power systems loss

How Solar PV Installations Within Electrical Distribution Network Affect Overall System's Loss?

2024-06-30T20:42:00.001+08:00

The integration of solar photovoltaic (PV) installations within an electrical distribution network can have several impacts on the overall system's losses. Here are some key considerations:

1. Reduction in Transmission and Distribution Losses:

Localized Generation: Solar PV systems generate electricity close to the point of consumption (e.g., on rooftops or within local communities). This localized generation reduces the distance electricity needs to travel from central power plants, thereby reducing transmission and distribution (T&D) losses.
Reduced Load on Grid: When solar PV systems generate power, they supply part of the local demand, reducing the overall load on the distribution network. This can lead to a reduction in the losses associated with high current flows through distribution lines and transformers.

2. Impact on Voltage Levels:

Voltage Regulation: Solar PV systems can contribute to voltage regulation within the distribution network. Properly managed, they can help maintain stable voltage levels, which can reduce losses caused by voltage drops along the distribution lines.
Voltage Rise: However, high penetration of solar PV can lead to voltage rise issues, especially in low-load conditions. This may require additional grid infrastructure or voltage regulation equipment, which could impact overall system losses.

3. Load Balancing and Peak Shaving:

Peak Demand Reduction: Solar PV systems often generate the most electricity during peak sunlight hours, which can coincide with periods of high electricity demand. By shaving the peak demand, solar PV can reduce the need for peaking power plants and associated losses.
Load Shifting: The presence of solar PV can influence the load profile of the distribution network. For example, during sunny days, the daytime load may decrease significantly, leading to lower losses. However, during cloudy days or at night, the load may shift back to the grid, potentially increasing losses if the grid is not well-prepared to handle such fluctuations.

4. Reverse Power Flow:

Bidirectional Flow: High levels of solar PV penetration can cause reverse power flow, where excess generated power flows back from the distribution network to the transmission network. This can lead to additional losses if the grid infrastructure is not optimized for bidirectional power flow.
System Design: Properly designed distribution systems that accommodate bidirectional flow and incorporate advanced grid management technologies can help mitigate additional losses.

5. Impact on Distribution Transformers:

Reduced Loading: Solar PV can reduce the loading on distribution transformers by supplying local loads, which can decrease transformer losses.
Increased Wear and Tear: Frequent cycling and variable loading due to fluctuating solar generation can affect transformer performance and longevity, potentially leading to increased losses if not managed properly.

In summary, the integration of solar PV installations within the electrical distribution network can have a net positive impact by reducing overall system losses, primarily through localized generation and peak shaving. However, careful management of voltage levels, load balancing, and grid infrastructure is necessary to fully realize these benefits and mitigate any potential negative effects such as voltage rise or increased wear on equipment. Advanced grid technologies, such as smart inverters and grid management systems, can play a crucial role in optimizing the integration of solar PV and minimizing system losses.

ChatGPT Answers: What is the typical ratio between non-technical and technical losses in a distribution utility?

2023-02-26T17:56:00.002+08:00

What is the typical ratio between non-technical and technical losses in a distribution utility?

The typical ratio between non-technical and technical losses in a distribution utility can vary depending on a range of factors such as the location of the utility, the age and condition of the distribution system, and the regulatory environment. In general, however, technical losses tend to be higher than non-technical losses.

Technical losses are caused by the physical characteristics of the electric distribution system, such as resistance in transmission and distribution lines and equipment inefficiencies, and can account for up to 8-15% of total energy losses in a distribution utility. Non-technical losses, on the other hand, are caused by theft and fraud, meter inaccuracies, and billing errors and can account for up to 5-7% of total energy losses in a distribution utility.

However, it's important to note that the ratio between technical and non-technical losses can vary significantly depending on the specific circumstances of each distribution utility. For example, utilities that operate in areas with high levels of theft and fraud may have a higher proportion of non-technical losses than technical losses. As such, it's essential for utilities to conduct regular assessments of their energy loss profile and implement effective energy loss management strategies to minimize both technical and non-technical losses.

ChatGPT Answers: How billing timing difference affects systems loss data?

2023-02-26T17:50:00.004+08:00

How billing timing difference affects systems loss data?

Billing timing differences can have an impact on power system loss data, especially if the data is being used for analysis or performance monitoring purposes. This is because billing data is typically collected at different times than system loss data, and these differences can affect the accuracy and reliability of the data.

One potential issue is that billing data is often collected on a monthly or quarterly basis, whereas system loss data may be recorded at a higher frequency, such as every 15 minutes or hourly. This means that the billing data may not accurately reflect changes in power consumption or losses that occur on a more granular time scale.

Another potential issue is that billing data is usually based on customer meter readings, which are affected by a range of factors, such as meter accuracy, measurement errors, and tampering. This can result in inaccuracies in the billing data, which can in turn affect the accuracy of system loss data that is derived from it.

To mitigate these issues, it's important to ensure that the billing data used for analysis is as accurate and reliable as possible. This may involve implementing measures such as regular meter calibration, meter data validation and estimation, and quality assurance checks. Additionally, it may be necessary to align the timing of billing and system loss data as closely as possible, for example by using sub-hourly meter readings or other forms of high-frequency data collection.

ChatGPT Answers: How to Reduce Technical Losses in a Electric Distribution Utility Network?

2023-01-14T18:24:00.008+08:00

ChatGPT Answers: How to Reduce Technical Losses in a Electric Distribution Utility Network?

