Investigating the Interdependence Between Non-Hydroelectric Renewable Energy,Agricultural Value Added,and Arable Land Use in Argentina

We examine the dynamic relationships between per capita carbon dioxide emissions, real gross domestic product (GDP), non-hydroelectric renewable energy (NHRE) consumption, agricultural value added (AVA), and agricultural land (AGRL) use for the case of Argentina over the period 1980–2013 by employing the autoregressive distributed lag bound approach to cointegration and Granger causality tests. The Fisher statistics of the Wald test are examined, and the existence of a long-run cointegration between variables is proved. There are long-run bidirectional causalities between all considered variables. The short-run Granger causality suggests bidirectional causality between AVA and agricultural land use, unidirectional causalities running from AGRL to NHRE and from NHRE to AVA. Long-run elasticity estimates suggest that increasing AGRL reduces carbon emissions; increasing AVA increases GDP and reduces pollution, AGRL, and NHRE; and increasing NHRE reduces AVA and AGRL. Thus, it seems that agriculture and renewable energy are substitute activities and compete for land use. We recommend that Argentina should continue to encourage agricultural production. The substitutability between agricultural and non-hydroelectric renewable energy productions, and their competition for agricultural land use, should be at least reduced or even stopped by encouraging research and development in second-generation (or even in third-generation) biofuel production and in new technologies for renewable energy and for agriculture more efficient in land use.

     

Meat,Dairy and Climate Change: Assessing the Long-Term Mitigation Potential of Alternative Agri-Food Consumption Patterns in Canada

We use a newly developed model of the entire Canadian energy system (TIMES-Canada) to assess the climate change mitigation potential of different agri-food consumption patterns in Canada. For this, our model has been extended by disaggregating the agricultural demand sector into individual agri-food demands to allow for a more in-depth analysis. Besides a business-as-usual (baseline) scenario, we have constructed four different agri-food scenarios to assess the viability of reducing Canadian meat and dairy consumption in order to diminish Canada’s agricultural sector energy consumption and greenhouse gas (GHG) emissions. Our policy scenarios progressively restrict the consumption of different meat and dairy agricultural products until the year 2030. Our results suggest that the implementation of a meat and dairy consumption reduction policy would lead to a 10 to 40 % reduction in agricultural GHG emissions, depending on the severity of the scenario. This translates to a 1 to 3 % decrease in total Canadian GHG emissions by the year 2030. Besides these environmental benefits, health benefits associated with a reduction in meat and dairy consumption (as inferred from other studies) are presented as an additional source of motivation for implementing such a policy in Canada.     

Assessing the regional impacts of increased energy maize cultivation on farmland birds

The increasing cultivation of energy crops in Germany substantially affects the habitat function of agricultural landscapes. Precise ex ante evaluations regarding the impacts of this cultivation on farmland bird populations are rare. The objective of this paper was to implement a methodology to assess the regional impacts of increasing energy maize cultivation on the habitat quality of agricultural lands for farmland birds. We selected five farmland bird indicator species with varying habitat demands. Using a crop suitability modelling approach, we analysed the availability of potential habitat areas according to different land use scenarios for a real landscape in Northeast Germany. The model was based on crop architecture, cultivation period, and landscape preconditions. Our results showed that the habitat suitability of different crops varied between bird species, and scenario calculations revealed an increase and a decrease in the size of the potential breeding and feeding habitats, respectively. The effects observed in scenario 1 (increased energy maize by 15 %) were not reproduced in all cases in scenario 2 (increased energy maize by 30 %). Spatial aggregation of energy maize resulted in a negative effect for some species. Changes in the composition of the farmland bird communities, the negative effects on farmland bird species limited in distribution and spread and the relevance of the type of agricultural land use being replaced by energy crops are also discussed. In conclusion, we suggest a trade-off between biodiversity and energy targets by identifying biodiversity-friendly energy cropping systems.     

