How to

The first thing we need to get out of the way is that this article is aimed more at the domestic user rather than the business user. Though there are overlaps, obviously, each will be very likely to have very different requirements in terms of what needs to be operated and when, and therefore system capacity, peak usage times and so on.

Another point to bear in mind is that as comprehensive as this article aims to be, it is unlikely to be definitive; technology is advancing all the time, bylaws and what-have-you change, and other factors conspire to ensure that the situation is in a constant state of flux. Costs of some items rise, other decline… Hence…

Disclaimer
While every effort has been made to ensure the details and information contained in this article are correct and applicable at the time of writing, it is the homeowner’s or business owner’s sole responsibility to ensure to their own complete satisfaction that they have carried out all the required due diligence measures to ensure that the system they select is installed by a competent and properly accredited contractor or contractors and that all relevant and applicable municipal or other statutory regulations are adhered to.

Bottom line… depending on the size of the system you have installed, your solar system could be one of your biggest purchases after your home and your vehicle, so you MUST ensure to your own complete satisfaction that you have covered all the bases.

Sort out your current system
First of all, if you have experienced any problems with it, such as the lights or circuits tripping every so often, it is a good idea to have a qualified and registered electrical contractor check your system as it is right now… that all circuit breakers, plugs, wiring and perhaps including your home’s earth rod etc are up to standard. The latter, for instance, might over time become corroded and could need to be replaced.

This means you will incur some expense upfront, but it also means that once your solar system is installed if there are any issues – tripping, for example – at least you can be pretty sure that it is not your home’s current/original system, that is at fault.

Secondly, either while your current system – pardon the pun – is being checked and any faults made good, it is as well to draw up the most comprehensive ‘wish list’ that you can of things you want to be able to work off the solar system, so that you can supply this information to the three contractors or more you have selected for quotes. This will give them as much information as possible on your current usage and your home details, as roof material, slope, direction relative to North, and other factors such as roof area available for panels.

To stress… the following is very much a wish list and when it comes to the size and capacity of the system you end up with, there will very likely be some give and take, and timing of various services to make best use of your solar and battery power and as little use as possible of power off the grid.

Wisdom seems to suggest that as erratic as the grid is, it is a good idea to stay connected to it – even if not using it – just in case you encounter a problem with your system at some stage down the line. At least you then can have a backup, even if it is erratic, while your solar system is sorted out. once your system is installed you might also find on days with passing clouds that every so often you will draw 20W or so off the grid. This is because as a cloud passes between your panels and the Sun, panel output can drop even for a minute or so. The system picks this up and makes up the shortfall from the grid.

So, first… your wish list and home details…

ELECTRICAL APPLIANCE/NEEDS – JOE BLOGGS – 195 SANITARY LANE, OLD TOWN,

List of appliances/electrically-powered installations

Air conditioner system/s

Chest freezer

Cordless tool chargers – 8

Dishwasher

Electric gate & garage doors

Fan/s

Fax machine (yes… some people do still ‘ave ‘em)

Food mixer

Fridges – 2

Hair dryer

Heater – element

Heater – fan

Heater – oil

Heater – space

Hot-water geyser

Irrigation pumps – 2

Kettle

Laptops – 2

Lights – back-up – 4

Lights – main

Lights – security – 5 – 5-7W low energy

Oven – air fryer

Oven – main

Oven – main – top hotplates

Oven – microwave

Oven – small tabletop

Phone rechargers – 2

Pool pump

Power tools – saw, drill, router

Printer

Rechargers – 2 – cordless tools

Security system

Toaster

Tumble dryer

TVs – 2

Washing machine

Distances from panels and inverter/batteries to main DB

Approximately 5m.

This is an approximation only as the contractor might well decide that the position you have chosen for the inverter and batteries etc, is unsuitable, so they could be closer or further from the panels and main distribution board (DB). This will affect the amount of cabling, for instance, that is required.