There are several ways to reduce technical losses in an electric distribution utility network:

Optimize network design: Properly designing the distribution network, such as using the correct size and type of equipment, can help minimize losses.
Improve system efficiency: Upgrading equipment and using advanced technologies, such as smart meters and advanced metering infrastructure, can improve system efficiency and reduce losses.
Conduct regular maintenance: Regularly maintaining equipment can help identify and repair any issues that may be causing losses.
Implement load management strategies: By managing and reducing peak loads, utilities can reduce losses and improve overall system efficiency.
Monitor and measure losses: Regularly monitoring and measuring losses can help identify areas where improvements can be made and track progress over time.
Use of distributed energy resources (DERs) such as solar, wind and storage which can help utilities to reduce their transmission and distribution losses by reducing their need to import power from far away sources.
Using advanced analytics and machine learning algorithms, to detect and diagnose the issues and predict the future trends which can help utilities to reduce the technical losses.

ChatGPT Answers: How to start Machine Learning for Electricity Pilferage Detection with Customer Data as variables?

2023-01-14T18:08:00.008+08:00

ChatGPT Answers: How to start Machine Learning for Electricity Pilferage Detection with Customer Data as variables?

1. Starting a machine learning project for electricity pilferage detection with customer data as variables can be a multi-step process. Here's an overview of the steps you might take:

2. Data collection: Collect customer data such as hourly, daily, or monthly electricity consumption levels, as well as customer demographics, location and history of consumption. This data can be obtained from the utility company's billing system or smart meter data.

3. Data preprocessing: Clean and prepare the data for use in a machine learning model. This can include normalizing the data, handling missing values and outliers, and encoding categorical variables. It's important to have a good understanding of the data and its characteristics to be able to make appropriate preprocessing decisions.

4.Feature Engineering: Create new input variables (features) from the raw data that can be used to train the machine learning models. These features can be based on the consumption patterns, customer characteristics, weather, location, etc. They should be selected carefully to maximize their explanatory power and avoid introducing unnecessary noise.

5. Model selection: Choose an appropriate machine learning model for the task. There are many different types of models to choose from, such as decision trees, random forests, neural networks, etc. The choice of model will depend on the specific characteristics of the data and the problem at hand.

6. Model training: Use the preprocessed and feature-engineered data to train the chosen machine learning model. This typically involves splitting the data into a training set and a test set, and using the training set to train the model.

7. Model evaluation: Evaluate the performance of the trained model using the test set, and use the evaluation metric such as precision, recall, F1 score or AUC-ROC to compare the model performance.

8. Model Deployment: After the model is trained and has achieved a satisfactory level of performance, it can be deployed in production to monitor customer electricity usage in real-time, flagging any suspicious usage patterns that could indicate pilferage.

9. Model monitoring: Continuously monitor the model performance and update the model if needed.

It's important to note that machine learning models are only as good as the quality of the data and the way it's been feature engineered, so it's important to have a team of experts (Data scientists/Statisticians) that can do the preprocessing, feature engineering and model selection correctly. Additionally, It's also important to keep the data privacy in mind, and to make sure that any personal information is handled in accordance with relevant regulations and laws.

ChatGPT Answers: Best Programming Platform to Use for Pilferage Detection Using Machine Learning?

2023-01-14T18:03:00.001+08:00

ChatGPT Answers: Best Programming Platform to Use for Pilferage Detection Using Machine Learning?

There are several programming platforms that are commonly used for building machine learning models, including:

1. Python: Python is a widely-used, high-level programming language that has a large and active community of developers. It has a number of powerful libraries and frameworks for machine learning, including TensorFlow, PyTorch, scikit-learn, and pandas. These libraries make it easy to build and train machine learning models, as well as to perform data preprocessing and visualization.

2. R: R is a programming language and software environment for statistical computing and graphics. It has a number of powerful libraries and frameworks for machine learning, including caret, mlr, and randomForest. R also has a large and active community of developers, and is particularly well-suited for statistical modeling and data visualization.

3. Java: Java is a widely-used, high-level programming language that has a mature ecosystem for building machine learning applications. It has libraries such as Weka and MOA that make it easy to build and train machine learning models, as well as to perform data preprocessing and visualization.

4. Julia: Julia is a high-performance, high-level programming language for technical computing, with syntax that is familiar to users of other technical computing environments. Julia has a fast-growing ecosystem for machine learning, including Flux.jl, MLJ.jl and many others.

Ultimately, the best programming platform to use will depend on your specific needs and the requirements of your project. Python is a great place to start because of the large number of libraries and support available, but it's always good to consider other options as well depending on the project and team requirements.

ChatGPT Answers: How to Detect Electricity Pilferage using Machine Learning from Customer Data?

2023-01-14T18:00:00.002+08:00

ChatGPT Answers: How to Detect Electricity Pilferage using Machine Learning from Customer Data?

Using machine learning (ML) to detect electricity pilferage from customer data can be an effective approach for utility companies. Here's an overview of how this can work:

Data collection: Utility companies can collect data on customer electricity usage patterns, such as hourly, daily, or monthly consumption levels, as well as customer demographics, location and history of consumption.
Data preprocessing: The data must be cleaned, transformed and prepared so that it can be used to train the machine learning models. This can include normalizing the data, handling missing values and outliers, and encoding categorical variables.
Feature engineering: The process of creating new input variables (features) from the raw data. In the case of electricity pilferage this could be creating features like load factor (ratio between energy consumed and peak energy consumption), Non Intrusive Load monitoring (NILM) to detect if there is any hidden consumption in addition to the reported consumption, or using signal processing techniques to detect abnormal patterns from the time series data of electricity consumption.
Model training: Using the preprocessed and feature-engineered data, ML models such as decision tree, Random Forest, Neural Network and so on can be trained to detect abnormal electricity usage patterns that may indicate meter tampering or energy theft.
Model deployment: Once the model is trained and has achieved a satisfactory level of performance, it can be deployed in production to monitor customer electricity usage in real-time, flagging any suspicious usage patterns that could indicate pilferage.
Evaluation: After deploying the model, it is important to evaluate its performance. Commonly used evaluation metric in this scenario is the precision, recall and F1 score or AUC-ROC

It's important to note that these models are only as good as the quality of the data and the way it's been feature engineered so it's important to have a team of experts (Data scientists/Statisticians) that can do the preprocessing, feature engineering and model selection correctly.