Quantifying net water consumption of Norwegian hydropower reservoirs and related aquatic biodiversity impacts in Life Cycle Assessment

Compared to conventional energy technologies, hydropower has the lowest carbon emissions per kWh. Therefore, hydropower electricity production can contribute to combat climate change challenges. However, hydropower electricity production may at the same time contribute to environmental impacts and has been characterized as a large water consumer with impacts on aquatic biodiversity. Life Cycle Assessment is not yet able to assess the biodiversity impact of water consumption from hydropower electricity production on a global scale. The first step to assess these biodiversity impacts in Life Cycle Assessment is to quantify the water consumption per kWh energy produced. We calculated catchment-specific net water consumption values for Norway ranging between 0 and 0.012 m³/kWh. Further, we developed the first characterization factors for quantifying the aquatic biodiversity impacts of water consumption in a post-glaciated region. We apply our approach to quantify the biodiversity impact per kWh Norwegian hydropower electricity. Our results vary over six orders of magnitude and highlight the importance of a spatial explicit approach. This study contributes to assessing the biodiversity impacts of water consumption globally in Life Cycle Assessment.     

Land Sharing vs Land Sparing to Conserve Biodiversity: How Agricultural Markets Make the Difference

In this paper, we model the supply and demand for agricultural goods and assess and compare how welfare, land use, and biodiversity are affected under intensive and extensive farming systems at market equilibrium instead of at exogenous production levels. As long as demand is responsive to price, and intensive farming has lower production costs, there exists a rebound effect (larger market size) of intensive farming. Intensive farming is then less beneficial to biodiversity than extensive farming is, except when there is a high degree of convexity between biodiversity and yield. On the other hand, extensive farming leads to higher prices and smaller quantities for consumers. Depending on parameter values, it may increase or decrease agricultural producer profits. Implementing “active” land sparing by zoning some land for agriculture and other land for conservation could overcome the rebound effect of intensive farming, but we show that farmers have then incentives to encroach on land zoned for conservation, with higher incentives under intensive farming. We also show that the primary effect of the higher prices associated with extensive farming is a reduction of animal feed production, which has a higher price elasticity of demand, whereas less of an effect is observed on plant-based food production and almost no effect is observed on biofuel production if there are mandatory blending policies.     

Emission-based static traffic assignment models

Tailpipe emissions in the road transportation system are a major source of air pollution and greenhouse gases. One of the possible approaches is to influence drivers’ routing decisions such that the emissions and fuel consumption is minimized. In order to evaluate such condition, we develop environmental traffic assignment (E-TA) models based on user equilibrium (UE) and system optimal (SO) behavioral principles. Extending the traditional travel time-based UE and SO principles to E-TA is not straightforward because, unlike travel time, the rate of emissions increases with the increase in vehicle speed beyond a certain point. The results of various TA models show a network-wide traffic control strategy in which vehicles are routed according to SO-based E-TA, can reduce system-wide emissions. However, a system in which drivers make routing decisions to minimize their own emissions (E-UE system) results in a paradoxical situation of increased individual as well as system-wide emissions.     

Estimation of green house gas emissions from Koteshwar hydropower reservoir,India

The emissions of greenhouse gas (GHG) from soils are of significant importance for global warming. The biological and physico-chemical characteristics of soil affect the GHG emissions from soils of different land use types. Methane (CH₄), nitrous oxide (N₂O), and carbon dioxide (CO₂) production rates from six forest and agricultural soil types in the Koteshwar hydropower reservoir catchments located in the Uttarakhand, India, were estimated and their relations with physico-chemical characteristics of soils were examined. The samples of different land use types were flooded and incubated under anaerobic condition at 30 °C for 60 days. The cumulative GHG production rates in reservoir catchment are found as 1.52 ± 0.26, 0.13 ± 0.02, and 0.0004 ± 0.0001 μg g soil^?1 day^?1 for CO₂, CH₄, and N₂O, respectively, which is lower than global reservoirs located in the same eco-region. The significant positive correlation between CO₂ productions and labile organic carbon (LOC), CH₄ and C/N ratio, while N₂O and N/P ratio, while pH of soils is negatively correlated, conforms their key role in GHG emissions. Carbon available as LOC in the reservoir catchment is found as 3–14% of the total ?C” available in soils and 0–23% is retained in the soil after the completion of incubation. The key objective of this study to signify the C, N, and P ratios, LOC, and pH with GHG production rate by creating an incubation experiment (as in the case of benthic soil/sediment) in the lab for 60 days. In summary, the results suggest that carbon, as LOC were more sensitive indicators for CO₂ emissions and significant C, N, and P ratios, affects the GHG emissions. This study is useful for the hydropower industry to know the GHG production rates after the construction of reservoir so that its effect could be minimized by taking care of catchment area treatment plan.     

