The Truth About Alternative Energy

To be a solar energy owner is having the satisfaction of utilizing one of natures greatest resources, being self sufficient and contributing in cleaning up our earth. Alternative energy has become low cost, low maintenance that pays you back over time. Eskom and municipalities will raise electricity tarriffs each year but your solar energy will not cost you a cent more.

According to the South African Department of Energy, “Most areas in South Africa average more than 2 500 hours of sunshine per year ... with an average solar-radiation level range of between 4.5 and 6.5kWh/m2per day. This is incredible as it is one of the highest harvesting countries in the world and something for the South African market to take advantage of!"

When Alternative Energy Contractors installs your solar system, we will allow for winter's short days, rain and cloud. We are licensed electrical contractors, registered with the Department of Labour and the Electrical Contractors Association of South Africa. Every installation will be issued with a Certificate of Compliance (CoC) that can be submitted to your insurance company and local authorities.

The most frequently asked question for Alternative Energy Contractors is “How long is the payoff?” Depending on the system you select, average payback is from 6.5 years to 12 years. If you are tired of electricity hikes, outages and want to be more self sufficient then Alternative Energy Contractors would love to discuss a system to suit your needs and budget. Furthermore, installing a solar system for your enterprise is encouraged by SARS and your solar system costs will be tax deductible.

 Most houses that will use solar energy in South Africa run on single phase either 10.3 KW or 13.8 KW total allowable power from Eskom and your municipality. These are two very big solar systems for a homeowner. We also do not run our houses at full capacity all the time so to purchase a 10KW or 15KW may not be necessary, unless, you want to be totally off the grid. Off grid is elaborate and most homeowners will find it out of their budget. Most people we have installed for can afford from 60 to 80% off the grid. 

A more economical way is what we call a hybrid system. The Hybrid Solar System is quickly becoming the most popular worldwide. Working out your load requirements is not as important as to what you want to spend. For example; if you have a house with two geysers, you cook most evenings with electricity and you have one to two fridges (don’t forget that bar fridge). You heat your house electrically in winter whether it be just one room or two and don’t forget how your dear wife will turn on the electric blankets for you before heading off to bed. Oh I nearly forgot, we have a great life style so you also run a pool motor everyday. Your electricity will be in the region of R2000 to R3000 a month without your basic. This means you are using about 35 to 40 KW a day. On average in South Africa we have 5.5 hours (taking into account of short winter days in the western cape) of good harvesting during the day which will need to charge a battery, supply your present load and possibly feedback into the grid as another kind of storage. Even though the municipality do not pay great rates it is better than dumping excess energy especially in the summer months.

Living off the gird is a wonderful position to be in but at the same time a huge system. Plus if you in a municipal area you will not eliminate that basic charge for maintenance and upkeep of the grid. Now if you do not care about your budget we would be very pleased in obliging in designing a system for you to be off grid at the most economical price. However, most of us are not in this position so the solar market has come up with the following system.

The hybrid system is a combination of all systems. It can be off or on grid. Grid ties systems feed back into the grid especially at the peak of the day when you are not home, reducing your electricity bill by feeding back what you do not use.

E.g. My total usage per day is 35 KW, I installed a 5 KW Hybrid on grid system. Although I have 6.8KW in solar panels I will only produce 5KW. Remember solar panels are rated for the absolute best conditions, tilt angle, direction and temperature which is 25 degree celsius. Anything above or below means that the panels are less efficient. In summer I am harvesting from 20 x 340 watt panels, 35KWH per day. So no electricity bill that day? Not so fast. You use 35 KW throughout the whole day, you have only been producing for 12 hours, therefore you have 12 more hours of solar that needed. We overcome the problem with one of two ways. Firstly, we can store the energy when the solar is producing for use later in what we know as a battery. Secondly, we feed back into the grid and use the excess later. Winter becomes more of a problem and at best you are only producing for 4 to 6 hours during the day.

Municipalities across South Africa have all agreed on a standard by which they will give credit for energy feedback by "Small-Scale Embedded Generation" SSEG. Feedback is like having another battery for those raining days or short winter days and energy demand is at a peak.

Your electricity bill then would only be what you use over and above what the solar system provides and of course what the municipality charges you for availability which is the monthly rental that you see every month whether you switched anything on or not. 

Grid tied is more economical since it has no batteries but on the other hand when the electricity goes off you are also off no matter if you are producing from the solar panels or not.

Off Grid is a system that will not feedback into the grid which depends on the solar panels and battery. Once you are suppling load and battery sufficiently, the rest gets dumped which is a waste.

In conclusion then the amount of power that is required is the amount of appliances you would like to run and for how long when the electricity is off. The Hybrid Solar System can run with any size load but the back-up is the determining factor. The only other factor is how much electricity would you like to save?