Central receiver power systems use a large field of mirrors called heliostats to reflect sunlight to a central receiver tower. The concentrated sunlight is used to heat a working fluid like water/steam to high temperatures, which is then used to drive a turbine and generate electricity. A central receiver power plant in California demonstrated this technology, using over 1800 heliostats covering 72 acres to produce steam at 516°C and generate up to 42 MW of power. Central receiver systems can achieve high operating temperatures above 600°C, have good potential for thermal energy storage, and have been commercially demonstrated. However, they also have drawbacks like high construction costs and requiring significant land area.
Solar thermal power generation systems use mirrors to collect sunlight and produce steam by solar heat to drive turbines for generating power. This system generates power by rotating turbines like thermal and nuclear power plants, and therefore, is suitable for large-scale power generation.
Solar collector : A device designed to absorb incident solar radiation and to transfer the energy to a fluid passing in contact with it, usually liquid or air.
Flat – Plate Collector : A typical flat-plate collector is an insulated metal box with a glass or plastic cover (called the glazing) and a dark-colored absorber plate. These collectors heat liquid or air at temperatures less than 180°F.
Solar collector ppt by Vivek Atalkar.
A solar collector is a device that collects and/or concentrates solar radiation from the Sun. These devices are primarily used for active solar heating and allow for the heating of water for personal use.
Classification of Solar collector
Flat Plate collector
Photovoltaic Power Conversion systems
Solar constant:
Pyranometer:
Solar Photovoltaic(SPV) systems
Construction of Solar Cell
I-V curve and PV curve of solar cell
Efficiency of Solar Panel
Effect of Dust On Performance Of Solar PV Panel
Effect of temperature on solar power panel efficiency
Solar Photovoltaic(SPV) systems
A flywheel, in essence is a mechanical battery - simply a mass rotating about an axis.Flywheels store energy mechanically in the form of kinetic energy.They take an electrical input to accelerate the rotor up to speed by using the built-in motor, and return the electrical energy by using this same motor as a generator.Flywheels are one of the most promising technologies for replacing conventional lead acid batteries as energy storage systems.
Solar Energy Storage:-
Methods of storage such as sensible, latent heat &
thermochemical storage,selection of method of storage,
properties of storage materials and different arrangements of
storages
Solar thermal power generation systems use mirrors to collect sunlight and produce steam by solar heat to drive turbines for generating power. This system generates power by rotating turbines like thermal and nuclear power plants, and therefore, is suitable for large-scale power generation.
Solar collector : A device designed to absorb incident solar radiation and to transfer the energy to a fluid passing in contact with it, usually liquid or air.
Flat – Plate Collector : A typical flat-plate collector is an insulated metal box with a glass or plastic cover (called the glazing) and a dark-colored absorber plate. These collectors heat liquid or air at temperatures less than 180°F.
Solar collector ppt by Vivek Atalkar.
A solar collector is a device that collects and/or concentrates solar radiation from the Sun. These devices are primarily used for active solar heating and allow for the heating of water for personal use.
Classification of Solar collector
Flat Plate collector
Photovoltaic Power Conversion systems
Solar constant:
Pyranometer:
Solar Photovoltaic(SPV) systems
Construction of Solar Cell
I-V curve and PV curve of solar cell
Efficiency of Solar Panel
Effect of Dust On Performance Of Solar PV Panel
Effect of temperature on solar power panel efficiency
Solar Photovoltaic(SPV) systems
A flywheel, in essence is a mechanical battery - simply a mass rotating about an axis.Flywheels store energy mechanically in the form of kinetic energy.They take an electrical input to accelerate the rotor up to speed by using the built-in motor, and return the electrical energy by using this same motor as a generator.Flywheels are one of the most promising technologies for replacing conventional lead acid batteries as energy storage systems.
Solar Energy Storage:-
Methods of storage such as sensible, latent heat &
thermochemical storage,selection of method of storage,
properties of storage materials and different arrangements of
storages
Concentrated solar power (also called concentrating solar power, concentrated solar thermal, and CSP) systems generate solar power by using mirrors or lenses to concentrate a large area of sunlight, or solar thermal energy, onto a small area. Electricity is generated when the concentrated light is converted to heat, which drives a heat engine (usually a steam turbine) connected to an electrical power generator.