ChatGPT Answers: How to Detect Electricity Pilferage?

2023-01-14T17:57:00.000+08:00

ChatGPT Answers: How to Detect Electricity Pilferage?

There are several ways to detect electricity pilferage, also known as meter tampering or energy theft. Some common methods include:

Visual inspections: Utility companies can physically inspect meters and electrical connections to look for signs of tampering, such as bypassed or damaged meters.

Smart meters: These digital meters can detect and report abnormal usage patterns, such as usage during hours when the customer is not at home, or usage that exceeds expected levels.

Data analysis: Utility companies can analyze electricity usage data to identify patterns of energy consumption that may indicate tampering, such as usage spikes at night or on weekends.

On-site investigation: Utility companies can perform on-site investigations to check for connections to the electricity supply that bypass the meter, check for tampered with or bypassed meters or hidden unauthorized consumption sources.

Mobile detection units: Some companies use mobile detection units that can be moved to different locations to detect energy theft. These units use infrared cameras, ultrasonic sensors, and other advanced technologies to detect heat and sound that may be generated by tampered meters or unauthorized connections.

Overall, detecting electricity pilferage requires a combination of different methods and technologies. It's important for utility companies to have a comprehensive approach and continuously monitor for signs of tampering to protect the revenue, their electricity grid and ensure fair billing to customers.

Data Science for Distribution Loss Management

2022-07-16T20:16:00.002+08:00

DATA SCIENCE FOR DISTRIBUTION LOSS MANAGEMENT

Data Science as defined in wikipedia is is an interdisciplinary field that uses scientific methods, processes, algorithms and systems to extract knowledge and insights from noisy, structured and unstructured data, and apply knowledge from data across a broad range of application domains. Data science is related to data mining, machine learning and big data.

Data science is a "concept to unify statistics, data analysis, informatics, and their related methods" in order to "understand and analyse actual phenomena" with data. It uses techniques and theories drawn from many fields within the context of mathematics, statistics, computer science, information science, and domain knowledge. However, data science is different from computer science and information science. Turing Award winner Jim Gray imagined data science as a "fourth paradigm" of science (empirical, theoretical, computational, and now data-driven) and asserted that "everything about science is changing because of the impact of information technology" and the data deluge.

Data Science on Distribution loss management is of no exception.

The rapid transformation of the electricity sector increases both the opportunities and the need for Data Analytics. In recent years, various new methods and fields of application have been emerging. As research is growing and becoming more diverse and specialized, it is essential to integrate and structure the fragmented body of scientific work. We therefore conduct a systematic review of studies concerned with developing and applying Data Analytics methods in the context of the electricity value chain. First, we provide a quantitative high-level overview of the status quo of Data Analytics research, and show historical literature growth, leading countries in the field and the most intensive international collaborations. Then, we qualitatively review over 200 high-impact studies to present an in-depth analysis of the most prominent applications of Data Analytics in each of the electricity sector’s areas: generation, trading, transmission, distribution, and consumption. For each area, we review the state-of-the-art Data Analytics applications and methods. In addition, we discuss used data sets, feature selection methods, benchmark methods, evaluation metrics, and model complexity and run time. Summarizing the findings from the different areas, we identify best practices and what researchers in one area can learn from other areas. Finally, we highlight potential for future research. Source: sciencedirect.com

ACCR(Aluminum Conductor Composite Reinforced) by 3M vs. ACSR

2019-11-27T21:02:00.001+08:00

ACCR versus ACSR

Customer demand for power grows, renewable generators wait for interconnection, and intermittent resources demand more flexibility from aging infrastructure. Yet dense populations, environmental concerns, permitting requirements, and land scarcity intensify the schedule, budget and regulatory risks of building or rebuilding lines.

To solve these challenges, 3M developed Aluminum Conductor Composite Reinforced (3M™ CCR). 3M ACCR is an advanced transmission conductor designed to replace ACSR or ACSS on existing structures at the same tensions and clearances, giving you up to twice the capacity without the risks of a major construction project. Your line is in service fast, within budget, and with minimal environmental impacts. And the available trapwire options may help improve the line’s efficiency.

To know more about 3M's ACCR, please their product catalogue.

ACCR 3M Catalogue

Philippine's Energy Regulatory Commission Lowers Systems Loss Cap

2018-03-07T12:55:00.000+08:00

ERC Lowers System Loss Cap

BY JORDEENE SHEEX LAGARE ON FEBRUARY 23, 2018
Manila Times

The Energy Regulatory Commission (ERC) has reduced system loss charges that distribution utilities (DUs) can pass on to their consumers.

In a statement on Wednesday, ERC said that under its Resolution 20, Series of 2017, DUs would have a 6.5-percent distribution loss this year. This would be gradually reduced annually until it reaches 5.5 percent by 2021.

Electric cooperatives (ECs), which will be grouped into three clusters based on technical considerations, shall impose a 12-percent cap for 2018.

They can charge between 8.25 percent and 12 percent until 2022 onward, depending on which cluster they are assigned to.

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DISTRIBUTION SYSTEM’S LOSS RISK MANAGEMENT

2013-06-01T20:53:00.000+08:00

Factors/Risks associated with increase in distribution’s systems loss

Increase in utility’s system’s kWh loss can be attributed to many factors. We all know that the components of a utility’s systems loss can be from technical loss or from non-technical loss. As a review, technical loss is the inherent properties of electrical equipment and devices during operation while non-technical loss is the result of electricity pilferage, error in meter reading, etc.

