“ Products themselves do not pollute: it is the factories that made them, the trucks that transported them, the user who uses them and the incinerator that burns them” Pre Consultants
Carbon Dioxide accounts about one third of all the greenhouse gases produced in UK and about 50% of all CO2 emitted is related to our use of buildings as electricity generation relies on the burning of fossil fuels Beyond climate change, the built environment has a variety of broader impacts on our environment through its high consumption of resources; around 30-40% of all raw materials consumed in the UK and other developed economies are used in buildings In the European Union and the U.S, the construction and building sector has been estimated to be responsible for roughly 40% of the overall environmental burden and within the UK non-residential buildings are responsible for 18% of all CO2 emissions Environmental Burden in UK and US
The choice of environmental conditioning system (heating, ventilation and cooling or HVAC) can have a major impact on operating costs, energy efficiency, occupant comfort and environment HVAC accounts for 40% to 60% of the energy used in U.S commercial and residential Buildings. This represents an opportunity for energy savings Energy use for heating and cooling, has long been a target for reduction efforts. For instance, the efficiency of a typical centrifugal chillier has increased 34% over the past 20 years Energy use for space conditioning remains a very large portion of the total national energy use and it still provides significant opportunity for energy use reduction HVAC Systems
Products full life cycle:
Extraction of raw materials
Manufacturing process
Transport
Use
Disposal
Recycling
1969 Industrial Revolution Ian Boustead 1972 Mad Cow Disease 1993-1996 Brent Spar UK
LCA METHODOLOGY
Goal and Scope definition
Life cycle definition
Functional unit
System boundaries
and data quality
requirements
Critical review
process
2. Inventory Analysis Data collection Refining system boundaries Calculation procedures 3. Impact Assessment Category definition Classification Characterization Weighting 4. Interpretation of Results reconsider the definitions and assumptions made in the Goal and Scope definition step
LCA Practitioner Aim of study Strengths Weaknesses Seppo Junnila, The environmental Impact of an office building Throughout its life cycle, 2004 To quantify and compare the potential environmental impact caused by an office building during its life cycle Determining the lifecycle phases and elements that contribute most to the life-cycle impact Life-cycle phases contributed similarly to the environmental impact of the office buildings studied, with building operations dominating the climate change, acidification and eutrophication Impact areas, i.e. resource depletion were not covered or all environmental impact categories considered important, e.g. ozone depletion, particulate matter emissions, radioactive waste, biodiversity, and indoor air quality Difficult to find comprehensive details about life cycle of office buildings: - lack of phases -lack of material inputs -lack of environmental data
“ Buildings are the most long-lived products we make , and LCA tools today don't handle that level of complexity”
The main aim of dealing with limitations of LCA is to ensure that the assessment will be adaptable and applicable to incorporate the socio-economic and environmental aspects of sustainability
Buildings are difficult products for LCA, because the environmental impacts are locally specified
Neighborhood impacts (glare, micro-climate, solar access)
Indoor environment (indoor air quality),
Local ecology (sensitive areas)
Local infrastructure (carrying capacity of
transportation system, water supply)
Limitations of LCA Overcoming Aproaches by Different Practitioners Data collection (avoid assumptions and uncertainties) Use of a toolbox , constructed by several tools where each will deal in different aspects of a given problem . For instance by combining LCIA with Environmental Risk Assessment (ERA), to analyze local problems Helias A. Udo de Haes, et. al System boundaries (which impact indicators and which phases to include in the study to limit resource flows, emissions and life cycle stages) C reation of a ‘hybrid’ analysis which implies that different tools or approaches are connected with one another into hybrid models . These tools will be connected by data flows, but without fully compatibility between the models at stake Helias A. Udo de Haes, et. al Functional Unit (comparisons of two products, life span) Use a ‘socio-economic whole systems’ to establish boundaries and then to create a table to show which sub-systems are appropriate for the LCA study and which have to be excluded International Energy Agency (IEA) et. al Socio-economic & environmental aspects of sustainability Use a database where standardized information can be provided, for instance, extraction, production and manufacturing of materials, about transportations and generation of energy UNEP 1996
LCA has been described as a time-consuming, expensive and complex methodology; however, its usefulness has been extended to long lasting products, such as in buildings materials , building components and building technology because LCA:
investigates how building materials, systems and equipments impact the environment
improves products by comparing them
ensures long life span
contributes to the socio - economical aspects of sustainability, by reducing energy rates and
increasing good quality buildings and services
LCA in BS products can be achieved by:
H av ing a clear goal and scope of the study. It is beter before to apply LCA to research how it has been used from other practitioners in related studies to avoid limitations and uncertainties
Defin ing system boundaries is one of the most importnat steps to avoid uncertainties. Sometimes it is good to limit the study, for instance to examine less indicators and life cycle phases. This will make the study less complicated and time-consuming
Make sure that information can be provided from manufacturers and designers if info cannot be found
from databases
PhD Student Elisavet Dimitrokali School of Built and Natural Environment University of Central Lancashire ( uclan ) Preston PR1 2HE Tel: 01772 893210; Fax: 01772 892916 Email: EDimitrokali@uclan.ac.uk Thank you for your attention!
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