Lightning Protection System

LIGHTNING PROTECTION SYSTEM (LPS)

Lightning system used in Malaysia can be divided into 2 category which is conventional lightning system and unconventional lightning system.

·         Conventional lightning system

-          known as a standard LPS.

-          It comply with the technical standards and codes of practice.

Source:Google Images

·         Unconventional lightning system

-          It known as a system that not comply with the standard technical practice.

-          It also more cheaper than the conventional system.

-          Accident will be easily occur by using this system.

 

Source:Google Images

The Components of the lightning system

 

Source:Google Images

Damages by Lightning

There are many accident occur because of getting hit by lightning. It normally are happen at the upper part of the structure. For example:

Ø  it pointed apex roofs, spires and protrusions

Ø  also to the gable roof ends and outer roof corners.

Basic Principle of Lightning Rod

A lightning rod or lightning conductor is a metal rod mounted on a structure and intended to protect the structure from a lightning strike. It consisted of a pointed metal pole, extending upward above the building. The conducting rod is attached by a copper cable to a grounding rod which is buried in Earth below.

            As lightning hits the structure, instead of passing through the structure, it will strike the rod and conducted to ground through a wire. If not, it could cause fire or electrocution.Intense electric fields surrounding a pointed object serve to ionize the surrounding air, thus enhancing its conductive ability. As a storm cloud approaches, there is a conductive pathway established between statically charged cloud and the lightning rod. Static charges gradually migrate along this pathway to the ground, thus reducing the likelihood of sudden and explosive discharge. Therefore, the primary role of a lightning rod is to discharge the cloud over a onger length of time, thus preventing the excessive charge build up which is characteristic of a lightning strike.

When there is positive charges in the ground, the copper rod acts as perfect conductor and direct the charges into lightning rod.

Storm cloud carrying concentrated negative charge will hit the positive charges (lightning rod).

As the lightning rod charges take place, it will safely conduct back to ground (Earth) safely.

The function of lightning rod is not to attract lightning, but to provide path least resistance for lightning to safely travel to the ground.

Earth Protection System

Factors that should be incorporated when selecting an earth protection system for a building include:

1. The contents of the building and any personnel that may be working inside.
2. The risk posed by a full lightning strike and the full lightning electromagnetic field.
3. Requirements for emergency protection device.
4. Any of the buildings natural components that can be considered as part of the lightning protection system.
5. The four key components of the lightning protection system are: Roof termination system, down conductor configuration, earth termination network, bonding.

External Lightning Protection System

Source : Google Images

The function is to protect buildings from direct lightning strikes, potential fire as well as the effects of injected lightning currents (non-incentive flash). As well as it was external protection, so the building area that need protection include the various systems used to cover the structures or buildings, as well as open and people against direct lightning strikes areas. It consists of air-termination systems, down conductors and an earth-termination system as shown above. 

Air termination Systems

• Located over the highest points of the building to intercept lightning stroke s before they strike the fabric itself. 
• A single point air terminatiom is considered to give a zone of protection defined by a cone,; the apex of the cone is formed by the air termination and the base of the cone has a radius equal to the height of the air termination. 
• The probability of structure penetration by a lightning current is considerably decreased by the presence of a properly designed air - termination system. 
• Air termination systems can be composed of any combination of the following elements : - rods (including free-standing masts); catenary wires; and meshed conductors. 
• Positioning : - Air termination components installed on a structure shall be located at corners, exposed points and edges (especially on the upper level of any facades) in accordance with one or more of the following methods 
• the  rolling sphere method 

• the mesh method

• the protection angle method

Down-conductor Systems

In order to reduce the probability of damage due to lightning current flowing in the LPS, the down-conductors shall be arranged in such a way that from the point of strike to earth: -

• several parallel current path exist
• the length of the current paths is kept to a minimum
• equip potential bonding to conducting parts of the structure is performed according to the requirements.
• the down-conductors shall be installed straight and vertical such that they provide the shortest and most direct path to earth. the formation of loops shall be avoided.
• down-conductors shall not be installed in gutters or down-spouts even if they are covered by insulating material.

Earth-termination System

• To disperse the lightning current into the mass of the earth.
• To reduce any potentially dangerous over voltages.
• In general, an earthing below 10 ohms, measured at low frequency is recommended
• single integrated structure earth-termination system is preferable and is suitable for all purposes such as lightning protection, power systems, and telecommunication systems.

