11. Climate Change and Sustainability

Sustainable design and construction standards

11.1 The Councils' plans need to respond to the challenge of mitigating and adapting to our changing climate. The NEC area should be an exemplar in sustainable living, supporting the transition to a zero carbon society in the face of a changing climate.

11.2 Cambridge City Council has set an aspiration in its Climate Change Strategy^[8] for Cambridge to achieve zero carbon status by 2050. South Cambridgeshire District Council has also resolved^[9] to support the transition to "Zero Carbon by 2050" in the next Local Plan.

11.3 Climate change mitigation focuses on designing new communities, infrastructure and buildings to be energy and resource efficient, using renewable and low carbon energy generation and promoting patterns of development that reduce the need to travel by less environmentally friendly modes of transport. Climate change adaptation focuses on ensuring that new developments, including infrastructure, and the wider community are adaptable to our changing climate, including issues such as flood risk and designing buildings and homes using the cooling hierarchy so that they can cope with a warming environment without the need to resort to energy intensive means of cooling. Development should take the available opportunities to integrate the principles of sustainable design and construction into the design of proposals.

11.4 The adopted Local Plans include a range of policies related to climate change adaptation and mitigation for residential and non-residential uses, including approaches to sustainable building design, renewable and low carbon energy, and sustainable drainage systems. There are many similarities, but the two local plans have different approaches on some issues. However, for this cross-boundary site, a single approach for the area covered by this AAP needs to be identified. This could be done by choosing one of the existing Local Plan standards, by combining the standards, or by developing new higher standards reflecting the Councils commitments towards zero carbon. This could be explored further through new evidence that will inform the new joint Local Plan, including consideration of viability implications.

Carbon reduction and Residential Development:

11.5 Given the difference between policy in the adopted Local Plans, it is considered that there are four options that should be explored in relation to carbon reduction from residential development:

• A) a 19% improvement on 2013 Building Regulations (the current Cambridge Local Plan standard); or
• B) a requirement for carbon emissions to be reduced by a further 10% through the use of on-site renewable energy (the current South Cambridgeshire Local Plan standard); or
• C) a 19% improvement on 2013 Building Regulations plus an additional 10% reduction through the use of on-site renewable energy.
• D) consideration of a higher standard and development of further evidence alongside the new joint Local Plan.

11.6 Whilst both options A and B seek improvements above standard development requirements, the advantage of option A over option B is that it promotes an approach to carbon reduction that would focus on making improvements to baseline fabric and energy efficiency requirements, for example through higher performing insulation, before consideration is given to energy generation, an approach that is known as 'fabric first'. While renewable and/or low carbon energy is still likely to play a role in meeting the requirements of this option, it will only be applied once measures to enhance fabric performance and energy efficiency have been considered and applied following the energy hierarchy of Be Lean, Be Clean and Be Green. A further option would be to require a combination of the two, as shown in option C. Alternatively, the Council could explore whether a higher standard is practicable alongside the new joint Local Plan, as shown in Option D.

Sustainable Design and Construction Standards

11.7 The following approach is proposed for all developments in the AAP area.

Residential Development:

• Water efficiency – a maximum of 110 litres/person/day (the current standard in both Local Plans, reflecting the Government's alternative water efficiency standard that can be applied in areas of water stress).

Non-residential development:

• Minimum requirement for achievement of BREEAM 'excellent' with full credits achieved for category Wat 01 of BREEAM. Carbon reduction would be dealt with via the mandatory requirements associated with category Ene 01 of BREEAM.

All development:

• A requirement for all flat roofs to be biodiverse roofs (green or brown) or roof gardens (where roof spaces are proposed to be utilised for amenity space);
• Requirements related to electric vehicle charging infrastructure to support the transition to low emissions vehicles;
• In order to minimise the risk of overheating, all development must apply the cooling hierarchy as follows:
• • Reducing internal heat generation through energy-efficient design;
  • Reducing the amount of heat entering a building in summer through measures such as orientation, shading, albedo, fenestration, insulation and green roofs;
  • Managing heat within the building, e.g. through use of thermal mass and consideration of window sizes;
  • Passive ventilation;
  • Mechanical ventilation;
  • Only then considering cooling systems (using low carbon options).

Overheating analysis should be undertaken using the latest CIBSE (Chartered Institute of Building Services Engineers) overheating standards, with consideration given to the impact of future climate scenarios.

11.8 In order to demonstrate how the principles of sustainable design and construction have been integrated with proposals, sustainability statements will need to be submitted with planning applications, including a site wide Sustainability Statement at the outline planning application stage, which should set overarching targets for the development.

