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Hypoxia modeling in Corpus Christi Bay using a hydrologic information system
textHypoxia is frequently detected during summer in Corpus Christi Bay, Texas, and causes significant harm to benthic organism population and diversity. Hypoxia is associated with the density stratification in the Bay but the cause of stratification is uncertain. To support the study of hypoxia and stratification, a cyberinfrastructure based on the CUAHSI (Consortium of Universities for the Advancement of Hydrologic Science, Inc) Hydrologic Information System (HIS) is implemented. HIS unites the sensor networks in the Bay by providing a standard data language and protocol for transferring data. Thus hypoxia-related data from multiple sources can be compiled into a structured database. In Corpus Christi Bay, salinity data collected from many locations and times are synthesized into a three-dimensional space-time continuum using geostatistical methods. The three dimensions are the depth, the distance along a transect line, and time. The kriged salinity concentration in space and time illuminates the pattern of movement of a saline gravity current along the bottom of the Bay. The travel time of a gravity current in the Bay is estimated to be on the order of one week and the speed is on the order of 1 km per day. Statistical study of high-resolution wind data shows that the stratification pattern in the Bay is related to the occurrence of strong, southeasterly winds in the 5 days prior to the observation. This relationship supports the hypothesis that stratification is caused by the wind initiating hypersaline gravity currents which flow from Laguna Madre into Corpus Christi Bay. An empirical physical hypoxia model is created that tracks the fate and transport of the gravity currents. The model uses wind and water quality data from real-time sensors published by HIS to predict the extent and duration of hypoxic regions in the Bay. Comparison of model results with historical data from 2005 to 2008 shows that wind-driven gravity currents can explain the spatially heterogeneous patterns of hypoxic zones in Corpus Christi Bay.Civil, Architectural, and Environmental Engineerin
Dynamic modelling of the socio-technical systems of household energy consumption and carbon emissions
There is a growing need to curtail the carbon emissions in the globe in order to
achieve the climate stabilisation goals based on the climate change threat. And as
such, different initiatives and schemes of Government have targeted a number of
policies at reducing energy and carbon emissions targets with the housing sector of
the economy not an exception. In order to explore the feasibility of achieving carbon
emissions reduction targets within the housing sector of the UK, the research views
the issue of household energy consumption and carbon emissions as complex sociotechnical
problem involving the analysis of both the social and technical variables.
This thesis therefore describes the development of the system dynamics based model
to capture and solve the problem relating to the future profiles of household energy
consumption and carbon emissions by providing a policy advice tool for use by the
policy makers.
In order to investigate the problem, the research adopts the pragmatist research
strategy involving collection of both qualitative and quantitative data to develop the
model. The developed model has six modules, which are: population/household,
dwelling internal heat, occupantsâ thermal comfort, climatic-economic-energy
efficiency interaction, household energy consumption, and household CO2 emissions.
In addition to the âbaselineâ scenario, the developed model was used to develop four
illustrative scenarios of household energy consumption and carbon emissions; which
are: âefficiencyâ scenario, âbehavioural changeâ scenario, âeconomicâ scenario, and
âintegratedâ scenario. The âefficiencyâ scenario generally considers the effects of
improvements in energy efficiency measures on household energy consumption and
ultimately on household carbon emissions. Additionally, the âbehavioural changeâ
scenario tries to model the effects of occupantsâ change of energy consumption
behaviour on household energy consumption and carbon emissions profile. The
âeconomicâ scenario assumes a case of policy change by Government favouring
energy prices reduction, thereby reducing the energy bills payable by the
householders and its consequences on household energy consumption and carbon
emissions. And the âintegratedâ scenario combines the assumptions in the first three
scenarios and then analyses its effects on household energy consumption and carbon
emissions.
