Evaluating microgrid effectiveness in transitioning energy portfolios

Microgrid energy systems have emerged as a potential solution to rising greenhouse gas emissions from dependence on fossil fuels. This research provides a framework for evaluating the utility of microgrids. Three key findings are presented: use of a state-of-the-art matrix (SAM) analysis to identify gaps in key research areas that inhibit wide-spread microgrid adoption, development of a system dynamics (SD) model, and a cost benefit analysis case study to evaluate microgrid feasibility in partially meeting the energy demand of a building. Governments play a central role in developing clean energy strategies. A SAM was developed to determine if key microgrid barriers to adoption defined by a state government were being addressed. The results of the study suggest that environmental and sustainability benefits had not been sufficiently addressed. Using the SAM findings, an SD model was used to evaluate the environmental and sustainability benefits of transitioning a state\u27s residential electricity portfolio. The SD model outputs suggest that fossil fuel depletion and greenhouse gas emissions would be reduced, but the financial investment would be significant. Lastly, a cost benefit analysis was conducted on a microgrid partially meeting the energy demand of a university campus building. The results demonstrated that selection of a proper discount factor and recognition of useful life are critical success factors for microgrid energy projects. Collectively, these findings provide the engineering manager with a method to evaluate the feasibility of proposed microgrid projects, the city planner with the system-level implications of a large-scale energy transition project, and the policy maker with the necessary information to develop policies that promote a clean energy future --Abstract, page iv

Infrastructure systems modeling using data visualization and trend extraction

“Current infrastructure systems modeling literature lacks frameworks that integrate data visualization and trend extraction needed for complex systems decision making and planning. Critical infrastructures such as transportation and energy systems contain interdependencies that cannot be properly characterized without considering data visualization and trend extraction. This dissertation presents two case analyses to showcase the effectiveness and improvements that can be made using these techniques. Case one examines flood management and mitigation of disruption impacts using geospatial characteristics as part of data visualization. Case two incorporates trend analysis and sustainability assessment into energy portfolio transitions. Four distinct contributions are made in this work and divided equally across the two cases. The first contribution identifies trends and flood characteristics that must be included as part of model development. The second contribution uses trend extraction to create a traffic management data visualization system based on the flood influencing factors identified. The third contribution creates a data visualization framework for energy portfolio analysis using a genetic algorithm and fuzzy logic. The fourth contribution develops a sustainability assessment model using trend extraction and time series forecasting of state-level electricity generation in a proposed transition setting. The data visualization and trend extraction tools developed and validated in this research will improve strategic infrastructure planning effectiveness”--Abstract, page iv

A Time Series Sustainability Assessment of a Partial Energy Portfolio Transition

Energy portfolios are overwhelmingly dependent on fossil fuel resources that perpetuate the consequences associated with climate change. Therefore, it is imperative to transition to more renewable alternatives to limit further harm to the environment. This study presents a univariate time series prediction model that evaluates sustainability outcomes of partial energy transitions. Future electricity generation at the state-level is predicted using exponential smoothing and autoregressive integrated moving average (ARIMA). The best prediction results are then used as an input for a sustainability assessment of a proposed transition by calculating carbon, water, land, and cost footprints. Missouri, USA was selected as a model testbed due to its dependence on coal. Of the time series methods, ARIMA exhibited the best performance and was used to predict annual electricity generation over a 10-year period. The proposed transition consisted of a one-percent annual decrease of coal’s portfolio share to be replaced with an equal share of solar and wind supply. The sustainability outcomes of the transition demonstrate decreases in carbon and water footprints but increases in land and cost footprints. Decision makers can use the results presented here to better inform strategic provisioning of critical resources in the context of proposed energy transitions

Deceleration of droplets that glide along the free surface of a bath

A droplet obliquely impacting a bath surface of the same fluid can traverse along the interface while slowing at an exponential rate. The droplet rests on a thin film of air and deforms the bath surface creating a dimple and travels along the surface similar to a wave pulse. Viscous coupling of the droplet and bath surfaces through the air film leads to viscous drag on the bath and perturbs the wave motion of the otherwise free surface. Even though Reynolds numbers are greater than unity (Re O(10 -- 100)), we show that the droplet\u27s deceleration is only due to viscous coupling through the air gap. The rate of deceleration is found to increase linearly with droplet diameter

Droplet Impact, Part 1: Controlling Skirting Velocity

Droplet skirting occurs when a fluid droplet rolls over a bath of the same fluid without merging. To achieve skirting, we introduced a ~0.6 mm-diameter droplet of 1 cSt silicone oil into a bath of the same fluid by bouncing it off an angled glass slide coated with 100,000 cSt silicone oil. Our work suggests that initial skirting velocity increases as a function of slide angle and, to a lesser degree, droplet generator height. Furthermore, we conclude that the droplet lifetimes (initiation of skirting until rupture) and corresponding values (rate of decay of motion) appear consistent with theoretical predictions for such droplets based on previous research (which did not address \u3e0.75 mm-diameter droplets

Droplet Impact, Part 2: Engineering a Droplet Generator

Prior droplet impact research at DePauw used a syringe to pump fluid through a tube to create a droplet. This method generated ~2.5mm diameter droplets with secondary satellite droplets that formed during pinch-off and influenced rupture upon collision with the main droplet. Furthermore, the large diameter caused the droplet to experience significant oscillation as it fell, making it difficult to control impact shape without changing impact velocity. Part of this summer’s research focused on adapting preexisting designs for droplet generators to build our own version that creates small, consistent droplets without interference from satellite droplets or jets (which form at high speeds/large diameters)

Flood Management Deep Learning Model Inputs: A Review of Necessary Data and Predictive Tools

Current flood management models are often hampered by the lack of robust predictive analytics, as well as incomplete datasets for river basins prone to heavy flooding. This research uses a State-of-the-Art matrix (SAM) analysis and integrative literature review to categorize existing models by method and scope, then determines opportunities for integrating deep learning techniques to expand predictive capability. Trends in the SAM analysis are then used to determine geospatial characteristics of the region that can contribute to flash flood scenarios, as well as develop inputs for future modeling efforts. Preliminary progress on the selection of one urban and one rural test site are presented subject to available data and input from key stakeholders. The transportation safety or disaster planner can use these results to begin integrating deep learning methods in their planning strategies based on region-specific geospatial data and information

Improving the efficiency of material flows in an Independent Timber & Builders’ Merchants Business via the implementation of a new dedicated Goods Inward/Outward facility featuring Cross-Dock methodology

This study looks at the physical logistics challenges facing the Independent Builders’ Merchants sector within the Construction Industry Supply Chain. Against a backdrop of economic uncertainty, industry commentators have recently observed that the sector has previously accepted mediocrity in logistics because it has not understood how it can add value. The facet of on-site material flows at an exemplar Independent Builders Merchant is therefore taken as the research question to investigate whether current generic logistics techniques can be used to improve efficiency in this field. ‘Cross-docking’ is one such logistics technique which has been introduced in recent times in an attempt to move materials from inbound locations to outbound locations as quickly as possible. This short-term staging approach can be used to consolidate shipments from disparate sources and realise economies of scale in outbound transportation. In this research, system adherence, layout design and short term staging strategy are investigated to ascertain their applicability to addressing the losses in terms of time, transport costs, damage and, above all, customer satisfaction resulting from the lack of a fully formalised inbound supply chain process. Keywords: Construction Supply Chain, Builders’ Merchants, Physical Logistics, Material Flows, Cross-Dock, Goods Inward, Goods Outwar