Roof particulars

  • Roof is due-North-facing
  • 20° slope (bear in mind that the steeper the slope, the greater the roof area for the horizontal area it covers when viewed from directly above – the illustration below demonstrates this clearly. All three roofs have exactly the same ground area, but the steeper the slope, the greater the slope area, and hence more space for panels… just the same as with roof tiles… the greater the slope, the more you need for the same length of roof of a lesser slope. Geddit?
  • Roof is tiled
  • Approx half of main roof covered by pool heater panel (water heating, no electricity usage)
  • Remaining space on main roof section available for PV panels has been measured at 5.5m wide x 4.35m from peak to just short of the lower edge. (The amount of space – on the slope – will determine what size and how many panels can be fitted.
  • Two smaller sections of roof (same slope of 20°) are approx 3.3m x 2.5m (East side [w x h]) & 3.5m x 3m (West side [w x h])

Home particulars

Four bed-rooms, sitting-room, dining-room, two bathrooms, kitchen, laundry, double garage.

Factors to bear in mind (not necessarily in order of importance)
Some of the following may apply in your case, some might not and there could be other factors to be borne in mind in certain instances – such as the crucial need reliable power 24/7 for medical equipment, for instance)

  1. The ideal is to use the Sun as much as possible, then the batteries, and finally – as a last resort – the grid to power your home – the latter as little as possible.
  2. Bear in mind the above list of what you have in the house is very much a wish list. Unless you select a system large enough to handle, essentially, everything on the list simultaneously, you will need to do some trade-offs in terms of what is used and when, so that usage is staggered.
  3. For instance main usages might be (and these are only suggestions to show what I am getting at)…
    Fridge and freezer on intermittently 24 hours, so no control by you
    Hot-water geyser on 0600-0730
    Pool pump 0730-1030
    Washing machine 1030-1130
    Stove/oven 1130-1300
    Pool pump 1300-1500
    Dishwasher 1500-1600
    Hot-water geyser 1600-1700
    Stove/oven 1700-1900
    A schedule along these lines, and subject to advice by your contractor, would mean that on a sunny day and particularly in summer, your panels would be providing most if not all of your power and charging your batteries at the same time, with little or no grid power being drawn as a last resort. Then your batteries, now charged to 100% of capacity, tide you over during the night for your TV, lights, intermittent fridge use, and electric heater in winter and so on.
  4. Bear in mind that in all likelihood, your electricity usage now and from when load-shedding began has been skewed by the repeated and frequent blackouts, which has reduced your overall usage to some degree. Thus your figures for your usage will be lower than what it would be in normal circumstances.
  5. Hence, once you have your solar power installed, and depending on its capacity, you could end up using more electricity, thanks to your solar system providing a more consistent supply even while all about you is in darkness.
  6. So factor this in by discussing it with each contractor from whom you are getting a quote and then try to estimate as accurately as possible what your normal usage would be (and what usage you would like to enjoy once your solar system is up and running) and then plan accordingly. It is as well to mention here that each potential contract must get exactly the same information, otherwise could end up comparing apples with pears.
  7. The aim is to get as close to normality as you can without breaking the bank.
  8. Check your neighbours and ask those who have systems installed who they used, their satisfaction with the system and the after-sales assistance provided, and any other points they might feel are relevant. Do not underestimate the value of a good after-sales service record.
  9. Insist on using accredited, qualified contractors – and insist on checking their accreditation documents, but please bear in mind that according to what I have found out, local authorities do not “accredit” or “approve” contractors.
  10. The ideal is to use established companies with a successful history. That can be your first option, but bear in mind that even the world’s largest companies at one time were new on the block and just starting out. So NEW does not necessarily mean NO! But insist on checking their accreditation documents.
  11. Check that all the contractors from whom you get quotes are paid-up and current members of the relevant association/s such as the South African Photovoltaic Industry Association (SAPVIA), Africa Solar Industry Association (AFSIA), Southern African Alternative Energy Association (SAAEA), Sustainable Energy Society of Southern Africa (SESSA), Association for Renewable Energy Practitioners (AREP), African Sustainable Energy Association. But bear in mind that most likely in all most cases, these organisations while insisting their members meet particular standards etc, they are not policing agencies. If you have a beef with your contractor, that is who you argue with – not the umbrella association.
