Different energy balances for the redesign of nearly net zero energy buildings: An Italian case study

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

“…A net zero energy home has the potential to reduce energy costs [29] while adding to the security of energy supply [30], both of which can be a relative advantage when compared to conventional housing. However, the upfront technology cost remains a barrier [24].…”

Section: Relative Advantage To Existing Technology Barriersmentioning

confidence: 99%

Sustainable Housing: Understanding the Barriers to Adopting Net Zero Energy Homes in Ontario, Canada

2019

Buildings in Canada account for a significant amount of greenhouse gas (GHG) emissions and net zero energy building technology has been identified as part of the solution. This study presents a conceptual model identifying barriers to the adoption of net zero energy housing and tests it by administering a survey to 271 participants in a net zero energy housing demonstration project in Toronto, Canada. Using multivariate correlation and multi-linear regression analyses this study finds that of all the innovation adoption variables it was the construction and design quality that was the most significant contributor to the adoption of a net zero energy home by a potential home owner. This study found that the (a) extra cost compared to a conventional home, b) lack of knowledge about the technology associated with a net zero energy home or (c) not knowing someone who owned a net zero energy home were not significant barriers to accepting net zero energy homes. Our results suggest that policy-makers should promote the diffusion of net zero energy home technology by encouraging housing developers to include net zero energy homes in their collection of model homes, with an emphasis on quality design and construction. Furthermore, engaging in trust building initiatives such as education and knowledge about the technology, its related energy cost savings, and the environmental benefits would contribute to a greater acceptance of net zero energy homes.

“…And finally, once both stages have been completed, it is necessary to analyze the possibility of generating the remaining energy needed by the buildings, or even exporting the surplus of energy when the generation is higher than the consumption. Additionally, the case of building rehabilitation adds greater complexity to the intervention strategies, Maurizio et al [20] analyzed the challenges for existing buildings to reach NZE level.…”

Section: Conventional Procedures For Evaluating Energy Efficiencymentioning

confidence: 99%

Systematic Simplified Simulation Methodology for Deep Energy Retrofitting Towards Nze Targets Using Life Cycle Energy Assessment

et al. 2019

The reduction of energy consumption in the residential sector presents substantial potential through the implementation of energy efficiency improvement measures. Current trends involve the use of simulation tools which obtain the buildings’ energy performance to support the development of possible solutions to help reduce energy consumption. However, simulation tools demand considerable amounts of data regarding the buildings’ geometry, construction, and frequency of use. Additionally, the measured values tend to be different from the estimated values obtained with the use of energy simulation programs, an issue known as the ‘performance gap’. The proposed methodology provides a solution for both of the aforementioned problems, since the amount of data needed is considerably reduced and the results are calibrated using measured values. This new approach allows to find an optimal retrofitting project by life cycle energy assessment, in terms of cost and energy savings, for individual buildings as well as several blocks of buildings. Furthermore, the potential for implementation of the methodology is proven by obtaining a comprehensive energy rehabilitation plan for a residential building. The developed methodology provides highly accurate estimates of energy savings, directly linked to the buildings’ real energy needs, reducing the difference between the consumption measured and the predictions.