A comparison of strategies for mitigation of lifecycle greenhouse gases from residential buildings in the United States

Buildings play a key role in determining global demand for energy and materials, and therefore have a major influence on anthropogenic greenhouse gas (GHG) emissions. This dissertation examines recent trends and future trajectories of energy demand and GHG emissions from residential buildings in the United States. Around 10% of residential GHG emissions in the United States come from material production and construction activities, a share that will increase as energy supply decarbonizes. Decarbonization of electricity generation has been the primary source of residential sector emission reductions since 2005. Demand side energy efficiency improvements have helped to reduce emissions, but compared to transformations in energy supply, their contribution has been minor. In recent decades, reductions in residential energy demand and emissions from energy efficiency and decarbonization were offset by population growth and increases in floor area per person. The types of structures that provide housing services are an important determinant of energy demand and emissions. Both federal and local policies limit supply of multifamily and small-lot single-family structures. An analysis of changes in federal housing policies and their effects on housing construction of different types found that several changes in federal housing policies in the 1970s and 1980s reduced new construction of multifamily housing by 14 million units up to 2015. A separate analysis found that single-family houses consume substantially more energy than multifamily, and that older single family houses consume much more energy for space heating and cooling, while newer single-family houses consume more energy for non-thermal end-uses such as lighting and appliances. Combining estimates of policy effects on housing construction by type, and the effects of house type on residential energy use, overall influences of policy changes on residential energy and GHG emissions in 2015 were estimated. Without the federal policy changes, total urban residential energy demand in 2015 would have been 4.6-8.3% lower, or 27-47% per affected household. Removing policy barriers and disincentives to supply of multifamily housing has large potential for reducing future energy and emissions. Informed by these findings, a highly spatially disaggregated housing stock model was developed and applied to all counties in the United States to analyze scenarios with varying rates of stock turnover, rates of home energy renovation, shares of multifamily housing, and floor area distributions of new housing. An important novelty in this model is the identification of a natural vacancy rate specific to house type and region, and incorporation of a local flexible vacancy rate in housing stock projections. Representation of flexible vacancy rates is particularly important for projecting housing stock growth in regions with low or negative population growth. The housing stock scenarios compare GHG reductions from increased renovation vs increased rates of housing stock turnover, and find that increasing the turnover rate would increase overall residential sector emissions. Energy consumption per floor area is much lower in new buildings due to higher energy efficiency codes and standards, but new single-family houses are generally much larger, which limits the energy reductions from stock turnover. This outcome is very sensitive to the floor area characteristics of housing built in future decades, which in most scenarios are assumed to be unchanged from housing built in the 2010s. Removing houses larger that 3,000 ft2 (279 m2) from new housing supply results in a 25% reduction in the average size of new single-family houses, and produces a 4% reduction in cumulative 2020-2060 emissions. Increasing the share of multifamily housing in new construction, or increasing the rate and depth of energy renovations to existing housing, would produce emission reductions of similar magnitude. Different decarbonization strategies will be optimal in different regions. Regions with older housing are less likely to experience strong future growth, and will rely to a greater extent to renovations of existing housing. Regions with high projected stock growth have a much greater potential to reduce future sectoral emissions by building smaller and more multifamily housing. The single factor with the biggest influence on future residential emissions is the rate at which electricity decarbonizes. A more ambitious combination of efficiency and sufficiency measures in housing supply and renovation, combined with greater decarbonization of electricity supply and material production, is required to achieve sectoral targets consistent with the Paris Agreement or limiting climate change to 1.5-2°C

Plant growth and yield in the Cavendish banana (Musa cavendishii Lamb.) as affected by size and type of planting material

The effect of size and type of planting material on plant growth and yield in the Cavendish banana has been investigated at the Maroochy Experiment Station using "bits" ranging from 1 lb to 6 lb in weight and "suckers" ranging from 10 in. to 20 in. in maximum girth. From a commercial point of view, bits weighing 2-4 lb appear to be the best type of planting material. Where these are not available, "sword" suckers with a corm girth of 12 in. are preferable to either larger or smaller sizes

