Building Energy Efficiency Programs Research Articles

Modeling uncertainty in positive energy districts through a non-probabilistic approach

Positive Energy Districts (PEDs) transcribe an emerging energy transition paradigm for rapid upscaling of building energy efficiency programs to match the urgency of climate mitigation and adaptation. PEDs facilitate pro-active sharing of information and experiences, responsive learning and dissemination, and cooperation across sectors and disciplines. The rapid evolution of technologies for energy efficiency and integration of renewable energy in buildings requires a research-to-design approach. Therefore, it is imperative that a designer makes informed decisions at an early stage of design from an energy-efficiency perspective. However, since PED design involves a significant number of stakeholders, the design parameters could be highly uncertain, which eventually affect the quality of the design solution space. This study uses a bilateral process workflow to quantify risks using a nonprobabilistic technique and a PED roadmap structure. The workflow evaluates different PED scenarios and quantifies the PED potential for the city of Sint-Niklaas in Belgium. The results indicate that risk quantification significantly improves PED decision-making when evaluating collective solutions (district heating) for a district.

Full characterization of building energy factor significance by novel integrated stochastic level-based sensitivity analysis with support vector network and multivariate clustering

Effective planning and targeted implementation of building energy efficiency programs explicitly require robust knowledge on significance pattern of involving factors for precision model-based estimates of potential energy savings. Though extensively adopted for factor significance characterization, prior sensitivity analysis (SA) frameworks fail to capture typical influences attributed to commonly used categorical factors. Moreover, they often assume the assessed factors are independent which can be invalid in many cases to generate misleading outcomes. To overcome these observable defects, this paper develops a novel integrated stochastic level-based sensitivity analysis approach for exhaustively patterning effectual significance of all available building factors of varied type while incorporating diverse factor interactions on validated reliability. While the integration of categorical factors is achieved through factor-type dependent variation levelling, the random factor interactions are apprehended by stochastic sampling and nonlinear support vector network computing to accommodate collinearity trap. Multivariate clustering identifies significance pattern via a composite multi-statistic sensitivity metric derived from stochastic energy responses. Case results of 289 U.S. residential houses validate its utility. This presented approach benefits to perform reliable full sensitivity investigations and analyses under collinearity for building energy systems with verifiable robustness.

Multiple-Benefit Analysis of Scaling-Up Building Energy Efficiency Programs: The Case Study of Tunisia

AbstractThis paper evaluates the benefits of scaling-up energy efficiency and renewable energy programs for the building sector in Tunisia. Both energy and non-energy benefits are quantified using a bottom-up analysis approach to assess economic, environmental, and social impacts of a wide range of energy policies targeting new and existing Tunisian building stocks. The investments required to scale-up programs set to improve the energy efficiency performance of existing building stocks are determined in order to assess both their cost-effectiveness and their impact on the overall energy productivity of Tunisia's economy. The energy productivity analysis is performed to account for both energy and non-energy benefits of building-integrated energy efficiency programs. The energy productivity analysis clearly shows that retrofitting existing building stock has several benefits for Tunisia including reduction of the national energy consumption as well as improvement of the country's overall economy energy efficiency. However, only basic retrofit programs are found to be cost-effective for the private sector to implement with discounted payback periods of less than 5 years. Combined with improving the energy efficiency of new and existing buildings, the installation of rooftop photovoltaic systems for households can significantly lower reliance of Tunisia on imported fuels and improve the energy productivity of its overall economy.

