Locking Parklands, Weston-super-Mare Keepmoat Homes - Energy and Sustainability Statement AES Sustainability Consultants Ltd February 2021
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Locking Parklands, Weston-super-Mare Keepmoat Homes Energy and Sustainability Statement AES Sustainability Consultants Ltd February 2021
Author Date E- mail address
Produced By: Alice Gent 05.02.2021 Alice.Gent@aessc,co,uk
Reviewed By: Andrew McManus 05.02.2021 Andrew.McManus@aessc.co.uk
Revision Author Date Comment
Rev0 Alice Gent 05.02.2021 Initial Issue
Rev1 Alice Gent 09.02.2021 -
This statement has been commissioned by Keepmoat Homes to detail the proposed approach to
energy and CO2 reduction to be employed in development of Locking Parklands, Weston-super-
Mare. It should be noted that the details presented, including the proposed specifications, are subject
to change as the detailed design of the dwellings progresses, whilst ensuring that the overall
commitments will be achieved.
2
Energy and Sustainability Statement
Locking Parklands, Weston-super-Mare
February 2021Contents List of figures & tables
Figure 1. Proposed Site Layout ............................................................................................................................................ 4
Introduction .................................................................................................................................................................... 4
Table 1: Site-wide Part L compliant energy demand and CO2 emissions .......................................................... 8
Planning Policy .............................................................................................................................................................. 5
Table 2. Part L compliant energy demand & CO2 emissions ................................................................................... 8
Baseline Energy Demand and CO2 Emissions .................................................................................................. 8
Figure 2. The Energy Hierarchy ........................................................................................................................................... 9
Energy & CO2 Reduction Strategy ........................................................................................................................ 9
Table 3. Benefits of the Fabric First approach............................................................................................................ 10
As Designed Performance ....................................................................................................................................... 12
Table 4. Indicative construction specification – main elements .......................................................................... 10
Low Carbon and Renewable Energy Systems ................................................................................................ 13
Table 5. Site-wide energy demand and CO2 emissions after fabric efficiency measures .........................12
Overall Energy and CO2 Reduction Achieved ................................................................................................ 17
Table 6. Energy demand of sample dwellings after fabric efficiency and low carbon heat ....................12
Conclusions .................................................................................................................................................................... 18
Table 7. Individual Biomass Heating feasibility appraisal ....................................................................................... 14
Table 8. Solar Thermal systems feasibility appraisal ................................................................................................ 14
Table 9. Solar photovoltaic systems feasibility appraisal .......................................................................................15
Table 10. Ground Source Heat Pump systems feasibility appraisal ....................................................................15
Table 11. Total site-wide energy demand and CO2 emissions ................................................................................17
3
Energy and Sustainability Statement
Locking Parklands, Weston-super-Mare
February 2021Introduction
The statement demonstrates that the development will incorporate significant fabric
Preface improvements, low carbon technology and renewable energy provision. The scheme will be
a no gas development, will meet a 31% reduction in CO2 from Part L of the Building
This Energy and Sustainability Statement has been prepared on behalf of Keepmoat Homes Regulations 2013, with steps towards the Future Homes Standard and with an aspiration to
South West in support of the application for development of Locking Parklands, Weston- deliver 15% of the site to zero carbon.
super-Mare.
Development Description
The development site is located on the eastern edge of Weston-super-Mare, 5km east of the
town centre.
The proposals addressed within this statement would deliver 425 dwellings across a mix of
two to four bedroom houses and one and two bedroom apartments, together with circa
300m2 of non-residential floorspace. The proposed site layout is shown in Figure 1.
Purpose and Scope of the Statement
Outline planning permission for the wider scheme was granted under application reference
16/P/2758/RG4 in January 2018 for the erection of 700 dwellings (15.07ha of residential
land); 14,500 sq.m of office floorspace (1.73ha of employment land B1 Use); retail unit; 420
place 2-form primary school and associated playing fields; landscaping, allotments, open
space and necessary infrastructure works and demolition of existing farm buildings within
Locking Head Farm (Agricultural Buildings to the east of Locking Head Cottages -NOT
including Listed Buildings at Locking Head Farm).
This statement has been prepared to demonstrate how Phase 1 of the development will
address Condition 30 of the 16/P/2758/RG4 outline planning approval, as well as relevant
national and local policies relating to sustainable development, including North Somerset
Council Core Strategy Policy CS2 and North Somerset Replacement Local Plan 2007 Policy
Figure 1 . Proposed Site
Sit e Layout
GDP/3.