Introduction to solar thermal system
Working of solar thermal system
Solar collector
Type of solar collector
Solar water heater
Solar heating and cooling
Solar refrigeration and air conditioning
Advantage and Disadvantages
State of ICS and IoT Cyber Threat Landscape Report 2024 previewPrayukth K V
The IoT and OT threat landscape report has been prepared by the Threat Research Team at Sectrio using data from Sectrio, cyber threat intelligence farming facilities spread across over 85 cities around the world. In addition, Sectrio also runs AI-based advanced threat and payload engagement facilities that serve as sinks to attract and engage sophisticated threat actors, and newer malware including new variants and latent threats that are at an earlier stage of development.
The latest edition of the OT/ICS and IoT security Threat Landscape Report 2024 also covers:
State of global ICS asset and network exposure
Sectoral targets and attacks as well as the cost of ransom
Global APT activity, AI usage, actor and tactic profiles, and implications
Rise in volumes of AI-powered cyberattacks
Major cyber events in 2024
Malware and malicious payload trends
Cyberattack types and targets
Vulnerability exploit attempts on CVEs
Attacks on counties – USA
Expansion of bot farms – how, where, and why
In-depth analysis of the cyber threat landscape across North America, South America, Europe, APAC, and the Middle East
Why are attacks on smart factories rising?
Cyber risk predictions
Axis of attacks – Europe
Systemic attacks in the Middle East
Download the full report from here:
https://sectrio.com/resources/ot-threat-landscape-reports/sectrio-releases-ot-ics-and-iot-security-threat-landscape-report-2024/
"Impact of front-end architecture on development cost", Viktor TurskyiFwdays
I have heard many times that architecture is not important for the front-end. Also, many times I have seen how developers implement features on the front-end just following the standard rules for a framework and think that this is enough to successfully launch the project, and then the project fails. How to prevent this and what approach to choose? I have launched dozens of complex projects and during the talk we will analyze which approaches have worked for me and which have not.
Key Trends Shaping the Future of Infrastructure.pdfCheryl Hung
Keynote at DIGIT West Expo, Glasgow on 29 May 2024.
Cheryl Hung, ochery.com
Sr Director, Infrastructure Ecosystem, Arm.
The key trends across hardware, cloud and open-source; exploring how these areas are likely to mature and develop over the short and long-term, and then considering how organisations can position themselves to adapt and thrive.
PHP Frameworks: I want to break free (IPC Berlin 2024)Ralf Eggert
In this presentation, we examine the challenges and limitations of relying too heavily on PHP frameworks in web development. We discuss the history of PHP and its frameworks to understand how this dependence has evolved. The focus will be on providing concrete tips and strategies to reduce reliance on these frameworks, based on real-world examples and practical considerations. The goal is to equip developers with the skills and knowledge to create more flexible and future-proof web applications. We'll explore the importance of maintaining autonomy in a rapidly changing tech landscape and how to make informed decisions in PHP development.
This talk is aimed at encouraging a more independent approach to using PHP frameworks, moving towards a more flexible and future-proof approach to PHP development.
Epistemic Interaction - tuning interfaces to provide information for AI supportAlan Dix
Paper presented at SYNERGY workshop at AVI 2024, Genoa, Italy. 3rd June 2024
https://alandix.com/academic/papers/synergy2024-epistemic/
As machine learning integrates deeper into human-computer interactions, the concept of epistemic interaction emerges, aiming to refine these interactions to enhance system adaptability. This approach encourages minor, intentional adjustments in user behaviour to enrich the data available for system learning. This paper introduces epistemic interaction within the context of human-system communication, illustrating how deliberate interaction design can improve system understanding and adaptation. Through concrete examples, we demonstrate the potential of epistemic interaction to significantly advance human-computer interaction by leveraging intuitive human communication strategies to inform system design and functionality, offering a novel pathway for enriching user-system engagements.
