallel, tied to the grid. The pay-back period is estimated at five to six years. The total voltage is 750v DC which is converted into 3-phase AC.
Passat Energy has partnered with 3M for advice on attaching the solar installation to existing roof structures, minimising roof penetrations.
“3M has assisted with the installation of the solar panels by providing a unique solution for attaching the solar panels to the roof of the factory,” said Pierre Lombard, a director of Passat Energy.
“The panels are not secured using the traditional method of mechanical fasteners where holes are drilled in the roof to secure the panels. Mechanical fasteners tend to rust after a few years and the process is time-consuming and labour intensive. Mechanical fasteners are also prone to creating water leaks,” he said.
The solution provided by 3M consists of a VHB (Very High Bonding) double-sided, adhesive-rolled acrylic tape, initially used for high-speed trains in Japan.
“The adhesive is stronger than a mechanical fastener, will last longer – up to 15 years, and bonds immediately,” said Lombard.
“The adhesive is also visco elastic, meaning it has no thermal expansion caused by changes in temperature and therefore creates zero fatigue on the roof or panel.”
“The installation took four weeks, whereas using mechanical fasteners would have taken six to eight weeks. Recent hail and high winds had no effect on the panels and they remained secure,” he said.