Consequential life cycle assessment of automotive material substitution: Replacing steel with aluminum in production of north American vehicles

The substitution of aluminum for steel in vehicle body and closure components is a common strategy for reducing fuel consumption. In order to assess the greenhouse gas (GHG) consequences of this decision, the system must be examined using a life cycle approach. Furthermore, attributional life cycle assessment (ALCA) does not suffice for a number of reasons, including the fact that ALCA does not model the incremental system and that allocating the benefits of recycling inhibits the modelling of system-wide consequences caused by the decision studied. This study thus uses a consequential life cycle assessment (CLCA) framework. We examine the physical and economic processes that guide the North American light-duty vehicle fleet from its initial state in 2012 to a state in 2050. Industry projections are used to model the production and use phases. The system is expanded to include the scrap and material markets. This generates new insights regarding the environmental consequences of changes in scrap generation and recycling in automotive material substitution. The method is applied to the fleet in order to forecast if and when aluminum intensification constitutes net GHG reduction under various conditions. Using baseline parameter values compiled from public and industry data; we calculate a GHG payback period of 25 years, i.e. before a net reduction in emissions relative to a no change counterfactual is achieved. A local sensitivity analysis is performed, showing that the net GHG reduction may be achieved in a period as short as 12 years, or never be achieved at all. A global sensitivity analysis is performed using Monte Carlo simulation, where 16% of trials never reach a net reduction in GHG emissions. We also estimate which parameters contribute the most to variance in the model outcomes. The material replacement coefficient, or the amount of aluminum it takes to functionally replace one kilogram of steel, is the top contributor to the variance (29.8%). Overall, the results are most sensitive to parameters governing the amount of mass that can be replaced by each kilogram of additional aluminum, the GHG intensity of additional aluminum production, and the response of the aluminum scrap and material markets to additional aluminum scrap generation. We conclude that given the current lack of understanding of key parameters and their underlying uncertainties, it is not possible to definitively state that substituting aluminum for steel results in a net reduction in GHG emissions from a fleet of vehicles.     

A dynamic analysis of the global warming potential associated with air conditioning at a city scale: an empirical study in Shenzhen,China

Heating, ventilation and air conditioning (HVAC) systems are a major source of energy consumption in buildings, directly and indirectly contributing to greenhouse gas (GHG) emissions. In the urban environment, and depending on local climatic conditions, air conditioning units attribute to these high energy demands. This study analyzes the use of residential air conditioning units and their associated global warming potential (GWP) between 2005 and 2030 for the city of Shenzhen, a fast-growing megacity located in Southern China. A life cycle assessment approach was adopted to quantify the GWP impacts which arise from both direct (refrigerant release) and indirect (energy consumption) sources, in combination with a materials flow analysis approach. The results show that the total GWP (expressed as carbon dioxide equivalents, CO₂ eq.) from residential air conditioning systems increased from 2.2 ± 0.2 to 5.1 ± 0.4 million tonnes (Mt) CO₂ eq. between 2005 and 2017, with energy consumption and refrigerant release contributing to 72.5% and 27.5% of the total demands, respectively. Immediate measures are required to restrict refrigerant release and reduce the energy consumption of air conditioning units, to help mitigate the predicted additional total emissions of 36.4 Mt. CO₂ eq. potentially released between 2018 and 2030. This amount equals to approximately New Zealand's national CO₂ emissions in 2017. The findings proposed in this study targets air conditioning units to reduce the GWP emissions in cities, and provide useful data references and insights for local authorities to incentivise measures for improving building energy efficiency management and performance.     