The âbaselineâ results indicate that about 49% savings in carbon emissions by the
year 2050 below the base year of 1990 are possible. Additionally, the results of the
developed model for all the illustrative scenarios indicate that carbon emissions
savings of 46%, 55%, 58%, and 63% below the base year of 1990 are possible from
the âeconomicâ, âefficiencyâ, âbehavioural changeâ, and âintegratedâ scenarios
respectively.
The research concludes that it is unlikely for any of the scenarios by its own to meet
the required legally binding reductions of 80% cut in carbon emissions by 2050
unless this is vigorously pursued. The unique contribution of the research is the
development of a model that incorporates socio-technical issues that can be used for
decision making over time
Collinsville solar thermal project: energy economics and dispatch forecasting (final report)
The primary aim of this report is to help negotiate a Power Purchase Agreement (PPA) for the proposed hybrid gas-Linear Frensel Reflector (LFR) plant at Collinsville, Queensland, Australia. The reportâs wider appeal is the discussion of the current situation in Australian National Electricity Market (NEM) and techniques and methods used to model the NEMâs demand and wholesale spot prices for the lifetime of the proposed plant.
Executive Summary
1 Introduction
This report primarily aims to provide both dispatch and wholesale spot price forecasts for the proposed hybrid gas-solar thermal plant at Collinsville, Queensland, Australia for its lifetime 2017-47. These forecasts are to facilitate Power Purchase Agreement (PPA) negotiations and to evaluate the proposed dispatch profile in Table 3. The solar thermal component of the plant uses Linear Fresnel Reflector (LFR) technology. The proposed profile maintains a 30 MW dispatch during the weekdays by topping up the yield from the LFR by dispatch from the gas generator and imitates a baseload function currently provided by coal generators. This report is the second of two reports and uses the findings of our first report on yield forecasting (Bell, Wild & Foster 2014b).
2 Literature review
The literature review discusses demand and supply forecasts, which we use to forecast wholesale spot prices with the Australian National Electricity Market (ANEM) model.
The review introduces the concept of gross demand to supplement the Australian Electricity Market Operatorâs (AEMO) âtotal demandâ. This gross demand concept helps to explain the permanent transformation of the demand in the National Electricity Market (NEM) region and the recent demand over forecasting by the AEMO. We also discuss factors causing the permanent transformation. The review also discusses the implications of the irregular ENSO cycle for demand and its role in over forecasting demand.
Forecasting supply requires assimilating the information in the Electricity Statement of Opportunities (ESO) (AEMO 2013a, 2014c). AEMO expects a reserve surplus across the NEM beyond 2023-24. Compounding this reserve surplus, there is a continuing decline in manufacturing, which is freeing up supply capacity elsewhere in the NEM. The combined effect of export LNG prices and declining total demand are hampering decisions to transform proposed gas generation investment into actual investment and hampering the role for gas as a bridging technology in the NEM. The review also estimates expected lower and upper bounds for domestic gas prices to determine the sensitivity of the NEMâs wholesale spot prices and plantâs revenue to gas prices.
The largest proposed investment in the NEM is from wind generation but the low demand to wind speed correlation induces wholesale spot price volatility. However, McKinsey Global Institute (MGI 2014) and Norris et al. (2014a) expect economically viable energy storage shortly beyond the planning horizon of the ESO in 2023-24. We expect that this viability will not only defer investment in generation and transmission but also accelerate the growth in off-market produced and consumed electricity within the NEM region.
2.1 Research questions
The report has the following overarching research questions:
What is the expected dispatch of the proposed plantâs gas component given the plantâs dispatch profile and expected LFR yield?
What are the wholesale spots prices on the NEM given the plantâs dispatch profile?
The literature review refines the latter research question into five more specific research questions ready for the methodology:
What are the half-hourly wholesale spots prices for the plantâs lifetime without gas as a bridging technology?
Assuming a reference gas price of between 7.19/GJ for base-load gas generation (depending upon nodal location;) and
for peak-load gas generation of between 8.99/GJ; and
given the plantâs dispatch profile
What are the half-hourly wholesale spots prices for the plantâs lifetime with gas as a bridging technology?