A study of high-frequency strong ground motion from the San Fernando earthquake

This thesis describes an investigation of the attenuation of strong earthquake ground motion in the 0. 4 to 16 Hz frequency band during the M=6.4, February 9, 1971, San Fernando, California earthquake. It is found that Fourier amplitudes of ground acceleration decay according to a simple expression incorporating a geometric spreading term, and a material attenuation term with constant specific attenuation Q. The scatter in the amplitude data about an expected level given by the simple decay expression is nearly constant with respect to both frequency and focal distance. Fourier amplitudes of acceleration corrected to a reference hypocentral distance agree well with those determined by a two-parameter source model of the San Fernando earthquake. Focusing of energy to the south by the southward propagating rupture is observed at frequencies below 8 Hz. The propagation of rupture was incoherent with respect to higher frequency components. The relationship between intensity of ground motion and site geology is examined. It is found that while, -in general, sedimentary sites were accelerated more strongly than basement rock sites, no clear difference could be found between sedimentary sites classified as "soft" by Trifunac and Brady (1975) (generally recent alluvium) and those classified as having "medium" soil stiffness, generally consisting of older alluvium and sedimentary rock. The difference between amplitudes recorded on basement rock and sediments is more complex. In general, smoothed amplitude spectra from accelerograms recorded on basement rock are lower than smoothed amplitudes at corresponding sedimentary sites. However, basement site spectra show marked isolated peaks, as high as those from sedimentary sites at similar distances. This is attributed to the focusing effects of the irregular topography normally accompanying basement rock outcrops. In the frequency band considered, it is concluded that for the purposes of aseismic design of structures no discrimination should be made between the intensity of ground motion expected on basement rock, sedimentary rock, and coarse-grained alluvium typical of Southern California. The agreement between the recorded strong motion amplitudes and those predicted by a simple two-parameter source model suggests that the model can be used for the assessment of strong ground motion to be used in design procedures. A procedure for estimating design earthquakes using the source model and the amplitude decay expression is presented

A rural agricultural-sustainable energy community model and its application to Felton Valley, Australia

Energy and food security require a delicate balance which should not threaten or undermine community prosperity. Where it is proposed to derive energy from conventional fossil fuel resources (such as coal, shale oil, natural gas, coal seam gas) located in established rural areas, and particularly where these areas are used for productive agricultural purposes, there are often both intense community concern as well as broader questions regarding the relative social, economic and environmental costs and benefits of different land uses and, increasingly, different energy sources. The advent of mainstream renewable energy technologies means that alternative energy options may provide a viable alternative, allowing energy demand to be met without compromising existing land uses. We demonstrate how such a Sustainable Energy Rural Model can be designed to achieve a balance between the competing social goals of energy supply, agricultural production, environmental integrity and social well-being, and apply it to the Felton Valley, a highly productive and resilient farming community in eastern Australia. Research into available wind and solar resources found that Felton Valley has a number of attributes that indicate its suitability for the development of an integrated renewable energy precinct which would complement, rather than displace, existing agricultural enterprises. Modelling results suggest a potential combined annual renewable energy output from integrated wind and solar resources of 1,287 GWh/yr from peak installed capacity of 713 MW, sufficient to supply the electrical energy needs of about 160,000 homes, in combination with total biomass food production of 31,000 tonnes per annum or 146 GWh/yr of human food energy. The portfolio of renewable energy options will not only provide energy source diversity but also ensures long-term food security and regional stability. The Felton Valley model provides an example of community-led energy transformation and has potential as a pilot project for the development of smart distributed grids that would negate the need for further expansion of coal mining and coal fired power stations

Environmental influences on growth, maturation and smoltification in Atlantic salmon parr, Salmo salar