An evaluation of alternative household solid waste treatment practices using life cycle inventory assessment mode

Waste disposal is an important part of the life cycle of a product and is associated with environmental burdens like any other life-cycle stages. In this study, an integrated assessment for solid waste treatment practices, especially household solid waste, was undertaken to evaluate the impact contribution of household solid waste treatment alternatives towards the sustainable development by using Life Cycle Inventory Assessment method. A case study has been investigated under various possible scenarios, such as (1) landfill without landfill gas recovery, (2) landfill with landfill gas recovery and flaring, (3) landfill with landfill gas recovery and electric generation, (4) composting, and (5) incineration. The evaluation utilized the Life Cycle Inventory Assessment method for multiple assessments based on various aspects, such as greenhouse gas emission/reduction, energy generation/consumption, economic benefit, investment and operating cost, and land use burden. The results showed that incineration was the most efficient alternative for greenhouse gas emission reduction, economic benefit, energy recovery, and land use reduction, although it was identified as the most expensive for investment and operating cost, while composting scenario was also an efficient alternative with quite economic benefit, low investment and operating cost, and high reduction of land use, although it was identified as existing greenhouse gas emission and no energy generation. Furthermore, the aim of this study was also to establish localized assessment methods that waste management agencies, environmental engineers, and environmental policy decision makers can use to quantify and compare the contribution to the impacts from different waste treatment options.     

The technological innovation of hybrid and plug-in electric vehicles for environment carbon pollution control

Plug-in Hybrid Electric Vehicles (PHEV) have been promoted by providing Vehicle-to-Grid (V2G) infrastructure as a possible solution to reduce greenhouse gas (GHG) and other emissions by utilizing energy instead of oil for effective environmental management. The promising solution for reducing air pollution in cities is commonly regarded as electric vehicles, which helps to optimize the environment management more effectively, as a key to future low carbon mobility. However, their environmental benefits rely on the temporal and spatial sense of real use, and challenges such as limited range complicated for the rollout of an Electric Vehicle (EVs). This paper investigates the environmental carbon pollution in cities and control preventions using Plug-in Hybrid Electric Vehicles (PHEV). Further, the Artificial intelligence model has been introduced, which defines optimal automobile designs and the assignment of vehicles to drivers across a variety of scenarios, including minimum net life cycle expense, GHG emissions, and oil usage for effective environmental management. By designing overspent vehicle power for corresponding output, weight, and cost impact, the life cycle costs and the emission of GHG are reduced utilizing high battery swinging and replacing batteries as needed. Moreover, energy consumption (EC) and pollution have been greatly influenced by the use of energy sources in the environment. The significant energy consumption and pollution variables resulted in a large proportion of coal-fired energy. The results show that the PHEV can achieve better fuel economy by combining the proposed model with an allowable deviation from the state of the charge.     

Accounting for forest carbon pool dynamics in product carbon footprints: Challenges and opportunities

Modification and loss of forests due to natural and anthropogenic disturbance contribute an estimated 20% of annual greenhouse gas (GHG) emissions worldwide. Although forest carbon pool modeling rarely suggests a ‘carbon neutral’ flux profile, the life cycle assessment community and associated product carbon footprint protocols have struggled to account for the GHG emissions associated with forestry, specifically, and land use generally. Principally, this is due to underdeveloped linkages between life cycle inventory (LCI) modeling for wood and forest carbon modeling for a full range of forest types and harvest practices, as well as a lack of transparency in globalized forest supply chains. In this paper, through a comparative study of U.S. and Chinese coated freesheet paper, we develop the initial foundations for a methodology that rescales IPCC methods from the national to the product level, with reference to the approaches in three international product carbon footprint protocols. Due to differences in geographic origin of the wood fiber, the results for two scenarios are highly divergent. This suggests that both wood LCI models and the protocols need further development to capture the range of spatial and temporal dimensions for supply chains (and the associated land use change and modification) for specific product systems. The paper concludes by outlining opportunities to measure and reduce uncertainty in accounting for net emissions of biogenic carbon from forestland, where timber is harvested for consumer products.     