It will demonstrate that guidance contained within the North Somerset District Council’s
‘Creating Sustainable Buildings and Places’ Supplementary Planning Document (SPD) has
been followed when developing the strategy and that a full assessment of renewable and
low carbon technologies has been undertaken to assess feasibility for installation at the
development.
4
Energy and Sustainability Statement
Locking Parklands, Weston-super-Mare
February 2021Planning Policy
Planning Conditions Local Planning Policy
Local policy relating to the sustainable design and construction of buildings is contained
Outline permission for the wider development was granted under application reference
within the North Somerset Replacement Local Plan, adopted in March 2007 (now
16/P/2758/RG4. This energy statement primarily will address Condition 30, extracted below;
superseded by the Sites and Policies Plan Part 1 Development Management Policies), and the
North Somerset Core Strategy, adopted in April 2012 and revised in March 2013. The
Notice of Decision – Condition 30 following extracts from these documents are relevant to the energy strategy:
The dwellings hereby approved shall not be occupied until measures to generate 15%
of the on-going energy requirements of the use through micro renewable or low North Somerset Core Strategy 2012
carbon technologies have been installed and are fully operational in accordance with
CS2: Delivering sustainable design and construction
the approved details that have been first submitted to and approved in writing by the
Local Planning Authority. Thereafter, the approved technologies shall be permanently New development both residential (including conversions) and non-residential should
retained.
demonstrate a commitment to sustainable design and construction, increasing energy
Reason: In order to secure a high level of energy saving by reducing carbon emissions
efficiency through design, and prioritising the use of sustainable low or zero carbon
generated by the use of the building in accordance with policy CS1 and CS2 of the forms of renewable energy generation in order to increase the sustainability of the
North Somerset Core Strategy. building stock across North Somerset.
When considering proposals for development the council will:
1) require designs that are energy efficient and designed to reduce their energy
demands;
2) require the use of on-site renewable energy sources or by linking
with/contributing to available local off-site renewable energy sources to meet a
minimum of 10% of predicted energy use for residential development proposals
involving one to nine dwellings, and 15% for 10 or more dwellings; and 10% for non-
residential developments over 500m² and 15% for 1000m² and above;
3) require as a minimum Code for Sustainable Homes Level 3 for all new dwellings
from October 2010, Level 4 from 2013, rising to Level 6 by 2016.
5
Energy and Sustainability Statement
Locking Parklands, Weston-super-Mare
February 2021North Somerset Replacement Local Plan 2007 National Policy
Policy GDP/3 – Promoting good design and sustainable construction
co nstruction Government policy in relation to the energy performance of buildings has been evolving over
the past decade, following government commitments to reduce the emission of greenhouse
In determining proposals, where appropriate and relevant, account will be taken of: gases – particularly CO2. This obligation was enshrined in the Climate Change Act 2008,
which commits the UK to achieving a mandatory 80% reduction in the UK’s CO2 emissions
xi. whether the proposal makes a positive contribution to a high level of energy by 2050, compared with 1990 levels.
saving, over and above that required by building regulations, through siting,
orientation, built form, renewable energy technologies, design and materials; In 2016, the UK government ratified the Paris Agreement, which provides a framework for
governments to pursue the target of limiting global warming below 2°C.
Paragraph 4.45
The built environment has a key role to play in delivering on these international
Policy GDP/3 seeks a high level of energy saving. A written appraisal of how
commitments, as it accounts for approximately a third of overall CO2 emissions. These
sustainable construction principles will be incorporated into the development will
commitments have been translated into national policies within the built environment driven
therefore be required. The Council expects that … all new dwellings, will generate a
by, amongst other mechanisms, the EU Energy Performance of Buildings Directive and the
minimum of 15% of predicted energy requirements through on-site renewable energy
generation systems. 2012 Energy Efficiency Directive.
Following the introduction of the 2013 edition of Building Regulations Part L, the successive
updates now require regulated CO2 emissions levels from new build domestic buildings to
be approximately 30% lower than 2006 levels.
The Government proposes that the Building Regulations are the appropriate mechanism to
drive future standards with respect to energy consumption, with local authorities able to
apply the optional requirements of the national technical standards with respect to water
consumption and space.
National Planning Policy Framework
In February 2019, the Government published the updated National Planning Policy
Framework (NPPF), which sets out the Government’s planning policies for England and how
these are expected to be applied.
The planning process has been identified as a system to support the transition to a low
carbon future in response to climate change by assisting in the reduction of greenhouse gas
emissions and supporting renewable and low carbon energy.