An electric distribution utility’s goal in dealing with losses includes the reduction of over-all system’s loss to the least possible level. However, there are some events or situations that greatly affect the over-all value of the kWh lost. Identifying these risks is of great importance since the effect of this can be felt for a long period of time especially for utilities which rely on cumulative computation of losses.

Enumerated below are the typical risks faced by an electric utility which if not taken cared of can greatly impact the kWh loss and the revenue of the company.

Increase in Electricity Pilferage - Electricity Pilferage is a component of system's loss particularly in non-technical loss. An increase in the volume of electric pilferage due to increase of number of cases or decrease in apprehension activities affects greatly the over-all system's loss. Some causes of these increases can be linked to the lack of apprehending personnel to catch these violators, the presence of syndicated pilferers which operates in large number and from undetected power customers who engages in pilferage.

Increases in Unbilled/Erroneously Billed Customers - Unbilled customers are a connected customer who utilizes electricity but are not read/billed due to records and maintenance issues. Unbilled electricity can also affect the company’s systems loss reporting. One known cause of this risk is from poor meter inventory and recording. There are some cases especially during emergencies where the meters are installed in the site and no proper recording and tagging was done thus the customer is enjoying the use of electricity and not being billed for its consumption.

High Loss Distribution Network Configuration – An Electric Distribution System is a network of line and substation interconnections which if not configured strategically can produce high technical losses. This happens when overloading of distribution lines are present caused by sudden increase in loads or undersized wires. As we all know, wires with smaller size produces more loss compared to wires with larger size.

These are just some of the typical risk faced in managing system’s loss in a distribution utility. Any of these three factors can influence whether to improve or worsen the present situation.

TYPICAL ELECTRIC PILFERAGE DETECTION METHODS

2013-05-26T17:38:00.000+08:00

How to detect possible electricity pilferage?

We all know that system’s loss is composed primarily of technical loss and non-technical loss. Technical loss is the inherent property of all electrical devices during operation while non-technical losses are caused by electricity theft and/or metering inaccuracies. Technical loss can be determined through computations and the use of measuring devices. On the other hand, non-technical loss cannot be measured nor be computed; instead one has to have various methods just to detect such loss.

Various methods of detecting are used in identifying users who engaged in these criminal activities varying to the type of pilferage committed. Typically, there are three types of customers found in any distribution utility namely; residential, commercial, and industrial. These three types of customers’ uses different types of meters thus, different types of pilferage can also be done.

Of course, before your detect any pilferage one must first understand how stealing of electricity are done but unfortunately, due to some security reasons, this topic will not be discussed here instead, we are only going to give you the general idea.

The detection methods can be categorized into two; Physical detection and Detection through Customer Consumption. Although the latter can be subjective, this however will give you head’s up on what you are dealing with.

Physical Detection – is done by looking for traces of tampering in the utility’s meter seal, tampering in the service connection, tampering in the meter accuracy seal, foreign wires (used for direct tapping) not specified in construction standard, etc. Detection of pilferage merely by looking at the customer connection can be quite hard if it was concealed carefully and no traces can be found using the naked eye.

Customer Consumption – When a customer steals electricity, there is a high possibility that their regular consumption (as metered) will significantly drop. Also, one way of detecting a pilferage is when their recorded energy consumption is not proportional to the devices connected in their premises. This method is in no way 100% accurate but this can trigger investigation for the reason why their consumption dropped.

COMPUTATION OF TECHNICAL POWER LOSS FOR FEEDERS USING LOAD FACTOR AND LOAD LOSS FACTOR TECHNICAL PAPER

2013-05-13T17:34:00.000+08:00

Author: Sarang Pande and Prof. Dr. J.G. Ghodekar

ABSTRACT: Power system losses can be divided into two categories: technical losses and non-technical losses. Technical losses are naturally occurring losses (caused by actions internal to the power system) and consist mainly of power dissipation in electrical system components such as transmission lines, power transformers, measurement systems, etc. Technical losses result from the impedance of the network components such as electric lines/ cables, transformers, metering and protecting equipment etc. Non-technical losses, on the other hand, are caused by theft, metering inaccuracies. In this paper a method for energy loss calculation is presented.

INTRODUCTION: System loss is basically arithmetic difference between the units purchased from bulk suppliers and the units billed to consumers in the respective period. The total system loss for any given period is expressed as percentage of total energy input in the system and is computed as follows:

Total distribution loss = (Energy input- Energy sold)/ Energy input/ 100

The total losses comprises of technical loss and commercial loss. The commercial loss mainly consists of losses due to theft of energy and unrecovered billed amount. While, technical losses are the losses occurred in the electrical elements during transportation of energy from the source to consumer end and mainly comprises of ohmic and iron losses. Technical loss is an inevitable consequence of transfer of energy across transmission and distribution networks.

CONCLUSION: A paper demonstrates the capability of Load factor and load loss factor to calculate the power losses of the network. A method for power loss calculation is presented, the methodology is simple to implement. The data used is readily available with the engineers of power Distribution Company. The results obtained can be used for financial loss calculations and can be presented to regulator for tariff determination process.

For Complete access of the file…

INVERTER TECHNOLOGY FOR ENERGY SAVING GUIDE

2013-04-13T17:27:00.000+08:00

How to save energy in using inverter technology?

An inverter used either in air conditioning or refrigeration basic benefit is its significant energy saving capabilities. Inverter technology allows the air conditioner/refrigerator automatically vary its power output to specifically maintain room temperature at a desired or comfortable level. Basically, the inverter is used to control the speed of the compressor motor to allow continuously regulated temperature. In contrast, a non-inverter appliance maintains the temperature by repeatedly switching power on and off, which consumes much more electrical energy upon starting.

