Energy efficiency in New Zealand's residential sector: A systemic analysis

This paper examines the complexity arising from the multiple, time varying factors that impact energy efficiency in New Zealand's residential sector. Initial problem structuring involved the analysis of behaviour over time of main variables and incorporated stakeholder analysis using a systems approach. Further, a systems model of the problem situation was developed using a participative group model building process. The analysis of the model revealed a set of feedback loops operating in the system identified as responsible for the complexity of the problem situation relating to energy efficiency. The paper concludes by highlighting some of the main results relating to long-term structural changes suggested by the stakeholders involved in this study to change the behaviour of the system.     

Government regulation as an impetus for innovation: Evidence from energy performance regulation in the Dutch residential building sector

The recent implementation of energy performance policy as a way to tackle energy consumption in the building sector in Europe draws attention to the effect it has on the development and diffusion of energy-saving innovations. According to innovation system literature, government regulation through norms and standards is one of the factors stimulating innovation. This paper concentrates on the role of stricter government regulation as an incentive to innovation in the Dutch residential building sector. Innovation in this sector is predominantly a process of applying incremental modifications to comply with new and stricter government regulations and standards. Energy performance policy in its current shape will therefore not contribute to the diffusion of really new innovation in energy techniques for residential buildings in the Netherlands. If diffusion of really new innovation is an explicit aim of energy performance policy then the European wide introduction of this scheme needs reconsideration.     

Effect of building regulation on energy consumption in residential buildings in Korea

According to the International Energy Agency (IEA), the energy demand for the building sector constituted about 25.3% of the final energy use in South Korea. The energy demand for residential buildings counts for 50.3% of the building sector and has also increased by 2.9 percent every year. The Korean government has shifted focus and is now promoting energy efficiency within the building sector and has set long-term energy conservation goals.Despite these efforts to minimize building energy, the Korean government has changed the building regulation to allow remodeling of the balcony space as a living space. Remodeling the balcony space to become an indoor space means that a buffer space for the outdoor environment is lost, causing thermal discomfort and discomfort glare and moreover, increasing the heating and cooling energy demand in residential buildings. Also, it results in an increase in building energy demand in South Korea.In this study, the effect of the alteration of balcony space on the indoor thermal environment and the heating and cooling energy demand of residential buildings in Korea were investigated by field measurement and simulation. From the measurement results, the indoor temperature of the condition without a balcony was 0.8 °C lower than that with a balcony. The heating and cooling load of the unit without the balcony space was 39% and 22% higher, respectively, than that of the unit with the balcony space. This increase results in considerable energy loss in the national scale and the ratio will be 0.3% of the final energy use in Korea. Also, it represents about 1.3% of the final energy use within the building sector of Korea.     

Architectural and urban design potentials for residential building energy saving in the Gulf region

Systematic computer simulations and energy performance studies are conducted for a typical residential building and prevalent conditions in the Gulf region. The studies systematically deal with variations of the main geometrical parameters of the building envelope, comprising plan proportion, orientation, glazing allocation and obstruction. Comparative evaluations and sensitivity analyses expose the effects of these variables and define their relative contributions to prime energy-performance indicators. The combined effectiveness and potentials of the parameters compensate for their limited individual contributions to warrant their practical consideration for passive architectural and urban design application.     

An analysis of energy conservation possibilities in the residential sector in New Zealand

A model which simulates residential energy use in New Zealand until the year 2000 has been developed. This paper describes some of the energy conservation possibilities and their effect on energy use for space and water heating. an engineering analysis made to determine the effect of various factors on energy use for space heating is first described. the information gained from many computer simulations is used to develop a quantitative relationship between space heating energy and major determinants—climatic location, building type and intensity of use. Results from an engineering analysis of a water heating unit are used to establish the energy savings due to improved cylinder insulation and lower storage temperature. A solar space and water heating system is analysed to determine the fraction of total heating load that can be met by harnessing solar energy. the analyses demonstrate that the potential of conservation measures to reduce energy use can be substantial—by raising the insulation level on the building and on the water heating cylinder, by lowering the water storage temperature, and by installing an optimized solar heating system, the energy requirement can be reduced to 0·37 times what it is today for a typical uninsulated home.     

