Solar Power Systems – Environmentally friendly, green energy systems
Fully qualified, accredited and licensed in solar power systems.The cost of electricity is set to rise in the future – and since we have an abundance of sun, it makes sense to harness the power of the sun in the form of solar power. It not only slashes your energy bill, but you will be doing your bit to help the environment by reducing greenhouse gases. So, if you’re looking for a solar power system in Perth, consult the experts at Solar E.
How Does a Solar Power System Work?
To understand how solar power systems work, let’s begin by looking at where it gets its energy – the sun.Think of the sun as a huge furnace that has a core temperature of 15 million degrees by fusing 620 metric tonnes of hydrogen each second. A very small part of this immense energy travels to earth in the form of sunlight. It takes 8 minutes to travel a distance of over 150 million kilometres and has been powering the world’s weather and eco-systems for billions of years.It is little wonder why people are taking advantage of solar energy; it is renewable, green, cost-effective and will never run out (not for another 6 billion years at least).
How does solar power convert into electricity?
Solar power is a system that allows the energy from sunlight to be converted into electricity.The photovoltaic (PV) cells in a solar panel are made from a semi-conductive material, like silicon. When sunlight (protons) is absorbed into them, its energy is transferred to the electrons in the cells, causing them to be more active and thus creating a direct current (DC).These panels are connected to an inverter, which converts direct current into alternating current (AC), which is the type of electricity we use in our day-to-day lives.
The science behind solar
Photovoltaic Systems make use of the solar panels converting natural light to electricity. The ‘photovoltaic effect’; (photo = light and voltaic = electricity)Sunlight is composed of photons, or ‘packets’ of energy. These photons have various amounts of energy corresponding to different wavelengths of light. When the photons strike a PV cell, they may be reflected or absorbed. When a photon is absorbed, the energy of the photon is transferred to an electron in an atom of the cell, a semiconductor based material (such as silicon). With its newfound energy, the electron is able to escape from its normal position associated with that atom, to become part of the current in an electrical circuit. By leaving this position, the electron leaves a hole behind. While the electron is negatively charged, the hole is recognized as a positive charge carrier and contributes to current. The PV cell has a built-in electric field, providing the voltage needed to drive the current through an external load, such as a light bulb.Photovoltaic cells are connected to form a module (or panel) typically 60 to 72 cells per module. Crystalline silicon cells produce approximately 0.5 V each irrespective of the size of the cell. Therefore a 72-cell module will operate at close to 36 V. Modules are then connected in series and parallel to form an array to generate the required current, voltage and power. The array is then connected to an inverter which converts the DC output into AC to match the requirement of the utility.The electricity produced by your PV system is completely independent of your electricity usage in the building as it is connected directly to the utility grid. It will rarely be the case that your electricity production exactly matches your demand. The grid essentially acts like a battery whenever you use less energy, feeding the excess electricity into the utility. On the other hand, if you need more electricity than your PV system produces, you are backed up by your local power utility provider.Table 1: Solar Photovoltaic components and explanations.System size & design, the Solar E way
Every household is different, so an initial upfront consultation with our clients is recommended. This is to determine a number of important factors, before tailoring a system to suit your needs.These are:
- A system that fits your budget (sizes can vary from 1.5KW up to and over 5KW)
- Available roof space and alternative locations such as on the ground or mounted
- Estimated energy required
Savings from Solar PV systems are varied depending on:
- Size of the system
- Consumption pattern
- Power supplier rates
- Feed in tariffs if applicable
- Various manufacturer panel technology
- Solar E is a locally owned and run business in Perth, WA
- We offer finance options to suit your financial circumstances
- Our in-house installation team is fully qualified and led by licensed electricians with specific experience in solar installation
- Solar E is a licensed REC trader – we can use the Government Rebate scheme to directly discount off your quote
- Solar E will undertake an initial assessment of your home; if we think your home is not suitable, we won’t sell a solar power system to you
- Clean Energy Council accredited
Solar E selects some of the best components in the market which make up your system.Including:
- System components that have passed Australian Standard Certification.
- Installation supervised and carried out by our fully qualified CEC (Clean Energy Council) accredited licensed installers.
- Electrical connectors can be either IP 65 or IP 67.
- 90% power output over 10 years.
- 80% power output over 25 years.
- Each panel has 3mm Tempered glass, EVA resin, weatherproof film and anodized aluminium frame for extended outdoor use in harsh environments
- Industry Standard Solar panels having a minimum 25 year limited performance guarantee on power output.
- Solar panels with a minimum 10 year warranty for defects/
- Certified CEC fire rating approval
The performance guarantee for the PV power output is given for 25 years. Over that period of time, the efficiency decreases to approximately 80% of its initial value at Standard Testing Condition. Owners are encouraged to check the performance to ensure the systems are operating at its optimal capability. This can be done by recording the energy on the inverter display board or through a wireless monitoring system.
The tilt angle is the angle of the PV panel from the horizontal ground. The tilt angle may be smaller or larger depending on the season (winter or summer). However, a minimum of 10° is recommended for standard installation to cater for self-cleaning preventing dirt from accumulating on the surface of the panel. Majority of domestic installations have their tilt angle aligned with the roof inclination. Brackets can be used to adjust the tilt angle of the panels.
The most ideal orientation for PV panels should be the true north (0°), however the angle is ultimately determined by the orientation of the roof where they are installed. Any orientation between -30° and 30° from the true north are acceptable angle for the PV panels with system performance between 95% and 100% energy yield.
Shading on any part of an array will reduce its energy output so if there is shading on a cell or module and it is connected to other cells or modules, their performance may also be reduced. In addition to that, partial shading can cause damage to PV cells. This is because the panels are connected in a series and as such, the weakest link determines the energy output. Solar PV panels have built-in bypass diodes to reduce the effect of partial shading.
Partial shading cannot be entirely eliminated, especially at times of sunrise or sunset when the shadows are longer. Marginal shading is generally accepted for time in the early morning and late evening due to the lesser energy production of the system. In the event where shading of panels cannot be eliminated, Solar E may suggest not installing a Solar PV system.
Soiling/Dirt of the Panels
Dirt deposited on the panels will form as a layer of shading on the panels. Since the dirt is deposited evenly across each panel, light still gets through but the Solar PV system will have a slightly reduced output. Natural rainfall is often sufficient to prevent the panel from accumulating large amounts of dirt; however cleaning of panels is required in very dusty and dry regions. On large applications it is available to carry out a yearly maintenance program to remove dirt and impurities that have accumulated over the course of a year.
PV cells are sensitive to temperature increases, the higher the cell temperature the lower the energy production. For example; when the solar radiation is at its strongest in summer at noon, the cells can be heated up to around 70°C or more. Heat is dissipated via the back of the panels by natural convection but it is very important to ensure clear air flow around and underneath the panels. A rise of 10°C lowers the effective power output of the PV system by 3% to 5%.
The efficiency of the PV system will reduce slowly over time, typically by 0.5% per annum. This means that the systems efficiency will be reduced to 80% of its initial value at STC.
For more information about Solar energy systems contact us today, or visit our display showroom at Unit 1 - 93A, Leach Highway, Kewdale, WA 6105