The maturation of Atlantic salmon (Safmo safar) parr, and its effects on growth and smoltification, causes significant economic losses to commercial aquaculture. The current thesis investigates the role of environmental factors on freshwater development, with the aim of providing information which would help reduce the currently observed levels of maturation in farmed salmon. The effects of short day "winter" photoperiods were investigated by exposing three replicated groups of fish to an 8 week "winter" photoperiod (LDlO:14) commencing in May, August or September, in an otherwise continuous light (LD24:0) regime. A further group was held on LD24:0 throughout. 200 to 300 individuals were PIT tagged in each group in order to follow the growth of fish undergoing different developmental strategies, with the retrospective analysis of such development also possible. The highest incidence of maturation (>20%) was observed in the May winter photoperiod group, with low levels recorded in the August and September fish «4%), suggesting that maturation may be influenced during a "critical" period in early development. Maturation levels were intermediate «9%) in the continuous light group indicating that seasonally-changing photoperiodic cues are not necessarily required for gonadal development. The size of mature fish was initially the same as both immature parr and smolts, although the growth of mature individuals subsequently declined, and at the conclusion of the experiment they were significantly smaller. The August photoperiod resulted in the highest incidence of smoltification, with all other treatments resulting in low levels. In a second experiment, PIT tagged fish were reared under an 8 or 12 week ''winter'' photoperiod (LD 10: 14) starting in Mayor June, in an otherwise continuous light (LD24:0) regime. The highest incidence of maturation (> 11 %) was found in the 12 week May fish, with intennediate levels in the 8 week May and 8 week June groups «8%). Low levels were found within the 12 week June group «0.6%) and it is suggested that a critical period when maturation is influenced may occur during a specific, short period in early development. Throughout the experiments, mature individuals maintained the same size as their immature siblings. The 12 week June photoperiod appeared to result in the highest level of smoltification, although those exposed to the 12 week May photoperiod showed the greatest seawater survival. In both photoperiod experiments, fish showing some signs of smoltification were also found to be undergoing gonadal development, indicating that maturation and smoltification are not completely mutually exclusive processes. Possible nutritional effects were considered using different dietary lipid inclusions (either 12.5% or 25%) and variable rations of feed (either full, 2/3 or 113 rations). Different dietary lipid inclusions had no effect on growth, although the whole body fat content of individuals was affected, with a switch in dietary fat content during development resulting in a rapid change in body composition. Fish size increased with ration and, although at the lowest ration of feed whole body fat levels were reduced, they were maintained at a set level under the high and intennediate rations, implying a lipostatic control of growth. Maturation levels were low throughout the nutrition experiments, suggesting that genetic influences may have been important. Dietary lipid level had a negligible effect on smoltification, although increases in ration resulted in a greater incidence of smoltification. Using a 0+ photoperiod regime (i.e. LD24:0 applied from March until December, with the exception of an 8 week period of LD17:7 applied from August), smolting individuals showed a reduction in smolt status when compared to those developed under a natural photoperiod. It is suggested that such regimes restrict the mobilisation of long-tenn energy stores, with the subsequent development of seawater tolerance affected. However, it was noted that the 0+ regime had increased the incidence of smolts. In summary, it has been shown that environmental factors such as photoperiod, nutrition and temperature can play an important role in the developmental strategies taken by juvenile Atlantic salmon. Such factors are likely to greatly influence the attainment of size and/or nutritional thresholds necessary for various developmental strategies, in particular if such thresholds occur during seasonally-sensitive "critical" periods when development can be influenced. Furthermore, the life history strategy undertaken by an individual may be affected by endogenous rhythms, cued by seasonally-changing environmental factors. However, there are clear indications that the underlying genetic control of maturation may also be of importance

The Short Term Intention of Managers to Adopt Internet Commerce After the Tech Wreck: Directions for Research

Electronic commerce has been greeted with much excitement in both the research and wider community over its relatively short lifetime. While many authors have promoted electronic commerce, the “tech wreck” of early 2000 saw a sudden drop in e-commerce uptake. Only a limited amount of research has examined the reasons for the adoption of this technology. This study examines the reasons for commercial technology adoption and applies them to the adoption of internet commerce by Australian companies. The study establishes a set of business reasons for technology adoption, being the desire to gain a competitive advantage, desire to remove a competitive disadvantage, improve communication, reduce organisational costs, improve functionality and a possible bandwagon effect. The study finds that internet commerce adoption may be associated with attempts to attain a competitive advantage, to improve communication. As with many internet commerce adopters, there is evidence of institutional bandwagon effects

Multinationality of UK firms – a longitudinal study based on sales and subsidiaries data

Purpose – This paper aims to contribute to the regionalisation–globalisation debate in international business (IB) by providing a longitudinal analysis of firm-level multinationality. The analysis uses a unique hand-collected data set of both accounting (sales) and non-accounting (subsidiaries) data. The percentage of foreign sales is also used as an additional measure of multinationality. Design/methodology/approach – This paper categorises constituent firms of the Financial Times Stock Exchange 350 index over an 18-year time period from 1998 to 2015. Firms are categorised using the multinationality classification system developed by Aggarwal et al. (2011). The paper also conducts an industrial analysis across ten industries. Findings – The evidence shows increasing multinationality over time that suggests a “trans-regional” operational strategy rather than a global or regional one. The results also show that UK firms are more multinational based on subsidiaries than sales. This contradicts the traditional stages theory of internationalisation where firms first expand sales, then subsidiaries. While some support for triad regions is found, there is also evidence of firm-level operations expanding beyond the triad regions of North America, Asia and Europe to non-triad regions such as Africa, Oceania and South America. The industrial analysis shows that non-service firms are more multinational than service firms. Originality/value – To the best of the authors’ knowledge, this is the first paper to provide an in-depth longitudinal analysis of the geographical dispersion using both sales and subsidiaries data for UK firms. This paper provides a unique perspective on the regionalisation–globalisation debate in IB and presents evidence contrary to traditional stages theories of firm-level internationalisatio