6
Energy and Sustainability Statement
Locking Parklands, Weston-super-Mare
February 2021Paragraph 150 sets out what is expected from new developments when considering The Government has confirmed that the higher of the two options for carbon emissions
strategies to mitigate and adapt to climate change: presented - a ~31% CO2 reduction – will be adopted. These standards, to be referred to as
‘Part L 2021’ will come into effect from June 2022.
150. New development should be planned for in ways that:
Proposed Strategy
Avoid increased vulnerability to the range of impacts arising from climate change.
It is proposed that the development is designed to consider the future energy efficiency
When new development is brought forward in areas which are vulnerable, care should
standards of the Building Regulations in addition to incorporating all applicable guidance
be taken to ensure that risks can be managed through suitable adaption measures,
contained within Condition 30 and Policies CS2 and GDP/3 relating to renewable energy
including through the planning of green infrastructure; and
provision and the construction of highly efficient buildings which seek to minimise energy
demand and CO2 emissions.
Can help to reduce greenhouse gas emissions, such as through its location, orientation
and design. Any local requirements for the sustainability of buildings should reflect the
On the basis of the imminent improvement to national standards, a commitment has been
Government’s policy for national technical standards.
made for this site to increase dwelling performance above Part L1a 2013 to achieve the
additional 31% reduction in CO2 emissions in advance of the national regulatory timetable.
The strategy will follow the energy hierarchy approach, with improved fabric, low carbon
Current National Policy Standards
heating systems and photovoltaics.
The NPPF requires that “local planning authorities should …when setting any local
requirement for a building’s sustainability, do so in a way consistent with the Government’s The proposed dwellings will therefore be constructed following a fabric first approach to
zero carbon buildings policy and adopt nationally described standards.”1 significantly exceed the current Building Regulations requirements, incorporating high
standards of thermal insulation, airtightness and thermal bridging, together with efficient
A policy announcement presented by HM Treasury as part of the July 2015 productivity plan heating and lighting systems. In addition, where possible the dwellings will be designed in
“Fixing the Foundations”2 advised that the Government considered that energy efficiency accordance with the principles of passive design, with glazing and orientation considered to
standards introduced through recent changes to Building Regulations ‘need time to become take advantage of solar gain without building in potential overheating risk in a changing
established’ and will therefore persist until further notice. future climate.
This statement therefore sets out details relating to building energy performance standards The scheme will be a no gas development, targeted to meet a minimum of 31% reduction in
and proposes an approach through which these will be achieved in a manner which improves CO2 compared with Part L of the Building Regulations 2013 and with an aspiration to deliver
the long-term sustainability of the dwellings. 15% of the site to zero carbon.
Changes to Part L1A
A consultation was launched by BEIS in October 2019, setting out plans for the ‘Future
Homes Standard’, including proposed options to increase the energy efficiency requirements
for new homes. The Future Homes Standard will require new build homes to be future-
proofed with low carbon heating and world-leading levels of energy efficiency; it will be
introduced by 2025 as announced in the Government’s Spring Statement.
1 Department for Communities and Local Government, 2012, NPPF, paragraph 95 2 HM Treasury, July 2015, ‘Fixing the Foundations’ Productivity Plan
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Energy and Sustainability Statement
Locking Parklands, Weston-super-Mare
February 2021Table 2. Part L compliant energy demand & CO2 emissions
Baseline Energy Demand and CO2 Emissions
Energy Demand CO2 emissions
House Type
The development is to be designed and constructed to meet the requirements of Part L1A (kWh/yr) (kgCO2/yr)
of the Building Regulations 2013, therefore compliance with this standard forms the first Ground Floor Apartment 6030 1813
stage in the sustainable construction approach.
Mid Floor Apartment 6202 1639
Part L compliance is assessed through the Standard Assessment Procedure (SAP), which Top Floor Apartment 6923 1994
uses the ‘Target Emission Rate’ (TER) – expressed in kilograms CO2 per metre squared of Brantwood Detached 7290 2518
total useful floor area, per annum – as the benchmark. The calculated performance of the
dwelling as designed - the Dwelling Emission Rate (DER) – is required to be lower than this Caddington Semi-Detached 5978 2081
benchmark level. Carlton End-Terrace 6022 2097
Dalton End-Terrace 6040 2102
The energy demand of the Part L compliant development is also calculated as part of this
process, and takes into account all regulated energy demand, in line with North Somerset Dartmouth Mid-Terrace 7300 2545
guidance on the requirements for Energy Statements. Embleton Detached 7332 2541
At this stage dwelling designs have not been undertaken, and therefore in order to develop Embleton Semi-Detached 7102 2465
the proposed strategy, indicative calculations have been undertaken to a range of dwelling Foxhill Detached 7326 2538
types covering a range of potential house types in order to build a representative site model
Foxhill Semi-Detached 7253 2514
to establish the renewable energy provision required to meet the planning policy.
