EFI Solar Energy and Inverters.

Efi was established in 2012. With an established background in electrical contracting, servicing major construction and development companies in Cape Town, EFI was started as a tributary branch of Kamish Electrical . EFI, catering to minor electrical and security market quickly established itself as one of the leading electric fence installation companies in Cape Town.
Our Director , Y.Kamish, took interest in Green Energy in 2014 , attending numerous training courses in photovoltaic electrical and green solar energy generation in hopes of one day pursuing this new avenue.

Interest in solar energy, then was not what it is today. Although Eskom was already headed for disaster, the extent of the problem was always “swept under the rug,” and South Africans were under the impression that they had a fairly stable grid.
It was not until the advent of load shedding that South Africans realized that they could not depend on Eskom to provide a stable electricity supply to meet the growing electricity demand. Coupled with the rising electricity costs, it was clear that solar energy was the only way to go.

Recognizing a need for back up solutions for our clients due to Eskom loadshedding in South Africa , with our extensive electrical background , access to major electrical suppliers at whole sale prices and our directors past training in Solar energy, it was at this point where preparation and opportunity met.

EFI then officially branched out to solar Energy and Inverter solutions.

Having gone through many trials and errors with different brands of solar and hybrid inverters systems, batteries and solar panels, EFI soon established which brands and components were best suited to deal with our current loadshedding circumstances as well as equipment that is scalable to accommodate future degradation of our electricity supply.

Why solar?

There are many different ways of generating electricity, such as wind turbines , hydro electrical,  kinetic, and solar or photovoltaic electric energy.

Why choose solar? All other forms of electrical harnessing or harvesting require the use of turbines ( wind turbines,  wind mills , hydro turbines etc)  however,  all of those options require moving parts, and as with any moving parts, they require ongoing maintenance . Solar panels are stationary,  having no kinetic energy,  meaning no maintenance besides a rinse now and then to remove dust build up. Solar produces no noise and utilises roof space which is usually unutilised space .


An inverter is the main key component of any backup or alternative power solution. There are many different inverters on the market. When selecting an inverter,  we advise that you find an inverter that can not only service your current needs but also one that is scalable to accommodate your needs in the future.  Most clients focus only on their current needs, however,  taking into account the situation that we find ourselves in with Eskom at the moment,  a client that may be convinced that they are only looking for a “back up only solution” at a particular time , may be faced with a situation later when our electrical infrastructure breaks down further and they do not have the option of going solar because they have opted for an inferior brand of inverter that is for example : not recognized on the City of Cape Town’s approved list of inverters .

Sunsynk & Deye hybrid inverter,  suitable for residential and commercial use, maximizing self-consumption rate of solar energy and increasing your energy impendence.   During the day, the PV system generates electricity which will be provided to the loads initially. Then, the excess energy will charge the battery via SUN 3.6/6K-SG. Finally, the stored energy can be released when the loads require it. The battery can also be charged by generator to ensure uninterrupted supply in the event of grid blackout.

Equipped with RS485/CAN port for battery communication.

When selecting an inverters , make sure they meet the following criteria. 

  • Make sure your inverter is made by an established , reputable brand with a decent warranty/ guarantee.

An inverter is a long-term investment.  There are many brands appearing overnight and ” hopping onto the  energy crisis bandwagon,” as they say . Most inverters are rebranded Axpert type inverters known as “clones.” They are mass produced and sold by various distributors,  rebranded with their respective names printed on them. They are cheaply made and claim to tick all the boxes on face value, however,  they have short life spans and despite working well as a UPS ( uninterrupted power supply) as a load shedding solution,  they perform poorly with the addition of solar.
Most popular brands have a 12 – to 24-month warranty.

Examples of axpert type inverters are Mecer, Synapse , Five star etc.
Superior brands such as Deye and Sunsynk have 5 to 10 years under warranty.

  • Make sure the  inverter you choose is approved on the City of Cape Town’s approved inverter list for solar.  A quick Google search will direct you to a link or this list. If your inverter is not on the City’s approved inverter list, your application for solar or SSEG( small-scale embedded generation ) at a later stage will not be approved. You will not be able to scale your system or legally upgrade it to solar.
  • Make sure your inverter has the ability to blend power and is a ” True hybrid inverter”.
    Most inverters claim to be hybrid inverters because of the fact that they can switch between AC ( alternating current) and DC
    (Direct current) automatically and also that they can accept solar power and invert such power from DC to AC power.

A true hybrid inverter can not only do what is stated above but also simultaneously blend solar, DC, and AC power simultaneously.