  12. When considering which contractor to go with insist right at the beginning, when you pay over your deposit, that they begin the City or local authority approval and registration process immediately and insist that the company provides you with the necessary proof thereof – a registration number and/or forwarded copy of the registration application. And prior to the actual installation, proof of the City’s/local authority’s approval for it… just to avoid any nasty letters from either one of them.
  13. You will also possibly need to replace your existing meter with the new-technology split-prepayment meter. This installation, depending on what arrangement the City/local authority has set up, may be free if you will have or have solar installed. In the case of the City of Cape Town, for example, it appointed a contractor to carry out the work on its behalf. In this particular case, one contacts the specified contractor to set up an appointment day to do the work and this is followed by a message a couple of days prior to the day to confirm that actual time – so make sure you are home.
  14. Without breaking your bank, beware that going cheap risks going twice. Find out as much as you can about the reputations for the various components; something that costs a bit more can be a far better use of your cash than a cheaper version that doesn’t measure up in terms of quality, durability or efficacy. Bear in mind that during winter the shortest days/longest nights are around June-July. (During the June solstice [marked between June 20 and June 22], solar declination is about 23.5°N [the Tropic of Cancer]. During the December solstice [marked between December 20 and December 23], solar declination is about 23.5°S [the Tropic of Capricorn]. So in June/July there is less energy available from the Sun, so this will affect how charged up your batteries can be, and also longer nights mean more power drawn from them – particularly if you use any heater – space, fan, oil or element – to keep warm.
  15. Also bear in mind that cloudy/overcast weather will reduce the Sun’s energy.
  16. There is a great deal of dust, pollen and other matter in the air so make a habit of every so often… once a week or so, in either the early morning (before the panels have heated up) or in the early evening (when they have had time to cool) give them a spray with your garden hose. There’s no need to go up a ladder. Just do it from the safety of terra firma, and give the panels a bit of a rinse-off.
  17. In summer, you might have a fan going, or you might also/alternately have air-conditioning. However, as per Point 14, long days with the Sun far closer to overhead, your panels will be generating their maximum power for far longer.
  18. Select a space in your home or garage in which to install the solar system hardware – inverter, batteries, etc – which is as cool as possible, ventilated, and secure – and which allows for expansion to the system… such as extra batteries.
  19. Depending on the type, manufacturer etc, the equipment may be totally silent, very quiet, hum away a bit, or hum away a lot, so if putting the setup into a room in a the home, bear the noise factor in mind. Be guided by your contractor.
  20. Ensure that wherever you have the equipment installed is secure, protected by sensors which are linked to your main security system.
  21. Insure the whole setup via your homeowner’s insurance policy (see more detail below).
  22. At the time of writing, stealing solar panels was the new ‘in’ thing. Discuss with your security provider and/or the contractor as to what protection devices might be possible – pressure sensors, PIR sensors covering the panel and so on. Intruder alarms work by detecting when someone has broken into the protected area. The sensors of an intruder alarm are usually motion detectors, but they can also be pressure pads or infrared beams. Ones you might consider – either as single types or in concert with other detectors are: PIR (passive infrared motion detectors), dual technology motion detectors, acoustic glass break detectors, electric fences, vibration/shock detectors, magnetic contact detectors, boundary beams, pressure sensors. Consider video surveillance so you can see what is happening before you take action, and with remote monitoring so you can keep an eye on your property from anywhere – even in another country.
  23. Don’t be a shady character… Yes, you love that tree little Johnny loves climbing and which gives you so much shade, but if it also shades your roof panels, even a little, your system will not be as efficient as it could be. So cut it back – or down – so that your solar panels get every proton of light that they can from the Sun.