Galby End-Terrace 6925 2412
Based on these calculations, the estimated site-wide Part L compliance CO2 emissions and Galby Mid-Terrace 6349 2220
energy demand are shown in Table 1:
Henbury Detached 7276 2527
Table 1: Site-
Site-wide Part L compliant energy
energy d emand and CO2 emissions Henbury Mid-Terrace 6209 2171
Henbury Semi-Detached 6781 2362
Part L Compliant Energy Demand Part L Compliant CO2 emissions
(kWh/yr) (kgCO2/yr) Lambeth Detached 7776 2700
Lambeth End-Terrace 7400 2574
2,916,259 976,316
Newton Detached 9041 3123
The estimated site-wide Part L compliance CO2 emissions and energy demand for a range of Preston Detached 8064 2797
the proposed dwelling types are reported in Table 2. Preston End-Terrace 7528 2617
Rye Semi-Detached 7628 2653
Westbrook Detached 8781 3047
8
Energy and Sustainability Statement
Locking Parklands, Weston-super-Mare
February 2021Be Clean – supply energy efficiently
Energy & CO2 Reduction Strategy
The design and specification of building services to utilise energy efficiently is the next stage
of the hierarchy, taking into account:
Overview
The proposed construction specification and sustainable design principles to be applied to • High efficiency heating and cooling systems
the development will ensure that each dwelling meets at 31% CO2 reductions from the Part • Ventilation systems (with heat recovery where applicable)
L1A baseline of the Building Regulations through fabric measures alone. • Low energy lighting
• High efficiency appliances and ancillary equipment
The proposals will follow the Energy Hierarchy approach to sustainable construction (fabric
first).
Be Green – use low carbon / renewable energy
Low carbon and renewable energy systems form the final stage of the energy hierarchy and
can be used to directly supply energy to buildings, or offset energy carbon emissions arising
from unavoidable demand. This may be in the form of:
• Low carbon fuel sources – e.g. biomass
• Heat pump technologies
• Building scale renewable energy systems
• Small-scale heat networks
• Development-scale heat networks
As this hierarchy demonstrates, designing out energy use is weighted more highly than the
generation of low-carbon or renewable energy to offset unnecessary demand. Applied to
the development, this approach is referred to as ‘fabric first’ and concentrates finance and
efforts on improving U-values, reducing thermal bridging, improving airtightness, and
installing energy efficient ventilation and heating services.
This approach has been widely supported by industry and government for some time,
Figure 2 . The
The Energy Hierarchy particularly in the residential sector, with the Zero Carbon Hub and the Energy Savings Trust
having both stressed the importance of prioritising energy demand as a key factor in
Be Lean – reduce energy demand delivering resilient, low energy buildings.
The design of a development - from the masterplan to individual building design - will assist The benefits to prospective homeowners of following the Fabric First approach are
in reducing energy demand in a variety of ways, with a focus on minimising heating, cooling summarised in Table 3.
and lighting loads. Key considerations include:
• Building orientation – maximise passive solar gain and daylight
• Building placement – control overshading and wind sheltering
• Landscaping – control daylight, glare and mitigate heat island effects
• Building design – minimise energy demand through fabric specification
9
Energy and Sustainability Statement
Locking Parklands, Weston-super-Mare
February 2021Table 3. Benefits of the Fabric First approach Improved fabric specification
Fabric Bolt-
Bolt- on In order to ensure that the energy demand of the development is reduced, the dwellings
energy renewable should be designed to minimise heat loss through the fabric wherever possible. Table 4
efficiency energy details an indicative fabric specification of the major building elements, with the first column
measures technologies in this table setting out the Part L1A limiting fabric parameters in order to demonstrate the
potential improvements.
