Clase 7|| OFERTA SOLAR Y DEMANDA ENERGÉTICA

Energy Supply and Demand in Solar Installations

Introduction to Energy Supply and Demand

• The class focuses on energy supply and demand, crucial for sizing solar installations.

• Emphasis is placed on understanding energy demand from users who require electrical energy.

Solar Radiation in Peru

• Solar radiation varies across regions in Peru; the south receives more due to clearer skies.

• Understanding local solar radiation is essential for determining how much reaches the study area.

Calculating Energy Demand

• Identifying electrical equipment needs helps reduce electricity bills through solar technology.

• Knowledge of photovoltaic modules, charge regulators, inverters, and batteries is necessary for calculations.

Load Table and Energy Calculation

• A load table must be created by asking users about their equipment's power requirements.

• Total power consumption is calculated based on the number of devices and their operational hours.

Daily Energy Requirements

• Daily energy demands are calculated to align with available solar resources.

• An energy balance between harvested solar energy and user demand must be established.

System Types: Off-grid vs. On-grid

• Discussion includes off-grid systems that operate independently from the electric grid.

Understanding Hybrid Inverters and Energy Savings

Overview of Energy Metering

• The energy meter counts only the energy sourced from the grid, which is crucial for calculating savings.

• Increasing photovoltaic installation and inverter capacity can lead to more power entering homes, but caution is needed regarding low consumption and grid injection.

Differences Between Inverter Types

• A distinction exists between microinverters and hybrid inverters; the latter requires a battery input for backup capabilities.

• Microinverters are connected to the grid without battery support, while hybrid systems can operate independently with batteries.

Configurations and Future Trends

• Hybrid systems are evolving to function without strict dependence on the grid, allowing for isolated operation.

• Users can initially invest in modules and inverters before adding batteries later, promoting gradual independence from the grid.

Monitoring Consumption Effectively

• A device can be connected to monitor real-time household consumption, aiding in understanding energy usage patterns.

• Specific devices allow users to track peak consumption times effectively, especially useful for appliances like pumps that have variable loads.

Practical Applications of Monitoring Devices

• Bidirectional meters provide insights into both single-phase and three-phase systems, measuring current up to 500 amperes.

Understanding Solar Energy and Inverter Selection

The Role of Solar Energy in Electricity Charges

• Discussion on how electricity charges are based on energy rather than power or peak hours, indicating a need for clarity in understanding billing.

Evaluating Loads for Inverter Selection

• Importance of conducting a detailed load evaluation to determine the appropriate inverter size; reliance solely on load data can lead to incorrect specifications.

• Mention of peak loads and the necessity for accurate measurements to avoid underestimating inverter requirements.

Metering and Consumption Analysis

• Emphasis on using meters to accurately assess consumption patterns, which is crucial for determining device requirements without errors.

• Need for network analysis equipment if an existing installation is present; highlights the importance of understanding power behavior over time.

Planning New Installations

• For new constructions without electrical grids, it’s essential to survey expected usage patterns and operational times to ensure proper system design.

Pump Operation Considerations

• When integrating solar panels with pumps, it's critical to consider operational frequency (on/off cycles), as this impacts energy consumption significantly.

• Discussion about variators in pumping systems; their necessity depends on pump type and intended use (e.g., irrigation vs. domestic).

Pressure Systems in Water Supply

• Explanation of hydropneumatic tanks that maintain pressure by filling from a pump; these systems activate based on demand rather than continuous operation.

Addressing Pump Efficiency Issues

• Insight into how pump consumption relates more closely to operational time rather than just power ratings; emphasizes the role of tank sizing and sensor functionality in efficiency.

Constant Pressure Systems Explained

• Description of modern constant pressure systems used in buildings where pumps maintain water pressure across multiple floors without elevated tanks.

Monitoring Energy Consumption

Understanding Off-Grid Systems and Solar Radiation

Discussion on Off-Grid System Calculations

• The importance of considering peak energy usage during pump operation in off-grid systems is highlighted. Only average energy consumption may not suffice for accurate calculations.

• Confirmation that the upcoming calculations will incorporate these considerations, ensuring a comprehensive approach to energy assessment.

Overview of Solar Radiation Sources

• Transitioning to solar radiation sources, with a focus on photovoltaic (PV) systems as the primary topic of discussion. Acknowledgment that various countries, including Peru, have monitoring systems in place for solar data.