  24. Bear in mind that if you live in a housing complex or flat, your body corporate/landlord might well have particular requirements that have to be met. Body corporate are managed in terms of the Sectional Title Schemes Management Act and installations such as solar power panels etc will be subject to various approvals, rules and so on.
  25. Consider making your solar system an income generator… as time passes more cities and local authorities will very likely establish schemes to allow domestic solar users to sell excess power back to the grid. Nice idea, great idea… but ensure you are fully aware of ALL of the costs involved. My suggestion is use your solar system for a few months and monitor your usage on a daily/weekly and monthly basis, so that you can get used to it and also establish very accurately how much power you need and when and what excess you might have. Then consider the following:
    • The cost, including installation of the bi-directional meter that will be required, plus any additional wiring. The cost is coming down, but even at the time of writing, the cost in Cape Town was around R11000-R12000 installed. There are moves to make it more economical, but let’s wait and see.
    • What service/admin fee you might have to pay.
    • What bright, high-voltage idea might Eskom dream up to charge you for NOT using their electricity?
    • What the city/local authority will pay you per unit for the power you provide.
      Any other costs, such as additional insurance to cover the meter.
    • Now… how much excess energy will you be able to supply? Using your figures, you can…
    • Work out how much can you REASONABLY (always veer towards a lower, conservative figure, not the one you hope for… unrealistic expectations lead to great [and possibly very expensive] disappointment) expect to get in your account every month or see as a reduction in your monthly rates/utility bill?
    • Given the costs involved, and the conservative supply figures you have worked out, how long will it take to amortise your costs?
    • OK… so now is it still worth it?
  1. The closer your longest roof is to True North the better. Note, True North, not Magnetic North, which is at the moment in Northern Canada at 81°18′N 110°48′W. (for instance, Cape Town’s magnetic declination is -25.36° – or 25.35° West, so when you use a compass to check, due North is 25.36° (just make it 25° West. Magnetic declination in Johannesburg is -18.97° (make it 19°) Magnetic declination in Durban is -25.78° (make it 26°). If you live in any other area of South Africa, refer to www.magnetic-declination.com to check your declination. Or if you want to do it the lazy way, go to your house on Google Earth (surely you are on the internet?) and check its orientation there. Naturally, your solar panels will be fixed to your Northern roof.
  2. If your home is more East-West, then you could – I stress ‘could’ find that your panels could be fixed to both sides of the roof, the West side getting the early morning Sun (the East side less so), both getting the midday Sun, and the East side getting the afternoon Sun (the West side less so). As always, however, be advised by your contractor as to the best options available to you.
  3. Consider having a geyser timer/controller installed (at the time of writing at a cost of about R950 installed) so that you can set the On/Off times, and also the thermostat temperature. So what should the geyser thermostat temperature be set at? Some sources suggest the industry standard temperature in SA is 50-55°C in summer and 60-65°C in winter. The setting should never be lower than 50 degrees as this will promote bacterial growth in the water. However, I would be wary of setting the temperature to the maximum of 70°C if there are young children in the house, or visiting… water at that temperature could be extremely painful if not downright dangerous, so a lower setting is safer. The other issue to consider is that we usually require hot water in the morning, for our morning shower, and again in the evening for the evening soak or shower. During the day while we are at work the geyser is switching on and off – when we do not actually need it. So setting a timer to heat water from, say 0500-0600 (geysers usually take about an hour to heat up from cold) and in the evening from, say, 1700-1800, could be considered. Of course, in winter the above times are when it is pretty dark, so the power for your geyser will come from your inverter and batteries, with top-up from the grid if available. However, also bear in mind that the insulation on modern geysers nowadays is so good that with no use during the day (hence, no ingress of cold water to top it up), at neither time will the geyser be heating up from a cold start. Again, chat to your contractor and other experts to decide on the best regimen for your needs. Research from Stellenbosch University’s Water Institute found a connection between geysers and the increase of Legionella, a bacteria that causes severe pneumonia and can become a major health issue in your hot water geyser if the thermostat is not set high enough to prevent the bacteria – which research has found cannot survive in water hotter than 50°C.

