This study analyzes the feasibility of using algae cultivated from wastewater effluent to produce a biodiesel feedstock. The goal was to determine if the energy produced was greater than the operational energy consumed without consideration to constructing the system as well as the emissions and economic value associated with the process.
Four scenarios were created:
1) high-lipid, dry extraction.
2) high-lipid, wet extraction.
3) low-lipid, dry extraction.
4) low-lipid, wet extraction.
In all cases, the system required more energy than it produced. In high lipid scenarios, the energy produced is close to the energy consumed, and a positive net energy balance may be achieved with minor improvements in technology or accounting for coproducts. In the low lipid scenarios, the energy balance is too negative to be considered feasible. Therefore the lipid content affects the decision to implement algae cultivation.
The dry extraction and the wet extraction both require some level of mechanical drying and this makes the two methods yield similar results in terms of the energy analysis. Therefore, the extraction method does not dramatically affect the decision for implementing algae-based oil production from an energetic standpoint. The economic value of the oil in both high lipid scenarios results in a net profit despite the negative net energy. Emission calculations resulted in avoiding a significant amount of CO2 for high lipid scenarios but not for the low lipid scenarios. The CO2 avoided does not account for non-lipid biomass, so this number is an underestimation of the final CO2 avoided from the end products.
While the term "CO2 avoided" has been used for this study, it should be noted that this CO2 would be emitted upon use as a fuel source. These emissions, however, are not “new” CO2 because it has already been emitted and is being captured and recycled. Currently, literature is very divisive on the lipid content present in algae and this study shows that lipid content has a tremendous affect on energy and emissions impacts. The type of algae that can grow in wastewater effluent also should be investigated as well as the conditions that promote high lipid accumulation. The dewatering phase must be improved as it is extremely energy intensive and dominates the operational energy balance.
In order to compete, wet extraction must have a much more significant effect on the drying phase and must avoid the use of the human toxicants methanol and chloroform. Additionally, while the construction phase was beyond the scope of this project it may be a critical aspect in determining the feasibility these systems. Future research in this field should focus on lipid production, optimizing the belt dryer or finding a different method of dewatering, and allocating the coproducts.
The research topic for this assignment is shrimp farming in Thailand located throughout the coastal areas of the southern, eastern, and central regions of the country. Thailand’s huge shrimp export driven industry represents one of the largest in the world accounting for over twenty-five percent of food exports out of the country (Sriboonchitta & Wiboonpongse, n.d.).
Specific research questions include:
1. What are the current unsustainable practices in shrimp farm production?
2. In what part of the life cycle should intervention take place?
3. What does a sustainable shrimp farming practice look like in the future?
Anticipatory LCA seeks to overcome the paucity of data through scenario development and thermodynamic bounding analyses. Critical components of anticipatory LCA include:
1) Laboratory-scale inventory data collection for nano-manufacturing processes and
preliminary performance evaluation.
2) Thermodynamic modeling of manufacturing processes and developing scenarios of
efficiency gains informed by analogous material processing industries.
3) Use-phase bounding to report inventory data in a functional unit descriptive of
performance.
Together, these analyses may call attention to environmentally problematic processes or nanotechnologies before significant investments in R&D and infrastructure contribute to technology lock in. The following case study applies these components of anticipatory LCA to single wall carbon nanotube (SWCNT) manufacturing processes, compares the rapid improvements in SWCNT manufacturing to historic reductions in the embodied energy of aluminum, and discusses the use of SWCNTs as free-standing anodes in advanced lithium ion batteries.
Sonoma County, CA is on an ambitious pathway to meeting stringent carbon emissions goals that are part of California Assembly Bill 32. At the county-level, climate planners are currently evaluating options to assist residents of the county in reducing their carbon footprint and also for saving money. The Sonoma County Energy Independence Program (SCEIP) is one such county-level measure that is currently underway. SCEIP is a revolving loan fund that eligible residents may utilize to install distributed solar energy on their property. The fund operates like a property tax assessment, except that it only remains for a period of 20 years rather than in perpetuity.
This analysis intends to estimate the potential countywide effect that the $100M SCEIP fund might achieve on the C02 and cost footprint for the residential building energy sector. A functional unit of one typical home in the county is selected for a 25 year analysis period. Outside source data for the lifecycle emissions generated by the production, installation and operations of a PV system are utilized. Recent home energy survey data for the region is also utilized to predict a “typical” system size and profile that might be funded by the SCEIP program. A marginal cost-benefit calculation is employed to determine what size solar system a typical resident might purchase, which drives the life cycle assessment of the functional unit. Next, the total number of homes that might be financed by the SCEIP bond is determined in order to forecast the potential totalized effect on the County’s lifecycle emissions and cost profile.
The final results are evaluated and it is determined that the analysis is likely conservative in its estimation of the effects of the SCEIP program. This is due to the fact that currently offered subsidies are not utilized in the marginal benefit calculation for the solar system but do exist, the efficiency of solar technology is increasing, and the cost of a system over its lifecycle is currently decreasing. The final results show that financing distributed solar energy systems using Sonoma County money is a viable option for helping to meet state mandated goals and should be further pursued.