Development of city buildings dataset for urban building energy modeling

Urban building energy modeling (UBEM) is becoming a proven tool to support energy efficiency programs for buildings in cities. Development of a city-scale dataset of the existing building stock is a critical step of UBEM to automatically generate energy models of urban buildings and simulate their performance. This study introduces data needs, data standards, and data sources to develop city building datasets for UBEM. First, a literature review of data needs for UBEM was conducted. Then, the capabilities of the current data standards for city building datasets were reviewed. Moreover, the existing public data sources from several pioneer cites were studied to evaluate whether they are adequate to support UBEM. The results show that most cities have adequate public data to support UBEM; however, the data are represented in different formats without standardization, and there is a lack of common keys to make the data mapping easier. Finally, a case study is presented to integrate the diverse data sources from multiple city departments of San Francisco. The data mapping process is introduced and discussed. It is recommended to use the unique building identifiers as the common keys in the data sources to simplify the data mapping process. The integration methods and workflow are applied to other U.S. cities for developing the city-scale datasets of their existing building stock, including San Jose, Los Angeles, and Boston.

Macro-economic benefit analysis of large scale building energy efficiency programs in Qatar

Abstract This paper evaluates the economic, environmental, and social benefits of large-scale energy efficiency programs for new and existing buildings in Qatar. Using data obtained from detailed energy audits, several proven energy efficiency measures have been analyzed through optimized based analysis to assess their impact on the energy performance for both new and existing buildings in Qatar. Moreover, a bottom-up analysis approach is considered to quantify the multiple benefits for implementing large-scale building energy efficiency programs for the building stock in Qatar. In particular, a more stringent energy efficiency code for the new constructions and three energy retrofit levels for the existing buildings are considered in the analysis. A novel macro-economic analysis using the concept of energy productivity is used to assess the cost-benefit of large-scale energy efficiency programs in Qatar. It is determined that the implementation of a government funded large-scale energy retrofit program for the existing building stock is highly cost-effective in Qatar. In particular, it is found that a large-scale energy efficiency retrofit program of existing buildings can provide a reduction of 11,000 GWh in annual electricity consumption and 2500 MW in peak demand as well as over 5400 kilo-ton per year in carbon emissions. In addition, over 4000 jobs per year can be created when this large-scale energy retrofit program is implemented over 10-year period.

Improving building energy efficiency in India: State-level analysis of building energy efficiency policies

India is expected to add 40 billion m2 of new buildings till 2050. Buildings are responsible for one third of India's total energy consumption today and building energy use is expected to continue growing driven by rapid income and population growth. The implementation of the Energy Conservation Building Code (ECBC) is one of the measures to improve building energy efficiency. Using the Global Change Assessment Model, this study assesses growth in the buildings sector and impacts of building energy policies in Gujarat, which would help the state adopt ECBC and expand building energy efficiency programs. Without building energy policies, building energy use in Gujarat would grow by 15 times in commercial buildings and 4 times in urban residential buildings between 2010 and 2050. ECBC improves energy efficiency in commercial buildings and could reduce building electricity use in Gujarat by 20% in 2050, compared to the no policy scenario. Having energy codes for both commercial and residential buildings could result in additional 10% savings in electricity use. To achieve these intended savings, it is critical to build capacity and institution for robust code implementation.

Comparison of three climatic zoning methodologies for building energy efficiency applications

Climatic zoning for building energy efficiency applications is a key element in many programs and policies to improve thermal performance of buildings. In spite of its importance, there is no consensus about the appropriate methodology for climatic zoning. Previous studies indicate a large variety of methods and parameters are currently used for climatic zoning: degree-days, cluster analysis and administrative divisions are some of the most widely used. This study reports and reviews results obtained with these three methodologies for Nicaragua, a small country in Latin America. Results indicate a high level of agreement between the different methodologies, but they also disagree on the appropriate classification of a significant proportion of the country (37% of Nicaragua’s territory). The three methodologies have strengths and weaknesses, and at present it is impossible to conclude which one is the most appropriate to support building energy efficiency programs and policies. Results of this paper highlight the need for procedures and performance indicators to assess the validity of climatic zoning (which shall be addressed by future studies).

