14.40 Assessing Air Quality and Climate Change Impacts for Offshore Wind Farm Projects.pdf

1. Assessing Air Quality and Climate Change
Impacts for Offshore Wind Farm Projects
Routes to Clean Air 2023
Joe Parsons & Dr Saba Manzoor
10 October 2023

2. Air Quality and Carbon Emissions - Offshore Wind Farms | 10 October 2023
Offshore Wind Farm Project Overview
Figure 1: Project Hornsea Four
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Project: Hornsea 4
Developer: Ørsted
Location: Proposed ~ 69 km off the Yorkshire
Coast, in the Southern North Sea
Size: Investigating an offshore area of ~ 492 km².
Infrastructure Components:
• Offshore generating station (wind farm).
• Export cables leading to landfall.
• Onshore substation equipped with energy
balancing infrastructure.
• Connection to the electricity transmission
network.

3. Air Quality and Carbon Emissions - Offshore Wind Farms | 10 October 2023
Scope of Air Quality Assessment
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Construction
Potential Impact Construction Operation
Offshore Air
Quality
Offshore Air Quality impacts were scoped out,
deeming them unlikely to be significant.
Onshore Air
Quality
Impacts on human and ecological receptors as a
result of dust and particulate matter emissions.
Impacts on human and ecological receptors as a
result of plant and machinery emissions.
Impacts on human and ecological receptors as a
result of road traffic emissions

4. Air Quality and Carbon Emissions - Offshore Wind Farms | 10 October 2023
Existing Baseline
Figure 1: Project Hornsea Four
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AQMA status: HCC has an AQMA for
NO2 along A63, including study area;
ERYC has none.
AQ Monitoring: NO2 levels (40μg.m-3)
< limits except for two HCC sites
related to A63 emissions.
Background Pollutants: Air pollutant
concentrations < 75% of established
standards.

5. Air Quality and Carbon Emissions - Offshore Wind Farms | 10 October 2023
Assessment Methodology
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Construction Dust and Road Traffic
•Dust emissions' magnitude was
evaluated using criteria from the IAQM
guidance.
• NRMM emissions were evaluated
following the guidelines outlined in Defra
Technical Guidance Note 22.
•For assessing the impact of road traffic
and plant exhaust emissions on human
receptors, guidelines from IAQM & EPUK,
2017 were utilised.
•The assessment of road traffic impacts
on designated ecological sites was
guided by Natural England 2008.
Figure 2. Air Quality Modelling Assessment schematic
(Reference: adapted from http://www.cerc.co.uk/environmental-software/ADMS-Roads-model.html)

6. Air Quality and Carbon Emissions - Offshore Wind Farms | 10 October 2023
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Onshore Air Quality Study Area – Construction Dust
Figure 3: Air Quality
Study Area –
Construction Dust
(a)
(b)
(c)
(d)
River Hull
Headwaters SSSI
River Hull
Headwaters SSSI
Bryan Mills Field
SSSI
Birkhill Wood
Ancient Woodland
 Human receptors
within 350m of the
Onshore Development
Area (ODA) and within
50m of routes used by
construction vehicles
(IAQM 2016); &
 Ecological receptors
within 200m of the
ODA (Natural England)
and within 50m of
routes used by
construction vehicles
(IAQM 2016).

7. Air Quality and Carbon Emissions - Offshore Wind Farms | 10 October 2023
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Onshore Air Quality Study Area – Construction Plant + Traffic
Construction Road
Traffic emissions
 Human receptors within
200m of all roads that
trigger the traffic
screening criteria and
adjoining roads within
200 m (EPUK & IAQM
2017) Figure 4a: Air Quality Study Area -Road Traffic and Human Receptors
Construction phase Non-
Road Mobile Machinery
emissions
 Human and ecological
receptors within 200m
of the ODA where
NRMM will be located.

8. Air Quality and Carbon Emissions - Offshore Wind Farms | 10 October 2023
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Onshore Air Quality Study Area – Road Traffic
 Ecological receptors within
200m of all roads that
trigger the traffic screening
criteria and adjoining roads
within 200 m (EPUK &
IAQM 2017)
Figure 4b: Air Quality Study Area - Road Traffic and Ecological Receptors

9. Air Quality and Carbon Emissions - Offshore Wind Farms | 10 October 2023
Outcomes
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 Hornsea Four onshore development assessed
for air quality effects.
 Construction dust and fine particulate matter
impacts mitigated with site-specific measures.
 NRMM emissions controlled with embedded
measures, no significant impact.
 Project-generated road traffic emissions are
predicted to be not significant on existing
human receptors, with no significant impact on
designated ecological sites.
 No significant inter-related air quality impacts
found in the assessment.

10. Air Quality and Carbon Emissions - Offshore Wind Farms | 10 October 2023
Carbon Assessment
 Purpose of offshore wind farms
is to mitigate climate change and
reduce emissions.
 Challenges from some
stakeholders as to whether
emissions associated with
offshore wind farms have been
accounted for.
 Construction phase – capital and
carbon heavy.
 Embodied emissions in materials
and vessel movements.
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11. Air Quality and Carbon Emissions - Offshore Wind Farms | 10 October 2023
Assessment Approach
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12. Air Quality and Carbon Emissions - Offshore Wind Farms | 10 October 2023
Outcomes
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 GHG emissions associated with project greater than 7
million tonnes
 Largest proportion in O&M phase, associated with
maintenance vessels (likely to be overestimation)
 3.5 million tonnes during ‘capital’ or construction phase
 Carbon intensity of electricity produced – 15.6 kg CO2e
per kWh (380 g CO2e per kWh for natural gas).
 Avoidance of emissions from fossil fuel generated
sources:
 Carbon payback, 1.5 years.
 Emission savings 3 million compared to UK grid
average, or 180 million tonnes CO2e if assume to
be replacing natural gas.

13. Air Quality and Carbon Emissions - Offshore Wind Farms | 10 October 2023
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Thank you