Direct Load Control Demand Response Program for Air Conditioners

According to importance of demand response programs in last decades, many efforts have been made to change the consumption patterns of the users, and the use of renewable resources has also increased. Significant part of energy consumption belongs to the entire kinds of the buildings such as residential, commercial, and office buildings. In this context, the air conditioners can play an important role in demand response programs. Air conditioners can be as thermostatically controllable appliances for direct load control demand response program. In this paper, an optimization algorithm is developed to optimize the power consumption of air conditioners based on the user preferences to maintain the user comfort. The methodology of this work is proposed as a linear optimization problem that consider the generation of a renewable energy resource, which supplies a part of the energy consumption of the building. For the case study, the amount of the renewable energy generation, total consumption of building, and the consumption of the air conditioners in a real research building are considered and the optimization has been done based on the realistic data.This work has received funding from the European Union's Horizon 2020 research and innovation program under the Marie Sklodowska-Curie grant agreement No 641794 (project DREAMGO) and from FEDER Funds through COMPETE program and from National Funds through FCT, under the project UID/EEA/00760/2013.info:eu-repo/semantics/publishedVersio

Optimal Building Thermal Load Scheduling for Simultaneous Participation in Energy and Frequency Regulation Markets

This paper presents an optimal scheduling solution for building thermal loads that simultaneously participate in the wholesale energy and frequency regulation markets. The solution combines (1) a lower-level regulation capacity reset strategy that identifies the available regulation capacity for each hour, and (2) an upper-level zone temperature scheduling algorithm to find the optimal load trajectory with a minimum net electricity cost. In the supervisory scheduling strategy, piece-wise linear approximations of representative air-conditioning equipment behaviors, derived from an offline analysis of the capacity reset mechanism, are used to predict the cooling power and regulation capacity; and a mixed-integer convex program is formulated and solved to determine the optimal control actions. In order to evaluate the performance of the developed control solution, two baseline strategies are considered, one with a conventional night setup/back control and the other utilizing an optimization procedure for minimizing the energy cost only. Five-day simulation tests were carried out for the various control strategies. Compared to the baseline night setup/back strategy, the energy-priority controller led to a 26% lower regulation credit and consequentially caused a net cost increase of 2%; the proposed bi-market control solution was able to increase the regulation credit by 118% and reduce the net electricity cost by 14%.Open Access fees paid for in whole or in part by the University of Oklahoma Libraries.Ye

Life Cycle & Technoeconomic Modeling

This book aims to perform an impartial analysis to evaluate the implications of the environmental costs and impacts of a wide range of technologies and energy strategies. This information is intended to be used to support decision-making by groups, including researchers, industry, regulators, and policy-makers. Life cycle assessment (LCA) and technoeconomic analysis can be applied to a wide variety of technologies and energy strategies, both established and emerging. LCA is a method used to evaluate the possible environmental impacts of a product, material, process, or activity. It assesses the environmental impact throughout the life cycle of a system, from the acquisition of materials to the manufacture, use, and final disposal of a product. Technoeconomic analysis refers to cost evaluations, including production cost and life cycle cost. Often, in order to carry out technoeconomic analysis, researchers are required to obtain data on the performance of new technologies that operate on a very small scale in order to subsequently design configurations on a commercial scale and estimate the costs of such expansions. The results of the developed models help identify possible market applications and provide an estimate of long-term impacts. These methods, together with other forms of decision analysis, are very useful in the development and improvement of energy objectives, since they will serve to compare different decisions, evaluating their political and economic feasibility and providing guidance on potential financial and technological risks

Application of heat pumps and thermal storage systems for improved control and performance of microgrids

The high penetration of renewable energy sources (RES), in particular, the rooftop photovoltaic (PV) systems in power systems, causes rapid ramps in power generation to supply load during peak-load periods. Residential and commercial buildings have considerable potential for providing load exibility by exploiting energy-e_cient devices like ground source heat pump (GSHP). The proper integration of PV systems with the GSHP could reduce power demand from demand-side. This research provides a practical attempt to integrate PV systems and GSHPs e_ectively into buildings and the grid. The multi-directional approach in this work requires an optimal control strategy to reduce energy cost and provide an opportunity for power trade-o_ or feed-in in the electricity market. In this study, some optimal control models are developed to overcome both the operational and technical constraints of demand-side management (DSM) and for optimum integration of RES. This research focuses on the development of an optimal real-time thermal energy management system for smart homes to respond to DR for peak-load shifting. The intention is to manage the operation of a GSHP to produce the desired amount of thermal energy by controlling the volume and temperature of the stored water in the thermal energy storage (TES) while optimising the operation of the heat distributors to control indoor temperature. This thesis proposes a new framework for optimal sizing design and real-time operation of energy storage systems in a residential building equipped with a PV system, heat pump (HP), and thermal and electrical energy storage systems. The results of this research demonstrate to rooftop PV system owners that investment in combined TSS and battery can be more profitable as this system can minimise life cycle costs. This thesis also presents an analysis of the potential impact of residential HP systems into reserve capacity market. This research presents a business aggregate model for controlling residential HPs (RHPs) of a group of houses that energy aggregators can utilise to earn capacity credits. A control strategy is proposed based on a dynamic aggregate RHPs coupled with TES model and predicting trading intervals capacity requirements through forecasting demand and non-scheduled generation. RHPs coupled with TES are optimised to provide DSM reserve capacity. A rebound effect reduction method is proposed that reduces the peak rebound RHPs power

