Electric Load Management Research Articles

Simulation-based assessment of electric load management programs

The paper describes a methodology for assessing the contribution of storage type loads to an electric energy system's load curve and for evaluating the impact of load shedding actions, as part of load management programs, on the system's load curve. The methodology uses physically based individual load models and an aggregation procedure that accounts for both statistical reference patterns of the energy service demand and for the random nature of load use. A simulation case study of electric water heaters fed by a single transformer station is presented, to illustrate the effects of load control. The proposed methodology presents the possibility of evaluating-both at individual consumer level and at system level-the impacts of load management (LM) on the quality of service provided, besides anticipating the impact on the system's load curve. It allows an effective design of LM programs through variables such as the number of different load shedding schedules and their frequency of use by the utility.

Thermal performance of a latent heat energy storage ventilated panel for electric load management

A theoretical study was conducted to assess the thermal performance of a ventilated panel heating unit. The unit employs the latent heat energy storage method to level the electrical energy demand for domestic space heating during peak hours. A one-dimensional, semi-empirical model was developed to predict the dynamic thermal behavior of the storage unit under cyclic melting and solidification. The results show that the storage unit may be charged and discharged more than twice a day with a charge time shorter than the discharge time. The temperature of the plate in contact with the ambient air may be controlled to reach higher values without compromising the unit heating power. General correlations of the charge and discharge times are established for a wide range of the governing parameters.

Review on sustainable thermal energy storage technologies, Part II: cool thermal storage

This paper describes the inherent pros and cons of the two common (i.e. chilled water and ice storage) commercially available thermal energy storage (TES) technologies for off-peak air conditioning applications. Case studies on cool thermal storage have demonstrated not only savings in energy and other operation and maintenance costs but also significant savings in initial capital costs. This paper also examines the use of cool thermal storage equipment for gas turbine inlet air cooling, which can positively enhance its efficiency. It has been observed that the application of TES has been predominantly in North America. However, in the mid-1990 s, applications have begun to appear in Asia, Australia, Europe and South America. Finally, prospects of TES technologies for electric load management in Saudi Arabia are also elucidated.

Cost minimization for a local utility through CHP, heat storage and load management

The energy-system optimization model MODEST is described, especially heat storage and electricity load management. Linear programming is used for minimization of capital and operation costs. MODEST may be used to find the optimal investments and when to make them. The period under study can be divided into several linked subperiods which may consist of an arbitrary number of years. MODEST is here applied to a municipal electricity and district-heating system during three five-year periods. Each year is divided into three seasons. Demand peaks, as well as weekly and diurnal variations of, for example, costs are considered. The electricity demand is divided into the three sectors households, industries, and service. The electricity demand may be reduced by energy conservation, replacement of electric heating and load management. The profitability of load management, as well as cogeneration with and without heat storage at different prices of purchased power is calculated. At traditional Swedish electricity prices, the local utility should build a woodchips-fired steam-cycle CHP (combined heat and power) plant. Consumers would find it beneficial to reduce their electricity use by conservation and switching from electric heating to oil and biofuel. If just marginal power production costs are paid, the utility should introduce biomass-fired heat-only boilers instead. Electricity conservation is smaller at these lower prices. Load management is mainly profitable at the first price scheme which includes output-power-related charges. The heat storage should be used threefold: to cover demand peaks, as well as to enable increased CHP output when it is limited by the heat demand or to run heat pumps at cheap night electricity instead of in the daytime. © 1998 John Wiley & Sons, Ltd.