Assuming some replacement of coal with gas generation
How sensitive are wholesale spot prices to higher gas prices?
Assuming high gas prices are between 9.71/GJ for base-load gas generation (depending upon nodal location); and
for peak-load gas generation of between 12.14/GJ; and
What is the plantâs revenue for the reference gas prices?
How sensitive is the plantâs revenue to gas as a bridging technology?
How sensitive is the plantâs revenue to the higher gas prices?
What is the levelised cost of energy for the proposed plant?
3 Methodology
In the methodology section, we discuss the following items:
dispatch forecasting for the proposed plant;
supply capacity for the years 2014-47 for the NEM;
demand forecasting using a Typical Meteorological Year (TMY); and
wholesale spot prices calculation using ANEM, supply capacity and total demand
define three scenarios to address the research questions:
reference gas prices;
gas as a bridging technology; and
high gas prices.
The TMY demand matches the solar thermal plantâs TMY yield forecast that we developed in our previous report (Bell, Wild & Foster 2014b). Together, these forecasts help address the research questions.
4 Results
In the results section we will present the findings for each research question, including
the TMY yield for the LFR and the dispatch of the gas generator given the proposed dispatch profile in Table 3;
Average annual wholesale spot prices from 2017 to 2047 for the plantâs node for:
Reference gas prices scenario from 38/MWh
Gas as a bridging technology scenario from 110/MWh
High gas price scenario from 41/MWh
The combined plants revenue without subsidy given the proposed profile:
Reference gas price scenario 52 million
High gas price scenario $47 million
5 Discussion
In the discussion section, we analyse:
reasons for the changes in the average annual spot prices for the three scenarios; and
the frequency that the half-hourly spot price exceeds the Short Run Marginal Cost (SRMC) of the gas generator for the three scenarios for:
day of the week;
month of the year; and
time of the day.
If the wholesale spot price exceeds the SRMC, dispatch from the gas plant contributes towards profits. Otherwise, the dispatch contributes towards a loss. We find that for both reference and high gas price scenarios the proposed profile in Table 3 captures exceedances for the day of the week and the time of the day but causes the plant to run at a loss for several months of the year. Figure 14 shows that the proposed profile captures the exceedance by hour of the day and Figure 16 shows that only operating the gas component Monday to Friday is well justified. However, Figure 15 shows that operating the gas plant in April, May, September and October is contributing toward a loss. Months either side of these four months have a marginal number of exceedances. In the unlikely case of gas as a bridging scenario, extending the proposed profile to include the weekend and operating from 6 am to midnight would contribute to profits.
We offer an alternative strategy to the proposed profile because the proposed profile in the most likely scenarios proves loss making when considering the gas componentâs operation throughout the year. The gas-LFR plant imitating the based-load role of a coal generator takes advantage of the strengths of the gas and LFR component, that is, the flexibility of gas to compensate for the LFRâs intermittency, and utilising the LFRâs low SRMC. However, the high SRMC of the gas component in a baseload role loses the flexibility to respond to market conditions and contributes to loss instead of profit and to CO2 production during periods of low demand.
The alternative profile retains the advantages of the proposed profile but allows the gas component freedom to exploit market conditions. Figure 17 introduces the perfect dayâs yield profile calculated from the maximum hourly yield from the years 2007-13. The gas generator tops up the actual LFR yield to the perfect dayâs yield profile to cover LFR intermittency. The residual capacity of the gas generator is free to meet demand when spot market prices exceed SRMC and price spikes during Value-of-Lost-Load (VOLL) events. The flexibility of the gas component may prove more advantageous as the penetration of intermittent renewable energy increases.
6 Conclusion
We find that the proposed plant is a useful addition to the NEM but the proposed profile is unsuitable because the gas component is loss making for four months of the year and producing CO2 during periods of low demand. We recommend further research using the alternative perfect dayâs yield profile.
7 Further Research
We discuss further research compiled from recommendation elsewhere in the report.
