Photo courtesy of The Bunyip, Gawler, SA
Visiting 'Wwoofer' Harry Wykman with
Annemarie Brookman in front of the extension
In addition to the photovoltaic panels on the
roof of the extension you can see the solar
hot water panels on the roof of the old house
.
The system for the production of green electric power at The Food Forest comprises 30 thin-film amorphous silicon photovoltaic panels arrayed on the roof of the extension to the homestead.
Each panel nominally produces 58 Watts in ideal conditions.
The total output is expected to be about 1700 Watts (1.7 kilowatts) in full summer sun.
Amorphous panels maintain their output better than the mono or poly-crystalline ones when temperatures become extreme and operate better in low light situations, but the huge advantage is their low environmental cost. In fact the energy used to manufacture these panels is recouped within 2 years.
In this installation the panels are also used to shade the northern roof face, which they virtually cover, reducing the need for super-insulation in the roof.
The orientation of the roof is due north and roof pitch is approx 25 degrees in order to maximise the effectiveness of the modules.
Power produced will reduce the CO2 greenhouse emissions from conventional power production by 3 tonnes per year.
Inverter
The SMA 1700E Grid Connect Inverter will convert
up to 2200 Watts of direct current power from the photovoltaic system (which
varies but is often approx 190 volts) into alternating current at a steady
240 volts of perfect sinewave power.
It is connected to the Mains grid via a meter
which is capable of monitoring how much power is being exported from the
photovoltaic system to the grid and, when the energy use of the house is
greater than that being produced by the PV system, how much power is used
from the grid.
A display panel on the inverter oscillates from
readings of the power and voltage that the system is producing right now,
to what the system has produced today and then to what the system has produced
in its lifetime.
The inverter can be be linked to a computer for
continuous logging and data interpretation.
Installation
The system was designed and supplied by Sandy
Pulsford of Adelaide-based firm Solaris
Technology, one of Australia's longest established photovoltaic and
wind-power specialists.
Using the energy produced
See The
Energy Efficient Home page for details of how we make use of the system