Solar PV Explained

Rooftop solar

    1000 Solar Roofs – can we do it?

Imagine having 10% of our rooftops go solar!

Alice Springs has come a long way with solar power since Alice Solar City launched in March 2008. From a base of 2 pioneering installations prior to launch, Alice Springs now has around 500 rooftop systems generating electricity directly from the sun. This is a great start, but there are over 10,000 roofs in Alice Springs, and we’d love to see our town achieve 1000 solar roofs.

The price of solar power systems has dropped by over 50% in the last few years and now rooftop solar power systems are more affordable than ever before.

Read further to find all the information you need about:

For more information, you can also download our new Alice Solar City Solar PV fact sheet or give us contact us if you have any specific enquiries. 

What is solar PV?

 A solar photovoltaic (PV) power system is a technology that converts the energy from sunlight into electrical energy.  Residential PV systems can meet some or all of a household's power needs, depending on the size of system and the household's needs.

In a typical system, a set of photovoltaic modules, or 'solar panels', are installed on the roof of your home, and the energy generated by these panels is passed through an inverter which creates electricity to match that coming in from Power and Water Corporation. A residential PV system can meet some or all of a household's power, depending on the size of the system and the household's needs.

In a typical system, a set of photovoltaic modules, or 'solar panels', are installed on the roof of your home. When the sun hits the panels, electrical current is generated (as DC) and fed to the inverter, which produces electricity at 240 volt AC (the same as the electricity grid). This electricity then feeds into your local electricity network via the electricity meter. The meter records the amount of electricity produced, and this information is used by Power and Water to provide a credit on your power bill.  The amount of electricity produced by a system (measured in kilowatt hours (KWh) is directly related to the capacity of the system installed. The amount of available roof space can limit the size of the system installed. Other factors can also affect generation.

More electricity is generated when:

  • The panels directly face the sun;
  •  The weather is cool and sunny;
  •  The days are longer.

Less electricity is generated when:

  • The panels are shaded (by trees or nearby structures, for example);
  • The weather is cloudy or rainy;
  • The panels have an accumulation of dust or other debris.
  • Roof orientation and pitch are not optimal

 In remote areas PV power systems rely on batteries to store energy so it can be used later; in urban settings like Alice Springs, systems don't use batteries and are instead connected to the electricity grid. By installing a grid connected solar PV system and entering into agreements with Power and Water Corporation (PWC) households become, in effect, mini power stations selling all of the electricity generated to PWC (see Power and Water Corporation website for feed-in tariff rates).  PV systems should not be confused with solar hot water systems, which are sometimes also referred to as 'solar panels'. In a solar hot water system, panels on your roof use the sun's energy to heat a fluid which then heats your hot water.

Why install a solar PV system?

 There are many reasons to have a PV system installed.

  • You will be generating clean, renewable energy.
  • You will save on your power costs as the PV system will meet some - or all - of your power needs.
  • The electricity generated by your PV system can be sold to PWC (subject to entering into the necessary standard agreements with PWC).  Under current arrangements, all the electricity generated is sold to PWC at  the standard flat tariff rate (19.77 cents/kWh until 30.6.2012)
  • Because solar power is generated during the day when the community's power demands are typically at their highest, your investment will help delay the need for expensive upgrades to our energy infrastructure.
  • The value of your home may be increased as demand for sustainability features in homes increases.

Can I supply all of my electricity needs from a solar PV system?

The answer to this question will depend on how much electricity you use and what size solar PV system you are able to install.

As a general  rule of thumb, a 1kW solar power system (typically 5 or 6 panels), installed on a roof with the optimal orientation, pitch and minimal shading, could produce around 1,600kWh/year. The average Alice Springs household uses about 8,500 kWh/year.

Connection to the grid is also subject to approval by the electricity network operator. As the amount of solar PV on the network increases, particularly in residential areas where solar power doesn’t always match household consumption, it becomes harder (and more expensive) for utilities like Power and Water to balance the network to ensure reliable and safe electrical supply.

You should therefore ensure that your preferred installer receives approval from PWC for your proposed solar PV installation before you place an order.

When installing a solar PV system, it is vital to also look for opportunities to improve your energy efficiency. Using solar water heating and ensuring that your home's air-conditioning needs are low are key ways to reduce your electricity use, and are typically more cost effective than buying a larger solar power system.

The home energy survey provided by Alice Solar City will help identify large and small measures you can take to reduce your energy consumption and make the most of your PV installation.

 

 

Downloadable fact sheet

You can download our solar PV fact sheet here