• Introduction of an interactive map displaying daily and monthly radiation data, which allows users to zoom in on specific locations for precise latitude and longitude readings.

Key Concepts in Solar Energy Calculation

• Emphasis on understanding peak sun hours as critical for calculating solar energy output; this involves multiplying photovoltaic power by these hours to determine total energy derived from solar sources.

• Explanation of irradiation versus irradiance: Irradiation refers to total energy received over time while irradiance measures power per unit area at a given moment. Standard conditions are defined as 1000 watts per square meter for peak sun hour calculations.

Determining Peak Sun Hours

• Peak sun hours are calculated based on daily irradiation data divided by standard conditions (1000 W/m²), providing insights into effective solar energy generation potential across different regions like Qatar and Australia, which exhibit varying averages around 6 to 7 peak sun hours annually.

• Monthly irradiation values are used in formulas to derive peak sun hours; this includes dividing monthly kilowatt-hour totals by the number of days in the month and standardizing against 1000 W/m² conditions. This method ensures accuracy in assessing solar potential throughout the year.

Practical Application: Case Study Analysis

• A practical example is introduced where participants will analyze radiation data specific to La Molina, Lima, using provided links for real-time analysis during the session. This hands-on approach aims to solidify understanding through application rather than theory alone.

Installation and Project Setup

Downloading Software

• The software is not free; users must enter a link to download the setup. Installation steps and tips for project setup have been provided.

Project Positioning

• The discussion involves positioning a project in an isolated area, specifically referencing Piura as a case study location.

Locating Coordinates

• Participants are asked to provide their location coordinates, focusing on identifying the Piura mill's position.

• There is difficulty in locating specific mills, with references made to Curumuy and surrounding areas.

Understanding Terrain Profile

Importance of Location

• Emphasis is placed on understanding the terrain profile, including latitude and orientation which are crucial for project evaluation.

Evaluating Latitude and Longitude

• The importance of latitude and longitude in determining project specifics is highlighted. Users are encouraged to save this information for future reference.

Calculating Optimal Angles

Using Google Tools

• Participants are instructed to use Google tools for calculating latitude and longitude, which will aid in determining optimal angles for their projects.

Angle Calculation Insights

• A formula emerges that calculates optimal angles based on latitude. This includes discussions about potential issues with data entry (e.g., commas vs. points).

Discussion on Formulas

Formula Clarification

• A formula related to optimal angle calculation is discussed, prompting questions from participants about its origin.

Request for Documentation

• Suggestions arise regarding creating a PDF document containing all relevant formulas to assist with Excel calculations.

Practical Application of Calculations

Sharing Resources

• An Excel file containing necessary calculations will be shared among participants for review and application in their projects.

Reiteration of Concepts

• Participants express uncertainty about previous lessons on optimal angle calculations, indicating a need for further explanation from the professor.

Optimal Inclination Angle Exercises

Example Calculations

• An example exercise prompts participants to calculate the optimal inclination angle using given formulas related to specific universities or locations.

Assumptions in Projects

Optimal Module Positioning and Calculations

Overview of Curriculum and Materials

• The discussion begins with a reference to the curriculum's advancement, specifically mentioning the optimal position of solar modules.

• Materials from previous classes are available on the platform, including resources on solar geometry and practical examples.

Importance of Calculations in Solar Installations

• The conversation highlights the distinction between theoretical calculations and real-world applications in solar installations.

• It is emphasized that commercial considerations often dictate installation practices over strict adherence to calculated formulas.

Optimal Orientation and Inclination

• The speaker discusses how optimal values for annual optical inclination can vary based on geographical location, particularly in Peru.

• Commercial structures typically come pre-set at angles like 15°, 21°, or 30°, which installers commonly use despite theoretical calculations suggesting different angles.

Practical Considerations for Installation

• Variability in structure design allows for slight adjustments in inclination; however, it is crucial to base these decisions on technical calculations.

• A specific formula referenced is found in bibliographic materials, indicating its importance as a reference point for installers.

Seasonal Adjustments and Cleaning Considerations

• The speaker notes that while calculations provide guidance, they do not dictate exact installation parameters; practical experience plays a significant role.

Understanding Solar Radiation and Installation Calculations

Overview of Solar Radiation Data

• The ideal solar radiation direction is towards the north, but practical conditions vary significantly.

• An average criterion is used to assess solar radiation; for instance, Lurín has a monthly radiation measurement of 118.98.