Energy/CO2/fuel bill savings applied to all dwellings
Table 4. Indicative construction
construction specification – main elements
Savings built-in for life of dwelling
Part L1a Limiting Fabric
Highly cost-effective Indicative Specification
Parameters
Increases thermal comfort External wall – u-value 0.30 W/m2K 0.17 W/m2K
Potential to promote energy conservation Party wall – u-value 0.20 W/m2K 0.00 W/m2K
Plane roof – u-value 0.20 W/m2K 0.09 W/m2K
Minimal ongoing maintenance / replacement costs
Ground floor – u-value 0.25 W/m2K ≤ 0.12 W/m2K
Significant disruption to retrofit post occupation
Windows – u-value 2.00 W/m2K 1.20 W/m2K
Doors – u-value 2.00 W/m2K 1.10 W/m2K
Building Regulations standards – Fabric Energy Efficiency
Air Permeability 10 m3/h.m2 at 50 Pa 5.00 m3/h.m2 at 50 Pa
In addition to the CO2 reduction targets, the importance of energy demand reduction was
further supported by the introduction of a minimum fabric standard into Part L1A 2013, based Thermal Bridging Y = 0.150 (default) Y = ≤ 0.040 (calculated)
on energy use for heating and cooling a dwelling. This is referred to as the ‘Target Fabric
Energy Efficiency’ (TFEE), and expressed in kWh/m2/year.
This standard enables the decoupling of energy use from CO2 emissions and serves as an Thermal bridging
acknowledgement of the importance of reducing demand, rather than simply offsetting CO2
The significance of thermal bridging as a potentially major source of fabric heat losses is
emissions through low carbon or renewable energy technologies.
increasingly understood. Improving the U-values for the main building fabric without
accurately addressing the thermal bridging will not achieve the desired energy and CO2
The TFEE is calculated based on the specific dwelling being assessed with reference values
reduction targets.
for the fabric elements contained within Approved Document L1A. These reference values
are described as ‘statutory guidance’ as opposed to mandatory requirements, allowing full
The specification should seek to minimise unnecessary bridging of the insulation layers, with
flexibility in design approach and balances between different aspects of dwelling energy
avoidable heat loss therefore being reduced wherever possible. Accurate calculation of these
performance to be struck so that the ultimate goal of achieving the TFEE is met. The
heat losses forms an integral part of the SAP calculations undertaken to establish energy
proposed approach and indicative construction specifications are set out in the following
demand of the dwellings, and as such thermal modelling will be undertaken to assess the
sections of this Strategy.
performance of all main building junctions. It is calculated that the average total Y value is
around 0.040, against a SAP default figure of 0.150.
10
Energy and Sustainability Statement
Locking Parklands, Weston-super-Mare
February 2021Air leakage Adopting energy efficient heat pump technology exceeds the proposed strategy of
achieving a 31% CO2 reduction over Part L1a Building Regulations 2013.
After conductive heat losses through building elements are reduced, convective losses
through draughts are the next major source of energy wastage. The proposal adopts an
airtightness standard of 5.01 m3/h.m2 at 50Pa, with pressure testing of all dwellings to be
undertaken on completion to confirm that the design figure has been met.
Passive design measures and overheating risk mitigation
Glazing should be specified with a solar transmittance value (g-value) to strike the balance
between useful solar gain in the winter and unwanted solar gain in the summer.
Where feasible, dwellings should be fitted with high-efficiency combination boilers, removing
the need for hot water cylinders which would lose useful heat to the dwelling at the rate of
around 1.5kWh/day, or circa 550kWh over the course of a year.
Due to these measures to reduce internal heat gain, natural ventilation provided through
window openings and the opportunity for cross ventilation will allow sufficient air exchange
rates to purge any heat build-up. Active cooling systems are therefore not proposed.
By following these principles the development will be designed to build in resilience to a
potentially changing climate over the lifetime of the buildings and minimise overheating risk,
which can be exacerbated by the drive to build better insulated, more airtight homes if not
considered within the design and construction process.
Low Carbon Heating Systems
All houses will incorporate low carbon heating systems in the form of air source heat pumps.
These operate at around 250% efficiency to deliver heating at a relative carbon intensity of
circa 0.054kgCO2/kWh, a figure which will improve with ongoing grid decarbonisation.
A mains gas option would require a minimum of 0.75 kWp (approximately 3 PV panels) to
achieve the same savings when compared to low carbon heating and hot water technology,
and build in fossil fuel use for the lifetime of the heating system.
For the apartments, exhaust air heat pumps are proposed. Following the fabric first
approach, the heating demand is sufficiently reduced to enable air-to-air heat pumps without
an outdoor unit. This type of unit incorporates a mechanical ventilation with heat recovery
(MVHR) unit with a heat pump in order to first recover heat that is already within the
apartment and then magnify that recovered heat to further increase temperature. No
additional mechanical ventilation would be required on top of that provided by this unit.