8 Appendix A Australian National Electricity Market Model Network
This appendix provides diagrams of the generation and load serving entity nodes and the transmission lines that the ANEM model uses. There are 52 nodes and 68 transmission lines, which make the ANEM model realistic. In comparison, many other models of the NEM are highly aggregated.
9 Appendix B Australian National Electricity Market Model
This appendix describes the ANEM model in detail and provides additional information on the assumptions made about the change in the generation fleet in the NEM during the lifetime of the proposed plant
Farming smarter, not harder: securing our agricultural economy
In the context of rising global demand, resource scarcity, and environmental pressures, this report considers the future of Australian agriculture.
Global populations are growing and food prices are skyrocketing. This creates new market opportunities for Australian agriculture. But Australia has fragile and vulnerable soils, which are being degraded at an unsustainable rate.
If we continue with âbusiness as usualâ, we will keep losing soils faster than they can be replaced. Acting now to improve soil condition could increase agricultural production by up to 2.1 billion per year. It could also help farmers cut costs on fertiliser and water use.
âWinners of the food boom will be countries with less fossil fuel intensive agriculture, more reliable production, and access to healthy land and soilsâ said the reportâs lead author Laura Eadie. âHow we manage our land and soils will be key to whether Australia sees more of the upsides or downsides of rising global food demand.â
Farming Smarter, Not Harder finds that Australian agriculture can build a lasting competitive advantage through innovation that raises agricultural productivity, reduces fuel and fertiliser dependence, and preserves the environment and resources it draws on. To achieve this, Australia needs to:
Invest in knowledge: increase government investment in research and development by up to 7% a year; increase funding for extension programs; implement the Productivity Commissionâs recommendation to set up Rural Research Australia; fund the national soil health strategy with an endowment sufficient to support ongoing research and monitoring for at least 20 years.
Stop chopping and changing support for regional natural resource management:
Federal and State governments should commit to a 10-year agreement to provide stable longterm funding for regional Natural Resource Management (NRM) bodies, including specific funding to monitor long-term trends in natural resource condition.
Enable accountable community governance of land and soil management: To enable farming communities to protect themselves from free-riding, they should be supported to develop stewardship standards based on a shared understanding of what it takes to maintain productive agricultural landscapes over the long term.
Align financial incentives with the long-term needs of sustainable farming communities: In addition to the drought policy reforms announced on October 26, drought assistance policies should support farming communities to take a lead in preparations for more frequent and severe droughts, and should be linked to community stewardship standards.
âRecent projections indicate the potential doubling of exports by 2050, according to the National Food Plan and ANZ-commissioned Greener Pastures report. Our work looks at how to support farmers dealing with the practical challenges of seizing this opportunity, in the context of soil degradation and rising input costsâ, said Laura Eadie.
The case to increase research funding and foster innovative farming is made even stronger by the likely impacts of climate change. Without action to adapt to more variable and extreme weather, by 2050 Australia could lose 6.5 billion per year in wheat, beef, mutton, lamb and dairy production.
The report profiles leading farmers who are already seeing the benefits of innovations in sustainable farming. It proposes simple measures to support them and the agricultural communities that depend on healthy farming landscapes.
Download Farming Smarter, Not Harder report in full
[Australia\u27s newly appointed Advocate for Soil Health, Michael Jeffery, also chairs the non-profit organisation Soils for Life which is already actively encouraging wider adoption of smarter farming. The Soils for Life report Innovations for Regenerative Landscape Management showcases a range of case studies of these farming innovations in practise, and the positive economic, environmental and social outcomes they are achieving. Read the case studies, learn more about the challenges landscape degradation will bring and what we can do about it at www.soilsforlife.org.au.
The Australia we love: a report on key issues affecting nature and society in Australia
This report identifies the need to establish a clear and credible baseline of key trends and issues affecting nature and society in Australia and around the world, on the assumption that a healthy Australian society relies on healthy nature for our prosperity and our wellbeing. This credible baseline is one necessary element for galvanizing and growing a peopleâs movement for nature in Australia. Such a movement will be critical if Australians are to adopt and implement the systemic changes required of our society to achieve our true potential this century.