Costs and other financial factors

Aah… the vital question – what will a system cost? And the simple answer is: How long is a piece of string?

From the very basic candle to paraffin lamp to back-up lights to inverter to generator to solar panels and batteries etc each carry a cost. However…

I think the key is not to look at costs strictly in a cost/time to effectively amortise those in a costs sort of way, but rather – while taking them into account, obviously – also look at the freedom from blackouts you can enjoy, the freedom to watch your favourite TV shows even when all the homes around you are dark, the freedom to have a cup of coffee whenever the fancy takes you… and the very, very important freedom to know that your home security system is always up and running. In my case, a big plus is being able to run my mains power tools whenever I need to – without having to dodge blackouts.

So now to the nitty-gritty: the costs of the various components for a solar system… so, at the time of writing…

Panels:
As per usual, the more powerful/larger the panel, the higher the cost, so 345W monocrystalline solar panels cost about R2500 and 550W monocrystalline solar panels cost about R4500. Prices naturally vary from brand to brand, power to power, and supplier to supplier. One quote for panels I requested came to ten 425W with a unit cost of R2762.30 – for a total cost then of R27623.

And of course the other factor is that as technology advances, so the panels are becoming more efficient and with luck, their unit cost will also tend to decrease at least a little. Well we can hope!

Depending on the capacity of the system you intend having installed, you could require anything from 6 to 10 panels (or on either side of this range). Your proposed installer will advise you, but among the factors to consider are primarily your requirements subject to day length and of course, cloud cover. The panel installation shown in this feature comprises 10 550W panels. And even on an overcast day, they are able to fully charge the 10kWh battery storage installation by about 1100, and in doing so, simultaneously also power various appliances and operations in the home, which means no power is being drawn from the grid.

As to day length, our fewest hours of sunlight are in June/July, and the Sun is closer to being over the Tropic of Cancer, so that will also affect output.

The above example of solar generation was taken in early May, so we were not experiencing the fewest hours of sunlight yet, but getting there.

Of course, as we then head towards spring and summer, hours of sunlight are much longer, the Sun is closer to directly overhead, and we can expect the panels to be producing a great deal more than in winter.

Batteries:
Two 5.5kWh lithium batteries at a cost of R24000 each. It is as well to ensure that when discussing your electricity needs with your contractor that you confirm that if necessary, or if desired at any time in the future, you can expend the system by adding an extra battery or two, for instance. (Who knows… you might win the Lotto!)

Inverter:
One 8kVA unit at a cost of around R48000.

Additional costs:
In addition to the above you will also need to add the various other components such as lightning protectors, cabling, mounting brackets, labour, local authority registration costs, travel, and VAT. (These should all be listed in the quotes from the contractors so you know exactly what is being paid and for what.)

Warranties:
Warranties vary according to the component and what is provided by the manufacturer, so for example:

  • Inverter – 5-year manufacturer warranty
  • Batteries – 10-year warranty
  • Tier 1 panels – 25-year warranty
  • Mounting – 10-year warranty
  • Total cost therefore for two batteries, inverter, ten 550W panels, plus various lighting protectors, mounting brackets, cabling, various other components, labour etc can cost in the region of R190000, to which you need to add VAT. Naturally, as always, costs can and will differ according to the size of the system brands of components used, number of panels etc.

Insurance:
Whatever the size of the solar system you decide upon, it is of course important that you have it ensured as part of your householder insurance.

You can usually do this only one the system has been checked and certified by your city/local authority. This will increase your premiums, but the alternative of having to replace parts of your system if they are not covered but are stolen, is far worse. Naturally, your system warranties cover only normal wear-and-tear, and other factors that can affect their functioning, but warranties do not cover theft – just as insurance does not cover normal wear-and-tear.

As just mentioned, you very likely find, however, that your insurer will not add the system to your policy until such time as it has been certified, and that could take a few days, weeks or even a bit longer – like months – depending on how many systems the certification engineer has to certify and how long it takes the relevant city department to process everything.

Hence, you will require a Certificate of Compliance (CoC) and your SSEG registration with your local authority. SSEG is the acronym for Small Scale Embedded Generator and refers to electrical generators (smaller than 1MVA [1000kVA]) that can be connected to and be synchronised with the grid to operate in parallel with it. Such systems are termed embedded generators.

