What is a zero emission neighbourhood?
The ZEN Research Centre, together with its partners, has set out to create zero emission neighbourhoods (ZEN). A zero emission neighbourhood aims to reduce its greenhouse gas emissions towards zero within its life cycle.
In the ZEN Research Centre, a neighbourhood is defined as a group of interconnected buildings with associated infrastructure 1), located within a confined geographical area 2). A zero emission neighbourhood aims to reduce its direct and indirect greenhouse gas (GHG) emissions towards zero over the analysis period 3), in line with a chosen ambition level with respect to which life cycle modules, building and infrastructure elements to include 4). The neighbourhood should focus the following, where the first four points have direct consequences for energy and emissions:
Plan, design and operate buildings and associated infrastructure components towards zero life cycle GHG emissions.
Become highly energy efficient and powered by a high share of new renewable energy in the neighbourhood energy supply system.
Manage energy flows (within and between buildings) and exchanges with the surrounding energy system in a smart and flexible way.5)
Promote sustainable transport patterns and smart mobility systems.
Plan, design and operate with respect to economic sustainability, by minimising total life cycle costs and life cycle system costs.
Plan and locate amenities in the neighbourhood to provide good spatial qualities and stimulate sustainable behaviour.
Development of the area is characterised by innovative processes based on new forms of cooperation between the involved partners leading to innovative solutions.
- Buildings can be of different types, e.g. new, existing, retrofitted or a combination. Infrastructure includes grids and technologies for exchange, generation and storage of electricity and heat. Infrastructure may also include grids and technologies for water, sewage, waste, mobility and ICT.
- The area has a defined physical boundary to external grids (electricity and heat, and if included, water, sewage, waste, mobility and ICT). However, the system boundary for analysis of energy facilities serving the neighbourhood is not necessarily the same as the geographical area.
- The analysis period is normally 60 years into the future, assuming 60 years service life of buildings and 100 years service life of infrastructure, and relevant service life for components that will be replaced.
- The standard NS-EN 15978 “Sustainability of construction works – Assessment of environmental performance of buildings – Calculation method” and the proposed new standard prNS 3720 “Methods for greenhouse gas calculations for buildings”, defines a set of life cycle modules; material production (A1-A3), construction (A4-A5), operation (B1-B7 in NS-EN 15978 and B1-B8 in prNS 3720), end-of-life (C1-C4), and benefits and loads beyond the system boundary (D). NS 3451 «Table of building elements» provides a structured nomenclature checklist of building elements which can be used to define the physical system boundary. A given zero emission neighbourhood should have a defined ambition level with respect to which of these life cycle modules to include, and which building and infrastructure elements to include. It is up to the owner of a ZEN project to decide such an ambition level, but this should be unambiguously defined according to the modulus principle of NS-EN 15978 and prNS 3720. In the FME-ZEN Centre, further work is carried out to clarify what should be the recommended minimum ambition level for ZEN pilot projects. Further work is done to clarify how to calculate CO2 emission gains from local renewable energy production, and the FME-ZEN does not currently bind to the method of emission calculations in NS-EN 15978 and prNS 3720.
- Flexibility should facilitate the transition to a decarbonised energy system and reduction of power and heat capacity requirements.