On policy instruments for support of micro combined heat and power

The performance of residential micro combined heat and power (micro-CHP)—a technology to provide heat and some electricity to individual dwellings—is generally dependent on the magnitude of household thermal energy demand. Dwellings with larger and more consistent thermal consumption perform well economically and achieve greater greenhouse gas emissions savings. Consequently, the performance of micro-CHP is dependent on the level of thermal insulation in a dwelling. Therefore, emerging policy approaches regarding energy use in the residential sector, which generally support both energy efficiency measures such as thermal insulation and adoption of micro-CHP, may inadvertently incentivise micro-CHP installation where CO₂ reductions are meagre or not cost-effective. This article examines this issue in terms of the changes in economic and environmental performance that occur for three micro-CHP technologies under changing patterns of residential thermal insulation in the United Kingdom. The results of this analysis are used to comment on the structure of policy instruments that support micro-CHP. It is found that simultaneous support for energy efficiency measures and micro-CHP can be justified, but care must be taken to ensure that the heat-to-power ratio and capacity of the micro-CHP system are appropriate for the expected thermal demand of the target dwelling.     

Stagnating energy efficiency in the Swedish building sector—Economic and organisational explanations

The development towards higher energy efficiency in the Swedish building sector stagnated in the late 1980s and 1990s. In new buildings the average specific energy use for heating is twice as high as in the best performing buildings 20 years ago. By combining econometric studies and interviews with actors in the building sector we analyse the underlying economic and organisational causes for this development. In the stock of buildings, specific energy use for heating (kWh/m²/yr) has a high correlation with increasing energy prices and price elasticities have not changed markedly over time. This implies that the stagnation to a large extent can be explained by energy price trends. On the contrary, in new buildings the correlation between energy prices and specific energy use is much weaker. One important cause of low sensitivity to price changes is that information about the life cycle cost (LCC) of different investment alternatives is often not available to the involved actors. The most common investment criterion is instead the requirements of the national building energy standard which has developed into a norm rather than a minimum for energy performance. In this paper we also discuss potential improvements in the learning processes within the sector.     

Energy saving potential in the residential sector of Uzbekistan

In 2003, the residential sector of Uzbekistan has consumed about 15.073 Mtoe (million ton of oil equivalent) of energy or 27.3% of the total energy consumed in the country. This value is approximately twice as much as that of residential sector of Turkey and Romania. The climate of above countries is comparable to that of Uzbekistan. In this article we suggest to use the heating degree-day method for determining the natural gas consumption norms for residential heating. Taking the climatic differences into account, the norms of natural gas consumption in respect to each resident are submitted for each region of Uzbekistan. The realization of suggested proposals allows saving about 9.2 billion m³ of natural gas annually.     

The potential for energy efficiency gains in the Canadian commercial building sector: A stochastic frontier study

The achievement of energy efficiency in commercial buildings is a function of the activities undertaken, the technology in place, and the extent to which those technologies are used efficiently. We study the factors that affect efficient energy use in the Canadian commercial sector by applying a stochastic frontier approach to a cross-section of Canadian commercial buildings included in the Commercial and Institutional Building Energy Use Survey (CIBEUS). Structural and climate-control features of the buildings as well as climatic conditions are assumed to determine the location of the frontier, while management-related variables including such factors as ownership type and activities govern whether or not the maximally attainable efficiency along the frontier is achieved. Our results indicate that although, on average, buildings appear to be fairly efficient, certain types of operations are more likely than others to exhibit energy efficiencies that are significantly worse than average. These results, along with those related to the effects of physical characteristics on the stochastic efficiency frontier, suggest that there is scope for focused policy initiatives to increase energy efficiency in this sector.     

Long-term energy savings and greenhouse gas emission reductions in the Swiss residential sector

The aim of this paper is to explore the possibilities to reach two long-term targets regarding energy consumption and greenhouse gas emissions of the Swiss residential building stock: a reduction of the final energy consumption by a factor of 3 and of _CO2${\mathrm{CO}}_2$ emissions by a factor of 5 until 2050. A model is constructed to describe the dynamics of the energy-relevant properties of the residential building stock. Appropriate scenarios are discussed in terms of decisions made during construction or renovation of residential buildings which affect heat demand and determine the energy carriers used for heating and hot water generation. We show that both targets could be reached, although ambitious efforts are necessary. The central element of a successful strategy is to reduce the specific heat demand of existing buildings during renovation and to substitute the heating and hot water systems by less carbon intensive ones. Our results suggest that there is more flexibility to reach the emission target than the energy reduction target.     

