Draft National Wind Farm Development Guidelines - July 2010

F
Electromagnetic Interference
F.1 Introduction
Wind turbines can produce electromagnetic interference (EMI), in two ways. Firstly in the
form of an electric and magnetic (electromagnetic) field that may interfere with
radiocommunications services, and secondly, due to the obstruction of
radiocommunications services by the physical structure of the wind turbines.
Under the Australian Radiocommunications Act 1992, “interference” is defined as:
• In relation to radiocommunications: Interference to, or with, radiocommunications
that is attributable, whether wholly or partly and whether directly or indirectly, to an
emission of electromagnetic energy by a device; or
• In relation to the uses or functions of devices: Interference to, or with, those uses or
functions that is attributable, whether wholly or partly and whether directly or
indirectly, to an emission of electromagnetic energy by a device.
In using this definition, the Radiocommunications Act deals with the radiocommunications
interference caused by electromagnetic fields and provides protection for users where
such interference is caused. It does not, however, deal with radiocommunications
interference caused by physical obstructions. These guidelines will assist proponents by
establishing best practice for managing the EMI that may be caused by the physical
structure of the wind farm turbines, as well as that which may be caused by
electromagnetic fields.
The intention of the guidelines, in relation to EMI, is to minimise the potential for EMI from
wind farms by providing best practice advice on how wind farm proponents should:
• Identify all the parties potentially affected by EMI due to the construction of the wind
farm.
• Assess all potential EMI impacts.
• Consult with the parties.
• Mitigate against any potential EMI effects.
This should enable the developer to site and design a wind farm development to avoid
adverse impacts to licensed radiocommunications services.
F.2 Background
F.2.1
Types of EMI considered
EMI may affect various radiocommunications systems, including broadcast radio and
television, mobile phones and radar.
As with the sites often selected for wind farm developments, telecommunications
infrastructure is also often located on high points in the landscape to maximise their
performance. This is because broadcast radiocommunications service providers seek to
reach as many customers’ receivers as possible, with signals above a certain threshold
level, in order to provide an acceptable service level in terms of performance and
reliability. Radar services also seek a broad coverage area in order to detect their target,
and point-to-point radiocommunications services require an unobstructed line-of-sight
path between a single transmitter and receiver pair in order to operate effectively.
Any obstructions between a transmitter and receiver will cause degradation to a
radiocommunications signal. Obstructions in the vicinity of a radiocommunications service
may also cause reflections or refraction which can degrade a radiocommunications
signal, and signals from a transmitter located on a high point in the landscape are less
Draft National Wind Farm Development Guidelines – 2 July 2010 Page 165