Rolling blackouts have swept across the country. That Eskom has slipped back into load shedding should not come as a surprise to anyone. But what should come as a shock though is the scale and magnitude of the most recent grid collapse and the worms that are now crawling out of the wood work.

The ins and outs of solar PV

While the average cost of grid electricity (residential) is now teetering at R2/kWh and facing massive annual hyper-inflationary increases, solar is dropping all the time and now comes in at around 90c/kWh. Besides the costs of grid electricity, there is load shedding which wreaks havoc with your productivity and security – at home and at work.

Solar Photovoltaic (PV) systems make use of the sun to generate electricity during daylight hours. And because solar is a technology and not a fuel, there are no ongoing costs after installation as is the case with gas for example.

Right now, solar PV delivers at least a 15% return on investment each year based on electricity savings, far outstripping any other investment vehicle where you could place your money.  Investing in solar to save on your electricity costs is a no-brainer, and the very best investment you can make right now for your business or home over the next 20-25 years. The caveat of course is that you get your system specification correct from the start, for your needs, with a renewable energy partner who will be around to provide the support and back-up for the lifetime of your system.

What is rooftop PV?

A rooftop photovoltaic (PV) system has its electricity-generating solar panels mounted on the rooftop of a building or structure. Solar panels are exposed to sunlight or solar radiation and generate electricity which is called a photovoltaic effect. This solar power flows via cable to a device called an inverter which converts the direct current (produced from the panels) to alternating current. With the inverters synchronising the solar power and the Eskom grid, that power can be fed directly into your internal electrical network and save electricity. So every KWh generated by the solar system is a kWh less required from Eskom or local municipality.

Planning for PV

Planning for a PV system will require you to analyse your electricity use, implement energy efficiency measures, study local council codes and feed-in requirements (if any), decide if you want to operate your system entirely off grid or use a hybrid or grid-connected solution, and then finally select, the technologies to help you meet your objectives. And because your system is going to be working for the next 25 years, you need to be sure about working with a supplier that has the network, financial stability, product quality and warranties in place to maximise your investment.  Reputation, credibility and the expertise of your renewable energy partner are fundamental to you realising the maximum benefit from your PV investment.

Why do I need to implement energy efficiency measures beforehand?

Implementing energy efficiency measures before you buy your PV system will reduce your electricity load and allow you to buy a smaller and less expensive system.  For example, converting geysers which are usually your biggest electricity users to solar or heat pumps, installing LED low energy lighting, using gas for cooking, putting movement and day/night sensors on office lighting and so on.  If you’re designing a new building, consider working with the architect and builder to incorporate renewable energy solutions into your design from the outset.  In fact, some measures are already legislated. SANS 10400-XA: Energy Usage in Buildings, and SANS 204: Energy Efficiency in buildings requires a focused solution for areas such as water heating, whereby 50% of all hot water in new buildings needs to be produced by methods other than electrical element heating.

Analyse your electricity usage – No shooting in the dark

Calculating your electricity needs is the first and most critical step towards getting PV ready.  A thorough examination of your electricity needs helps determine the following:

  • The size and cost of the system you will need.
  • Fluctuations in your energy usage during the day and night and over the months to manage peak demands.
  • Energy saving measures you can implement to reduce your electricity use before installing PV so that you save on the costs of a bigger system simply by being more efficient.

By conducting a load analysis, One Energy will record the wattage and average daily use of all of the electrical devices that are plugged into your central power source such as refrigerators, lights, televisions, PCs, power tools, machinery and computer equipment. Some loads, like your refrigerator or electric fencing, use electricity all the time, while others, like power tools or large format printers, use electricity intermittently, known as selectable loads.

Some providers will ask you only for an electricity bill and attempt to provide a PV solution based on this, but the approach is fundamentally flawed and inaccurate since your bill cannot reveal day and night usage, selective loads or peak demands which need to be factored into your PV solution. A thorough load analysis is a must – anyone who tells you differently simply isn’t prepared to the important groundwork you need to be sure you get the right solution. In many instances, we often unearth long-standing electrical problems and faults at client premises that need rectifying simply by doing the energy audit.

That’s why with One Energy, we’ll visit your premises, set-up loggers on your electricity distribution board for at least a week to ten days and provide you with a comprehensive view of where your electricity usage is going, and what steps we can take to help you reduce it.  We will also be able to provide a very reliable indication of what your savings will be depending on what size system and the solutions we specify for you, so there is no shooting in the dark. Ever.

What is the cost to install PV?

Many people believe renewable energy is too expensive without actually doing their homework. When we take them through the costs versus the savings and the fact that their savings can even finance their move to renewable energy, most are stunned at how absolutely affordable it is. In fact, on a monthly repayment option, in many cases the monthly finance payments are covered by what they would be paying on electricity costs anyway. Once paid off, you’ll be smiling even more!

If we look at a typical PV system, your initial capital layout would be in the beginning when you purchase the equipment and on average takes between 5-7 years to offset the costs, but then for the expected 25 years of the lifespan of your panels, you will get free electricity. In reality, even at the end of 25 years, your panels will still be 80% efficient.  The initial upfront cost is the only cost involved with solar. After that, because there are no moving parts, the maintenance on the system is very low.  Once fully paid, you have an incredible investment and asset for your property that keeps saving you thousands of Rands each year, for many years to come.

Another advantage of PV is that it is entirely scalable and can be ramped up as your requirements demand and, more importantly, your budget allows – the caveat, of course, is that you invest in the correct inverter and equipment from the outset with a professional installer who understands your long-term objectives, and factors this into your planning.  Most people will need to take a phased approach to reduce their reliance on the grid to as near as complete as possible, so mapping this process for the beginning is critical so as not to incur unnecessary costs at a later stage.