Calculation of Peak Sun Hours

• To estimate peak sun hours, divide the total irradiation data by a kilowatt (kW), resulting in kWh for standard conditions.

• Monthly data can be converted to daily averages by dividing by the number of days in January, yielding approximately 3.83 hours for Lima.

Impact of Angle of Inclination on Solar Harvesting

• Different angles of inclination affect solar energy collection; higher inclinations yield better results during winter months.

• In summer, a lower angle is preferred to maximize energy capture due to changes in sunlight exposure.

Evaluating Energy Needs and System Design

• When designing photovoltaic systems, consider using annual averages or minimum monthly data to ensure consistent energy availability.

• This approach may lead to increased costs but guarantees sufficient energy throughout the year.

Utilizing Technology for Site Analysis

• Google Earth can assist in identifying installation sites; users can pinpoint locations and analyze geographical features relevant to solar installations.

• Accurate measurements are crucial; understanding roof dimensions and orientation helps optimize panel placement.

Practical Considerations for Installation Space

• Determining the exact area available for installation involves measuring space accurately; this includes length and width specifications.

Project Orientation and Installation Planning

Overview of Project Setup

• The project is ready, with a screenshot provided for reference. It emphasizes the importance of not sharing this image publicly.

• The area for photovoltaic installation is defined, including a perimeter measurement of 200 m². Adjustments to color and opacity are suggested for better visibility in the project layout.

Cardinal Directions and Orientation

• Discussion on determining the project's orientation relative to cardinal points, specifically identifying north, south, east, and west based on geographical features like the sea.

• Clarification on how to visualize cardinal directions using natural indicators such as sunrise (east) and sunset (west), aiding in proper panel placement.

Panel Positioning Considerations

• Emphasis on accurately positioning solar panels according to north orientation; incorrect alignment can lead to inefficient energy capture.

• A visual demonstration shows that improper panel placement results in wasted space and reduced efficiency due to diagonal limitations.

Optimizing Space Utilization

• Recommendations for maximizing panel installation by adjusting their arrangement based on roof shape; optimal configurations allow for more panels without sacrificing performance.

• Discussion about potential adjustments when facing space limitations; strategic positioning can enhance energy output while accommodating existing structures.

Energy Consumption Patterns

• The importance of aligning panel orientation with user energy consumption patterns is highlighted. For instance, if peak usage occurs during afternoons, panels should be oriented towards the west.

• Acknowledgment that different users may have varying preferences based on their specific energy needs throughout the day; flexibility in design is crucial.

Challenges in Installation Design

• Addressing challenges related to limited space when installing solar systems; considerations must be made regarding available square meters versus desired power output.

Optimal Orientation and Angle for Solar Panels

Importance of Panel Orientation

• The orientation of solar panels is crucial; experience suggests that east-facing panels may be more effective in the morning, highlighting the need for a criterion based on practical experience.

• When considering space limitations (e.g., 200 m²), panel arrangement must adapt to fit within available area, which may require alternative orientations like east or west.

Space Limitations and Design Criteria

• The number of panels influences orientation decisions; fewer panels might allow for north-facing placement, while larger arrays necessitate different orientations based on spatial constraints.

• Space is often a limiting factor in solar panel installation, affecting optimal design choices.

Angle Considerations for Installation

• For Piura, an optimal angle of 7 degrees is suggested; however, adjustments (up to 15 degrees) may be necessary for self-cleaning and wind resistance considerations.

• Wind can impact panel stability; structures should be anchored at lower angles (5 degrees) if wind poses a threat.

Correction Factors in Calculations

• Environmental factors influence the assigned angle versus optimal angle; correction factors are essential to ensure accurate power delivery from solar panels under varying conditions.

• Radiation incidence depends on inclination angles; thus, calculations must consider both radiation data and the specific angle used during installation.

Data Analysis for Solar Supply

• Losses due to orientation angles are minimal when angles are low (e.g., -5 to -7 degrees); focus should shift towards inclination losses instead.

• To determine peak sun hours effectively, geographical data such as latitude and longitude must be accurately inputted into relevant tools or databases.

Monthly Irradiation Data Insights

• Monthly irradiation data from 2005 to 2015 provides insights into average peak sun hours necessary for system performance evaluation.

Data Analysis of Monthly and Annual Irradiation

Overview of Radiation Data

• The speaker introduces the data on annual and monthly irradiation, emphasizing that it is organized by month rather than year.