Decomposition of energy consumption and its decoupling with economic growth in the global agricultural industry

The development of mechanization and technology has triggered the growing energy consumption in the agricultural industry. Energy saving in the agriculture industry becomes equally essential with that in the manufacturing, building, and transportation industries. The implementation of reducing energy consumption should be without costing the agricultural production, which is closely related to the food security of human beings. Strong decoupling between energy consumption and economic growth indicates the former decreases while the latter grows, which should be pursued by nations. Therefore, as the first research objective, this study analyzed the decoupling statuses between energy consumption and economic growth in the agricultural industry of 89 countries whose data exist across the period of 2000 to 2016. As a result, only 18 countries have reached strong decoupling. Secondly, this study decomposed agricultural energy consumption in the 89 countries to the effects of a driving factor (i.e., agricultural economic output) and three inhibiting factors (i.e., agricultural land, labor intensity, and energy intensity in descending order). With the identified decoupling statuses, this study provides a substantial understanding of the relationship between agricultural energy consumption and production from a global perspective. Meanwhile, the decomposed factors and corresponding policy implications provide evidence for decision makers of each nation to tailor energy-saving strategies in its agricultural industry.     

Influencing factors of carbon emissions in transportation industry based on CD function and LMDI decomposition model: China as an example

Globally, the transportation industry is one of the leading fields that generate the largest share of greenhouse gas emissions. While undergoing rapid development, countries worldwide aim to solve the problems involved in high energy consumption. Taking China as an example, this paper studies the main factors of carbon emissions in the transport sector and analyses the decoupling states between carbon emission and economic growth, making energy efficiency policies accordingly. In order to better demonstrate the dependence of the economy on the carbon emissions in China's transportation industry comprehensively, combined with the CD production function, this paper develops the decomposition and decoupling technology based on the LMDI approach. Additionally, it quantifies seven effects: energy emission intensity effect, energy structure effect, energy intensity effect, transportation intensity effect, technology state effect, labor input effect and capital input effect. The results show three major points: (1) From 2001 to 2018, the cumulative carbon emissions of China's transportation industry increased by 633.46 million tons, in which the capital input effect is the key factor driving carbon emissions, accounting for 157.70% of the total cumulative increased emissions, followed by energy structure effect at 10.39%. The labor input effect accounted for the smallest proportion at 2.26%. In this case, the technology state effect is the primary factor in restraining carbon emissions. During the study period, it reduced carbon emissions by 292.27 million tons, accounting for 46.14%. To a certain extent, energy intensity effect, transportation intensity effect and energy emission intensity inhibited carbon emissions, representing 16.67%, 5.32% and 2.22%, respectively. (2) During the research period, two decoupling states existed between carbon emissions and economic growth in China's transportation industry, specifically weak decoupling and expansive coupling. (3) The analysis of decomposition and decoupling state of influencing factors of carbon emissions shows that, on the one hand, factors promoting carbon emissions (capital input effect, energy structure effect and labor input effect) hinder the decoupling process. On the other hand, factors restraining carbon emissions (technology state effect, transportation intensity effect, energy intensity effect and energy emission intensity effect) accelerate the decoupling process. The research findings provide a new perspective for achieving carbon emission reduction in the transportation industry and curbing energy consumption growth.     

