Recognising a need for backup solutions for our clients due to Eskom load shedding in South Africa, with our extensive electrical background, access to major electrical suppliers at wholesale prices and our directors past training in Solar energy, it was at this point where preparation and opportunity met.
BUNTIGRAPH ELECTRICAL 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, BUNTIGRAPH ELECTRICAL soon established which brands and components were best suited to deal with our current load shedding circumstances as well as equipment that is scalable to accommodate future degradation of our electricity supply.
Established in 2018, interest in solar energy, at the time of establishment was not what it is today.
Although Eskom was already heading 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 realised that they could not depend on Eskom to provide 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.
Buntigraph Electrical
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 one that can not only service your current needs but also one that is scalable to accommodate your needs in the future.
Sunsynk and Deve hybrid inverters
Both these inverters are superior brands. They are suitable for residential and commercial use, maximizing self-consumption rate of solar energy and increasing your electricity, which will be provided to the loads initially. Then, the excess energy will charge the battery via SUN3.6/6K-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.
An inverter is a long-term investment. When choosing an inverter, consider the following:
There are many brands appearing overnight and "hopping on to the crisis energy bandwagon", as they say. Most inverters are rebranded Expert type inverters known as "clones." They are mass-produced and sold in 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 lifespans 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 expert type inverters are Mecer, Synapse, Five Star etc. Superior brands such as Deye and Sunsynk have 5 to 10 years warranty.
Inverters
Flooded Batteries - Gel Batteries and Lead-Acid versus 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 daylight 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) allows 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 BUNTIGRAPH ELECTRICAL's preferred battery type). 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 load shedding 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 lifespan.
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 load shedding circumstances. They are also very comfortable with deep discharging. Lithium-ion also has a much longer lifespan with most manufacturers offering a 15-year design lifespan.
A good example of lithium-ion batteries in action are our cell phones. We can use our smartphones 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 car's 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.
Solar Panels
Typically made of three elements
01
02
03
Boron (providing a positively charged layer).
Phosphorus (providing a negatively charged layer).
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 either in 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.
Typically made of three elements
- Monocrystalline
- Polycrystalline
- E.R.C
- Thin film for domestic PV solar applications, we usually only focus on Mono and Poly, however, let's have a brief discussion on the characteristics of different types of solar panels.
Efficiency of the various types
- Monocrystalline: 13% to 20%
- Perc: 26%
- Polycrystalline: 14% to 16%
Solar Panel Orientation
(The direction that your solar panels face). In Cape Town, the ideal orientation that will maximize 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 allow 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, Utilizing both the east and west facing roofs simultaneously has an alternative benefit. Using an 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 and west respectively, but the result thereof is a longer day of production than when installing only on the north face.
Result:
North facing is cost efficient with peak solar yield using one array.East and West facing requires more solar panels on two arrays but results in a longer day of solar production.
Preferred Brands
Each of our preferred 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.
