Glossary of Terms

Battery Storage

Battery storage refers to the storing of excess electrical energy  for later use.  For example, a domestic solar electricity system might store excess energy generated during the day for use when no solar energy is available, at night or during overcast periods during the day.  Currently, lithium-ion based battery arrays are popular, and many older systems use lead-acid batteries, but this an area where technology is yet to mature in terms of cost, durability and efficiency.


Bioenergy or biofuel is renewable energy made available from materials derived from biological sources or biomass. Biomass is any organic material which has stored sunlight in the form of chemical energy. As a fuel it may include wood, wood waste, straw,manure, sugarcane, and many other byproducts from a variety of agricultural processes.


A power or electrical grid is an interconnected network for delivering electricity from suppliers to consumers. It consists of generating stations that produce electrical power, high-voltage transmission lines that carry power from distant sources to demand centers, and distribution lines that connect individual customers.

Heat Pump

A heat pump is a device that provides heat energy from a source of heat to a destination called a “heat sink”.
While air conditioners and freezers are familiar examples of heat pumps, the term “heat pump” is more general and applies to many HVAC (heating, ventilating, and air conditioning) devices used for space heating or space cooling. When a heat pump is used for heating, it employs the same basic refrigeration-type cycle used by an air conditioner or a refrigerator, but in the opposite direction – releasing heat into the conditioned space rather than the surrounding environment. In this use, heat pumps generally draw heat from the cooler external air or from the ground. In heating mode, heat pumps are three to four times more efficient in their use of electric power than simple electrical resistance heaters.  Heat pumps make very efficient domestic hot water storage systems.

Kilowatt (kW)

1 kWatt is 1000 Watt.  The Watt is the international unit of power, expressed as Joule/second, and is used to express the rate of energy conversion or transfer at a given moment.  When dealing with electricity consumption/production, larger units such as the Kilowatt or Megawatt are often used.

A surface area of one square meter on Earth receives typically about one kilowatt of sunlight from the sun, on a clear day at midday, close to the equator.

Kilowatt Hour (kWh)

If energy is being transmitted or used at a constant rate (power) over a period of time, the total energy in kilowatt-hours is the product of the power in kilowatts and the time in hours. The kilowatt-hour is commonly used as a billing unit for energy delivered to consumers by electric utilities.

The terms power and energy are frequently confused. Power is defined as work per unit time, measured in units joules per second or watts. To produce power over any period of time requires energy. Energy is the application of power for a period of time.

LED Lights

Light emitting diode lights are efficient lights that generate less heat than traditional lights.  Typically, LED lights use ⅙ of the energy of incandescent lights.


Microgeneration is the small-scale generation of heat and electric power by individuals, small businesses and communities to meet their own needs, as alternatives or supplements to traditional centralized grid-connected power.

Net Metering

Under net metering arrangements, the electricity you generate is used to supply your own energy requirements and any excess generation that is not used in the premises is exported to the grid. By reducing the need for grid electricity, customers can reduce their electricity bills as they avoid purchasing electricity from the network. Bill savings will increase as electricity prices increase.


Photovoltaics (PV) is the name of a method of converting solar energy into direct current electricity using semiconducting materials that exhibit the photovoltaic effect: the creation of voltage or electric current in a material upon exposure to light.

PV Installation

Photovoltaic Installation:  installation of solar panels in order to generate electricity.  PV installation must be performed by licensed installers.

Most of the PV systems in Australia are small-scale rooftop installations of less than 100kW; however there are a number of larger-scale PV power stations with a capacity of more than 100 kW.  The Clean Energy Regulator, the Australian Government agency tasked with the administration of the Renewable Energy Target maintains a map of the PV installations in Australia.

Raw Metering

See also net metering.  Under raw (or gross) metering arrangements, all generated electricity is exported to the the grid, and all consumed electricity is imported from the grid, and thus requires two meters.

Renewable Energy

Renewable energy is energy which can be obtained from natural resources that can be replenished, on a human time scale.
Renewable energy technologies include technologies that use—or enable the use of—one or more renewable energy sources. Types of renewable energy technologies include:
●    Bioenergy
●    Geothermal energy
●    Hydropower
●    Ocean energy
●    Solar energy
●    Wind energy

Solar Hot Water

Solar hot water systems convert solar energy almost directly into hot water for domestic or industrial use.  Because there is little energy loss in the process, solar hot water systems are extremely efficient sustainable energy systems.

Sustainable Energy

Energy that is generated by means of either renewable energy technologies, or by means of technologies designed to improve energy efficiency.

Sustainable Firewood

Sustainable firewood refers to: efficient domestic use of firewood; ecologically sensitive collection methods; and replacement of the tree resource base with new tree plantings on a human timescale.

Thermal Fabric

The thermal fabric of buildings refers to heat loss and retention characteristics of the walls, roofs and floors of a building. Key measures for improving thermal fabric include: insulating walls, roofs and floors; double glazing and shading windows; and draught proofing.

Thermal Performance

Thermal Performance is the measurement of the efficiency of a building’s thermal fabric, generally measured in a star rating of up to 10 stars, with 6 stars being the minimum for new dwellings.


Zero Net Energy Town

The purpose of the Zero Net Energy Town (Z-NET) movement is to support towns and villages throughout Australia to satisfy their own energy needs from renewable energy sources in a way which is competitive with its current system of energy (in terms of price, quality, reliability, security of supply and so on).
This is achieved firstly by reducing energy use and then importing or locally producing enough sustainable energy to meet or exceed the community’s demand.