11
Energy and Sustainability Statement
Locking Parklands, Weston-super-Mare
February 2021Table 6 . Energy demand of sample dwellings after fabric efficiency and low carbon heat
As Designed Performance
Part L compliant As designed
House Type % Reduc
Reduction
In line with the proposed strategy of achieving a site wide reduction in CO2 emissions of >31% (kWh/yr
(kWh/yr)
Wh/yr ) (kWh/yr
(kWh/yr)
Wh/yr )
through the use of high standards of thermal insulation, air tightness and thermal bridging, Ground Floor Apartment 6030 2741 54.54
in addition to highly efficient low carbon heating and ventilation systems, a site wide
reduction in energy demand of circa 60% is anticipated. Mid Floor Apartment 6202 2498 59.72
Top Floor Apartment 6923 2609 62.31
Table 5 demonstrates the site-wide improvement on Part L compliant energy use and CO2
emissions achieved through energy efficiency measures and low carbon heating systems. Brantwood Detached 7290 3316 54.52
Table 6 demonstrates the improvement on indicative dwelling types.
Caddington Semi-Detached 5978 2458 58.88
Table 5. Site-
Site- wide
wid e energy demand and CO2 emissions after fabric efficiency measures Carlton End-Terrace 6022 2773 53.96
Dalton End-Terrace 6040 2752 54.44
Energy Demand CO2 emissions
(kWh/yr) (kgCO2/yr) Dartmouth Mid-Terrace 7300 2719 62.75
Embleton Detached 7332 2818 61.57
Part L compliant 2,916,241 976,316
Embleton Semi-Detached 7102 2708 61.87
After fabric Foxhill Detached 7326 2802 61.75
1,172,467 544,102
measures and ASHPs
Foxhill Semi-Detached 7253 2744 62.17
kWh/yr % kgCO2/yr % Galby End-Terrace 6925 2707 60.91
Galby Mid-Terrace 6349 2542 59.96
Total site-wide
1,743,797 60.00 432,214 44.27% Henbury Detached 7276 2820 61.24
savings
Henbury Mid-Terrace 6209 2503 59.69
Henbury Semi-Detached 6781 2673 60.58
Lambeth Detached 7776 2968 61.84
Lambeth End-Terrace 7400 2795 62.24
Newton Detached 9041 3416 62.21
Preston Detached 8064 3086 61.73
Preston End-Terrace 7528 2854 62.09
Rye Semi-Detached 7628 3449 54.79
Westbrook Detached 8781 3315 62.25
12
Energy and Sustainability Statement
Locking Parklands, Weston-super-Mare
February 2021unlikely to generate sufficient quantities of electrical energy to be cost effective4. For these
Low Carbon and Renewable Energy Systems reasons wind power is not considered feasible.
The proposed strategy for the development already incorporates low carbon heating
Building Scale Systems
systems, however for completeness a range of alternative and supplementary technologies
have been assessed for potential incorporation into the scheme in accordance with The remaining renewable or low carbon energy systems considered potentially feasible are
Regulation 25A of the Building Regulations and in order to assess which technologies may at a building scale. These are as follows;
support the aspiration to deliver 15% of the site to zero carbon.
• Individual biomass heating
Combined Heat and Power (CHP) and District Energy Networks • Solar thermal
• Solar photo-voltaic (PV)
A CHP unit is capable of generating heat and electricity from a single fuel source. The • Ground Source Heat Pump (GSHPs)
electricity generated by the CHP unit is used to displace electricity that would otherwise be
supplied from the national grid, with the heat generated as effectively a by-product utilised The advantages and disadvantages of these technologies are evaluated in Tables 7-10.
for space and water heating.
The economic and technical viability of a CHP system is largely reliant on a consistent
demand for heat throughout the day to ensure that it operates for over 5000 hours per year.
Heat demand from mainly residential schemes is not conducive to efficient system operation,
with a defined heating season and intermittent daily profile, with peaks in the morning and
the evening. For this reason, the use of a CHP system is considered unfeasible for this
development.
There are currently no heat networks which extend near the proposed development. High
network heat losses associated with distribution to individual houses, as opposed to large
high-rise apartment blocks and commercial developments mean that a new heat network to
serve the area is not considered viable or an environmentally preferred option. Due to these
reasons, the provision for future connection to a district heating system is also not proposed.
Wind Power
Locating wind turbines adjacent to areas with buildings presents a number of potential
obstacles to deployment. These include the area of land onsite required for effective
operation, installation and maintenance access, environmental impact from noise and
vibration, visual impact on landscape amenity and potential turbulence caused by adjacent
obstacles, including the significant amount of woodland on and around the development.
