There are two main types of solar power systems, grid-connected and stand-alone.
GRID CONNECTED SYSTEMS
Grid Connected Power Systems interact with the electricity supply grid. The main components of the system are the renewable energy source (solar Panels) and a grid interactive inverter, which converts the DC voltage generated by the system to the normal 230V AC household supply.
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If the household uses more energy than the renewable sources can supply the shortfall is provided by the grid, therefore s ystem sizing is not critical
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If the system is supplying more energy than is needed, the excess is fed back into the grid
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The household only pays (or is paid) for the difference between what is imported and what is exported
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However, Grid Connected Systems do not normally have storage batteries. If the grid goes down the inverter will cut out for safety reasons and there will be no electricity available.
Positioning
Ideally you should have a large roof area facing true north. We can also install your system on a west facing roof, but this requires extra time and materials to tilt the panels to the north.
Energy Consumption
We highly recommend reducing your energy use as much as possible before installing solar panels. Energy efficiency has been proved many times to be the most economically and environmentally sensible strategy to follow before any other. Large gains can be made in energy efficiency primarily through simple behaviour change, such as turning off unused lights and appliances and adjusting heating and cooling. Reducing your energy use will also allow your solar power system to offset a larger percentage of your energy use.
Average energy use for a family home in Melbourne is around 15-20kWh per day. It is usually not hard to get this below 10kWh per day and most houses can be brought under 5kWh per day with some effort and investment.
You can find your daily average energy use on your electricity bill. If you are well above the average, please investigate reducing your energy use first. We can help you identify your wasted energy with an eco-audit, which also covers water and thermal efficiency.
The WestWyck Project - Grid Connected PV Solar Electricity
Solar Electricity and Hot Water for the WestWyck project was designed, supplied and fitted by the Environment Shop and its renewable energy accredited engineers and installers.
WestWyck occupies the building and grounds of the former Brunswick West Primary School. The WestWyck developers have brought the building to new and vibrant life as an urban demonstration eco-housing project of positive environmental value, driven by high design standards.
The environmentally sustainable features include apartments built to minimise energy usage through double-glazing, heavy insulation, careful selection of lights and appliances and cross-flow ventilation systems. The apartments have been built making maximum use of re-used and recycled materials to the principles of healthy building, minimising off-gassing and toxic materials.
Solar Electric and Evacuated Tube Solar Hot Water Installation at WestWyck.
The project includes water conservation, achieved through selection of efficient appliances, maximising roof water harvesting and re-applying this through the solar hot water system, treating and re-using greywater from bathrooms and laundries and treating the blackwater and human biodegradable wastes on site.
Energy/Greenhouse Savings:
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Total Solar Output (Saving): 4,950 Peak Watts
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Electricity Per Day: 28 kWh per day in summer
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Electricity Per Annum: 8.23 Mega Watt Hours
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Greenhouse Gas Yearly: 11.9 tonnes CO²
Solar Electricty System
5 Apartment Buildings
Solar Panels: 30 x BP Solar 165 Watt, 24 Volt, Polycrystalline Silicon Photovoltaic Solar Panels
Panel Area: 7.6m² per unit (37.8m² total)
Inverters: SMA, Sunnyboy 1100E Grid Connect Inverters
Wiring: DC wiring system to connect the PVs to Inverter, AC wiring system to connect Inverter to switchboard, Isolator Switches and circuit breakers.
Framing: Custom made aluminium frame system engineered for PV systems
Roof penetration and Isolation switch on Solar Array
Integration of Solar System into existing Switchboard
Stand Alone Power Systems (SAPS)
Sometimes known as Remote Area Power Supplies (RAPS), these systems are becoming more common in less remote areas. They are more complex and expensive than Grid Connected Systems because they need to be self-sufficient.
The main components of a Stand-Alone System include:
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A renewable Energy Source such as Wind Generators, Solar Panels or Hydro Turbines.
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Control Equipment for battery charging and back-up power source operation.
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Storage Batteries.
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An Inverter. This is not required if the home runs 12 or 24V DC appliances. Although DC appliances are usually more energy efficient than their AC counterparts, they are more expensive and the range is limited. DC systems also need larger capacity and more expensive wiring. Some SAPS systems use a combination of AC and DC appliances.
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A Generator set for emergency back-up. These are generally installed in PV wind systems, but not micro-hydro. They are used for: * Charging the batteries. * Supplying specific high power loads. * Emergency back-up in periods of unfavourable weather or when loads are larger than the original design.
It is generally recommended that the system includes a generator for battery charge equalisation.
Your SAPS system should be designed to meet the required household load. Excess energy generated is stored in batteries for use then the renewable source is not available. The battery bank should be sufficient to provide power for several days.
SAPS systems are usually installed where electricity supply is not available or connection costs are high. However, some people install SAPS to be independent from the mains supply or to have reliable power in areas where blackouts are common.
In some cases it may be appropriate to use more than one type of renewable energy source, such as a photovoltaic system with a wind system.
Rebate Systems
Under the Photovoltaic Rebate Program (PVRP), and the Renewable Remote Power Generation Program (RRPGP), cash rebates are now available from the Australian Greenhouse Office (AGO) to householders who install grid-connected or stand-alone photovoltaic systems. The rebate covers about one third to half of the price of the system excluding fossil fuel back-up generators. For more information call 1300 138 122 or see the AGOs website at www.greenhouse.gov.au . Some state governments provide additional rebates.
Remote Solar Power Information Sheet 
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