PPE HQ In-house 50kW Solar Photovoltaic Solar Project
PPE Technologies recently took to designing and installing a rooftop, on-grid, 50kWac solar array at our head office in Nelspruit. Not only is it a statement about our concerns for the environment and promotion of renewable, eco-friendly energy sources, it is also a smart investment. Based on a typical 25 year lifespan of a solar array and including annual de-rating of solar module efficiencies, the company stands to make a conservative estimated saving of 65% on electricity bills.
The nature of solar modules dictates that they progressively de-rate and a 25 year lifespan is typically attributed to them; after which the progressive efficiency de-rating results in the array no longer being a viable investment and the system is decommissioned. The solar array was mounted on a pre-existing helipad which had fairly extensive rust damage. Based on the 25 year life-span, the roof was completely restored by sand blasting and an anti-rust coating layered on. With this restoration work, we can be confident that the roof and structures will be in good condition by the time the array is to be decommissioned.
The company carried out an extensive cost model in order to validate the fairly high initial cost of a solar project against the cost savings in the solar array’s life span. The pay-back period for the initial investment is estimated to be around the 8year mark. The wide-spread concern of the initial cost of a solar array is being debunked as the long term investment benefits far outweigh initial expenses. Moreover, the cost of equipment is decreasing as demand for solar arrays is ever increasing, making it an ideal time to invest in solar power.
The company made use of 168 Jinko Solar modules split into 12 strings of 14 modules. These were tied into 2 ABB TRIO 27kW inverters operating in parallel which supplies 400VAC 3 phase supply to our existing main distribution board. These intelligent inverters automatically synchronize to the source available whether it is municipal or generator supplied power. All powder-coated mounting structures were manufactured in-house; a comprehensive lightning risk assessment and lightning protection design was carried out in-house with design approval conducted by our channel partners, DEHN Africa. Additionally the complete design and installation was carried out in-house with input from both ABB and DEHN in reference to their specialized equipment.
All monitoring and safety precautions have been incorporated into our “smart building” automation system. This system constantly monitors and logs the kWh supplied by the solar array, all information from the solar inverter from dc power, efficiency, fuse blow statuses and more. The system also prevents back-feeding of any kind into the grid and can automatically isolate the solar system in the event of an emergency such as a fire. Automating a safety system such as this was also carried out in-house and is far more reliable than relying on a human operator.
PPE Technologies has a complete solar solution for any industrial sized installation desired and phase 2 of our solar project will commence in October where our attention will shift to our Pretoria offices for a 10kWac solution.