City Building Energy Efficiency Programs: Hindering Real Energy Efficiency? …One Practitioner's Real World Marketplace Observations

ABSTRACTAlthough created with best intentions, several city-run energy efficiency programs actually hinder energy efficiency. The two programs we are familiar with (San Francisco's Energy Performance Ordinance and New York City's Local Law 87) require energy audits on larger commercial buildings. The intent of the programs is to save energy, but the result is instead that energy audits are performed, reports filed, but energy efficiency does not necessarily result. Instead many building owners have told us that they view the ordinance as a tax, and are motivated to pay as little as possible for the audit while fulfilling the ordinance requirements. This has led to a “race to the bottom” on pricing and quality of the resulting energy audits. Audit prices have dropped by over 50% in both markets. Lower costs generally mean less time is devoted to the audit, and the work is done by less experienced and lower cost personnel. This article presents a side-by-side comparison of the differences between a traditio...

Energy productivity evaluation of large scale building energy efficiency programs for Oman

This paper outlines the benefits of large scale energy efficiency programs for new and existing buildings in Oman. In particular, an energy productivity analysis for these programs is carried out to encompass their overall impact for Oman’s economy. Over 75% of the total electricity consumed in Oman is attributed to buildings with almost 50% is due to household. First, a comprehensive optimization analysis is carried out using whole-building energy simulation to determine the best energy efficiency measures suitable to improve the energy performance of buildings in Oman. The economic and environmental benefits of a wide range of energy efficiency technologies are then evaluated. In particular, the impacts of different energy efficiency retrofit levels of existing buildings are the estimated on the energy productivity indicators for the building sector of Oman. The results of the analysis indicate that the implementation of a government funded large scale energy retrofit program for the existing residential building stock is highly cost-effective. In particular, it is found that a basic large scale energy efficiency retrofit program can provide a reduction of 957GWh in annual electricity consumption and 214MW in peak demand as well as over 660k-ton per year in carbon emissions.

Indoor environmental quality research needs for low-energy homes

Potential impacts of low energy homes were reviewed to identify research needs for indoor environmental quality in California's building energy-efficiency programs. California and several nations are planning to implement low-energy or low-carbon requirements for new and existing homes. These homes will be well-insulated, airtight, high-performance buildings, but they will have a narrower margin of safety for control of pollutant sources, moisture, and ventilation. California has a growing fraction of vulnerable persons, such as the elderly and asthmatics. Indoor environmental quality problems will be impacted by climate change, urban densification, and transit-oriented development. Building technology trends expected to affect indoor environmental quality for better or worse include increased use of insulation, thermal mass, fault-detection and diagnostics systems, integrated design, and commissioning. Several studies of low-energy homes have documented problems, such as overheating, poor maintenance of air filters and ventilation systems, and excess noise. Current indoor environmental quality problems requiring further research include attached space infiltration; effective range hood operation; ventilations system commissioning; and builder, operator, and occupant training. An expert panel and stakeholders helped develop a prioritized list of research needs for various determinants of indoor environmental quality. The major drivers and research gaps were related to human behavior, pollutant sources, and integrated design.

Designing building energy efficiency programs for greenhouse gas reductions

Costs and benefits of building energy efficiency are estimated as a means of reducing greenhouse gas emissions in Pittsburgh, PA and Austin, TX. The analysis includes electricity and natural gas consumption, covering 75% of building energy consumption in Pittsburgh and 85% in Austin. Two policy objectives were evaluated: maximize GHG reductions given initial budget constraints or maximize social savings given target GHG reductions. This approach evaluates the trade-offs between three primary and often conflicting program design parameters: initial capital constraints, social savings, and GHG reductions. Results suggest uncertainty in local stocks, demands, and efficiency significantly impacts anticipated outcomes. Annual GHG reductions of 1tonCO2eq/capita/yr in Pittsburgh could cost near nothing or over $20 per capita annually. Capital-constrained policies generate slightly less social savings (a present value of a few hundred dollars per capita) than policies that maximize social savings. However, sectors and end uses targeted for intervention vary depending on policy objectives and constraints. Optimal efficiency investment strategies for some end uses vary significantly (in excess of 100%) between Pittsburgh and Austin, suggesting that resources and guidance conducted at the national scale may mislead state and local decision-makers. Results are used to provide recommendations for efficiency program administrators.