In the meantime therefore, ensure that the space in which your system is installed is equipped with the necessary security devices such as PIR (passive infrared) sensors and magnetic alarm.

Selling back to the grid:
I did cover this above, but mention it here again as it is also relevant here… at the time of writing, cities such as Cape Town are in the process of setting up systems to enable consumers with solar power to sell their excess production back to the local provider, be it city, municipality or Eskom and be credited.

This requires a bi-directional meter, which allows excess electrical current to feed back into the grid and for which the supplier – now the business or domestic user can be paid, depending on the arrangement set up the local authority, as a direct payment into the user’s account, or possibly a credit off the rates bill at the end of the month.

However, according to Solar-Panel.co.za (https://www.solar-panel.co.za/), at the time of writing “the biggest set-back to the bi-directional meter is that the user is charged a fixed rate for installation and this amount is currently in the region of R12.36 per day. An additional downside is that the buyback amount for the excess electricity is 72c per unit compared to the R2.30 charged by the power utility per unit to supply. So in order to cover the costs of the installation you need to produce at least 17.2 excess units per day, just to break even on the installation costs before you can start to see ‘earnings’ from the excess electricity you may have produced”.

Cape Town City is apparently looking at ways to bring down the cost of installation (at the time of writing about R11000 to install the meter) and plans to have a scheme set up by the end of 2023 to allow domestic users to sell back to the city, but still, at the time of writing, is being remarkably coy about what domestic users will have to pay in terms of any monthly administration levy or daily rate for the pleasure of feeding their excess power back into the grid.

So at the very minimum, you need to be fully aware of these facts:

  • Costs of installation
  • Monthly levy/daily rate you will have to pay for the pleasure of putting your power back into the grid
  • Amount of excess electricity you are producing every day – on average over a 12-month period
  • Amount paid to you for the electricity you supply to the grid

It is therefore probably best to keep abreast of developments in the above, and also keep a very accurate record of your usage over quite some time – I would suggest around a year – and I mean a year!

This will enable you to judge quite accurately what your usage is during the various seasons, and from there, decide whether taking this route is worthwhile.

The other possible factor is SARS and tax:

There is an old joke about a notice stuck up in every tax office to the effect “If We Can Bring A Smile To A Taxpayer’s Face Today, Someone Here Has Screwed Up”…

So if you are deriving a benefit from your solar installation, apart from the sheer pleasure of watching your favourite show while all around you is dark, the taxman may well decide that you are earning an income/benefit and tax you accordingly. And if this pushes you into the next tax bracket, you will be hit with a double whammy.

So, therefore, if on looking at your generation and usage figures you find that at whatever costs and rates/levies/possible taxes etc are at play at the end of the 12-month period, you are either never going to pay off your bi-directional meter within a reasonable time period of, say a couple of years, or it will actually cost you extra, then it is very likely best to do no more than sit back and enjoy your favourite show.

Eskom levy?
It is not impossible that Eskom in its wisdom might impose on businesses and domestic residences with solar power, a levy for NOT using Eskom power – rather like the SABC charging you a TV licence even if you have not watched anything on their channels for decades.

Home resale value
Why did you buy your home? The simple and in the vast majority of cases the correct answer is to live it in and raise a family in it.

But times change… we move to a different job and want to live closer to our workplace, or we have raised our family and they have moved out – at last! And now we want to downsize. Or our bond repayments have become too large for comfort… or we are going into a new relationship or ending the current one. Or we are old coffin-dodgers and want to move into a retirement home, or we are emigrating… there are myriad reasons for people wishing to sell their homes.

And that is where having solar already installed can be a selling point.

Certainly right now, all things being equal, it is a big plus. But as times move on and more people have solar installed, so it might well become a real negative if you want to sell and you do not have solar installed.

All of that means that when it comes to selling, you likely recoup your entire solar installation outlay and then some, or at least achieve a better selling price for your home.

