Offshore Renewable Energy

The Joint Nature Conservation Committee (JNCC)
provides advice on nature conservation to government and
industry on renewable energy proposals in the offshore environment.
It is JNCC policy to support appropriately sited renewable energy
developments because of the environmental benefits they can deliver
through sustainable energy generation.
The UK is currently generating over 5.1GW of
offshore renewable energy (around 5% of UK electricity
requirements) with a further 4.5GW under construction. The
Government is anticipating this will be delivered by 2020, thereby
ensuring the UK achieves 15% of its energy needs from renewable
sources. The majority of proposed windfarm development is located
in offshore waters where JNCC has a role in providing environmental
advice.
JNCC is a member of the
Offshore Wind Programme Board, which brings together senior
representatives from industry, UK and Scottish government, The
Crown Estate and Statutory Nature Conservation Bodies. The UK
Government released an update to its
UK Renewable Energy Roadmap in 2012, which sets out the
potential for growth in offshore wind generation to 2020, with the
sector potentially producing up to 18GW if costs come down.
With the increase in offshore renewables likely to continue,
JNCC will have an ever increasing role in providing strategic
environmental advice on offshore renewables and their potential
interaction with marine life. JNCC co-ordinate with country
conservation agencies on nature conservation issues related to
marine renewables, such as the potential for disturbance of marine
mammals arising from piling noise, and potential collision and
displacement effects on seabirds.
Offshore Renewable Energy and marine birds
Offshore wind development has the potential to impact UK and
international seabird and marine bird populations in a number of
ways, if not managed appropriately. Birds are at risk of direct
mortality from collision with turbine blades as they forage or
transit through sites.

They are also potentially subject to displacement from their
normal foraging habitat through disturbance. This can occur during
the construction phase, but also after construction in some cases.
Birds have also been observed to actively avoid offshore wind farms
by flying around them (e.g. during migration). This is known as the
barrier effect.
The Statutory Nature Conservation Bodies have produced an
updated Joint Interim Displacement Advice note to provide
information on how to present assessment information on the extent
and potential consequences of seabird displacement from offshore
wind farm developments.
It updates the previous interim displacement advice note
(Natural England and JNCC., 2012. Joint Natural England and
JNCC Interim Advice Note – Presenting information to inform
assessment of the potential magnitude and consequences of
displacement of seabirds in relation of Offshore Wind Farm
Developments) to take account of potential areas of disparity
in approaches that have arisen in casework since the original note
was issued. It also follows on from a Displacement Workshop (6-7
May 2015), run by JNCC and the Marine Renewables Ornithology Group
(MROG) and funded by The Crown Estate, which sought to make
progress towards developing a more refined best practice approach
to assessing displacement impacts.
Offshore Renewable Energy and marine mammals
Offshore renewable energy installation has the potential to
injure and disturb marine mammals as a result of the high levels of
noise produced by pile-driving, i.e. hammering of the turbine
foundations on the seabed. For example, there is some field
evidence for short-term behavioural responses to the noise, such as
displacement of harbour porpoises, however the long term
consequences on individuals fitness and on population vital rates
are less certain.
The assessment of the potential impacts on marine mammal
populations from offshore industries has used, on occasions, some
form of population modelling framework to ascertain the likelihood
of a population level impact resulting from the disturbance. JNCC
commissioned the guide below as an accessible reference on
population models used to help practitioners dealing with such
assessments.
Guide to population models used in marine
mammal impact assessments – JNCC Report 607
JNCC also worked with Natural England in
commissioning a report on the use of the iPCoD modelling
framework to assess the aggregate/cumulative effects of the
construction of offshore wind farms on the harbour porpoises in the
North Sea.
JNCC piling guidelines

The installation of driven piles in the marine environment
without mitigation is likely to produce noise levels capable of
causing injury and disturbance to marine mammals. In association
with DEFRA and the country agencies, JNCC has produced guidance on
‘the protection of marine European Protected Species from
injury and disturbance’. The piling protocol forms part of
that more general guidance and the recommendations should be
considered as ‘best practice’ for piling operations.