Solar FAQ's

PV stands for photovoltaic. This is the technology whereby solar cells are used to convert sunlight into electricity.

Photovoltaic cells are made up of semiconductor material such silicon. The silicon is mixed with elements phosphorous and boron which create conductivity within the cell and activate the movement of electrons. The electrons move across the cells when are activated by the sunlight’s energy into the electrical circuit hooked up to the solar panel. Therefore, the power produced by a PV array (group of solar panels) increases with the intensity of the light striking it.

The main difference between mono-crystalline and poly-crystalline panels is the purity of the silicon. Mono-crystalline cells go through a higher filtration process producing a purer form of silicon. This is why mono-crystalline cells can conduct higher amounts of electricity within the same area, therefore be more space efficient than poly-crystalline panels, and also offer higher peak efficiency.

The solar cells in mono-crystalline panels are slices cut from pure drawn crystalline silicon bars. The entire cell is aligned in one direction, which means when the panels are in direct sunlight at the correct angle, they are extremely efficient.

Poly-crystalline cells on the other hand are made up of silicon off-cuts, molded to form blocks and create a solar cell made up of several pieces of pure crystal. As the crystals are not perfectly aligned there are losses at the joints between them, resulting in lower efficiency. However, this mis-alignment can assist in some cases, as the cells work better from light at all angles, for example in low light conditions.

Aesthetically mono-crystalline panels are favoured by customers for their black appearance opposed to the poly-crystalline panels which are bluer in colour due to light reflection.

The energy output depends on your system size. The larger the system, the more energy it generates. Additionally, the solar system's energy output depends on your location in Australia, the direction your panels are facing (with north being the best), the tilt angle, and also the day and season.

The Bradford Solar ChargePack includes SolarEdge DC optimiser technology.

Power optimizers increase the energy output from PV systems by constantly tracking the maximum power point (MPPT) of each module individually. Furthermore, the power optimisers monitor the performance of each module and communicate performance data to the monitoring portal for enhanced, cost-effective module-level maintenance. Each power optimizer is equipped with the unique SafeDC™ feature which automatically shuts down modules' DC voltage whenever the inverter or grid power is shut down. The MPPT per module allows for flexible installation design with multiple orientations, tilts and module types in the same string.

In traditional Solar PV strings without optimisers, issues such as shading on a single panel would affect the entire string equally. For example, shading 50% of one panel would reduce the entire system efficiency by 50%. The DC optimisers allow each panel to work independently, so only the output of the afflicted panel will be affected. So if one panel goes down, or is not performing well, the rest of your panels can still be working at optimal output.

All Bradford Solar packs that include SolarEdge systems include SolarEdge DC Optimisers on the rear of each solar panel.

With Bradford systems, CSR - an Australian icon for 160 years - provides the warranty. If you have problems, we are here for you. Cheaper inverters often come with a manufacturer's warranty, and if you need to claim, you have to deal with an overseas company.

Tier 1 panels are within the top 2% of Solar PV manufacturers. Tier 1 solar panels are the highest standard of panels available in the world. They only come from vertically integrated manufacturing companies, which means every stage of the manufacturing process is quality controlled. Tier 1 manufacturers invest heavily in research and development and use advanced robotic processes. To be a tier 1 manufacturer you must have been manufacturing solar panels for over 5 years. Tier 1 manufacturers use the best grade of silicon to produce solar cells. The higher the silicon grade, the longer the solar cell will last and the better it will perform. Bradford only use tier 1 manufactured solar energy products.

There are a few things which need to be considered:

• You will need to match the installed components to current equipment (panel wattage and inverter capacity);
• You will have to reapply to connect additional panels (kW’s) to the grid. This effects current feed in tariff arrangements (adjusting the system may remove your current FiT);
• If the system is older it will need to be brought up to the current electrical standard – the requirement and costs will depend on the year of install.

Overall it is typically more cost effective to install an additional system if you wish to generate more power.

Additional charges for (smart-) meter installations and/ or connection fees might apply and vary between States and Energy Retailers. Please check with your energy supplier. If you would like this to be organised through Bradford this can be arranged however charges will apply.

A collection of solar panels are electrically connected to form a string. One or more strings form an array of panels.

There are three main types of solar panels available, each of which has its own advantages. These are: monocrystalline, polycrystalline and thin film. At Bradford, all of our solar energy systems are monocrystalline or poly-crystalline as they are the most efficient and require the least roof space.

.      Mono crystalline (monocrystalline c-Si): Being used for over 50 years, these highly efficient panels produce a given amount of energy even only with a few panels. They have a very slow degradation, generally losing 0.5 - 0.7% per year.

.      Poly crystalline (polycrystalline c-Si): These panels are slightly similar to mono crystalline panels.  However their performance remains steadfast at higher temperatures, making them suitable for use in Australia.

.      Thin film: These panels have the lowest efficiency so to produce a certain amount of energy, the size of the panels must be doubled. However they tend to perform better than crystalline panels in places where there is a lot of cloud-cover or where the sun's irradiation is weaker. Research is continuing to improve the performance and manufacturing process of thin film panels.

Yes. Shading can affect the output of the entire string to be reduced to virtually zero for as long as the shadow sits there. In severe cases, a shadow does not necessarily need to fall on an entire panel. Depending on type of system installed, shading on a single cell could reduce the output of the panel and in turn the entire string (a string is a series-connected set of solar panels).