Cost minimization for a local utility through CHP, heat storage and load management

The energy-system optimization model MODEST is described, especially heat storage and electricity load management. Linear programming is used for minimization of capital and operation costs. MODEST may be used to find the optimal investments and when to make them. The period under study can be divided into several linked subperiods which may consist of an arbitrary number of years. MODEST is here applied to a municipal electricity and district-heating system during three five-year periods. Each year is divided into three seasons. Demand peaks, as well as weekly and diurnal variations of, for example, costs are considered. The electricity demand is divided into the three sectors households, industries, and service. The electricity demand may be reduced by energy conservation, replacement of electric heating and load management. The profitability of load management, as well as cogeneration with and without heat storage at different prices of purchased power is calculated. At traditional Swedish electricity prices, the local utility should build a woodchips-fired steam-cycle CHP (combined heat and power) plant. Consumers would find it beneficial to reduce their electricity use by conservation and switching from electric heating to oil and biofuel. If just marginal power production costs are paid, the utility should introduce biomass-fired heat-only boilers instead. Electricity conservation is smaller at these lower prices. Load management is mainly profitable at the first price scheme which includes output-power-related charges. The heat storage should be used threefold: to cover demand peaks, as well as to enable increased CHP output when it is limited by the heat demand or to run heat pumps at cheap night electricity instead of in the daytime. © 1998 John Wiley & Sons, Ltd.

Judgmental and statistical methods of peak electric load management

This paper presents the results of a study comparing two computerized peak-shaving systems for an electricity distributing utility company. A judgmentally-based system was designed to replicate an actual human expert in the field, while a statistically-based system was developed to incorporate statistically-based decision rules to replace some of the purely judgmental rules of the expert. These peak management systems were tested against each other, and then tested against the human expert for periods in which data on his actual decisions were available. The results show that when the objective is to correctly predict peaks, and the number of false alarms is not important, the human expert should be used. Alternatively, when the objective is to reduce system nervousness by limiting the number of false alarms, the statistically-based peak management system should be used.

Electricity Pricing and Load Management for Maharashtra

Electricity consumption in India is increasing rapidly. The increased demand forces the electricity boards to increase their generating capacity. The huge investments in generation, transmission, and distribution (at the cost of alternative development projects) adversely affect India's foreign exchange reserves. Also, internal resources like coal are utilized at great risk to the environment This article tries to shift the focus from supply augmentation to demand management by analyzing the existing pricing policy mechanism and suggests different tariffs based on long-rang marginal costs. It is shown that the “economic pricing” based on long-run marginal costs is an indicator of efficient utilization of resources.

System development — the challenges of re-useability

This paper describes the challenges faced by aerospace avionic systems developers in the 1990s, as they use ‘in anger’ both best-practice processes and state-of-the-art tools to try and achieve that most elusive goal in a large system development: Re-useable designs, meeting all customer needs, on-time, and within budget. The Boeing 777 electrical load management system (ELMS) developed by Smiths Industries Civil Systems, Cheltenham, has involved up to 250 engineers since 1991. It is an example of military technology being applied in the civil sector, and integrates over 50 aircraft utility systems as well as managing the supply of electrical power. The author has been Engineering Manager for this system since its inception, and takes this project as an example of large system development. He shares the advantages of those process approaches and types of tool which worked, and the disadvantages of those approaches which were less successful. The objectives of this paper are: • ⊗ To share practical experience of current methods and types of tool for requirements capture, structured analysis, object-oriented design (which is very different to methodologies used only a decade ago), verification/validation and certification. • ⊗ To discuss where these modern methods and tools assist reuseability, and where they impede it. • ⊗ To describe the fresh management challenges they present, such as lack of visibility (-it's all in the system, if you know how to access it!). • ⊗ To examine the design review strategies which and most value with these methods. (More peer-level reviews; less large formal meetings.) • ⊗ To review how well these modern methods cope when faced with customer specification changes — both small changes and large-scale changes. (Is there much value in huge volumes of traceability information if it is all to be scrapped by a large change?) The paper also emphasizes the human elements in a successful development. Examples are the value of co-locating good engineers with customers (and good customer engineers within the developer's teams) and how this compares with technology such as datalinks, conference calls and videoconferencing; the values of concurrent engineering within the project; and good communication at all levels (technical and managerial). The author believes that even with best-class processes and tools, you still need good engineers to have a successful outcome!

