Draft National Wind Farm Development Guidelines - July 2010

What are the limitations of this technique
It is currently very difficult to create a high-fidelity virtual reality experience, due largely to
technical limitations on processing power, image resolution and communication
bandwidth. Producing a VR Model can be overly time consuming and expensive.
However, those limitations are expected to eventually be overcome as processor, imaging
and data communication technologies become more powerful and cost-effective over
time.
C.7.8 Cumulative impact mapping
What is Cumulative Impact Mapping
Cumulative effects are those which occur, or may occur, as a result of more than one
large scale infrastructure project located within a particular area or region.
The degree of cumulative impact is a product of the number of and distance between
individual wind farms, the inter-relationship between their associated viewshed (or ZVI), the
overall character of the landscape and its sensitivity to wind farms, and the siting and
design of the wind farms themselves.
What is Cumulative Impact Mapping used for
Cumulative impact mapping is used to illustrate (in 2-Dimensional form) the summation of
possible visual overlap that may occur as a result of the proposed wind farm development
in combination with other developments (associated with or separate to it), or with actions
that occurred in the past, present or are likely to occur in the foreseeable future.
Mapping possible cumulative impact is usually undertaken at an early stage of a
landscape and visual assessment to determine where problem areas may occur (i.e.
where large scale infrastructures have the potential to become the dominant or defining
visual characteristic of the landscape), consequently resulting in a loss of landscape
character and diversity.
How do I go about it
Illustrating the base cumulative impact
Identify, record and map other wind farms, major infrastructure and/or large scale
developments (including projects that have been approved but not yet built, or that are
being developed in parallel with the wind farm) in the study area or wider region, as
identified in the Preliminary landscape and visual assessment (Identification of possible
cumulative impacts, page 80). A table such as the one below should be used to record
multiple wind farm developments (if applicable).
Using circle distance cones of 3km, 6km and 12km radii, illustrate the potential visual
impact of each of the identified infrastructures/ developments.
• 12 km = Low visual impact
Depending on surrounding context, alternative distance cones can be mapped. The table
below can be used to help determine the appropriate measurements based on the likely
visual impact of a wind turbine.
Page 106 Draft National Wind Farm Development Guidelines – 2 July 2010