The report is divided into 7 sections.
Section 1 highlights the importance of healthy nature as the foundation for a healthy and prosperous society.
Section 2 is a brief note of the long history of human influence on nature in Australia, and the complexity involved in decisions regarding land, water and sea.
Section 3 provides a synthesis of some of the key indicators of the pressures on nature in Australia and the impact of these pressures on Australian nature and society. Many of the measures reported here are simply snapshots in time and space, highlighting the difficulty of measuring the complexity of nature and our interactions with it in any comprehensive way.
Section 4 is a synthesis of similar indicators at a global scale.
Section 5 looks at how progress is measured in Australia, and the importance of adopting broader definitions of sustainable wellbeing as a frame for effectively valuing and protecting nature.
Section 6 tells the stories of ordinary Australians doing extraordinary things for nature, inspiring us all to better value and protect what we have.
Section 7 is a call to action that looks ahead to an innovative and solutions-focused future in which Australia is effectively valuing and protecting nature as the foundation for the sustainable wellbeing of our society
The Claiborne Corridor: Mid-Anchor Business Profiles 2014
The New Orleans Business Alliance and the Mayorâs Office of Place-based Planning are working closely with the Livable Claiborne Communities Initiatives to encourage the maintenance, development and expansion of businesses throughout the city with a special focus on the LCC. The reports that follow identify mid-anchor businesses that have contributed to the social and economic wealth of the City of New Orleans for, in some cases, hundreds of years. The hope is that these businesses will be supported through new City initiatives to improve façades, marketability and expand employment opportunities. The research and resources provided by the students at UNO will support these efforts and hopefully contribute to the reinvestment and redevelopment of the new New Orleans
The Claiborne Corridor: Mid-Anchor Business Profiles 2014
The New Orleans Business Alliance and the Mayorâs Office of Place-based Planning are working closely with the Livable Claiborne Communities Initiatives to encourage the maintenance, development and expansion of businesses throughout the city with a special focus on the LCC. The reports that follow identify mid-anchor businesses that have contributed to the social and economic wealth of the City of New Orleans for, in some cases, hundreds of years. The hope is that these businesses will be supported through new City initiatives to improve façades, marketability and expand employment opportunities. The research and resources provided by the students at UNO will support these efforts and hopefully contribute to the reinvestment and redevelopment of the new New Orleans
Electric Revolution and Free Floating Car Sharing: A Data Driven Methodology for System Design
Nowadays, the increase in traffic congestions, land consumption, and pollution emission
due to private car ownership makes the rise of shared mobility possible. One of the
most spread implementations of shared mobility is Free Floating Car Sharing (FFCS). It
is a car rental model where the users can pick and release the car everywhere within an
operative area. The customers can reserve (and return) the vehicle using a web-based
application. With just a simple tap, the users can unlock and lock the smart vehicle.
Usually, the provider bills the users only for the time spend driving, with time-minute
based fares. All the other costs, like petrol, insurance, and maintenance, are in charge
of the provider.
This serviceâs flexibility fills the urban mobility gap between public transportâs relative
cheapness and the comfort and capillarity of private car ownership. Indeed, FFCS
allows people to travel and commute faster than the standard public bus but avoiding
all the fixed and variable costs related to private car ownership.
Given the recent electric cars market increase and all the benefits those vehicles
carry, replacing FFCS fleet with electric-powered cars may still improve urban centersâ
quality of life. The setup and management of an electric FFCS require ingenuity to
minimize the usersâ discomfort due to car plugging procedures.
In my thesis, I present a methodology to address, in different cases of studies, all
the challenges related to the conversion of combustion engine cars to electric vehicles
in FFCS. In particular, my researchâs main driver is to propose a methodology to build
a profitable and technically sustainable system setup, able to guarantee a flexible and
appealing mobility service to an increasing customer audience.