A preliminary examination of the BERR wind speed database indicates that average wind
speeds at 10m above ground level are around 4.6m/s3. Wind turbines at this site are therefore
3 NOABL Wind Map (http://www.rensmart.com/Weather/BERR) 4 CIBSE TM38:2006. Renewable energy sources for buildings.
13
Energy and Sustainability Statement
Locking Parklands, Weston-super-Mare
February 2021Table 7. Individual Biomass Heating feasibility appraisal Table 8. Solar Thermal systems feasibility appraisal
Potential Advantages Risks & Disadvantages Potential Advantages Risks & Disadvantages
• Potential to significantly reduce CO2 • A local fuel supply is required to • Mature and reliable technology • Installation is restricted to favourable
emissions as the majority of space and avoid increased transport emissions offsetting the fuel required for heating orientations on an individual building
water heating will be supplied by a • Fuel delivery, management and water (typically gas) basis
renewable fuel security of supply are critical • Solar thermal systems require relatively • The benefit of installation is limited to
• Decreased dependence on fossil fuel • Space is required to store fuel, a low maintenance the water heating demand of the
supply thermal store and plant • Typically, ~50% of hot water demand in building
• A maintenance regime would be dwellings can be met annually • Safe access must be considered for
required even though modern maintenance and service checks
systems are relatively low • Buildings need to be able to
maintenance accommodate a large solar hot water
• Building users or a management cylinder
company must be able to ensure fuel • Distribution losses can be high if long
is supplied to the boiler as required. runs of hot water pipes are required
Local environmental impacts • Visual impact may be a concern in
potentially include increased NOx and special landscape designations (e.g.
particulate emissions AONB)
Estimated costs and benefits Estimated costs and benefits
• Cost £2,000 upwards for a wood-pellet boiler, not including cost of fuel • Cost £2,000 - 5,000 for standard installation
• Not eligible for RHI payments as new-build properties • Not eligible for RHI payments as new-build properties
• Ongoing offset of heating fuel, minimal maintenance requirements
Conclusions
Conclusions
Biomass heating is considered technically feasible in large dwellings provided sufficient
space can be accommodated for fuel supply, delivery and management. However, local
Solar thermal systems are considered technically feasible on all buildings with suitable
air quality impacts mean they are not a preferred technology.
roof orientations.
14
Energy and Sustainability Statement
Locking Parklands, Weston-super-Mare
February 2021Table 9 . Solar photovoltaic systems feasibility appraisal Table 10
10. Ground Source Heat Pump systems feasibility appraisal
Potential Advantages Risks & Disadvantages Potential Advantages Risks & Disadvantages
• The technology offsets the high carbon • Poor design and installation can lead • Heat pumps are relatively mature • Low temperature heating circuits
content of grid supplied electricity used to lower than expected yields (e.g. technology providing heat using the (underfloor heating) would be required
for lighting, pumps and fans, appliances from shaded locations) reverse vapor compression to maximise the efficiency of heat
and equipment • Installation is restricted to favourable refrigeration cycle pumps
• Mature and well proven technology that orientations • Heat pumps are a highly efficient way • A hot water cylinder would also be
is relatively easily integrated into • Feed in Tariff support mechanism has of providing heat using electricity, required for both space and water
building fabric been discontinued with manufacturers reporting heating
• Adaptable to future system expansion • Safe access must be considered for efficiencies from 320% • Ground source heat pumps are
• Solar resource is not limited by energy maintenance and service checks • Can be of increased benefit where powered by electricity. The current
loads of the dwelling as any excess • Visual impact may be a concern in cooling is also required, therefore carbon factor of electricity as stated in
generation can be transferred to the special landscape designations (e.g. particularly relevant to commercial SAP2012 is 0.519 kgCO₂/kWh and
national grid AONB) or conservation areas buildings compared to a gas heated building this
• PV systems generally require very little can lead to an overall increase in
• Reflected light may be a concern in
maintenance building emissions.
some locations
• Occupiers could benefit from Feed in • It is critical that heat pump systems are
Tariff payments designed and installed correctly to
ensure efficient operation can be
• Service and maintenance requirement
achieved
minimal, and 2-3 storey buildings
should not require significant additional • Ground source heat pumps either
safety measures (mansafe systems etc) require significant land to incorporate a
for roof access. horizontal looped system or significant
expense to drill a bore hole for a
vertical looped system
Estimated costs and benefits
Estimated costs and benefits
• Cost £1,500 upwards (1kWp+) and scalable
• Ongoing offset of electricity fuel costs, minimal maintenance requirements • Cost circa £10,000+
• Shared ground loop approach eligible for non-domestic RHI. Estimated
Conclusions simple payback at circa 18 years (systems only)
• Running cost linked to COP of heat pump, circa 3.0 equates to 66% reduction
PV panels are considered technically feasible for all buildings with suitable roof vs electricity or around 5-6p/kWh (higher than mains gas)
orientations. • Additional costs to upgrade electricity infrastructure currently unknown
The relatively low cost, high carbon saving potential and limited additional impacts Conclusions
mean that PV is considered a feasible option for this development.
