Life cycle analysis in refurbishment of the buildings as intervention practices in energy saving

Rodrigues

Journal of Building Engineering

et al. 2015

a b s t r a c tThis paper describes the implementation of an integrated cost optimality and environmental assessment involving alternative energy efficiency retrofit packages for a building that dates from the beginning of the 20th century. A building typical of the building stock in the centre of Coimbra (located in the central region of Portugal and recently classified as a UNESCO World Heritage Site) was used to illustrate the methodology presented. The results were also analysed for the same building in two other locations. A life-cycle (LC) model was implemented to assess different energy efficiency measures for an apartment. The economic assessment complied with European Directive 2010/31/EU. The results show that the lowest life-cycle environmental impacts were obtained for insulation thicknesses between 50 and 120 mm, which are also cost-optimal. It is also shown that insulation thicknesses of more than 80 mm do not improve energy efficiency or global cost reduction. This paper shows that, even though historic buildings in Portugal do not have to comply with building energy codes, significant energy savings can be achieved for them without changing their historic character. It was also concluded that economic and environmental costs can both be minimised by choosing the most suitable energy efficiency retrofit measures.

Section: Introductionmentioning

confidence: 99%

Energy retrofit of historic buildings: Environmental assessment of cost-optimal solutions

Rodrigues

Journal of Building Engineering

et al. 2015

“…According to some of the studies conducted [10,19,30] the material composition of new residential buildings should have the smallest possible impact on energy consumption and the environment in all phases of its life cycle. Therefore, to determine the environmental impacts of construction materials of the RB before and after the application of insulation, the RB is modelled and evaluated over the phase of usage for periods of one, five, 10 and 20 years, making provision for energy savings (Figure 3e,f).…”

Section: Resultsmentioning

confidence: 99%

“…Even despite the fact that the LCA and its global scope are defined in a set of international standards, the particular methodology depends on the first step, e.g., setting the goals and scope of analysis; therefore, it is necessary to execute LCA studies of residential buildings and their energy demand during the whole life cycle [17,18]. Due to the number of residential buildings and long-term utilization during the year, residential buildings represent an important potential for lowering energy consumption and negative impacts on the environment [19,20].…”

Section: Introductionmentioning

confidence: 99%

Quantification of Improvement in Environmental Quality for Old Residential Buildings Using Life Cycle Assessment

et al. 2016

Abstract:In Slovakia, 35% of buildings are older than 50 years but most newer buildings built before 1990 have greater energy consumption. Some other countries also have similar problems. The growing importance of energy saving in buildings can be, in the case of new and old residential buildings (RB), achieved by lowering thermal energy consumption most often by application of polystyrene insulation on the external walls and roof and the exchange of wood window frames for PVC (polyvinyl chloride) windows. The novelty of the article for Slovakia and some other central European countries consists in using the life cycle assessment (LCA) method for the objective assessment of the environmental benefits of the selected systems of wall insulation, as well as of energy savings in various time intervals of insulation functionality (up to 20 years). LCA software SimaPro (LE Amersfoort, The Netherlands) was used with ReCiPe and IMPACT 2002+ assessment methods to quantify the total environmental impact at selected endpoints and midpoints (IMPACT 2002+) of basic structural materials of an RB and its energy demand-heat consumption (hot water heating, central heating) before the application of insulation and thermal energy saving (TES) after application of insulation to its external walls, roof, and the exchange of windows. The data we obtained confirmed that the environmental impact of the polystyrene insulation of external walls, roof, and exchange of windows of one residential building (RB) in the first year after insulation is higher than the reduction caused by achieving a TES of 39%. When taking a lifespan of 20 years into consideration, the impact over the life cycle of the building materials is reduced by 25% (global warming: −4792 kg CO 2 eq; production of carcinogens: −2479 kg C 2 H 3 Cl eq; acidification: −12,045 kg SO 2 eq; and aquatic eutrophication: −257 kg PO 4 P-lim). The verified LCA methodology will be used for comparative analysis of different variants of thermal insulation of buildings, and their functionality in the long term, while taking into account local specifics and the preparation of environmental product declarations.

“…A number of life cycle carbon analyses has been carried out using real data from case studies, such as those that made static measures of life cycle carbon impacts for existing buildings [12][13][14] and those that assessed the redevelopment of case study buildings in terms of life cycle carbon impact [15,16]. Evidence has not been found of studies that use archetypes to transfer findings from building life cycle carbon impact case studies to a general building stock, particularly considering a broad variety of redevelopment scenarios.…”

Section: Introductionmentioning

confidence: 99%

Evaluation of life cycle carbon impacts for higher education building redevelopment: an archetype approach

Hawkins

Mumovic

2017

Energy and Buildings

An archetype-based approach was taken to generalise findings on the life cycle carbon impacts of higher education building redevelopment, as a follow-up to a previous case study analysis. For each archetype, the life cycle operational and embodied carbon impacts of carbon reduction interventions and building redevelopment options were analysed.A database of English and Welsh university buildings was constructed comprising energy and geometry data. Six archetypes for pre-1985 buildings were then determined based on academic activity and servicing strategy.Buildings were synthesised for each archetype using case study data and the database geometry data. Life cycle carbon models following the BS EN 15978:2011 standard were constructed, calibrated using the database energy data and used to simulate carbon reduction interventions and new-build schemes. Various material systems were considered and design stage uncertainty was factored in.For new-build, average life cycle carbon savings ranged from 37 to 54%, exceeding the range of 25 to 33% for the best-case refurbishment options. However, in some cases the differences were only slight and within the range of uncertainty. Structural systems and building services dominated material impacts, the latter owing to replacement cycles. The generalised findings allowed guidance to be given on higher education carbon management.