For earth-termination systems, two basic types of earth electrode arrangements apply:

1. Type 'A' arrangement
2. Type 'B' arrangement

Solar System

SOLAR ENERGY

                           













Solar energy is the energy obtained by capturing heat and light from the Sun. The energy that solar panel collect from the Sun is called as a Solar Energy. Solar energy is often known as a large blue or black solar panels on rooftops or portable highway signs that have a small panel attached. These solar panels, also known as photo voltaic modules (or PV modules), convert sunlight into electricity, and they have been the backbone of renewable energy for decades. 

Here is the new product of solar panel.

Source : Google Images

Active Solar System is similar to passive solar system. It collect solar heat and convert into water or in fluid form. A solar hot water production system is consists of:

•  solar flat plate collectors, 
• heat storage vessel and
•  piping. 

Source: Google Images

                          The plate collector absorb heat from solar radiation and transferred into storage vessel. Active solar energy can be use for household use and anywhere low temperature where heat is needed.

Passive Solar Energy

Passive solar energy is an energy that collect from sunlight and direct use for lighting, heating, ventilation and other purpose. For this type of solar energy, the house will act as a solar collector and storage facility. It no need use any of the pump and fans. This system used to store and absorb the heat from the sun.

It has divide into 3 types which is attached greenhouse, direct-gain and indirect-gain.

·         Direct-gain

Ø  This direct-gain is a system which the heat collection, storage and distribution all occur in the same space.

Ø  Solar will pass through window into the room.

Ø  Thermal mass used to absorb the radiation.

Ø  Absorbed heat is radiated back into the living space at night.

Source: Google Images

·         Indirect-gain

Ø  A system that collects and stores the energy in one part of the structure and uses natural heat transfer to distribute the heat to other structure.

Ø  It normally use Trombe Wall which is a massive black masonry that acts as a solar collector and heat storage medium.

Source: Google Images

·         Attached greenhouse

Source: Google Images

Ø  Which is a combination of direct and indirect-gain system.

Ø  It used water drums and masonry floor as heat storage in the attached greenhouse.

How electricity generated? 

Photovoltaic method 

Photovoltaics (PV) is a term which covers the conversion of light into electricity using semiconducting materials that exhibit the photovoltaic effect, a phenomenon studied in physics, photochemistry, and electrochemistry.
A typical photovoltaic system employs solar panels, each comprising a number of solar cells, which generate electrical power. PV installations may be ground-mounted, rooftop mounted or wall mounted. The mount may be fixed, or use a solar tracker to follow the sun across the sky.

Solar thermal energy / Concontrated solar power 

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 or powers a thermochemical reaction. 

Technologies 

•  Parabolic trough
• A parabolic trough consists of a linear parabolic reflector that concentrates light onto a receiver positioned along the reflector's focal line.
• The receiver is a tube positioned directly above the middle of the parabolic mirror and filled with a working fluid. 
• The reflector follows the sun during the daylight hours by tracking along a single axis. 
• A working fluid (e.g. molten salt) is heated to 150–350 °C (302–662 °F) as it flows through the receiver and is then used as a heat source for a power generation system.

• Solar power tower
• A solar power tower uses an array of tracking refelctors to concentrare light on a central receiver atop a tower. 
• Power towers are more cost effective, offer higher effciency and better energy storage capability among CSP techonologies. 

• Stiring Solar dish 
• A dish Stirling or dish engine system consists of a stand-alone parabolic reflector that concentrates light onto a receiver positioned at the reflector's focal point. The reflector tracks the Sun along two axes. The working fluid in the receiver is heated to 250–700 °C (482–1,292 °F) and then used by a Stirling engine to generate power.
• Parabolic-dish systems provide high solar-to-electric efficiency (between 31% and 32%), and their modular nature provides scalability.

• Fresnel reflectors
• Fresnel reflectors are made of many thin, flat mirror strips to concentrate sunlight onto tubes through which working fluid is pumped. Flat mirrors allow more reflective surface in the same amount of space than a parabolic reflector, thus capturing more of the available sunlight, and they are much cheaper than parabolic reflectors. Fresnel reflectors can be used in various size CSPs.

Gas Supply System

What is Gas ?