Energy reduction in tertiary education buildings: establishing functional area energy consumption benchmarks using the LLO tool

This research establishes comprehensive and improved energy consumption benchmarks for Australian tertiary education facilities. It examines the audit of energy end use in various functional areas in a sample of tertiary education institutions to identify, control and reduce electrical energy used in typical existing campus buildings. Many Australian universities have data available for energy consumption of their total campus and selected individual whole buildings. However, as the typical tertiary campus is characterised by a large and diversified portfolio of buildings with differing architecture, facades, occupancy and services, energy comparison between buildings does not provide useful information. This differs from energy use and management in general commercial office buildings. Universities also have different disciplines performing different activities that are not directly comparable. For instance, a campus with a medical school or molecular science building (service equipment intensive type) has a different energy use profile from one that does not. This research develops a common tertiary education functional typology within different campus buildings, grouped according to significant architectural features, energy intensity and use, to establish appropriate energy benchmarks for common functional areas such as offices, lecture rooms and laboratories. Assessment of these common functional areas by energy audit allows quantitative comparison between functional areas, and between diverse whole buildings. It also provides a rational basis for establishing performance targets for buildings at the early design stage by aggregation of functional areas. Benchmarking these areas allows energy managers to manage by exception and the benchmarking process enables managers to practise continuous improvement. The knowledge and data from this study enables researchers to focus on those factors that specifically affect energy use for particular activities. This enables building energy managers to discern and rank those major factors that determine energy consumption, allowing them to concentrate their performance efforts on the most energy efficient measures. The benchmarks derived in this study came from audits of 24 buildings at the University of Sydney campus across a five-year period (2009–2014) comprising over 80 distinct functional areas. Using this data, together with local and overseas sources, the LLO functional area energy benchmark tool was developed. LLO is an acronym derived from the surnames of the researcher and two colleagues who discussed the development of the University of Sydney graduate energy audit program in 2009

Aerobic biodegradation of per-treated methyl tert-butyl ether by ozonation in an up-flow-fixed-bed reactor

Problem Statement: MTBE is a common pollution of environmental and has become an issue of considerable concern in recent years. It is not readily amenable to remove MTBE by conventional techniques in water treatment. In the present study, the feasibility of the continuous aerobic biodegradation of MTBE, was evaluated in an Up- Flow Fixed Bed Reactor (UFBR). Approach: The UFBR at a constant Hydroulic Retention Time (HRT) of 24 h was used as a biological process that receives the intermediates due to partial oxidation of MTBE. The UFBR coupled to ozonation process as a survey system after a primary operation phase that was necessary for creatory of an initial microbial film on the carriers. Residual concentration of MTBE and its major degradation intermediates were measured by gas chromatography. Aqueous concentration of ozone in the reactor and ozone average concentration in off- gas were determined according to the indigo blue method. The COD reduction and BOD5 to COD ratio were selected as biodegradability indexes. Results: Results showed an effective degradation of MTBE in the coupled ozonation-UFBR continuous flow reactor of ten days of operation time. A partial degradation of MTBE in AOPs increases its biodegradation The BOD5 to COD ratio increased from lowest (0.01) up to a maximum of 0.72 that corresponds to an ozone consumption of 0.62mg per each mg of COD initially present in the solution. The results showed when m. MolMTBEo/m. Mol(o3) = 0.611, the COD removal efficiency was 89% and as this ratio increased up to 1.25, the of COD removal efficiency decreased to 80%. 46-68% removal of the COD was needed before the mixture was considered biodegradable. The highest removal rate of MTBE, 82.91 mg day-l achieved through out the UFBR runs (87% removal efficiency, In this study, the removal efficiency of MTBE using integrated-process (ozonation followed biological treatment) was from 78.5-86.5%. In order to determine of biological removal rate of MTBE, another UFBR system used as a blank reactors. Results showed that the efficiency of the COD removal (by stripping with the biological degradation) was 5-8% which implies insignificant biological removal of MTBE without pre-ozonation. Solid produced in the proposed integrated process was 0.27-0.35 kg TSS kg-1 COD removed which is approximately in down range of conventional biological system (0.3-0.5 kg TSS kg-1COD). Conclusion: Present study showed that we can treatment of the polluted aqueous solutions to MTBE without microbial incubation used to integrated process. © 2009 Science Publications