Category: Solar

Questions Asked Regarding Home Solar Systems

For those looking for an alternative way of powering their homes in South Africa, consider home solar systems.

Thing is, how exactly does a home solar system work?

• A PV – otherwise known as a Photovoltaic Solar System. PV consists of solar panels, racks for placing the panels onto your roof, an inverter and wiring.
• From sun-up to sun-down the solar panels generate electricity which is transmitted to an inverter.
• The inverter in turn then converts this DC power into AC (Alternating Current). AC is the standard used in most households.
• AC power is then delivered directly to the main electrical service panel of your home.

Another oft-asked question is; how long will your solar system last? First let’s ask another question before the answer. Are you in for the long or the short-haul?

Systems can last anything from twenty five to forty five years. Some have been known to last even longer than this.

Does shade and grey days affect the efficiency of your home solar system?

Because solar operates at optimal output when the sun shines brightly. Shading could prove to be an issue.

Unlike the early days of solar power when systems had to be sized for peak loads, a grid-connected PV system will seamlessly switch to draw from the utility grid when power is required.

Your solar system has been designed with an annual production target; in other words it has been specifically created to average out sunnier days with cloudy days; a win-win set-up all round.

Will the value of your home be augmented by installing a home solar system?

Home Solar System

Many people in South Africa is making use of home solar system to generate power.

For example, in Alexandra Township in Johannesburg, houses are being fitted with solar panels for hot water geysers. As is the case with many low-cost housing developments like these. 

These might seem to be expensive to install at first. Solar power will however save you a lot of money in the long-term.

Power Inverters

The internal working parts of power inverters and UPS, inverts the incoming DC voltage into sinewave waves. Due to the complexity of these parts, the result would be that investing in power inverters could prove to be a costly exercise.

Incoming sine waves have been re-created to save costs and protect equipment. Modified sinewave inverters as well as UPS systems simply switch from the DC supply between positive and negative poles. This will offer you a simulated sinewave wave.

Modified sinewave inverters and UPS systems are inexpensive to manufacture. But could be very costly if these are installed into the wrong equipment.

Anything with a high inrush or high-speed control should be connected to the correct power inverters to avoid damage. The same for equipment with sensitive data.

It is imperative to take special note that certain UPS systems. Most particularly the 600 VA which falls under the desk-type UPS systems. They are classified in the modified sinewave categories. Because computers only run off power inverters for short periods of time when power outages occur. They are far less likely to be damaged from modified wave forms.

Different Inverters

For those that don’t know the difference. There are certain distinct advantages of pure sine wave power inverters over modified sine wave power inverters. We make use of energy every single day of our lives and in every single aspect in a modern world. In South Africa electricity supply is barely keeping up with the pace and demand. Coal-fired power stations are experiencing issues plus they cause pollution in an already-polluted world.

But there is hope on the horizon, such as using and installing a home solar system. Making use of the abundant sunshine we are so lucky to have in South Africa.

Leveraging the Sun

The sun is a significant font of energy without which no life would be possible on Earth. The energy from the sun can be used to generate electricity in a more sustainable and pollutant-free process. More so than coal-fired power stations that are at present generating most of our energy.

But heating water through the use of solar power is certainly not new to man. The ancient Greeks, for example, were building houses in ways that the sun could heat them during cold winter months.

Solar or photovoltaic cells are specifically designed to capture the rays of the sun and directly convert them into electricity. Furthermore, solar cells have been used for many decades to provide power to satellites, too.

A solar cell consists of two thin plates made of a semi-conductive material such as silicon with a layer of chemicals on their surface. When sunlight falls on the cells, electrons are released from the silicon and they move over the layer of chemicals, generating an electric current.

South Africa has among the highest levels of sunshine in the world. But very little has been done to use its power to generate electricity. When Earth’s fossil fuels are exhausted, scientists believe solar energy to be the only alternative.

It has been predicted that more than 2.5 % of the world’s electricity needs will be provided by solar energy by 2015.

Installing a home solar system this summer is perhaps one of the most practical ways forward.

Solar Battery Power and Solar Panels

For individuals and businesses that are not too sure how Solar Power function. Please read below how using Solar Panels and Solar Batteries together can be of benefit.

Solar Panels, together with inverters produce power in proportion to the Solar Energy from the sun. This energy is then converted into electricity. When appliances utilise power the Solar System subsidises this demand. If the Solar System has excess then the surplus is exported to the utility grid.

Adding Solar Batteries to the equation means that you now have a place in which to store the surplus solar energy.

This excess energy is usually stored until it is need which is usually at night or on cloudy days when there is little solar input.

The inverter manages the flow of the power to ensure that you maximise the use of this free solar energy. The inverter also ensures not to waste any surplus electricity.

So in other words, a solar battery is in effect a storage unit where all the excess energy which is generated during sunshiny days is stored.

As far as Solar Batteries are concerned, there is never a one-size-fits-all scenario. The best way moving forward is to ensure that your solar batteries are of a high quality.

Different solar batteries are used for varying purposes to ensure that the right product for the right application is used.

Lead Acid Batteries

• Because Lead Acid batteries contain large amounts of electrical energy, they are capable of discharging very quickly if any form of conductor is placed across their terminals.
• Lead Acid batteries contain sulphuric acid which is corrosive.
• Lead Acid batteries give off hydrogen when they are charged which when mixed with air, can become explosive and can even be ignited by a tiny spark, therefore handling these with caution is advisable.
• Lead Acid cells have a minimal voltage of about 2 V – this is all depending on the state of charge.
• A battery usually consists of several cells that are connected together in a series to produce sufficient Voltage – this is usually 12, 24 or 48 Volts.

Deep cycle cells

A Deep Cycle Cells refers to a battery being charged with energy during sunny days.

Solar Batteries, as we have deduced, are therefore vital for the optimal function of Solar Systems.

What is Solar regulators?

Solar regulators is a small box that consists of solid state circuitry which is strategically placed between solar panels and the solar batteries. Solar regulators are also referred to as a change controller.

The function of the solar regulator is to be utilised in conjunction with stand-alone systems. These can be off the grid or a grid-connected solar system that combines a backup battery bank.

A solar regulator is not required for a grid connected solar power system without batteries. Today’s technologically-advanced solar regulators are extremely efficient and will be able to out-strip any three-stage mains power battery chargers.

The function of a solar regulator include:

• The primary function of the solar regulator is to regulate the incoming charge from the panel that flows into the deep cycle battery bank.
• This is to prevent the batteries from becoming overcharged.
• Regulators can also offer direct connectivity to appliances while recharging batteries.
• This will bypass the battery bank although the batteries will be charged simultaneously.

How to choose your solar regulator

• First and foremost – it is important to check the amp ratings of your solar panels.
• Once you have tallied up the figures, this should give you an idea of the minimum size charge controller required.
• If you think your solar system will be added onto sometime in the future, it might be best to plan ahead for future growth.
• This will save you money in the long term when adding more solar panels onto your system down the line.

Explaining low voltage disconnect

Once the voltage drops below a certain point and they continue to draw power, this will cause untold battery damage.
Solar regulators should be equipped with LVD – Low Voltage Disconnect features to avoid damage.
LVD will monitor battery levels and will automatically disconnect the load that is connected to the battery if the voltage levels drop.
You need never maintain your solar regulator – although it might be a good idea to check the wire connections from time to time to ensure they are taut and free of corrosion.
It is also advisable to mount your solar regulator away from direct sunlight and heat where there is good air flow.
For safety purposes always ensure there is a suitable fuse between the solar panel and the solar regulator.
It is important to acquire a professional’s opinion before ordering any equipment.