Search and Society: Reimagining Information Access for Radical FuturesBhaskar Mitra
The field of Information retrieval (IR) is currently undergoing a transformative shift, at least partly due to the emerging applications of generative AI to information access. In this talk, we will deliberate on the sociotechnical implications of generative AI for information access. We will argue that there is both a critical necessity and an exciting opportunity for the IR community to re-center our research agendas on societal needs while dismantling the artificial separation between the work on fairness, accountability, transparency, and ethics in IR and the rest of IR research. Instead of adopting a reactionary strategy of trying to mitigate potential social harms from emerging technologies, the community should aim to proactively set the research agenda for the kinds of systems we should build inspired by diverse explicitly stated sociotechnical imaginaries. The sociotechnical imaginaries that underpin the design and development of information access technologies needs to be explicitly articulated, and we need to develop theories of change in context of these diverse perspectives. Our guiding future imaginaries must be informed by other academic fields, such as democratic theory and critical theory, and should be co-developed with social science scholars, legal scholars, civil rights and social justice activists, and artists, among others.
GraphRAG is All You need? LLM & Knowledge GraphGuy Korland
Guy Korland, CEO and Co-founder of FalkorDB, will review two articles on the integration of language models with knowledge graphs.
1. Unifying Large Language Models and Knowledge Graphs: A Roadmap.
https://arxiv.org/abs/2306.08302
2. Microsoft Research's GraphRAG paper and a review paper on various uses of knowledge graphs:
https://www.microsoft.com/en-us/research/blog/graphrag-unlocking-llm-discovery-on-narrative-private-data/
2. Concentrating Solar
Technologies
Low Temperature
(<100°C)
Flat Plate
Collectors
Solar Chimney
Solar Pond
High Temperature-
Point Focusing
(>400°C)
Central Receiver
System
Parabolic Dish
Medium Temperature – Line
Focusing (≈ 400°C)
Parabolic
Trough
Fresnel
Collectors
3. INTRODUCTION
Solar thermal power is relatively new technology which has already shown enormous promise and take
the global challenges of clean energy, climate change and sustainable development.
The CENTRAL RECEIVER concept for solar energy concentration and collection is based on a field of
heliostats that reflect the incident sunshine to a receiver (boiler) at the top of a centrally located tower.
Solar energy to be collected in the entire field, is transmitted optically to a small central collection region.
Typically 80-95% of the reflected energy is absorbed into the working fluid
which is pumped up the tower and into the receiver. The heated fluid (or steam) returns down the tower
and then to a thermal demand such as a thermo electrical power plant or an industrial process requiring
heat.
Central receiver technology for generating electricity has been demonstrated in the Solar One pilot power
plant at Barstow, California. This system consists of 1818 heliostats, each with a reflective area of 39.9
m2(430 ft2) covering 291,000 m2(72 acres) of land. The receiver is located at the top of a 90.8 m (298 ft.)
high tower and produces steam at 516°C (960°F) at a maximum rate of 42 MW.
4. CRPS Characteristics
Temp 600-800°C
Point Focusing
Flat Mirrors(slightly concave)
Commercially proven
Central Receiver tower
Heat Storage capability
Feasible on Non Flat sites
Good performance for large capacity &
temperatures
5. • Solar thermal power generation
systems use mirrors to collect
sunlight and produce steam by solar
heat to drive turbines for generating
power.
• For steam as a working fluid, the
working and plant description is
displayed in figure.
• Power conversion cycle used:
Rankine cycle (steam turbine)
Brayton cycle (gas turbine)
Combined cycle (gas turbine + steam
turbine)
Stirling engines
6. SYSTEM DESCRIPTION
The major components of central receiver power
system are:
Heliostat
Tower/ receiver
Working fluid
Storage tanks
Generator
7. It is an instrument consisting of mirrors mounted on an axis moved by clockwork by which a sunbeam is
steadily reflected in one direction.
The thin glass mirrors are supported by a substrate backing to form a slightly concave mirror surface.
The reflected surface is mounted or supported on a pedestal that permits movement about the azimuth and
elevation axis..