Is that a leak I see?
An unfortunate fact of life is that as your panel will very likely be mounted on your roof, the attachment brackets will need to be attached to your roof trusses and/or battens so that the panels are very securely fixed in position. That means there is a possibility that you could find a leak or two following installation and when you get your first bout of rain.

Ensure that this is factored into your contract with the solar installer. If you have the system installed in rainy season in your region, you are likely to soon discover if there are any leaks. If, however, it is installed during your region’s dry season, it could take weeks or even months to discover your roof is leaking.

Ensure you and the installer are very clear on this; reputable installers are almost certain to include leak repairs in their quote so there is no extra cost to your account… leak repairs are factored in from the very beginning.

So, after your first rains, check ceiling and walls for any damp. You can also stand in a room, turn off TVs etc and tell the family to keep quiet, close your eyes and listen for any sound of dripping.

Check the ceilings again a few days later for any signs of mould or mildew and also check walls for streaking caused by rivulets where water from a leak has flowed down a wall. And do not forget to also check the backs of cupboards for any signs of damp.

The bottom line
Going solar is quite an expensive proposition, but it is well worth considering in light – pardon the pun – of on-going and as yet seemingly unending blackouts.

And to repeat… go for the best you can afford and do it once, rather than going cheapest – and having to do it all over again.

Panel:

Materials for solar systems, as well as smaller items such as rechargeable lamps and so on, are available at Selected Mica Stores, though some of the larger store might also stock the larger components, such as panels and inverters, required for a solar system. To find your closest Mica and whether or not they stock the items required, please go to www.mica.co.za, find your store and call them. If your local Mica does not stock exactly what you need they will be able to order it for you or suggest an alternative product or a reputable source.

