Converting your home to green energy should be seen as investment and not an expense as you will be saving money on your utility bill each month. Costing of a solar system is unfortunately not a one size fits all. Your cost will depend on the size and type of solar system or back up system needed for your business or household electricity usage. The type of inverter, size and amount of solar panels and type of batteries will affect this cost.
Attempting to backup the entire house in the case when Eksom fails would require both a large inverter and battery. A typical budget to even attempt this is about R400k+ (irrespective of what other solar companies may promise in terms of performance of a solar system).
There are several items with heating elements (geyser (3kW), washing machine (2kW), dishwasher (2kW), washing machine (2kW)) in order for these to be backed up the size of the inverter would have to be extremely large - note that all these appliances will hang off the end of the inverter 100% of the time (not only when there is load shedding) and so the inverter must be large enough to cater fro them all. Plus the inverter must cater for the inductive loading whenver there is a single phase motor starting up (washing machine etc). As you can see, the inverter then needs to be very large and a minimum size suggested is a 15kW version (Over R70k for the inverter alone).
To limit the size of the backup battery and inverter, your electrical DB board would need to be “split” into two sections “Essential” (e.g.: food fridges, lights. TV) and “Non-Essential” (e.g.: floor heating, stove, and other heavy items). Thus a bit of electrical juggling may be required. Note that we backup on a "circuit-by-circuit" bases - so, for example, if your TV happens to be on the same circuit as say the kitchen, then further circuits may have to be pulled in order to split these.
In terms of the payback, or Rate of Return of investment (ROI) with these systems, first a solar only system (no backup) has a ROI of about 3-4 years, which in itself is not too bad. However, as soon as you include the backup part, the figures are thown out of the window and realistically the ROI then becomes about 12 years. This is helped a bit when installing a Lithium Iron battery as this type of battery can be intentionally cycled at night and then refilled by solar during the day. This might bring the ROI down a little, but it is difficult to calculate. The backup does however give you a piece of mind with respect to the load shedding. ExSolar will only quote and supply you with brands we know and trust like Victron, Sunsynk and Freedom Won. We will try our best to find a solar solution that fits your budget.