Compact fluorescent lighting and residential natural gas consumption: Testing for interactive effects

Replacing incandescent light bulbs with compact fluorescents (CFLs) has traditionally been seen as a cost effective means of promoting energy conservation. Recently, however, the magnitude of energy savings associated with CFLs has been called into question. Specifically, recent findings suggest an “interactive effect” associated with the replacement of incandescent light bulbs with CFLs in the residential sector. In this scenario, the reduced wattage of CFLs, relative to incandescent bulbs, generates less heat, which in turn, requires additional natural gas usage during the heating season. Engineering studies suggest the magnitude of the effect is significant in energy terms, which implies that the energy savings associated with CFLs may be significantly overstated. In this paper, we use billing analysis to test for the presence of interactive effects. Our analysis is based on a comprehensive dataset that includes monthly household electricity and natural gas usage, the number of CFL bulbs installed, the installation date, and a set of household characteristics. Our results suggest that CFLs do indeed save electricity. However, we do not find any support for the hypothesis that CFLs cause increased usage of natural gas.     

Economic optimization and sensitivity analysis of energy requirements in residential space heating

An analytical model which relates performance with costs of additional insulation has been developed and the optimum set of insulation values for the various surfaces of a new building has been determined in a generalized form. On this basis the determinants of the specific energy requirements, corresponding to an optimal level of insulation are identified. The sensitivity of the energy needs to variations in the building structure or design, in the economic conditions, and in the climate characteristics, is also investigated.     

Efficiency and the role of government in energy policy

It is well established that the presence of a monopolist producer removes efficiency from the world oil market. Efficiency in energy resource utilization can nevertheless be the proclaimed objective of an energy policy by an oil-importing nation if imported oil is considered a non-produced resource available at a given price. This article presents an example of such a policy which consists of the institution of price guarantees for energy alternatives and of government subsidies for the development of new energy technologies. We illustrate how this policy will attain efficiency, and the ratio of benefits to the costs associated with its adoption are calculated.     

Electricity end-uses in the residential sector of Brazil

The residential energy consumption has been studied in many countries as it usually accounts for a large percentage of the total energy consumption. Energy end-uses have also been a matter of concern as they can assist energy system planning. The objective of this paper is to assess the actual scenario of electricity consumption and estimate electricity end-uses in the residential sector of Brazil for different bioclimatic zones. The analysis is based on a survey performed by 17 energy utilities enclosing a total of 17,643 houses or flats over 12 states in Brazil. The survey was performed to obtain electricity consumption data for all household appliances found in houses and flats. The electricity end-uses were estimated by performing weighted averages according to the location of the dwellings in each bioclimatic zone. Results indicate that the largest end-uses are for refrigerator and freezer together, which account for about 38–49% of the electricity consumption in dwellings in Brazil. Air-conditioning and electric shower are the end-uses that are more dependent on the climatic conditions. The main conclusion that can be made from the analysis is that air-conditioning should be a major concern in the residential sector of Brazil in the near future as its ownership is still low, but its electricity consumption is already significant mainly over summer.     

A method of identifying and weighting indicators of energy efficiency assessment in Chinese residential buildings

This paper describes a method of identifying and weighting indicators for assessing the energy efficiency of residential buildings in China. A list of indicators of energy efficiency assessment in residential buildings in the hot summer and cold winter zone in China has been proposed, which supplies an important reference for policy makings in energy efficiency assessment in buildings. The research method applies a wide-ranging literature review and a questionnaire survey involving experts in the field. The group analytic hierarchy process (group AHP) has been used to weight the identified indicators. The size of survey samples are sufficient to support the results, which has been validated by consistency estimation. The proposed method could also be extended to develop the weighted indicators for other climate zones in China.     

