Strathmore’s T3 Grid Tie Course Students Learn About The Vitals When Implementing Grid-Connected Solar PV Projects
Recently our solar students were joined by Simon Graaff the General Manager of Sustainable Power Solutions (SPS) Kenya, to learn more about the intricacies of good practice when it comes to implementing a successful grid-connected solar PV project.
Simon, who studied MScEng in Mechatronics at Stellenbosch University, started working at SPS in 2015 as a Project Engineer and has been involved in over 20 solar PV projects with the company throughout South Africa, Namibia, St. Helena Island and now Kenya. His expertise has extended to not only include pure grid-connected projects but also off-grid and hybrid projects too.
For the students, having a practical understanding (real-life project case studies) to build on their theoretical knowledge is paramount to learning, which made having Simon come to guest lecture very beneficial. During the talk Simon discussed grid-connection in the broader context, examining each step of the process which the solar students would soon find themselves performing once entering the working environment. Some of the progress steps covered during the talk included; system design, logistics, plant hire, safety, site establishment, structures, solar modules, inverters, cabling and integration, and final inspection and commissioning of the plant.
Simon highlighted that when it comes to any solar PV project the client’s energy needs are key to ensuring a successful outcome, one does not want to generate an excess of power resulting in unnecessary costs for the client. With that in mind, one of the major factors to consider during the system design is matching the client’s consumption to the simulated production of the PV plant, keeping in mind all seasonal variations of potential PV generation over the year.
Other notes to highlight during system design include the available space, conditions, access and electrical layout for the plant amongst other factors. Some designs are not your stock standard and require ingenuity to make it work effectively, especially those cases where there is not a metal concealed fixed roof in place! In the event where there isn’t enough open roof space to work off the standard 10m2 per kW, engineers and solar technicians need to get creative to find the perfect solution for those clients!
The logistics and plant hire form an integral part of the project life phase, without foresight in one’s planning, solar technicians may run into some unexpected scenarios or time delays. When working with heavy equipment such as cranes and forklifts which are used to lift the panels onto the roof, solar technicians need to adhere to the toolbox talks which ensure the project runs smoothly without any injured technicians! Some of the biggest risks when it comes to safety are falling and electrical shocks, every time technicians start on a new project a safety risk assessment is required.
For solar teams, getting to the site establishment phase is where it starts to get exciting, this is when the project becomes prepped for the rollout. Laying down the structures (often aluminum rail mount structures) is where it all begins, which is followed by applying the solar modules. There are plenty of solar modules on the market as solar PV becomes the leading renewable energy technology of the future. One key distinction to identifying an excellent module for project use is by looking at the power output rating and the technologies used, such as polycrystalline, monocrystalline or thin-film for example... bearing in mind that each technology is optimal in varying circumstances. A major point which Simon highlighted to the students was the necessity to ensure that modules are secured as soon as they are placed on the roof, too often this small error can result in major losses and risks due to the modules being blown off the roof.
The students went on to learn about DC cabling and integration thereof, where Simon highlighted that one must always ensure that the cables are not damaged by the elements and that they are properly earthed in a cable tray. As for the integration, technicians must always be well prepared and maintain communications on site as power outages will negatively impact their operations. The final stages of the project include inspection and commissioning, this involves ensuring that the solar modules are performing as expected. At this point, the solar technicians get to see that all their hard work on a project has paid off before handing it over to the client.
For the solar technicians, being on site constructing solar projects is the highlight, getting to be part of the project from inception right through to close! For students who enroll into solar technical courses, they will find themselves always working closely on the projects and may even find themselves in a Site Manager or Project Manager role in the years to come!