1. The only place in South Africa where the Sun is ever exactly vertically overhead is on the Tropic of Capricorn around 22 December, and all places north of it. Everywhere else will experience a Sun angle of less than 90°, with Cape Agulhas, the Southern-most point on the African continent, having the greatest angle from the vertical, even in midsummer. This illustration shows how the Sun’s rays angle differs between summer (red) and winter (blue) and this, allied to differing daylight lengths, will affect the amount of power your solar panels can generate while the Sun is shining (allied, naturally to other factors such as the amount of cloud cover).
2. Four roofs with the same surface area (width and length) but given their very different slopes, great variations in the amount of Sun energy to which they are exposed.
3. This is an example of a typical panel installation – in this case ten 550W panels on a tiled roof (20° slope).
4. The 8kVa inverter.
5. The inverter readout provides detailed information on the various functions… top left shows the output from the panels, lower left shows the battery levels and discharge, top right shows power being fed in from the grid (0kW, great!) and bottom right shows current consumption. Above the display are four diodes. The three on the left (DC, AC and Normal) when glowing green indicate operation is normal. If the right-hand (Alarm) red diode lights up it indicates there is a problem and you need to call for technical assistance. Naturally, depending on the type of inverter, the various displays and light indicators may be different.
6. The battery installation with power coming in from the panels. Just visible top left is part of the system – the DC combiner box, incorporating surge protection.
7. On the bottom of each battery is a readout showing power on and feed-in. In this case the row six constantly glowing diodes indicate the battery is fully charged or close to it; when the battery is charging, the row will be incompletely lit, with the left-hand diodes being out and a single flashing one. So at a very low charge, for instance, the three right-hand green diodes will be glowing, the fourth will be flashing, and numbers five and 6 will be out.
8. Here it shows four diodes glowing, so some way to go before the battery is fully charged.
9. And taken a second or so later, here it shows five diodes glowing, but the fifth one is flashing. Once it has a steady glow, then the sixth and last diode begins flashing and then glows steadily once the battery is fully charged. According to the flashing of the fifth diode indicates a battery charge of around 70%. Naturally the speed/rate of charging will depend on the time of day, cloud cover, the season and so on.
10. The change-over DB mounted between the inverter and the main DB in the home. The green light indicates the mains power is on (power coming in from the grid) and the red light indicates that the inverter is on.
11. It is as well to set up a warning sign to keep unwary hands away from any part of the system.
12. The power from the solar system feeds into the old, existing DB in the home.
13. The old DB had some work done to it, such as an extra earth leakage breaker and some rearrangement of the breakers, interior wiring and so on. It also had a Wi-Fi-controlled hot water geyser control installed (bottom right) that allows one to set the On/Off times or override it when extra hot water is required. This particular system cannot be used to adjust the geyser thermostat, but some – when the home is fitted with the right geyser, can also be used to adjust the thermostat without the bother of having to go up into the roof space to adjust it manually. A neat paint job to enhance its somewhat dated appearance finished off the work.
14. In the event of any problem such as smoke coming from any component, this is the main breaker; pulling it rapidly shuts off and isolates the system.
15. This is the same readout as seen on the inverter image, above, but this time on one’s phone, linked to the system via Wi-Fi… it actually can become a little addictive, frequently checking to see what the situation is as Pac-Man and his mates show what’s what. This readout has a 5-minute delay.
16. Scrolling down in the same programme brings up a graph for the past 24 hours, the red showing consumption and the blue showing generation. One can check back over previous days and even past weeks to see what the hour-by-hour trends and general pattern is and then adjust usage accordingly to optimise solar usage and reduce grid power to a minimum – or even eliminate it altogether. So you can see that by adjusting your usage to make use of the peak production time – that big blue spike – you will minimise grid use.
17. This statistic shows at a glance the monthly daily consumption (red) and production (blue). This is one monitoring system of many, but you will very likely find that they are all generally be designed to show what and how much is produced and when, and what is being consumed and how much, and when. You will note that at the top of the readout on this programme is a simple visual readout showing the general cloud cover on a particular day of the month. This statistical readout allows you to check back over months to establish a view of your historical generation and consumption.
18. This is the meter and DB prior to installation. The meter, though working perfectly well handling the grid feed and consumption, required changing to a new-technology split-prepayment meter.
19. This is the new PV compatible prepaid meter. Loading pre-paid units on to it is slightly different to that required for the old meter, but still very simple. A big plus is that the readout is now to 2 decimal places. So whereas the old meter would indicate, say, 709.3 units, this meter is far more precise, and would indicate, say 709.32 units. So keeping track of what power you are using is now far more precise and measurable. Nice! But just to clarify, this is not the meter required if you will to sell power back to the local authority… it is still strictly a pre-paid meter, but is an updated, PV compatible and more precise model. As mentioned in the text, this installation, depending on what arrangement the City/local authority has set up, may be free if you will have or have solar installed. I suggest get hold of your City/local authority electricity department before doing any of the initial work of selecting a contractor to confirm 100% exactly what is required, when it is required and in what order the various approvals etc need to be sorted out. This will avoid any nasty letters arriving in your email inbox – followed by a letter, to the same effect, by registered post thereafter. Failure to have all your ducks in a row could result in you having to have your solar system disconnected until such time as it has received final approval. In the case of the City of Cape Town, when the system is disconnected a Certificate of Compliance (COC) must be provided to the relevant City authority. Failure to have it disconnected could find the City doing it for you, with a cost, possibly with a penalty as well (possibly in the range of R5500-R6500 or so, depending on whether your system is single or three-phase), and then a reconnection cost thereafter, once the approval is through.
20. One sign of a leak is streams of water running down the wall, as shown here. In this case, you might not hear any “dripping” sounds, but the evidence is there.
21. This is an absolute giveaway… mould or mildew. Remember, as with ANY leak, there is NO POINT cleaning this off and painting over it without sorting out the leak first. Doing so simply results in the unsightly stains reappearing. Once the leak has been fixed, the mould/mildew is removed by cleaning it with a household bleach solution or raw bleach and once the surface has dried, it is painted over.
22. There the flashing has been applied up on the roof, up and over the barge board, to ensure a complete fix to the leak issue.
23. Here is the completed job. Over time the flashing will fade to match the roof tiles more closely, but even if it does not finally achieve a perfect match, the big issue has been fixed. In any event, the repair is not an eyesore.