The variable-frequency drive uses a rectifier to convert the incoming alternating current (AC) to direct current (DC) and then uses pulse-width modulation in an electrical inverter to produce AC of a desired frequency. The variable frequency AC drives a brushless motor or an induction motor. As the speed of an induction motor is proportional to the frequency of the AC, the compressors runs at different speeds. A microcontroller can then sample the current ambient air temperature and adjust the speed of the compressor appropriately. The additional electronics add to cost of equipment and operation. Conversion from AC to DC, and then back to AC, can cost as much 4 - 6% in energy losses for each conversion step.(Wikipedia)

Eliminating stop-start cycles increases efficiency, extends the life of components, and helps eliminate sharp fluctuations in the load the air conditioner places on the power supply. Ultimately this makes inverter air conditioners less prone to breakdowns, cheaper to run, and the outdoor compressor is generally quieter than a standard air conditioning unit's compressor.(Wikipedia)

To illustrate the comparison between devices with inverter models and non-inverter models, refer to the picture below from Hitachi.

TYPICAL LOSS FOR AMORPHOUS-METAL CORE DISTRIBUTION TRANSFORMERS

2013-03-23T21:35:00.000+08:00

Typical Loss for Amorphous-Metal Core Distribution Transformers.

The losses shown in the table are the typical values of a amorphous-metal cored distribution transformers. Core loss and Winding loss (watts) varies relatively as with the increase of the distribution transformer's kVA capacity. Also shown are he respective kilo-watthour loss in annual basis for different transformer capacity in 30% and 40% load factor. Annual kwh are based on peak transformer kW loading equal to kVA size.

TYPICAL LOSS FOR SILICON-CORE DISTRIBUTION TRANSFORMER

2013-02-05T20:59:00.001+08:00

Typical Loss for Silicon-Core Distribution Transformers

The losses shown in the table are the typical values of silicon-cored distribution transformers. Core loss and Winding loss (watts) varies relatively as with the increase of the distribution transformer's kVA capacity. Also shown are he respective kilo-watthour loss in annual basis for different transformer capacity in 30% and 40% load factor. Annual kwh are based on peak transformer kW loading equal to kVA size.

TYPICAL NO-LOAD LOSS AND LOAD LOSS FOR POWER TRANSFORMERS

2013-01-04T18:22:00.001+08:00

Typical No-Load loss and Load loss for Power Transformers according to MVA capacity.

No-load loss and Load loss in Power Transformers varies significantly depending on different factors. Here you can find the typical value for the no-load loss and load loss according to power transformers having Load Tap changers and those having none. Different MVA capacity means also having different values for the power transformers' no-load and load loss.

Typical No-Load and Load Loss for Substation Power Transformer Units Without Load Tap Changers.

*Annual kWh losses are based on transformer loading at nameplates, loss factor of 0.3 and auxiliary loss factor of 0.1.

Typical No-Load and Load Loss for Substation Power Transformer Units With Load Tap Changers.

*Winding losses are based on maximum raise or lower LTC tap position setting.
**Annual kWh losses are based on transformer loading at nameplates, loss factor of 0.3 and auxiliary loss factor of 0.1.

CLASSES OF INCANDESCENT LAMPS

2012-09-25T21:07:00.001+08:00

Classes of incandescent lamps as cataloged by the manufacturers.

Large lamps, miniature lamps, and photographic lamps are the three major groups of incandescent lamps as divided and cataloged by the manufactures. As a summary, large lamps are those normally used for interior and exterior general and task lighting. Miniature lamps are generally used in automative, aircraft, and appliance applications. Photographic lamps, as the name implies, are used in photography and projection service.

Some of the main classes of large lamps are as follows:

General Service. These are for general lighting on 120-V circuits. Sizes range from 15 to 1500W with efficacies of 8 to nearly 23 lm/W. Lamps rated at 130 and other voltages are also available - consult catalogs or sales representatives of lamp manufacturers for specific listings.

High Voltage. High-voltage incandescent lamps are designed for operation directly on circuits of 220 to 300V. They are less rugged and have a lower efficacy than general-service lamps.There are also general-service incandescent lamps for 277-V circuits. One manufacturer cautions that such lamps be enclosed if used on high-capacity, lowe impedance electrical distribution systems.

Extended Service. These have a life of 2500 or more hours andare intended for use in applications where lamp failure causes an inconvenience, a nuisance, or a hazard to replace the lamp, or where replacement labor is expensive. They are less efficient than general-service.

General Lighting Tungsten-Halogen. These are compact, have better lumen maintenance, and provide a whiter light and a longer life.

Reflectorized. These are group of lamps embodying integral reflecting surfaces, bowl-silvered lamps are employed in direct-lighting equipment in which it is desired to shield the filament from view but principally in indirect equipment. Initial loss of light output due to the silvering is 6 to 10%; the rate of decline of light output is considerably greater than in clear-bulb lamps of corresponding sizes.

Small Tungsten-Halogen Lamps. Families 1 3/8 - and 2-in-diameter,12-V models having internal multifaceted reflectors, providing a range of beam spreads for accent and display lighting. Dichroic reflector coatings reduce approximately two-thirds of the heat in the beam by emitting infrared energy to the rear, thus deceasing fading of color-perishable items that are illuminated.

Rough and Vibration Service. These lamps are for use where lamps are subjected to shock and vibration while in use. Filament construction differs. Rough-service lamps are available from 25 to 200W, whle those for vibration service range from 40 to 150W.

Street Lighting. These lamps are availalbe for series burning and multiple burning. The former are rated according to lumen output and the latter according to watts. Ingeneral the lumen maintenanceof series lamps is better than that of multiple lamps. The latter are rated on a basis such that their average lumens throughout lifeare approxiamtely equivalent to those of series lamps of corresponding sizes.

