Power when you need it
Generators continue to offer the best kilowatt per rand energy alternative. Choosing the right generator and connecting it to your home safely will depend on your requirements. In order to make an informed purchase decision, you should familiarise yourself with the different types, what they require and have a good understanding of the advantages and disadvantages.
The three major types of generators
These are the most common generators on the market because the initial purchase price is lower than others based on kilowatt per rand. These types of generators are also quite economical to run. Noise levels can be an issue with open framed designs, but if the generator is stored in a proper location, noise levels can be reduced. You will find this particular generator has either a pull or electric start, and some have a built-in automatic voltage regulator (AVR) unit to help smooth operation and provide power as required.
These generators are favoured when a larger amount of electricity is required. This is because of their low revving and robust construction. They are more fuel efficient than their petrol counterparts, but are less portable due the extra weight of the engine block. This is due to the extra reinforcing needed to house the extreme compression forces generated by diesel combustion cycles. The high compression also means that extra steps are taken during the manufacture of a pull start version.
These generators feature a decompression switch, which is activated before each start, otherwise a lot of physical effort is required to start them. You will find that their initial rand per kilowatt value is quite a lot higher when compared to equivalent petrol generators. With diesel, the noise levels are extremely high and, as such, most units are encased in a cabinet with sound deadening material.
Pure sine wave generator
A pure sine wave inverter reproduces a waveform through the use of advanced internal circuitry. According to online social business developer for L&G Tools Deeren Naik, it provides the best waveform for all AC electrical appliances. “Unlike the more common modified sine wave generators discussed above, which may cause irreparable damage to the more sensitive electrical goods, the precision of pure sine wave inverter technology ensures its power delivery is closer to ‘outlet power’ more than any other generator design,” he says.
In terms of kilowatt per rand value, these rank higher than their equivalent petrol units, but still less than the diesel units. Most common units and sizes found on the market are equipped with a pull starter. This is done as a costing practice by eliminating the battery and starter electronics. This also enables the generator to occupy a smaller and lighter footprint.
Advantages of pure sine wave generators
• Prevent crashes and glitches in computers.
• Reduced audible noise in fans, fluorescent lights and electronic gear.
• Microwave ovens operate properly, quieter and cooler.
• Some appliances such as variable speed drills and bread makers will not work properly without pure sine wave power.
• They can be electronically protected from overload, over voltage, under voltage and over temperature conditions.
Single- and three-phase power in generators
Generators produce either single- or three-phase power. A single-phase generator is ideal when you have no motors running at more than five horsepower. For motor starting and running, a three-phase generator is preferred.
Single-phase power should be suitable for standard homeowners as it can produce 120V or 240V. A three-phase model produces 120-280V or 277-480V. Low-voltage units should not be considered when running appliances such as stoves, heaters and other motors.
What size generator do I require?
This is the most common question asked by potential buyers. A few years ago, when the first blackouts occurred, there were many panic buys. This resulted in incorrect purchase decisions being made. It was also because people wanted every single item in their household to run off the generator they bought. This resulted in many generators running well past their output ratings, causing burnt out coils and severe damage to the power supplying technology. It is important to remember that items that contain heating elements such as stove tops and heaters should be replaced with gas units in the event of a blackout. This is a more cost-effective solution and reduces strain on the generator.
In order to approximate power requirements accurately, take the following into consideration: Firstly, note that 1 000 watts is equal to 1kVA. To calculate your power needs, add up the wattage of all items in your home that require power, and compare it to the generator’s rated output (not maximum). This will ensure there is provision for any unforeseen power draws. Products such as fridges and air conditioners draw more power in order to start, therefore use a factor of 1.5 x product draw in order to compensate for this (1.5 x 2 000W = 3 000W). The rated power of a generator is usually written on the body of the technology.
How to safely and legally have a generator connected to your home
Installing a generator to your home’s electrical circuitry is not a DIY task. Only a qualified electrician, electrical contractor or other qualified professional has licence to complete the connections. You must ensure that you receive a Certificate of Compliance (COC) from your installer once the job is done. This certificate is important as all municipalities require it by law and an insurance company can refute a claim if your house burns down and a generator is installed without a COC.
When connecting appliances to the generator using an extension cord, follow these steps:
• Use heavy-duty extension cords that are specifically designed for outdoor use.
• Make sure the wattage rating for each cord exceeds the total wattage of all appliances connected to it.
• Use extension cords that are long enough to allow the generator to be placed outdoors and far away from windows, doors and vents to the home or to other structures that could be occupied.
• Check that the entire length of each cord is free of cuts or tears and that the plug has all three (or four) prongs.
With load-shedding a frequent occurrence throughout the country, it is no surprise that many people are buying a generator as an alternate energy source.
By Aarifah Nosarka
As in 2008, current load-shedding schedules, continuous ‘scheduled maintenance’ and transformer failures have left homeowners annoyed. At the same time Eskom is struggling to contain ongoing delays and labour unrest at the Medupi Power Station, which was supposed to be completed years ago and has cost much more than originally budgeted. With little reaction from government it seems that our
energy situation is unlikely to change any time soon.