iSolar Solutions

Info in Layman's term :

What is DC and AC?

* DC - Direct Current is electricity generated by solar panels

* AC - Alternating Current is the electricity used in homes 230V How do we get DC to work as AC in our homes?

* An inverter system converts the DC (direct current / sun power) from the solar panels to AC (alternating current) as electricity to be used in our homes

What are the components in a Solar System?

Also descripbed as a Solar PV System (Photo Voltaic)

1 - Solar Panels (Mono or Poly panels - to be explained a bit later) with mounting and raking equipment

2 - Batteries - choice of lithium, deep cycle, GEL, lead-acid etc

3 - Inverter - comes in different sizes

4 - Charge Controller - also known as MPPT - control the electricity flow in your system

5 - Wires - allow electricity flow

6 - Switches - several switches to isolate certain parts of the system

7 - Monitoring screens - gives you detailed information

1. SOLAR PANELS

Generally used is the MONO or POLY panels.

Mono stands for MONOCRYSTALLINE and poly stands for POLYCRASTLLINE. Mono Panels are made from single crystal of silicon (mono = single) Poly Panels are made from many silicon fragments melted togehter (poly = many)

MONO panels :

* Are black-ish in colour

* Have 8 sides

* Are generally more expensive

* Produce more power and ideal when your roof space is restricted

* Perform slightly better in heat and lower light intensities

* More expensive choice

POLY panels :

* Are blue-ish in colour

* Have lower efficiency compared to mono panels

* Mostly used panels at this moment

* Have a lower price tag

Which Solar Panel to choose?

* Colour preference : Black or Blue

* Restricted roof space : Mono Panels are more efficient

* Budget restraints : Poly Panels are the cheaper choice

* There are other factors that might influence this choice and will be addressed by our installer

2. BATTERIES

A solar battery bank will store energy that’s produced by your system, allowing you to use it later.

Then, when your unit is not producing any energy (for instance, after dark or on cloudy days), you can tap into those energy reserves in your solar battery bank.

The more solar energy stored, the less energy you’ll have to purchase from your local municipality / utility company.

Capacity refers to the total amount of electricity you can store in your battery.

By combining multiple batteries (stackables), you can pool their collective storage capacity so that you can store a higher amount of energy.

The most commonly used batteries for solar panels today are lithium-ion batteries.

Lithium-ion batteries are appealing due to their density, high DoD and long lifespan.

Lead-acid batteries are what you most likely associate with a common rechargeable battery. This technology has been in use for hundreds of years. Lead-acid batteries offer less than their lithium-ion counterparts due to their low density, shorter lifespan and slow charging.

* The typical solar battery lasts between five and 15 years. What this means is that you’ll need to replace your battery at least once during the long life of your solar panels, which tend to hold up for 25 to 30 years.

* The number of batteries required are based on the energy needed as well as the capacity of each battery. The higher capacity a battery has then fewer total batteries you will need.

3. INVERTER

What does the inverter do – the simple explanation of an inverter is to convert DC (direct current / sun power) to AC (alternating current) in order for us to use it in our homes.

Solar inverters are the brains of the plant controlling electrical feed from the panels and charging the batteries.

Some solar inverters can also be used as a backup system without PV panels and charging batteries from the grid.

With this type of inverter as a backup you have the option of adding panels later.

Inverter AC output can be pure sine wave or modified sine wave - we concentrate on PURE SINE WAVE as pure sine wave inverters are better suited for sensitive equipment and can prevent damage to computers.

Your inverter should have a rated capacity greater than that of the peak load it needs to run - if you are going to use an inverter rated for 3kW and you try to run a 5kW load even for seconds the inverter will shut down or even sustain damage.

4. CHARGE CONTROLLER or MPPT

A Charge Controller or also known as a MPPT (maximum power point trackers), is connected between the solar panels and battery.

Its job is to regulate the battery charging process and ensure the battery is charged correctly, or more importantly, not over-charged.

Think of a solar charge controller as a regulator.

It delivers power from the Solar Panels to system loads and the battery bank.

When the battery bank is nearly full, the controller will taper off the charging current to maintain the required voltage to fully charge the battery and keep it topped off.

By being able to regulate the voltage, the solar controller protects the battery. The key word is “protects.”

Batteries can be the most expensive part of a system, and a solar charge controller protects them from both overcharging and undercharging.

5. WIRES

The correct DC wire sizes in your Solar system is essential for both performance and safety reasons.

Just like it is easier for water to flow through a thicker pipe, the the thicker the wire is - the easier it will be for large electricity currents to flow through it.

Shorter hoses and wires have a better flow than longer hoses and wires, which have more resistance.

There are 3 categories of wires in a solar system :

* between batteries and inverter

* from solar panels to charge controller to batteries

* from inverter to the grid

For each category you will have to use the appropriate amperage, cable length and accepted voltage (and power) loss.

6. SWITCHES

* There are several switches in a Solar system

* These switches allow you to manually switch off either DC or AC current for safety reasons when maintenance on the system are underway

* Automatic switches will turn the system off in case of electric faults

7. MONITORING SCREENS / SYSTEMS

* Performance monitoring screens / systems provide you with detailed information about the performance of your solar panel system.

* The monitoring system will give you info in order for you to measure and track the amount of elictricity your system produces on an hourly basis