Decorative Lamps. Incandescent lamps in many bulb shapes, bases, and wattages are available for a variety of decorative and architectural lighint applications.Some have specific requirements regarding burning position, shielding from moisture, etc., as covered in technical literature of the fluorescent lamps.

WOOD ARMS VS. STEEL ARMS FOR TRANSMISSION SYSTEM

2012-09-25T20:31:00.000+08:00

Short Comparison between using wooden arms vs. steel arms in power transmission system.

Wooden crossarms used in power transmission system are lower in cost than steel arms of the same strength and, aside from the shorter life, the possibility of being shattered by lightning, and the risk of burning due to leakage current at 345kV and above, are satisfactory. On wood pole construction, the advantages of steel arms - resistance to lightning damage and longer life - are not usually sufficient to offset the insulation strength of wood crossarms.

In any event, lightning damage to arms is usually not a major operating problem; and on lines thoroughly shielded with overhead ground wires, crossarm and pole damage is practically eliminated. At higher voltages, crossarms are sometimes equipped with bonding wires to prevent leakage current from burning.

ENERGY SAVING THROUGH LED LAMPS (LIGHT EMITTING DIODE LAMPS) USE

2012-09-21T19:25:00.000+08:00

The use of light emitting diodelamps(LED) to minimize electrical losses in distribution utilities.

Man’s quest for energy conservation abled him to create many forms of technology innovations. This includes the utilization of LED to make the LED lamps. LED or Light-Emitting Diode is an electronic device able to emit light through direct current supply source. It is a type of lamp that said to be in solid-state form. LED lamps, like compact fluorescent lamps have a higher energy efficiency compared to the traditional incandescent lamps.

The light output of a single light-emitting diode (LED) is small compared to a single unit compact fluorescent lamp or incandescent lamp. To produce light output that would equal or even exceed those of conventional devices for lighting, LED lamps uses multiple numbers of diodes. For practicality, LED lamps are typically created with bases identical to incandescent lamps to make it interchangeable with these traditional devices. Since LED is a semi-conductor, LED lamp requires direct current source to operate. To make it useable to AC powered supply, LED lamps are usually operated with external or internal rectifier circuits able to produce the LED lamps DC requirement.

Due to LED lamps energy efficiency characteristic, LED lamps are used not only to light up rooms in houses and buildings but also to some other lighting applications like flashlights, car headlights, light decorations, etc. Street lighting also greatly benefited to the use of LED lamps because it requires lesser electrical energy as compared to sodium-light lamps and Halogen lamps with similar illumination output.

One major known disadvantage in using LED lamps is it requires higher initial cost compared to incandescent and fluorescent lamps. Since LEDs when used in high temperatures becomes degraded and damaged, LED lamps usually requires heat sinks and cooling fins to dissipate the heat produce by the device and the environment.A LED does not emit light in all direction unlike those incandescent lamps making it more advantageous. A directed light requires less Lumen compared to lighting sources which would need reflectors or lenses to do the same. For illuminating a 360° orbit, the benefits of LED are much smaller.

To understand more the comparison of LED lamps to other lighting technologies, a simple electrical comparison from Wikipedia is provided below.

Incandescent lamps (light bulbs) generate light by passing electric current through a resistive filament, thereby heating the filament to a very high temperature so that it glows and emits visible light. A broad range of visible frequencies are naturally produced, yielding a "warm" yellow or white color quality. Incandescent light is highly inefficient, as about 98% of the energy input is emitted as heat. A 100 W light bulb for 120 V operation emits about 1,700 lumens, about 17 lumens/W; for 230 V bulbs the figures are 1200 lm and 12 lm/W. Incandescent lamps are relatively inexpensive to make. The typical lifespan of an AC incandescent lamp is around 1,000 hours. They work well with dimmers. Most older light fixtures are designed for the size and shape of these traditional bulbs.

Fluorescent lamps (light bulbs) work by passing electricity through mercury vapor, which in turn emits ultraviolet light. The ultraviolet light is then absorbed by a phosphor coating inside the lamp, causing it to glow, or fluoresce. While the heat generated by a fluorescent lamp is much less than its incandescent counterpart, energy is still lost in generating the ultraviolet light and converting this light into visible light. If the lamp breaks, exposure to mercury can occur. Linear fluorescent lamps are typically five to six times the cost of equivalent incandescent lamps but have life spans around 10,000 and 20,000 hours. Lifetime varies from 1,200 hours to 20,000 hours for compact fluorescent lamps. Most fluorescent lamps are not compatible with dimmers. Those with "iron" ballasts flicker at 100 or 120 Hz, and are less efficient. The latest T8-sized triphosphate fluorescent lamps made by Osram, Philips, Crompton and others have a life expectancy greater than 50,000 hours, if coupled with a warm-start electronic ballast. The life expectancy depends on the number of on/off cycles, and is lower if the light is cycled often. The efficiency of these new lamps approaches 100lumens/W. The efficiency of fluorescent tubes with modern electronic ballasts and compact fluorescents commonly ranges from 50 to 67 lumens/W. For comparison, general household LED bulbs available in 2011 emit 64lumens/W, with the best LED bulbs coming in at about 100 lumens/W.

ENERGY SAVING THROUGH CFL (COMPACT FLUORESCENT LAMPS) USE

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The use of compact fluorescent lamps to minimize electrical losses in distribution utilities.

Compact Fluorescent Lamps or popularly known as CFL, as the name implies is a type of fluorescent lamps carefully designed to take the role of an incandescent lamps. Compact Fluorescent Lamps are specially made with fittings that would readily replace the existing incandescent lamps. Like any other typical fluorescent lamps, compact fluorescent lamp also contains mercury and also utilizes a compact electronic ballast to operate.