An evaluation of the environmental costs and benefits of conservation tillage

Every production practice, including conservation tillage, has positive or negative environmental consequences that may involve air, land, water, and/or the health and ecological status of wildlife. The negative impacts associated with agricultural production, and the use of conventional tillage systems in particular, include soil erosion, energy use, leaching and runoff of agricultural chemicals, and carbon emissions. Several of these impacts are quantified. The conclusions suggest that the use of conservation tillage does result in less of an adverse impact on the environment from agricultural production than does conventional tillage, because of reduced surface water runoff and wind erosion. Wildlife habitat will be enhanced to some extent with the adoption of conservation tillage. The benefits to be gained from carbon sequestration will depend on the soil remaining undisturbed. Expansion of conservation tillage on highly erodible land will unquestionably result in an increase in social benefits, but the expected gains will be modest.     

Vegetation dynamics, and land use and land cover change in the Bale Mountains, Ethiopia

Shifts in biological communities are occurring at rapid rates as human activities induced global climate change increases. Understanding the effects of the change on biodiversity is important to reduce loss of biodiversity and mass extinction, and to insure the long-term persistence of natural resources and natures’ services. Especially in remote landscapes of developing countries, precise knowledge about on-going processes is scarce. Here we apply satellite imagery to assess spatio-temporal land use and land cover change (LULCC) in the Bale Mountains for a period of four decades. This study aims to identify the main drivers of change in vegetation patterns and to discuss the implications of LULCC on spatial arrangements and trajectories of floral communities. Remote sensing data acquired from Landsat MSS, Landsat ETM + and SPOT for four time steps (1973, 1987, 2000, and 2008) were analyzed using 11 LULC units defined based on the dominant plant taxa and cover types of the habitat. Change detection matrices revealed that over the last 40?years, the area has changed from a quite natural to a more cultural landscape. Within a representative subset of the study area (7,957.5?km^?2), agricultural fields have increased from 1.71% to 9.34% of the total study area since 1973. Natural habitats such as upper montane forest, afroalpine grasslands, afromontane dwarf shrubs and herbaceous formations, and water bodies also increased. Conversely, afromontane grasslands have decreased in size by more than half (going from 19.3% to 8.77%). Closed Erica forest also shrank from 15.0% to 12.37%, and isolated Erica shrubs have decreased from 6.86% to 5.55%, and afroalpine dwarf shrubs and herbaceous formations reduced from 5.2% to 1.56%. Despite fluctuations the afromontane rainforest (Harenna forest), located south of the Bale Mountains, has remained relatively stable. In conclusion this study documents a rapid and ecosystem-specific change of this biodiversity hotspot due to intensified human activities (e.g., deforestation, agriculture, infrastructure expansion). Specifically, the ecotone between the afromontane and the afroalpine area represent a “hotspot of biodiversity loss” today. Taking into consideration the projections of regional climate warming and modified precipitation regimes, LULCC can be expected to become even more intensive in the near future. This is likely to impose unprecedented pressures on the largely endemic biota of the area.     

Carbon sequestration in reclaimed manganese mine land at Gumgaon, India

Carbon emission is supposed to be the strongest factor for global warming. Removing atmospheric carbon and storing it in the terrestrial biosphere is one of the cost-effective options, to compensate greenhouse gas emission. Millions of acres of abandoned mine land throughout the world, if restored and converted into vegetative land, would solve two major problems of global warming and generation of degraded wasteland. In this study, a manganese spoil dump at Gumgaon, Nagpur in India was reclaimed, using an integrated biotechnological approach (IBA). The physicochemical and microbiological status of the mine land improved after reclamation. Soil organic carbon (SOC) pool increased from 0.104% to 0.69% after 20 years of reclamation in 0–15 cm spoil depth. Soil organic carbon level of reclaimed site was also compared with a native forestland and agricultural land. Forest soil showed highest SOC level of 1.11% followed by reclaimed land and agriculture land of 0.70% and 0.40%, respectively. Soil profile studies of all three sites showed that SOC pool decreased from 0–15, 15–30, and 30–45 cm depths. Although reclaimed land showed less carbon than forestland, it showed better SOC accumulation rate. Reclamation of mine lands by using IBA is an effective method for mitigating CO₂ emissions.     