Reviewing Sustainability Standards in the future

11.9 Consideration should also be given to how sustainability targets could be reviewed over time in light of the transition to a zero carbon society. In light of the recent Intergovernmental Panel on Climate Change (IPCC) report on the impacts of global warming of 1.5 degrees above pre-industrial levels, government have asked the Committee on Climate Change to provide advice in relation to the UK's long term carbon reduction targets. This includes options for the date by which the UK should achieve a) a net zero greenhouse gas target and/or b) a net zero carbon target in order to contribute to the global ambitions set out in the Paris Agreement.

11.10 Given the lengthy timescales for development at NEC, it is important to ensure that development in the area supports the road to zero carbon development and for the AAP to be clear that review mechanisms could be built into any planning permissions in order to reflect changes in local and national policy.

Site wide approaches to sustainable design and construction

11.11 The development of NEC should deliver an exemplar of sustainable living. There are many ways in which this requirement can be demonstrated. Development at the scale being considered for the area provides an opportunity for site wide approaches to be taken in the following key areas:

• Energy provision, through the development of decentralised energy systems and innovative approaches to energy infrastructure such as smart energy grids;
• Community scale approaches to water, taking an integrated approach to water management, which gives consideration not just to reducing flood risk but also considers opportunities for water re-use and the wider benefits of managing water close to the surface.
• Application of the BREEAM Communities International Technical Standard to the masterplanning of the site.

11.12 The infrastructure necessary for decentralised energy would need to be explored at a very early stage in consultation with utilities providers, including local authorities, and designed in at the front end of development in order to minimise costs and to appropriately phase the installation with the build out of the development. Consideration should be given to a range of technologies and options for decentralised energy, taking account of future carbon intensity of different energy sources and the decarbonisation of heat, in order that reduction of carbon emissions is secured over the long term. Any proposals for district heat networks should comply with current best practice for district energy by following the guidance set out in the CIBSE/ADE guide "CP1 : Heat Networks: Code of Practice for the UK", in order to ensure that the heat network operates effectively and meets client and customer expectations.

Drainage / SUDS

11.13 The AAP will need to incorporate policy requirements to achieve appropriate sustainable drainage systems (SUDs). The Councils have adopted guidance regarding sustainable drainage design that includes long-term management and maintenance.

11.14 Policies could seek to integrate a SUDs network into the Fen edge landscape that could help to enhance opportunities for specified species as well as providing a sense of place.

Biodiversity

11.15 National planning guidance requires that plans should seek to achieve net gains in biodiversity. The Government started a consultation on 2 December 2018 which proposes that developers could be required to deliver a mandatory 'biodiversity net gain' when building new housing or commercial development – meaning habitats for wildlife must be enhanced and left in a measurably better state than they were pre-development.

11.16 The urban area will require innovative solutions, which preserve and enhance the green infrastructure network, including enhancing existing assets like the First Public Drain. There are opportunities to drive a coordinated approach to extensive biodiverse green roof provision to provide a mosaic of different accessible and inaccessible roof top habitats. It may also be possible to target specific species early on in the design process to help create a sense of place and deliver measurable net gains in a dense urban development. Tree cover also has benefits for urban cooling, as identified in the Cambridge Tree Strategy 2016 to 2026.

11.17 If net gain cannot be achieved fully on site, off site improvements may be required.

SMART Technology

11.18 The Connecting Cambridgeshire Partnership is exploring Smart Cambridge, and ways to improve digital infrastructure. It is exploring transport related programmes on how make better use of data, utilise emerging technology and collaborate with businesses and the community.

11.19 Part of making a sustainable new city district will be ensuring that opportunities are taken to integrate smart technologies from the outset. This could allow city managers of the future to understand in real time transport, energy, air quality and other liveability factors.

Waste Collection

11.20 A fragmented system of waste collection in high density residential areas can lead to reduced recycling rates, increased emissions form collection vehicles, and unsightly bins on the street. An underground system of waste collection like the one at the Eddington Development at North West Cambridge could help address these issues. The 'smart bins' used are only collected when sensors indicate they are almost full, reducing collection vehicles miles.

Supporting Study	Description	Status
North East Cambridge Infrastructure Delivery Plan	A broad assessment of the social and physical infrastructure needed to support the planned development and regeneration of NEC and how these requirements could be met.	To be completed
Development Capacity Study	An assessment of the capacity of the relevant land parcels within NEC to accommodate development (including employment activities, residential and other uses) including the quantum of floorspace and assumed typologies.	To be completed
Health Impact Assessment	An assessment of the health impacts of the proposed policies and proposals of the NEC AAP.	Underway
North East Cambridge AAP Transport Assessment – mitigation measures	An assessment of the effectiveness and cost/benefit of potential mitigation measures for implementation within NEC.	To be completed