Compact Fluorescent Lamps was first introduced as a screw type lamp by Philips in 1980 with its integral magnetic ballast. Compact Fluorescent Lamps is categorized into two types: integrated and non-integrated. Integrated Compact Fluorescent Lamps simply means that the tube and the ballast of the lamp are taken as a single unit. On the other hand, non-integrated compact fluorescent lamps are those lamps that have the ballast separately installed from the lamp bulb.

The rated life of a compact fluorescent lamps ranges from 8 to 15 times that of incandescent.Compact fluorescent lamps typically have a rated lifespan of 6,000 to 15,000 hours, whereas incandescent lamps are usually manufactured to have a lifespan of 750 hours or 1,000 hours.(Wikipedia)

The lifetime of any lamp depends on many factors, including operating voltage, manufacturing defects, exposure to voltage spikes, mechanical shock, frequency of cycling on and off, lamp orientation, and ambient operating temperature, among other factors. The life of Compact Fluorescent Lamps is significantly shorter if it is turned on and off frequently. In the case of a 5-minute on/off cycle the lifespan of Compact Fluorescent Lamps can be reduced to "close to that of incandescent light bulbs". The U.S. Energy Star program suggests that fluorescent lamps be left on when leaving a room for less than 15 minutes to mitigate this problem.(Wikipedia)

Compact fluorescent lamps produce less light later in their lives than when they are new. The light output decay is exponential; with the fastest losses being soon after the lamp is first used. By the end of their lives, compact fluorescent lamps can be expected to produce 70–80% of their original light output. (Wikipedia)

Compact Fluorescent Lamps became popular due to its extremely high energy efficiency as compared to a regular incandescent lamp. Compared to incandescent lamps, initial cost for compact fluorescent lamps is relatively higher. However, compact fluorescent lamps can save over five times its purchase price in electrical energy costs over the lamp’s lifetime. In terms of energy saving, compact fluorescent lamps only utilizes up to one-fifth of electric power in contrast to incandescent lamps. With the same amount of illumination, the use of compact fluorescent lamps saves the use of extra energy when using the equivalent incandescent lamps.

A similar wattage rating of an incandescent lamps and compact fluorescent lamps produces significant difference when it comes to performance. Incandescent lamps uses only a small amount of electricity that is converted to light with the majority is said to be converted to heat. On the other hand, compact fluorescent lamps produce less heat and maximize the use of electric power to produce light.

The uses of compact fluorescent lamps for lighting purposes are greatly encouraged by distribution utilities. Actually, projects for replacing incandescent lamps with compact fluorescent lamps for free are initiated by some governments worldwide to promote the conservation of energy. With a reduced energy demand, distribution utilities can delay putting up additional capacity therefore can also delay the use of their capital expenditures.In addition, reduced energy demand can delay putting up additional generation capacity which later can be harmful to the environment.

TIPS AND TUTORIALS FOR ENERGY SAVING IN AIR CONDITIONING SYSTEMS

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Heating/Ventilation/Air Conditioning Systems Energy Saving Tips

Majority of our electricity consumption are alloted to our conditioning units. Continuous maintenance of this device is necessary to ensure its effectivity and efficiency. This is a guide to follow for you to keep your airconditiong system function reliably. An unmaintained airconditiong system usually consumes more electrical energy compared to that of a well-maintained one.

Regularly...

Keep vents closed in unoccupied areas to preventheating or cooling of storage areas and closets.
Reduce fresh air intake to the minimum necessary forthe type of business.
Treat water in evaporative condensers regularly.
Replace resistance electric heating systems with heatpumps.
Replace old HVAC systems with new energy-efficientsystems.
Install paddle fans, stratotherm fans, or other recirculatingsystems to create air movement. Ceiling temperatures can often be 30° to 40° higher than floortemperatures, and air movement from fans can enhance thecooling ability of air conditioning systems.
Install air conditioner economizers to use outside air tocool buildings when outdoor air is lower than indoor temperatures.
Install time clocks, set-back thermostats, andmicroprocessor thermostats to monitor HVAC systems whenbuildings are unoccupied.
Install intermittent ignition devices on natural gasfurnaces to save natural gas.
Modify flue dampers on natural gas furnaces toincrease burner efficiency.

Monthly ...

Check air filters monthly, and clean or change asneeded.
Check air intake screens monthly, and clean asrequired.
Inspect air dampers monthly, and keep them as airtightas possible.
Check V-belts (fan belts) monthly for frays, cracks, andnicks, and replace as necessary.
Check heat recovery devices monthly for properoperation.
Brush off air conditioner condenser coils monthly.Quarterly ...
Check motors, bearings, and blower fans every threemonths, and lubricate as required.
Check heating and cooling coils every three months,and clean as needed.
Check vacuum blower compartments every threemonths.
Check ducts, vents, and pipes every three months, andrepair any damaged insulation.

Seasonally ...

Check cooling systems in the spring before the coolingseason begins.
Check pulleys and sheaves in the spring and fall foralignment and proper belt tension.
Set thermostats at 78°F or higher for cooling during thesummer.
During the summer, open windows and use only thefan portion of cooling systems when outdoor air is coolerthan indoor temperatures.
Keep doors and windows closed when air conditioningsystems are operating.
Check heating systems in the fall before the heatingseason begins.
During the winter, open shades and blinds on sunnydays to warm buildings naturally, and close them at night toprevent heat loss.
Set thermostats at 68°F degrees or lower for heating inthe winter, and 55°F when buildings are unoccupied. Ifheating is required in warehouses, set thermostats to 50°F .

Annually ...

Check cabinets and brackets once a year, and tightenall bolts and screws as necessary.
Check housings yearly, and remove rust and repaint asrequired.