Urban form and spatial structure as determinants of per capita greenhouse gas emissions considering possible endogeneity and compensation behaviors

Modifying the form and spatial structure of cities through urban planning can be an effective means to reduce greenhouse gas (GHG) emissions in cities. The supporters of the Compact City Approach to urban sustainability propose dense and centralized urban systems. In the case of population density, they argue that it promotes displacements of foot and public transport, and that typical apartments of compact fabrics require less energy than single-family dwellings. Therefore, high density should lead to low GHG emissions. During the last decade this association has been questioned because: a) there may be compensatory behaviors (more energy consumption and more GHG emissions in mobility and housing during weekends and holidays, and b) the fact of not considering the effects of the endogeneity associated with self-selection. In this paper, we analyze population density as a determinant of mobility and residential GHG emissions in Gran Concepción (Chile) using multivariate regression models. The results obtained indicate that density does not exert a significant impact on GHG emissions in mobility and housing. It is income differences that mostly explain individual GHG emissions variability. This calls into question the possible effectiveness of compactness policies in regional, cultural and climatic contexts different from those of the US and Europe and are excessively oriented towards the maintenance and increase of density in urban centers and slowing down the expansion of suburban neighborhoods.     

Estimation of the Thermal Sensitivity of a Dwelling to Variations in Architectural and Behavioural Parameters

The provision of energy for households is a major contributor to greenhouse gas emissions in the domestic sector. There is significant scope for energy savings and thus emission reduction in this sector. This paper constructs a bridge between thermal analysis and environmental assessment in the occupancy stage of the dwelling life cycle, approaching both methods as being on a common system Environment–Dwelling–Inhabitant. The importance of the local level in the thermal analysis and assessment of either a dwelling or an inhabitant's behaviour is demonstrated. It is shown that the researcher can choose between natural experiment, computer experiment and mathematical modelling to analyze the system. Such a choice is discussed for two particular methods of thermal analysis. Thermal Nomograms are the result of mathematical modelling, and the Energy Score Sheet is the result of a computer experiment in energy rating. Despite being developed for the purpose of thermal analysis, these methods can also be utilized for environmental assessment at the local level. The discussion centres on Australian conditions where the majority of the population resides in a relatively benign climate wherein behavioural alterations have significant potential for energy savings and environmental impact. The purpose of the paper is to emphasise benefits apart from energy minimisation to promote the use of energy efficient housing strategies.     

Biofuel use assessments in Africa: Implications for greenhouse gas emissions and mitigation strategies

The energy balances of most African countries suggest that biofuels (woodfuel, crop and wood residues, and dung) constitute the largest share of total energy consumption (up to 97% in some sub-Saharan Africa countries). There is, however, an increasing scarcity of woodfuel (fuelwood and charcoal), the major biofuel, and a feared increase in greenhouse gas (GHG) emissions associated with biofuel combustion. The extent of GHG emissions is estimated from biofuel consumption levels that are in turn based on methodologies that might be inaccurate. A questionnaire, supplemented by informal interviews, are used to collect data, yielding information regarding end-uses, technologies used, scale of consumption, determinants of fuel consumption, and interfuel substitution (among other parameters). The survey revealed that cooking is the major end-use, with other common uses, such as space and water heating. Improved stoves that provide better combustion efficiency and, thus, reduce woodfuel consumption have not been widely disseminated and are associated with higher methane emissions than open fires. More than 90% of the households in Africa use open fires. Consumption is presented as per capita for households and as products and quantity of fuel in the small scale industries, commercial, and public sectors. Among the determinants for biofuel consumption are affordability, availability of the fuel, and interfuel substitutions. Flaws in estimating biofuel consumption yield large uncertainties in GHG emissions, with implications for the development of policies on energy planning and environmental protection. However, the application of scenarios can guide policy formulation.