Our objectives are to:
1. Review the LCA literature to determine the dominant environmental impact categories in
wild-caught fisheries in order to evaluate which phases are causing the greatest impacts.
2. Determine how these impacts can best be mitigated and develop a framework that seeks
to incorporates LCA into sustainable seafood guides so that consumers can make better-
informed decisions.
This framework will include developing meaningful LCA impact categories for sustainable seafood guides. Despite their importance, we considered social factors beyond the scope of this paper.
Our study calculates the estimated difference in water use, energy demands, and CO2 emissions of head lettuce associated with the production (land preparation and growing operations, chemical inputs, irrigation) and the transportation (diesel demand) to the Phoenix metro area from:
1. A local level, defined here as within Maricopa County, Arizona (AZ).
2. From the central coast of California (CA) in Monterey County.
Our research results demonstrate that local lettuce is more resource intensive than non-local or regional produce. Production in Maricopa County has significantly higher (more than double) energy demands and emissions than Monterey County. Irrigation and chemical inputs are the greatest contributors to energy demand in Maricopa, but it is primarily irrigation that contributes to emissions. Comparatively, transportation and chemical inputs are the greatest contributors to energy demand in Monterey, and it is primarily transportation that contributes to emissions.
This life cycle inventory suggests that we need to reconsider the “food miles” framing of the local food debate and whether local food production is a viable sustainable alternative to the current food system in the arid Southwest. However, we also recognize that factors beyond resource-use and emissions affect policymakers’ and consumers’ demands for local foods. Future studies ought to provide a more nuanced look at the issue that also includes social, psychological, and economic factors that influence food policies and purchases. These results have important implications for future water management and suggest the need to pursue more water efficient practices in AZ.
the US comparing parental perception of their child’s diet with quantitatively assessed diet quality. We examined the association between parent perception of their child’s overall diet and the child’s diet quality, as measured by frequency of consumption of key food categories.
Methods: Secondary analysis was conducted using data from two independent cross- sectional panels of surveys with parents of a 3-18 year old child. Data collection took place in 2009-2010 and 2014, the random sample was drawn from low-income cities. Well-established survey questions assessed parental perception of their child’s diet and frequency of consumption of fruits, vegetables, sugar-sweetened beverages (SSB), fast food and unhealthy snacks. Diet quality scores were calculated for each child, with higher scores reflective of healthier diets (max score= 40). Ordered logistic regressions examined associations between parental perception and consumption of food categories. Multinomial logistic regressions examined associations between levels of concordance in parent perception and diet scores by demographic sub-groups.
Results: Almost half of children were non-Hispanic black (46%) and 40% were Hispanic. Overall 52% of parents strongly agreed, 33% somewhat agreed, 10% somewhat disagreed, and 4% strongly disagreed that their child eats a healthy diet. The mean diet quality score for the sample was 20.58 ± 6.7. Children from our sample with the unhealthiest diet had a mean frequency of fruit intake = 0.8 times/day and SSBs = 2.2 times/day. Children with the healthiest diet had a mean consumption of fruit=1.7/day and
SSBs= 0.4/day. Parental perception of their child’s diet was significantly higher when their child consumed more fruit (p<0.001) and vegetables (p<0.001) and lower when their child consumed more fast food (p<0.001), SSBs (p=0.01) and unhealthy snacks (p=0.02). Over half of parents overestimated the healthfulness of their child’s diet (61%). Parent, child and household demographics did not moderate this association.
Conclusions: Although parental perceptions that their child eats healthy are associated when their child eats more healthy foods and less unhealthy foods, parents’ perceptions still do not align with their child’s diet.
Methods: Data were obtained from two cross-sectional panels (2009-10 and 2014) of the New Jersey Child Health Study conducted in four low-income New Jersey cities. Questions from previously validated surveys assessed consumption frequency of fruits, vegetables, SSBs, and sweet and salty snacks. Analyses were confined to 570 children between 5-18 yrs; of which 365 (5-11 yrs: 237, 12-18 yrs: 128) resided in WIC participating households and 205 (5-11 yrs: 138, 12-18 yrs: 67) in income-qualifying non-WIC households. Over half of the sample was African American and 43% were Hispanic. Multivariable analyses were conducted to compute incidence rate ratios (IRRs) using negative binomial regression to compare the differences in eating behaviors of children in WIC vs. Non-WIC households
Results: Household WIC participation was associated with a slightly higher frequency of vegetable consumption among 12-18-year-old children (IRR= 1.25, p=.05); differences were significant among older males (12-18-years-old) (p=.006), and not in females.
Frequency of 100% juice consumption was significantly higher among younger females (5-11-years-old) in WIC households who consumed juice about 44% more frequently (p=.02) compared to similar age girls in non-WIC households. Hispanic children in WIC households reported a lower frequency of SSBs consumption (p=.01); this association was only true among males (p=.02).
Conclusions: Household WIC participation is associated with healthier dietary behaviors among age-ineligible children living in the households, suggesting a positive spillover effect of the program. Proposed changes to WIC packages are likely to have dietary implications not only for WIC participants but also for non-participating children residing in WIC households,