Home

Let Solar ease your Loadshedding woes

Details

Written by: Administrator

Category: Uncategorised

Published: 23 October 2024

Hits: 716

So you getting tired of the constant power outages.

Paying for something you not getting?

There are a few options you can consider to mitigate the effect of a poor electricity grid and poor supply and I hope that this article will help answer some burning questions.

Options on offer

So lets look at Solar as this is where your interest lies.

In this space,  there are 2 types of equipment,  and comes with their own pricing and issues. 

First,  lets delve into how we get to decide on a unit before we explore the good and bad ones.

According to SANS10142-1 ( our electrical code book ),  the way we size our need is based on a Base Load and additionals.  The Base Load is based on the size of your dwelling,  not your property.   This starts at 5KW for 100sqm plus 1KW for every 100sqm thereafter.  Thus,  a 300sqm townhouse has at minimum a base load of 7KW.  If you add your geyser ( 1.5KW ), Air Conditioner ( 1x 2KW ) and Kettle ( 1.5KW ),  you now need 12KW.

I wont be adding any diversity factors into this example to keep it as simple as possible!

For your solar system to carry the base load,  based on the aforementioned power requirement,  your minimum size is a 8KW system.  If you go smaller,  you will have to manage your usage and your expectations.  For example...

3KW is what I consider the absolute minimum and will require you to become a Watt-Watcher.  You will scrutinise everything plugged into your system from the Fridge,  Microwave, Kitchen Appliance and the likes.  It is unlikely to give you much joy when using it on a Hair Dryer or a Kettle as it may trip out!

5KW will be fair and you still need to watts your usage ( yes,  it is intended ) but you have some room to breathe

Now we get to the part that makes or breaks the decision making process.

For the sake of this article,  we will stick to an 8KVA Inverter.

From what I have seen,  the industry seems to like a 4Panel configuration which is considered as being cost effective; but I disagree!

At most,  4 panels at 600W a panel will give you 2.4KW.  This is around a quarter of the capacity of the Inverter. which will give you power and charge your battery during the day.  It will save you some money if:

you use your appliances during the day! Dishwasher,  Tumble Dryer.  Washing Machine

Vacuum Cleaner,  Hair Dryer

At night,  it only costs you money.

However,  2.4KW of solar energy with full sun is hardly enough to handle all the aforementioned items.  Your Tumble Dryer itself draws 2KW,  so unless you use each item separate,  2.4KW is a drop in the bucket.

Factor in weeks where there is so much cloud cover that you hardly see the sun.,   a 2.4KW solar system will be rendered useless as your generating capacity will be cut by anything from 30% to 90%.

The only way to get around this and still have a system that works is to increase the amount of panels.  As mentioned before,  the more you spend the better it works.  By increasing the Panel count to 8,  this allows your battery to charge and carry the basic essentials in the house running without needing input from Eskom,  then it is worth the added expense.

Doubling the panel count even more from 8 to 16 will give you even more usability,  but then you may as well spend some extra money on a second battery and look at managing night time usage to make it financially viable. This will allow you to double your storage capacity and thereby your backup time which,  if managed well,  last you through the night and minimise if not eliminate the need for Eskom.

If you don't want to do much management and tweaking,  then you need a basic inverter that will give you power from battery and Solar.  This is the cheapest solution and also the least effective.  The Inverters are prone to failure.

If you want bells and whistles,  then you need to double or triple your inverter expense as the more upmarket inverters have more features and management abilities.  They also carry a longer warrantee!

I hope this answers some questions and I know it will lead to more questions.