In the first part of my thesis, I describe the software I developed to scrape from the
web real combustion engine FFCS, from two providers: car2go and Enjoy. The car2go
data collection lasted from December 2016 to January 2018, collecting more than 27
million usersâ bookings spread in 23 cities. The Enjoy data collection phase started in
May 2017 and lasted until June 2019, recording about 6 million bookings in 6 cities.
Then, I characterize both datasets in Turin, one of the cities in which both FFCS
providers work. I detect the outliers, filter them out from the dataset, and extract geotemporal
usersâ travel patterns.
After that, I compare the car2go customerâs pattern with the one-way and two-way
car-sharing system. The results show how users prefer more flexible services like FFCS
or one-way car sharing.
Once the data are consolidated, I develop: A methodology to place a charging station
in a city by looking at usersâ patterns. System policies to manage the fleet when
the vehicle state of charge may not guarantee a trip. Via an event-based trace-driven
simulator able to replicate the recorded trips in an electrified scenario evaluating each
configurationâs feasibility.
Via accurate simulation in Berlin, Milan, Turin, and Vancouver, I study different
electric FFCS setup. By placing the charging station in the most frequented areas, by
offering an incentive to the users to plug the car when the battery state of charge is
below a safety threshold, and balancing the spread of poles, it is possible to obtain a
sustainable system covering with charging station only the 8-10 % of zones.
To reduce the number of charging stations to have a sustainable electric FFCS, I
compare several optimization algorithms. The results show how a Genetic Algorithm
can find a better solution to shrink the minimum amount of resources to sustain the
same mobility demand.
After that, I move my attention to the usersâ rentalsâ demand predictability. The
main goal is to understand how different open-data sources could impact the recorded
FFCS usersâ rental. Initially, I compare several time-series forecasts to predict the usersâ
demand in the short and medium-term. Random Forest regression produces better accuracy
and results in terms of interpretability. Then I correlate the socio-economics
features characterizing each city neighborhood to FFCS demand, and again, the Random
Forest regression outperforms other algorithms.
Finally, I question the system scalability figuring out several scenarios having increasing
demand. I use a model to synthesize usersâ demand by looking only at the
geospatial usersâ rentals. By varying the electric FFCS setup and simulating the new
scenario, I point out how a linear increase in the demand intensity requires a fleet sublinear
increase. Finally, I project those considerations in euros, proofing how electric
FFCS has room for economic growth
Overview of Australian Aboriginal and Torres Strait Islander health status 2016
This report provides a comprehensive overview of the most recent indicators of the health and wellbeing of Aboriginal and Torres Strait Islander people. Information focuses on: Aboriginal and Torres Strait Islander populations the context of Aboriginal and Torres Strait Islander health various measures of population health status selected health conditions health risk and protective factors.
The Overview shows that the health of Aboriginal and Torres Strait Islander people continues to improve slowly and there has been a decline in the death rates for Aboriginal and Torres Strait Islander people and also a significant closing of the gap in death rates between Aboriginal and Torres Strait Islander and non-Indigenous people. The infant mortality rate has declined significantly. There have also been improvements in a number of areas contributing to health status such as the proportion of Aboriginal and Torres Strait Islander mothers who smoked during pregnancy has decreased. There has been a slight decrease in the proportion of low birth weight babies born to Aboriginal and Torres Strait Islander mothers between 2004 and 2014. Age-standardised death rates for respiratory disease in NSW, Qld, WA, SA and NT declined by 26% over the period 1998-2012 for Aboriginal and Torres Strait Islander people.
Two new sections are featured in this edition of the Overview. With the 20th anniversary of the Bringing them home report, a section has been dedicated to Healing which highlights the contribution of healing workers and organisations to supporting people, families and communities impacted by the Stolen Generations. Environmental health with its important link to the social determinants of health is also included for the first time in the Overview 2016
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