For example:

On a partly cloud day , a particular household may require 1000 watts of power to operate.

If there is sufficient solar power available from the sun,  the inverter will be running the house completely on solar energy.

If a cloud was to pass and block the sun sufficiently to block most of the sun and the inverter was not able to harvest that required 1000 watts from solar, an inferior inverter would then simply switch to Eskom / utility power .

If you were using a superior  True Hybrid inverter  such as the likes of Deye or Sunsynk, for example, the inverter would use what is available at that given time from solar and only supplement its needs from Eskom , thus maximizing solar and minimizing utility draw from the municipal supply. It will actually blend power from different sources so that even on a cloudy day, it will use even the least bit of solar available and make up the difference from Eskom.

This is what is meant by blending power. This is a unique capability and achievable only by using a true hybrid inverter .Remember, they all claim to be hybrid inverters, but it’s the blending capability that sets them apart.

  • Make sure that the inverter is a Smart Inverter with a smart mobile application . This means that you should be able to view your performance , your solar yield and history from your phone or PC .

This is highly recommended as this will enable you to :

  1. Monitor your battery usage to better manage your resources.
  2. Monitor solar production and consumption to optimise utilisation of energy as well as adapt your behaviour to optimise solar.
  3. Get live support from your installer or supplier .

Make changes to your system remotely.

Picture: Volta,   Sunsynk and Hubble lithium ion batteries .


Flooded batteries – Gel Batteries and lead acid VS Lithium ion.

To be clear, a solar inverter system can operate without a battery.
A solar system without a battery will merely use solar during the day light hours and municipal power at night. This is very useful for energy and cost saving during daylight hours

A solar array ( set of solar panels ) will only draw what power is needed as it is being used simultaneously .

A battery allows power to be stored, and in solar terms, we refer to batteries as storage.  i.e Energy storage.
Batteries allow you to store power for use at a later stage, at night or when using a Pure hybrid inverter ( with blending capabilities) allow you to use power when solar is in short supply and blend with municipal power for immediate use.

There are various types of batteries available. Mainly, gel and lead acid are commonly referred to as “flooded batteries” and then, of course, Lithium ion. ( Lithium ion is EFI’s preferred battery type)

Picture : Gel batteries most often take the shape of typical car batteries as depicted above.

While flooded batteries have their place in certain applications, for example , they can discharge large amounts of power quickly making them ideal for starting cars and machinery, however,  even though referred to as deep cycle batteries,  are not  ideal for deep “cycling” which is necessary for solar applications as well as loadshedding applications.
Flooded batteries prefer to use only the top 30 % of its available power at a time and when discharge is deeper than 30%, it significantly decreases their life span.

This is where Lithium ion technology comes to the forefront. Lithium Ion , while not being perfect for fast discharge like their flooded battery counterparts,  they excel in the realm of slower discharge at slower rates and for long periods of time , for example , solar and loadshedding circumstances  . They are also very comfortable with deep discharging.
Lithium ion also has an much longer life span with most manufacturers offering 15 years design  lifespan .

A good example of  lithium ion batteries in action are our cell phones. We can use our smart phones until they are flat and die and simply recharge them without any concern of battery damage. However, if we did this with our motorcar’s batteries, we would quickly damage the cars battery cells and need to replace them after a very short while.

Over the years we have  installed many different brands of batteries and have narrowed down our selection to only  a choice few brands.

Factors to consider when selecting a battery brands. 

  • Is there Local support?
  • Is this an established and reputable brand?
  • Guarantee period ( sneaky fine print and exclusions.
  • Life expectancy or design lifespan.

Solar Panels

Solar panels come in many different sizes and variants.
Although any type of solar panels will technically work with an inverter, they are not all created equally.

Solar panels are typically made of 3 elemental layers. 

1. Boron ( providing a positive charged layer).
2. Phosphorus ( providing a negatively charged layer).
3.Silicon. providing a semiconductor layer sandwiched in between the two.

They are layered together to form a solar panel. Inverter systems combine multiple solar panels in either series or parallel configuration to make up a solar array.

When the sun’s rays hit the solar panels, protons and electrons are charged and discharged in their respective layers resulting in movement of electrical charge through the silicon layer known as electrical current. This electrical current or power is then harnessed and drawn to the inverter which then ” inverts ” this power into  stable 220 volts as standard voltage for immediate use in our homes or business and the excess to be stored in batteries for later use.

This process is known as a Photovoltaic reaction producing photovoltaic energy.