Small SMES technology and cost reduction estimates

Superconducting magnetic energy storage (SMES) has been under development for electric system applications for some time. Large units (/spl ges/10 MWh) have been designed for electric load management. Small systems (<10 MW) have been designed for power quality enhancements. Small systems, in particular, can provide momentary carryover on a distribution network, thus avoiding outages in customers' electric supply. The price of today's small units is relatively expensive. The objective of this study was to evaluate possible cost reductions of small SMES devices to determine long-term feasibility for use in utility systems.< <ETX xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">&gt;</ETX>

Solid-state power controller for the next generation

The design philosophies of an electrical load management center (ELMC) for military platforms and the advantages and features made possible only through the use of real-time solid-state power controllers (SSPCs) are discussed. Computer control of power distribution systems will be required to off-load crews and increase system reliability, with improved fault handling, while also protecting the wire and load. The electrical, mechanical, and special competitive features of the SSPC series, the military screening and mechanical specifications, and other product options are highlighted.< <ETX xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">&gt;</ETX>

A residential energy management test using CEBus

A test project undertaken for the testing of evaluation of commercial home automation systems and technologies for applicability to residential energy management is discussed. The project consisted of a cooperative program between an electric utility, several major homebuilders, and various appliance manufacturers. Performance and reliability experiments were conducted in residential environments using the proposed CEBus (consumer electronics bus) standard on powerline. Also, an electrical load management system was constructed and tested.< <ETX xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">&gt;</ETX>

A Comparison of Hybrid Heating Systems and New Generation Facilities for Peak Electricity Load Management

This paper presents a preliminary evaluation of hybrid heating systems as an electric load-management tool for Canadian utilities, based on an analysis of data for the Province of New Brunswick. In comparison to all-electric systems, the study indicates that hybrid heating systems offer many advantages: they are less costly when peak electricity generation is provided by combustion turbines; they can eliminate the need for new peak generating capacity within the 15 year planning horizon of the utility; the higher energy conversion efficiency of hybrid systems reduces oil consumption, and C02 and SOx emissions; and they can be produced, installed and maintained locally, unlike the major components of power plants and many of their installation and maintenance services, which are imported. The constraints upon implementation of the technology are also discussed. A demand management leasing scheme, in which the utility leases the hybrid heating technology from the customer, is described. It offers political and public relations advantages over more traditional cost allocation schemes and ensures the long-term availability of the technology.

Interring the Great Myth: The Ethics of ENERGY EFFICIENCY

Design Management Journal (Former Series)Volume 2, Issue 4 p. 81-84 Interring the Great Myth: The Ethics of ENERGY EFFICIENCY Terence P. Falvey, Terence P. Falvey Terence P. Falvey, P.E., C.C.P., C.E.M., is a consulting engineer whose practice addresses the management and efficient use of large thermal and electrical energy loads. His projects span the range from Energy Audits to Cogeneration Feasibility Studies for a diverse client mix.Search for more papers by this author Terence P. Falvey, Terence P. Falvey Terence P. Falvey, P.E., C.C.P., C.E.M., is a consulting engineer whose practice addresses the management and efficient use of large thermal and electrical energy loads. His projects span the range from Energy Audits to Cogeneration Feasibility Studies for a diverse client mix.Search for more papers by this author First published: Fall 1991 https://doi.org/10.1111/j.1948-7169.1991.tb00094.x AboutPDF ToolsRequest permissionExport citationAdd to favoritesTrack citation ShareShare Give accessShare full text accessShare full-text accessPlease review our Terms and Conditions of Use and check box below to share full-text version of article.I have read and accept the Wiley Online Library Terms and Conditions of UseShareable LinkUse the link below to share a full-text version of this article with your friends and colleagues. Learn more.Copy URL Share a linkShare onFacebookTwitterLinkedInRedditWechat Volume2, Issue4Fall 1991Pages 81-84 RelatedInformation

Electric load management in developing countries

Energy planners in developing countries have traditionally sought to meet their nations' growing electricity demands by adding more generation and transmission capacity. But as the foreign investment situation became critical in the 1980s, private investment and system efficiency improvement programmes began to garner interest. One of the most promising system efficiency improvement options is load management, which uses a variety of techniques to utilize the electricity system's existing capacity more efficiently. However, to date, only three countries have seriously considered implementing large load management programmes: Pakistan, Peru and Costa Rica. This paper describes a 1987‐89 load control demonstration programme in Costa Rica, sponsored by the US Agency for International Development (AID), in which participating industries were able to reduce their peak demand by 14%.

