Frequently Asked Questions

Suis is a sustainable energy consulting firm based in Durban, South Africa. We help residential, commercial, and industrial clients transition to clean energy through tailored solar installations, battery storage solutions, energy audits, and carbon strategy consulting. Our team of certified engineers and consultants guides you from feasibility assessment through to completed installation and ongoing support.

While our head office is in Umhlanga, Durban, we serve clients across KwaZulu-Natal, Gauteng, the Western Cape, and the Eastern Cape. For large-scale commercial and industrial projects, we operate nationwide across all nine provinces of South Africa. We also provide remote consulting and energy audit services for clients in neighbouring SADC countries.

Getting started is simple -- contact us via our website form, email, or phone to book a free initial consultation. During this session, we assess your energy needs, review your current consumption data, and discuss your goals. From there, we provide a detailed proposal with system recommendations, projected savings, and a clear project timeline.

The number of panels depends on your electricity usage, roof space, and energy goals. A typical South African household consuming 800-1,200 kWh per month generally needs between 12 and 20 panels (each rated around 450-550W). Our consultants perform a detailed site assessment and consumption analysis to recommend the optimal system size for your specific situation.

Modern solar panels are built to last 25-30 years with minimal degradation, typically losing only 0.3-0.5% efficiency per year. Most manufacturers offer 25-year performance warranties guaranteeing at least 80% output. We source only Tier 1 panels from reputable manufacturers, ensuring long-term reliability in South Africa's climate conditions, including high UV exposure and coastal humidity in KZN.

Solar panels still produce electricity on cloudy days, though at reduced capacity -- typically 10-30% of their rated output depending on cloud cover. South Africa enjoys some of the highest solar irradiance in the world, averaging 4.5 to 6.5 kWh/m2 per day, which makes solar highly viable even accounting for overcast periods. Pairing your system with battery storage ensures consistent power availability regardless of weather.

Battery size depends on what you want to power and for how long during an outage. For a typical South African home looking to cover essential loads (lights, fridge, Wi-Fi, security) during load shedding, a 5-10 kWh battery is usually sufficient. If you want to run higher-draw appliances like stoves, geysers, or pool pumps, you will need a larger system in the 10-20 kWh range.

Lithium-ion batteries (the most common choice in South Africa) typically last 10-15 years or 4,000-6,000 charge cycles, whichever comes first. Most leading brands like BYD, Pylontech, and Freedom Won offer 10-year warranties. With proper installation and our monitoring systems, many batteries exceed their warranted lifespan, making them a solid long-term investment.

Absolutely. Battery storage is one of the most popular solutions for load shedding in South Africa. A properly sized system can automatically switch to battery power within milliseconds of a grid failure, keeping your essential circuits running throughout the entire outage. We design systems specifically to handle the typical 2-4 hour load shedding stages, and even extended Stage 6 scenarios.

Costs vary based on system size, equipment selected, and installation complexity. As a guide, a residential 5 kW solar system in South Africa typically costs between R80,000 and R120,000, while a 10 kW system with battery storage ranges from R180,000 to R300,000. Commercial and industrial systems are quoted on a per-project basis. We provide detailed, transparent quotes with no hidden costs after our site assessment.

We partner with several financing providers to make solar accessible. Options include rent-to-own agreements, power purchase agreements (PPAs) for commercial clients, and instalment plans with terms ranging from 12 to 72 months. Some South African banks also offer green home loans and dedicated solar financing products at competitive rates. We help you navigate the best option for your budget.

South Africa offers significant tax incentives for solar investment. Businesses can claim a 125% tax deduction on qualifying renewable energy assets under Section 12BA of the Income Tax Act. Individual homeowners can claim a 25% tax rebate (up to R15,000) on solar panel costs under Section 6C. These incentives substantially reduce the effective cost and accelerate your return on investment.

Most residential solar systems in South Africa pay for themselves within 4-6 years through electricity savings, and even faster with the available tax incentives. Commercial systems often see payback in 3-5 years due to higher daytime consumption. After the payback period, you effectively generate free electricity for the remaining 20+ years of the system's lifespan, with cumulative savings often exceeding R500,000.

A typical residential installation takes 1-3 days of on-site work once all equipment has arrived and permits are in place. The full process from initial consultation to commissioning usually takes 4-8 weeks, which includes site assessment, system design, municipal approvals, and equipment procurement. Larger commercial projects can take 2-6 months depending on complexity and scale.

Yes, most South African municipalities require an electrical Certificate of Compliance (CoC) and notification or registration of your solar installation with your local municipality, especially if you plan to feed excess power back into the grid. The eThekwini Municipality in Durban has a specific Small-Scale Embedded Generation (SSEG) application process. Suis handles all the paperwork and approvals on your behalf as part of our service.

Solar systems require very little maintenance. We recommend cleaning the panels 2-4 times per year to remove dust and debris, and an annual professional inspection to check all connections, inverter performance, and battery health. Our monitoring platform tracks your system's performance 24/7 and alerts us to any issues automatically, so we can address problems proactively before they impact your energy production.