In a conventional solar panel string, shade is something that blocks the flow of the electrical current. However if there is a separate unshaded string, the string will continue to produce power as per usual.

Importantly there is a solution to shading; Bradford Solar recommends SolarEdge DC Optimisers which are included in all our SolarEdge systems. This will increase the energy output from PV systems by constantly tracking the maximum power point (MPPT) of each module individually achieving the optimal output.

Bradford will always provide you with expert solar advice, as we are members of the Clean Energy Council we must adhere to the code of conduct which stipulates we must assess whether a roof is suitable for mounting an PV array. Taking into consideration what roof space is available, orientation and tilt of the panels (this affects the daily performance of how much solar energy your system may generate) and any shading which will occur and how it will affect the system performance.

Micro inverter panels feature a ‘micro-inverter’ on each panel which convert all the DC (direct current) power directly into regular AC (alternating current) household electricity. This avoids losses from shaded strings and maximises a system’s power generation. In circumstances where one solar panel may be shaded, the rest of the string can still operate at full capacity. So if one panel goes down, or is not performing well, the rest of your panels can still be working at an optimal output. This is because each solar panel works independently.

This means it has a high rating for dust and water resistance. This is crucial to ensure that the inverter’s integrity is not compromised and that it operates for the long haul.

Solar panels produce most power when they are pointed directly at the sun. In Australia, solar modules should face north for optimum electricity production. For grid-connected solar PV power systems, the solar panels should be positioned at the angle of latitude to maximise the amount of energy produced annually.

Most Australian homes have a roof pitch of 20° to 30°. If your roof's slope is not ideal, our solar installers can create an appropriate mounting frame to correct the orientation and elevation of your panel.

The best position to install PV panels is on a roof plane which is facing closest to true north. Facing closest to true north optimises the exposure of the solar panels to the path of the Australian sun, resulting in maximum power generation.

The tilt angle of the panels is also important and is dependent on the pitch (angle) of the roof. Most Australian homes have a moderate roof pitch (angle) and this is usually suitable to the panel tilt angle required. However, if you have a flat roof, or an unusual roof pitch, Bradford Energy can supply tilt frames that allow the panels to be adjusted to the optimum angle.

In the southern hemisphere, solar arrays (one or more solar strings) should face north to collect maximum sunlight during the day. The panel tilt should be set to the local latitude to optimise the sunlight across the seasons. A north facing panel tilted to match the latitude will almost always optimise the performance.

The inverter (a critical unit as it converts solar energy to electricity) is best installed near your existing meter box; either inside or outside is fine as long as the inverter is not exposed to direct sunlight for an extended time.

Solar generates the most power when it is sunny. Heat can actually reduce the performance of solar modules. However, even on an overcast day your system will still generate about a third of the power it would generate in direct sunlight.

Yes, shading definitely affects the performance of your panels. Shade from trees, roof ventilators, or antennas changes the flow of electricity through the panel, thereby reducing the performance. To maximise their energy-storing capacity, PV panels must be in full sun from at least 9am to 3pm and must be kept free from shade, dust, and other impurities.

Fortunately, the Suntech and LG Solar photovoltaic modules used in Bradford's solar energy system are created with a bypass diode that minimises the power drop caused by shade. In homes where there are shading issues or panels have to be installed in different directions or roof orientation, we suggest you explore the AC panel – micro-inverter range. Ask us if they are suitable for your requirements.

The amount of sunlight that a solar panel receives over a day is expressed in peak sun hours. As the amount of energy generated by a panel is directly proportional to the amount of energy it receives from sunlight, it is important to install panels so they receive maximum sunlight. One of our solar energy specialists will calculate the amount of energy generated by the solar PV panel from the peak sun hours available. Peak sun hours vary throughout the year.

Solar panels operate best at ambient temperatures up to 25°C. Extreme heat can cause a solar panels output to decrease. This is due to the electrical flow of the electrical circuit changing the speed at which the electrons travel. As a result the resistance of the circuit increases due to the elevated temperature. The same result is achieved when the resistance is decreased due to extremely low temperatures.

To determine the heat tolerance of a solar panel you should refer to the temperature coefficient (Pmax). This will tell you how much power will be lost when the temperature rises by 1 degree above 25 degrees.

As like all electronic appliances solar panels can overheat. To reduce the effects of extreme heat, solar panels are installed a few inches above the roof line. This allows air to flow underneath the panels which assists the panels to cool down. This is also known as a passive cooling system. The inverter also is recommended to be installed in shady areas to avoid direct sunlight and therefore reduce the risk of overheating.

Electricity is either connected at 230 or 240 volts (single-phase, which accounts for the majority of domestic situations), or 400 and 415 Volts (three-phase). The latter is better suited for powerful appliances. A single phase connection is common in small to medium sized houses that use an average amount of electricity. Three phase connections are more common in larger houses that utilise a lot of electricity, or in rural areas.

No. The panels are tested to withstand hail. A hail test is conducted with a 20 mm diameter ice ball at 23 m/s (82km/h), directed at 11 impact locations. 

This means it has a high rating for dust and water resistance. This is crucial to ensure that the inverter’s integrity is not compromised and that it operates for the long haul.