• It is noted that temperature will not be considered for an off-grid system, but it is acknowledged that temperature affects on-grid systems due to higher voltage connections.

Temperature Effects on Irradiation

• The discussion highlights how high temperatures can lead to lower voltage outputs in solar panels, particularly when many modules are connected in series.

• The impact of temperature on inverter operation is mentioned, indicating that excessive heat can cause operational issues.

Data Processing Steps

• The speaker outlines the process of organizing data from 2005 to 2016 into a structured format with months listed from January to December.

• Emphasis is placed on transferring and processing data accurately for detailed analysis by year, month, and season.

Average Monthly Irradiation Calculation

• A method for calculating average monthly irradiation based on the number of days in each month is discussed.

• Specific attention is given to determining the number of days in each month (e.g., January has 31 days, February has 28 or 29).

Peak Sun Hours Analysis

• The speaker explains how averages can be calculated using Excel to determine peak sun hours per year based on monthly irradiation values.

• There’s a focus on deriving daily averages from monthly data and understanding variations across different months.

Application for Client Understanding

• The importance of presenting this data clearly to clients or end-users is emphasized; it helps them understand their location's peak sunlight hours.

• Advanced software tools are mentioned as being more precise for project presentations involving radiation data but are beyond the scope of this course.

Understanding Solar Calculation in Project Proposals

Initial Technical Issues

• The speaker addresses a technical issue with hearing aids, indicating a need for adjustments to ensure clear communication during the session.

• After resolving the audio issues, the professor confirms that he can now hear and engage with the class.

Overview of Project Calculations

• The discussion revolves around outlining project calculations necessary for solar energy projects, emphasizing that this will be further explored in another course.

• The complexity of solar calculations is highlighted, particularly focusing on on-grid systems which were only partially covered in previous courses.

Practical Application of Solar Projects

• A specific example is provided regarding land use for photovoltaic parks, illustrating the broader implications and complexities involved in such projects.

• The importance of creating a technical economic proposal for users is stressed, along with understanding peak hours and software comparisons needed for accurate simulations.

Advanced Simulation Techniques

• The professor discusses advanced simulation techniques required for larger systems (100 kW or more), noting that specialized software like PVC is essential for these calculations.

• A question about seasonal radiation variations leads to insights on how different months affect solar panel efficiency and output.

Peak Sunlight Calculation Insights

• The conversation shifts to analyzing peak sunlight data across different months, identifying April as having higher radiation compared to June.

• Key values are derived from peak sunlight data; averages are calculated to inform decisions about panel numbers based on user needs and cost considerations.

User Consumption Analysis

• Discussion includes how user consumption patterns impact energy needs; an analysis of historical consumption reveals consistent monthly energy usage.

Photovoltaic Energy Consumption and Power Management

Overview of Photovoltaic Energy Pricing

• The discussion begins with the potential for photovoltaic energy to cover a significant percentage of annual consumption, emphasizing that monthly variations in usage do not pose major issues.

• A notable increase in energy costs is highlighted, with rates reaching 70 cents per kWh in 2023, reflecting a consistent upward trend.

Contracted Power and Usage

• The speaker discusses contracted power levels, mentioning specific locations like Lima and San Juan del Gancho where commercial energy consumption is calculated daily.

• It is explained that exceeding contracted power (e.g., 3 kW or 9 kW) can occur without immediate penalties unless it becomes a continuous issue; however, limitations are set by the installed switch capacity.

Understanding Power Profiles

• An analysis of power profiles reveals low energy consumption on weekends (Saturday and Sunday), suggesting inefficiencies if systems are oversized for these periods.

• The importance of accurately assessing equipment load and operational hours is emphasized for effective energy management in construction projects or existing setups.

Calculating Energy Needs

• A methodical approach using Excel is recommended for calculating total power demands based on technical specifications of consumer equipment such as TVs, refrigerators, and pumps.

• Peak power calculations are discussed, particularly how certain appliances (like pumps) may require additional consideration due to their higher starting demands compared to normal operating conditions.

Practical Considerations for Appliances

• Specific examples include discussing the wattage requirements for different types of pumps and the need to refer to technical sheets when selecting equipment like inverters.

Sizing and Calculation Review

Overview of Sizing Process

• The speaker introduces the topic of sizing, indicating that a formula will be shared for calculation purposes. An access link to this calculation will be provided for students to view and download.

• The speaker emphasizes the importance of tracking progress in Excel, stating that updates will always be available on a shared drive for students to reference.