Prediction of greenhouse gas reduction potential in Japanese residential sector by residential energy end-use model

A model is developed that simulates nationwide energy consumption of the residential sector by considering the diversity of household and building types. Since this model can simulate the energy consumption for each household and building category by dynamic energy use based on the schedule of the occupants’ activities and a heating and cooling load calculation model, various kinds of energy-saving policies can be evaluated with considerable accuracy. In addition, the average energy efficiency of major electric appliances used in the residential sector and the percentages of housing insulation levels of existing houses is predicted by the “stock transition model.” In this paper, energy consumption and CO₂ emissions in the Japanese residential sector until 2025 are predicted. For example, as a business – as-usual (BAU) case, CO₂ emissions will be reduced by 7% from the 1990 level. Also evaluated are mitigation measures such as the energy efficiency standard for home electric appliances, thermal insulation code, reduction of standby power, high-efficiency water heaters, energy-efficient behavior of occupants, and dissemination of photovoltaic panels.     

Energy efficiency in the Hellenic building sector: An assessment of the restrictions and perspectives of the market

The significance of bioclimatic architecture has become widely accepted since the 1970s and the implementation of its principles in practice is a key factor in order to achieve energy efficiency in the building sector. The way, however, from scientific acceptance to commercial utilization is not a straightforward one. This paper deals with the notion of bioclimatic architecture in buildings and investigates the aspects of this concept in Hellas. A sample of university researchers, building contractors and members of public organisations was interviewed using a standardised set of guidelines. The barriers to promoting bioclimatic design, role of the local government in the adoption process, level of environmental culture as well as perspectives of this concept in Hellas were the key areas of discussion in each of the interviews. The results from the data analysis reveal insufficient economic incentives, a lack in technical information as well as a lack in specific environmental policies that would foster the propagation of bioclimatic architecture.     

Life cycle energy analysis of a residential building with different envelopes and climates in Indian context

In this paper life cycle energy (LCE) demand of a residential building of usable floor area about 85.5 m² located at Hyderabad (Andhra Pradesh), India is evaluated under different envelopes and climates in Indian context. The house is studied with conventional (fired clay) and alternative wall materials (hollow concrete, soil cement, fly ash and aerated concrete) under varying thickness of wall, and insulation (expanded polystyrene) on wall and roof. The house is modelled for five different climatic zones of India, i.e. hot and dry, warm and humid, composite, cold and moderate. Study suggests that alternative wall materials alone (without insulation) reduce LCE demand of the building by 1.5-5%. Aerated concrete (AC), as wall material, has better energy performance over other materials. LCE savings are significant when insulation is added to external wall and roof. It varies from 10% to 30% depending on the climatic conditions. Maximum LCE savings with insulation are observed for warm and humid climate and least for moderate climate. For same thickness of insulation, LCE savings are much more with roof insulation than wall insulation. But wall insulation is found to be preferable to a thicker wall. It is also observed that there is a limit for thickness of insulation that can be applied on external walls and roof from life cycle point of view. This limit is found to be about 10 cm for composite, hot and dry, warm and humid, and cold climates and 5 cm for moderate climate.     

Efficient and inefficient aspects of residential energy behaviour: What are the policy instruments for change?

The empirical part of this study is based on a survey of 600 Swedish households and a number of interviews where questions about residential energy behaviour and possible policy instruments for change were raised. The study provides insight into current behavioural patterns and gives a bottom-up perspective on the realistic perspective potentials for change and ways to achieve them. Residential energy use accounts for a fifth of the total in Northern nations and patterns of behaviour may influence levels of energy use to the same extent as choice of appliances. The study revealed those behavioural patterns that are efficient and those that need to be improved for energy conservation. Several policy instruments for change were identified in the study and they include combinations of information, economic measures, administrative measures and more user friendly technology as well as equipment with sufficient esthetic quality. Policy instruments that have fostered energy efficient behaviour in Sweden include the massive information campaigns during the oil crises in the 1970s as well as energy labelling of appliances. Still, many households are “energy-unaware” and several energy efficient behaviours are motivated not by energy conservation concern but of a perceived lack of time. This shows that it is important to have a broad perspective in energy conservation, to evaluate trends and to use policy instruments timely to support or discourage them.