Variants of solar panels include:

  • Monocrystalline
  • Polycrystalline
  • E.R.C
  • Thin filmFor domestic PV solar applications, we usually only focus of Mono and Poly, however , let’s have a brief discussion on the characteristics of different types of solar panels.


Monocrystalline panels , so named as they are made from a singular or pure crystal silicon cut into pieces. Easily identified by their dark blue appearance and mono colour tone.

“Mono solar panels”  are super long lasting due to their pure silicon make up as silicon is highly durable. They are also very efficient , requiring less surface space than it’s polycrystalline counterpart.

The downside of Monocrystalline panels is that because of its singular crystal make up, the manufacturing process of cutting singular Monocrystalline cells results in a lot of wastage of silicon material and this results in a higher price tag.

Polycrystalline solar panels.

As per our description above of Monocrystalline solar panels , Polycrystalline solar panels are actually made of the same silicon material, however,  rather than being made from a singular or “mono” silicon crystal,  they are made from a blend of silicon crystals melted together and poured into moulds. This means less wastage in their manufacturing process making them significantly cheaper to produce

The downfall of polycrystalline solar panels however, is that because  they are not pure silicon, they are less efficient and requires more space to produce similar results when compared to Monocrystalline solar panels . This makes Mono better suited for domestic roof top installations where space is limited and polycrystalline panels more economical where space is abundant . Polycrystalline panels are also less heat tolerant than Monocrystalline solar panels and produce less solar energy in high heat conditions.

Perc Or Bifacial panels.

Perc stands for passive emitter and rear cell.
These solar panels are almost the same as Monocrystalline (Mono solar panels)  with the added benefits of being able to capture more photo voltaic energy from both sides by having an additional passivation and reflecting layer on the underside of the solar panel . It thus performs better than mono and poly solar panels and requires less space but is significantly more expensive.

Thin film solar panel cells.

These are solar cells usually installed as thin films of solar harvesting material . it is usually installed and constructed on site by a specialist and resembles a sticker rather than a solar panel. It can conform to different sizes and shapes and takes the form of whatever it is applied to. Although effective , the result is not standardised and is not commonly used in South Africa.

Efficiency of different types of solar panels.

Monocrystalline: 13% to 20%
Perc: 26 %
Polycrystalline: 14% to 16%

Thin film : Varies

For South African domestic and commercial market, Monocrystalline solar panels are by far the most popular and usually our first choice.

The brands that EFI makes use of are listed below:

  • JA Solar
  • Jinko solar
  • Canadian solar
  • Trina solar
  • Longi solar
  • LG solar

Each of the above brands have fantastic guarantees and linear performance guarantees with proven performance .  They all provide tier 1 level  guaranteed performance  and have earned our trust in the solar industry.

Panel orientation.

When installing solar panels on a typical domestic solar installation,  there will most likely be multiple solar panels used. Where we  install these panels together in a row or group , this is referred to as a solar “array “.

The solar panels installed in any particular  array must be installed with the following criteria.

  • The panels must be the same size.
  • The solar panels must be of the same brand.
  • They must be installed facing the same orientation.
  • None of the panels in the array should experience shading or shadows across the face of the solar panels.

NOTE. Most solar inverters only allow for one solar array. One of the main reasons EFI solar energy and inverter solutions use the Deye and Sunsynk range is because of the fact that these inverters come with 2 x independent solar charge controllers .

This means that one can install 2x different types of solar panels on two different orientations and of two different brands at the same time on the same inverter.  This is ideal when a client upgrades their system to add more solar panels at a later stage.  If a particular solar panel is discontinued, another brand or type can be used on the second array.

Solar panel orientation.

(The direction that your solar panels face).
In Cape Town , the ideal orientation that will maximise solar yield production is 27 degrees facing north.

Rarely do we find that roofs are perfectly north facing or angled at a perfect 27 degrees.

There are mounting structures available that allows us to angle the panels to face north and adjust the angle of tilt , however we seldom use them as they have various downfalls such as catching wind and making the panels susceptible to wind damage. They also add significantly to the cost.

One must also consider that although north has the longest sun exposure,
Utilising both the east and west facing roof space simultaneously has alternative benefit.

Using east west orientation allows the panels in the east to capture the rising or morning sun and the west to capture the setting sun and at mid-day , they capture both simultaneously.

We do have to compensate with a few extra panels and split them across both available charge controllers of our inverter , east west respectively  , but the result thereof is a longer day of production than when installing only on the north face.


North Face: Cost Efficient with high peak solar yield using one array.
East and West: More solar panels required  on two arrays but  results in a longer day of solar production.