Ground source heat pumps are considered technically feasible for buildings in this
scheme. However, the cost and difficulty associated with vertical boreholes at this site
means that they are not considered a preferred low carbon technology at this stage.
15
Energy and Sustainability Statement
Locking Parklands, Weston-super-Mare
February 2021Proposed renewable energy systems
Following this feasibility assessment, it is considered that as biomass heating systems would
lead to air quality concerns and also require significant storage space for fuel and regular
deliveries at different times to all dwellings, they are not appropriate for this development.
Roof-mounted systems are therefore likely to be most suited to the development:
• Solar thermal systems to dwellings that have space to incorporate a hot water
cylinder and a suitable roof orientation.
• Solar photovoltaic modules to dwellings that have suitable roof orientations.
It is considered that solar PV systems are most appropriate in meeting a significant
proportion of energy demand without impacting on the proposed air source heat pump main
heating systems.
Proposed system capacity
It is anticipated that solar photovoltaics may be utilised to deliver the zero carbon aspiration
for 64 of the dwellings. It has been calculated that a total system size of approximately
166kWp could be installed across these dwellings, capable of offsetting an additional 73,146
kgCO2/year.
16
Energy and Sustainability Statement
Locking Parklands, Weston-super-Mare
February 2021Overall Energy and CO2 Reduction Achieved
Through a combination of the described fabric first approach to sustainable construction
and the low carbo n heating systems, the development will deliver energy demand
reductions significantly in exceedance of the requirements Condition 30, through a 60.00%
reduction in energy demand from the Part L baseline
The aspiration to deliver 15% of the development to zero carbon standards would deliver a
a further 5.96% reduction in site wide energy demand through the use of solar PV, resulting
in a total energy reduction from the Part L baseline of 65.96% and carbon savings in excess
of 50%.
Table 11 demonstrates the energy and CO2 reductions achieved.
Table 11 site-wide energy demand and CO2 emissions
11. Total site-
Energy Demand CO2 emissions
(kWh/yr) (kgCO2/yr)
Part L compliant 2,916,241 976,316
After fabric 1,172,467 544,102
measures and ASHPs
After renewable 992,555 457,000
energy
kWh/yr % kgCO2/yr %
Total site-wide 1,923,686 65.96 519,
519,316 53.19%
savings
17
Energy and Sustainability Statement
Locking Parklands, Weston-super-Mare
February 2021Conclusions
This Energy and Sustainability Statement has been prepared on behalf of Keepmoat Homes
South West in support of the application for development of Locking Parklands, Weston-
super-Mare.
The development site is located on the eastern edge of Weston-super-Mare, 5km east of the
town centre. The proposals would deliver 425 dwellings across a mix of two to four bedroom
houses and one and two bedroom apartments, together with circa 300m2 of non-residential
floorspace.
This statement presents a proposed approach to meeting planning policy in relation to
sustainable construction and energy demand reduction contained in Local Plan Policies CS2
and GDP/4, together with Condition 30.
A fabric first approach to sustainable construction is proposed, incorporating improvements
in insulation specification, a reduction in thermal bridging and unwanted air leakage paths
and further passive design measures to ensure that energy demand and consequent CO2
emissions are minimised through the dwelling fabric as a first priority.
The development will avoid the combustion of fossil fuels on site and incorporate air source
heat pumps to all dwellings. Through this approach, a site-wide energy saving of circa 60%
is anticipated.
A range of potential technologies have been assessed for feasibility in meeting the aspiration
to deliver 15% of the site to zero carbon, concluding that solar PV constitutes the preferred
technology for this site. Calculations establish that an installed capacity of 166kWp would be
capable of offsetting approximately 73,146 kgCO2/year.
Through following the approach described, total energy savings equate to 65.96% compared
with a Building Regulations Part L1A 2013 compliant development.
18
Energy and Sustainability Statement
Locking Parklands, Weston-super-Mare
February 2021You can also read