ENERGY SAVING TIPS FOR HOMES PART2

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Most of the energy used at home, 45%, comes fromheating and cooling systems.

This is a continuation on energy saving tips for homes. Saving electricity in homes not only brings down the monthly bill of the consumer but also helps the electric distribution utility delay its construction of another capacity like substations since the power demand are kept to an enough level. This energy saving tips will help many people lower their monthly electrical consumption.

Major & Small Appliances:

Maintain refrigerator at 37 - 40 degrees F and freezerat 5 degrees F
For cooking small meals, use toaster ovens ormicrowaves
Adjust the flame on gas cooling appliances so it's blue,not yellow
Replace a gas cooling appliance with a unit with anautomatic, electric ignition system
Run the dishwasher in the evening with a full load ofdishes
Air dry dishes in a dishwasher
Regularly clean the lint filter on your dryer and inspectthe dryer vent to ensure it is not blocked
Shut down home computers when not in use
Select appliances (i.e. curling irons, coffee pots, irons)with time limited shut off switches
Replace aging major appliances, TVs and VCRs whenneeded, with energy efficient models
Compare the annual energy consumption and operatingcost for each appliance by looking at the bright-yellow andblack Energy Guide label when shopping for new appliances

Lighting:

Turn off light when not in use
Use task lighting whenever possible instead ofoverhead lighting
Install compact fluorescent lamps (CFPs) in fixtures

Heating and Cooling Tips

Weatherstrip your windows and doorways. Add doorsweeps beneath doors for added insulation.
Check your furnace filter every month during theheating season and replace when it is dirty.
Save on your heating costs by adding insulation to youruninsulated or inadequately insulated attic.
Repair cracks or broken seams in forced-air heatingducts.
Lowering your thermostat while you are not at home orat night while you sleep can save money. For every degreeyou lower your thermostat, you can save approximately 3%on your heating bill. Generally, lowering your thermostat by5° will make an impact on your energy bill.
Close your drapes or blinds at night to keep the heatinside your premises.
During cold weather, seal all openings to cooling units(wall and window air conditioners and outside central airunits) to keep the heat inside your premises.
Don't block heating outlets or return registers withfurniture or other objects.
Choose a high-efficiency model when shopping for anew gas furnace.

Water Heating Tip

Here are some tips that will help you save energy andmoney by using natural gas water heaters and hot waterwisely and efficiently. Today's natural gas water heaters aremore efficient than ever, but here are a few steps that youcan take to maximize that efficiency:
Keep the area around your water heater clean andwell-ventilated.
Water heaters are now being shipped with arecommendation of temperature settings at 120°F. This slows lime buildup and reduces the risk of hot water burns.
Repair leaky hot water faucets and pipes.
Install water flow restrictors in your shower heads andother faucets.
Use warm or cold water to wash clothing whenpossible.
Run the dishwasher only when it is full.
Take short showers rather than baths, to save water.
Never let the hot water run continuously when washingyour face or shaving.
Use the cold water faucet when little water is required.
Water heaters, like heating systems, carry a federallyrequired Energy-Guide sticker. On a water heater, theEnergy Guide shows you the average annual cost for theunit and indicates the "first-hour rating" of the water heater.

ENERGY SAVING TIPS FOR HOMES PART1

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Most of the energy used at home, 45%, comes fromheating and cooling systems.

Saving electricity in homes not only brings down the monthly bill of the consumer but also helps the electric distribution utility delay its construction of another capacity like substations since the power demand are kept to an enough level. This energy saving tips will help many people lower their monthly electrical consumption.

Heating:

Set your home thermostat to a temperature as low ascomfortable (65 - 68 degrees F is suggested) when thehouse is occupied
Set back your thermostat by as much as 10 degrees Fat night or when the house is unoccupied during the day
Set back the thermostat to 50 - 55 degrees F when thehouse is unoccupied for over 24 hours
Install a programmable thermostat to automaticallyprovide the setbacks mentioned above
Close the fireplace damper - except during fireplace use
Reduce heat to unused rooms in the house by closingdoors and heat registers
Replace furnace filters once a month during the heatingseason
Keep objects away from and clean heating registersregularly
Have certified maintenance personnel service andcheck your furnace regularly
Minimize the use of kitchen, bath, and other ventilatingfans or install a timer switch on them
Install insulating gaskets behind electrical outlets andswitch plates on exterior walls caulk and weather strip doors and windows caulk and seal leaks where plumbing, ducting orelectrical wiring penetrates through exterior walls, floors,and ceiling.
Upgrade ceiling insulations to R-36 (higher R valuesmean greater insulation levels and thus more energy savings)
Insulate exterior heated basement walls to at least R-11
Insulate floors over unheated areas to R-19
Install storm windows over single pane windows
Replace aging furnace, when needed, with an energyefficient model
Replace single pane windows with energy efficientdouble pane windows mounted in non-conducting windowframes

Cooling:

Open windows at night to bring in cool night air; closethem during the day
Close drapes during the day
Shade west facing windows
Draw cool night air into the house with a whole housefan
Use room air conditioning only where needed andinstall energy efficient models
Install a central system air conditioner only when wholehouse air condition is needed
Maintain an air conditioned house at 78 degrees F orhigher using a programmable thermostat to set thetemperature higher during the day when no one is home
Regularly change air conditioning system filters andclean the condenser
Plant deciduous shade trees on the west and southsides of your house

Hot Water:

Repair leaky faucets
Reduce the temperature setting of your water heater towarm (120 degrees F)
Install low-flow showerheads
Add an insulating blanket to your water heater
Wash clothes in warm or cold water using theappropriate water level setting for the load
Replace water heater, when needed, with an energyefficient model

ENERGY SAVING TIPS FOR HOMES PART2