The potential and strategies for demand-side management within the industrial sector in Jordan—I

The potential of electricity load management within the industrial sector in Jordan is assessed and quantified. Different load management options that would result in reducing the maximum demand on electricity by the industrial sector were considered. The potential for reducing the peak load of the Jordan electrical power system by load management within the industrial sector (medium industrial plants) is estimated to be 22.2 MW.

Analysis of interrelationships between photovoltaic power and battery storage for electric utility load management

The impact of photovoltaic power generation on an electric utility's load shape under supply-side peak load management conditions is explored. Results show that some utilities utilizing battery storage for peak load shaving might benefit from use of photovoltaic (PV) power, the extent of its usefulness being dependent on the specific load shapes as well as the photovoltaic array orientations. Typical utility load shapes both in the eastern (at Rayleigh, NC) and in the western (at Hesperia, CA) parts of the USA are examined for this purpose. It is concluded that while photovoltaic power generation seems to present a bigger impact on the load of the western utility, both utilities will experience considerable savings on the size of the battery system required to shave the peak loads as well as in the night-time base capacity required to charge the battery.< <ETX xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">&gt;</ETX>

Energy conservation and resource utilisation in waste-water treatment plants

The operation of waste-water treatment plants is to a large extent energy-dependent. This paper examines the energy requirements of these plants and explores ways of conserving energy through electrical and thermal load management and resource recovery and utilisation. The gas produced during the process of anaerobic digestion can be used to drive packaged CHP systems for local heat and power generation. Results from pilot installations indicate that these systems can provide electricity at a lower unit cost than the national grid, giving acceptable pay-back periods.

Electric utility energy conservation and load management programmes: R & D opportunities

During recent years, electric utilities have begun a variety of new programmes to manage their future load growth. In many cases, these conservation and load management (C/LM) programmes serve as alternatives to traditional electricity supply resources. Additional development of planning, analysis and evaluation methods is needed before utilities can fully rely on these C/LM programmes as legitimate electric system resources. This paper discusses several important research topics. These topics include better use of data from evaluations of C/LM programmes to improve demand forecasting models, development of models to predict participation in future utility C/LM programmes, review of existing integrated resource planning models, assessment of alternative regulatory treatment of C/LM programmes by state public utility commissions, and identification of better ways to disseminate results on effective C/LM programmes among utilities.

A case for domestic electrical load management

SYNOPSIS There is, nowadays, an increasing social awareness of the need to make better use of all our resources, and one of these resources is our extensive investment in electricity generation and distribution systems. At the present time such systems have sufficient capacity to cope with maximum peak loads that occur infrequently and only for short periods. The average load factor is significantly below unity. Furthermore, as the demand for power inevitably increases, the capacity of the supply and distribution systems simultaneously have to be enlarged to maintain this margin of excess capacity. A case is presented here for the use of existing technology to facilitate a gradual transition to a more cost effective basis for electricity consumption and supply. The basis of the proposed method lies in domestic load management. A research team of architects and engineers is suggested.

Development of an On-Farm Electrical Load Management System

ABSTRACT FARMERS paying electrical demand charges may lower their total electrical bills by reducing their peak demands. Electrical load management theory was applied to the design of an electrical load management system for a farm-scale feed and grain center. Advanced computer technology and customized logic was utilized to reduce peak demand during a typical harvest day from 23.9 to 11.4 kW and to improve the daily load factor from 53 to 97%.