Solar PV

A Solar Photovoltaic system is a relatively easy way to generate your own clean, green energy at the point of use. Through on-site generation there is a gross reduction in transmission losses whereas typically a major proportion of electricity transmitted from a centralised power utility is wasted because of the distance travelled. Solar PV systems have a long operational life of 30 years and very little maintenance is required to achieve peak performance. Sustainable Harvest view the adoption of solar PV systems into a businesses carbon strategy as a sound investment due to the prospect of feed-in-tariff incentive and increased state and federal mandatory renewable energy targets (MRET).

The definition of photovoltaic is the conversion of sunlight into electricity. A collection of modules combine to create a solar array, and the size of this array correlates to the amount of power the system will produce. The array produces DC power, which is converted to 240V AC power through the use of an inverter.

The size of your system will depend on the physical space available for the installation of the panels, what loads (or portion) you wish to supply and budget.

When the sun is shining the system will be producing energy and powering the electrical loads operating at that time. At night, when the solar modules are not producing electricity, the electricity is delivered from the grid. If you export enough energy during the day, it will balance or exceed the amount you draw from the grid at night.

The benefits of PV systems include:

• Reducing peak₁ demands, not only reducing expenses but alleviating the threat of blackouts
• Feed in tariffs₂ are likely to be applied, which strengthens the economic case and achieves a payback under 10 years
• Once the system has been purchased, electricity is generated from a 'free' resource - the sun
• Solar electricity is generated without emitting greenhouse gases
• Solar panels or modules are silent, without any moving parts
• Solar modules are generally unobtrusively mounted on an existing roof
• Solar modules can be integrated into the building in the form of windows, walls, roof tiles or shading structures.
• Solar power can supplement or provide all your electricity consumption
• Solar power can feed electricity into the grid.
• Additional solar modules can be added later as demand or budget grows
• A solar module should last for at least 20 - 30 years.

Building integrated photovoltaic (BIPV) utilises the modules as part of the building envelope or facade. This is an intelligent application of a system as panels are used for a dual purpose. In BIPV applications modules can be used as shade awnings, shelters a translucent skylight or an aesthetic facade.

[1] Peak Load refers to the period of day or night where electricity demand is at it highest or 'peak'. Large peak loads are typical during summer afternoons or winter evenings when business and residential dwellings are using artificial cooling or heating on cold winter nights.

[2] Feed in Tariff or Feed-in Law or Solar Premium is an incentive structure that boosts the adoption of renewable energy through government legislation. The regional or national electricity utilities are obligated to buy 'green' electricity (electricity generated from renewable sources such as solar photovoltaics, wind power, biomass, and geothermal) at above market rates. This difference in price covers the cost disadvantages of adopting renewable energy sources and the rate differs between the different forms off power generation.