Another heliostat design concept, not so widely developed, uses a thin reflective plastic membrane
stretched over a hoop.
Reflectivity of a new, clean mirror ≈ 0.90 - 0.94
CONSIDERATIONS FOR HELIOSTATS:-
1. DESIGN CONSIDERATION (reflectivity, back support structure, elevation drive, azimuth drive, pedestal,
spacing etc.)
2. HELIOSTAT ERRORS (shading and blocking error, cosine efficiency loss)
3. ENVIRONMENTAL CONSIDERATIONS (wind speed, dust on mirror)
4. TRACKING AND POSITIONING
HELIOSTATS
10. Receiver-Tower
Function
The receiver, placed at the top of a tower, is located at a point where reflected energy
from the heliostats can be intercepted most efficiently.
The receiver absorbs the energy being reflected from the heliostat field
and transfers it into a heat transfer fluid.
Components:
• Tower
• Absorber
• Supporting structure
• Other auxiliary elements: steam drum, recirculation pumps…)
Receiver system
Function
Components
Types of receivers
Working fluids
11. Types of receiver:
• Cavity receiver:
• External receiver :
(Cylindrical type)
In this receiver flux absorbing surface is
placed inside a insulating cavity to
reduce the convective losses
13. Cosine factor
The efficiency depends on both the sun’s position and the location
of the individual heliostat relative to the receiver.
where α and A are the sun’s altitude and azimuth angles, respectively, and z, e, and n
are the orthogonal coordinates from a point on the tower at the height of the
heliostat mirrors.
Yearly average cosine factor for a north heliostat field is 0.71 – 0.91
14. Shading and blocking
Shadowing occurs at low sun angles when a heliostat casts its shadow on a heliostat
located behind it. Therefore, not all the incident solar flux is reaching the reflector.
Blocking occurs when a heliostat in front of another heliostat blocks the reflected flux
on its way to the receiver.
The amount of shadowing and blocking in a particular field layout is a function of the
heliostat spacing, tower height, and sun angle
Shading
Blocking
15. Air transmittance
Atmospheric transmittance has been approximated by Vittitoe and Biggs (1978)
for a clear day
for 23 km visibility
where S is the slant range from heliostat to receiver in kilometres
for 5 km visibility
16. Field losses:-
the energy losses associated specifically with the heliostat field include four and the
five greatest sources of the energy loss.
Followinf are the field losses:
• cosine
• Shadowing and blocking
• Reflectance
• Attenuation – It is third most important loss factor
where ηcos, ηshadow, ηblock, ηrefl and ηatten are efficiencies based
on cosine, shadowing, blocking, mirror reflectance and atmospheric
attenuation respectively.
17. Receiver losses:-
Following are the receiver loss factor:
• Spillage
• Absorptance
• Radiation
• Convection and conduction
where ηreceiver, ηspill, ηabsor, ηrad, ηconvec, ηcond are efficiencies
based on spillage, absorptance, radiation, convection and
conduction respectively.
18. CRS
η ≈ 50 – 60 %
Input power
DNI * mirror area
Net thermal output (η ≈ 50 – 60 %)
Efficiency of central receiver power system
19. Working fluids:
Good thermal characteristics: thermal capacity, phase-change enthalpy,
state at air temperature
Non-corrosive, non- Toxic, Non-Flammable
Inexpensive, abundant
Working fluids for CRS:
Water/Steam
saturated steam
superheated steam
Molten salts
Air
pressurized
atmospheric
Sodium
Thermal oils
23. Advantage and Disadvantage of CRS:
Advantages:
• Ability to achieve high temperature
• Renewable. No fuels required.
• Can utilize thermal storage to better match supply with demand
• Operating costs are low
• Multiple thermal energy storage options
• High potential for improved efficiency or cost reduction
Disadvantages:
• Complexity
• Construction/installation costs can be high
• They require a considerable amount of space
• Slightly more expensive than solar PV
• Low energy density
25. Earth receives around 174 Petawatts of energy from sun and only a
small part of it is sufficient to meet the annual world electricity
consumption of 20 Trillion kWh
We Just need to tap this potential
Thank You