• Gas is one of is one of is one of the four fundamental states of matters (the others being (the others being solid, solid, liquid, liquid, liquid, and plasma). 
• A pure gas may be made up of individual atoms (e.g. a noble gas like neon), elemental molecules made from one type of atom (e.g. oxygen), or compound molecules made from a variety of atoms (e.g. carbon dioxide). 
• A gas mixture would contain a variety of pure gases much like the air.
• What distinguishes a gas from liquids and solids is the vast separation of the individual gas particles.This separation usually makes a colorless gas invisible to the human observer.
• One type of commonly known gas is steam. 

Gas Law

Boyle’s Law                                                                                                   

    

Boyle's law (sometimes referred to as the Boyle–Mariotte law, or Mariotte's law^[1]) is an experimental gas law that describes how the pressure of a gas tends to increase as the volume of the container decreases. An increase in pressure causes a gas to contract. A decrease in pressure causes a gas to expand.

Pressure is directly proportional to the reciprocal of volume

       or

${\displaystyle PV=k}$

Pressure multiplied by volume equals some constant ${\displaystyle k}$.

Charles’ Law

Charles's law (also known as the law of volumes) is an experimental gas law that describes how gases tend to expand when heated. A modern statement of Charles's law is:

When the pressure on a sample of a dry gas is held constant, the Kelvin temperature and the volume will be directly related.

This directly proportional relationship can be written as:

${\displaystyle V\propto T}$ or  

where:

V is the volume of the gas,

T is the temperature of the gas (measured in kelvins),

k is a constant.

Natural Gas

What is natural gas ?

Natural gas occurs deep beneath the earth's surface. Natural gas consists mainly of methane, a compound with one carbon atom and four hydrogen atoms. Natural gas also contains small amounts of  hydrocarbon gases liquids and non-hydrocarbon gases. We use natural gas as a fuel and to make materials and chemicals.

How did natural gas form?

Millions of years ago, the remains of plants and animals (diatoms) decayed and built up in thick layers, sometimes mixed with sand and silt. Over time, these layers were buried under sand, silt, and rock. Pressure and heat changed some of this organic material into coal, some into oil (petroleum), and some into natural gas. In some places, the natural gas moved into large cracks and spaces between layers of overlying rock. In other places, natural gas occurs in the tiny pores (spaces) within some formations of shale, sandstone, and other types of sedimentary rock, where it is referred to as shale gas or tight gas. Natural gas also occurs in coal deposits, which is called coalbed methane.

Use of natural gas 

• Natural gas is a fossil fuel used as a source of energy for heating, cooking, and electricity generation. 
• It is also used as a fuel for vehicles and as a chemical feedstock in the manufacture of plastics and other commercially important organic chemicals. 
• Fossil fuel based natural gas is a non-renewable resource.

Natural Gas Processing

Peninsular gas utilisation (PGU)

This natural gas transmission pipeline serves as the backbone of Peninsular Malaysia’ natural gas supply infrastructure.

• The pipelines are operated and maintained by PETRONAS GAS BERHAD (PGB).
• This PGU infrastructure comprises six gas processing plants with a capacity of 2000 million standard cubic feet per day.
• The maintenance activities of the transmission pipeline are carried out in the stipulated region along the four phases through the Pipeline Integrity Management System (PIMS) programs

Distribution pipeline

A distribution pipeline supplies and distributes the natural gas from the city gate station to the end-users.

Normally, the pressure of the natural gas would be reduce and the gas is odorized for safety purpose at the city gate station.

LPG Piping System

Liquid Petroleum Gas is flammable mixtures of hydrocarbon gases used in heating appliances. LPG is produced from refining petroleum crude oils process. It is stored as a liquid under pressure. In natural state, LPG is odourless and odourless. LPG may flow along the ground and into drains and be ignited at a distance from source of leakage. This is because LPG vapour is heavier than air.

LPG Piping System consists of two main components:

1.     1.  Storage Vessel

·         It is stored at consumer’s premises in pressurised vessels (for bulk storage systems) or in cylinders, which are stored in multiples

·         Design pressure of the vessel is usually 1725kPa

·         It could be installed :

i.   Above ground

ii.  Underground

iii.  Mounded (tank totally covered by earth above the ground)

.      2. Delivery/Service Pipeline

·         It is used for delivering  the LPG vapour from the storage tank to appliances

LPG Supply Concept

  Gas PipeShaft/Duct

Purpose:

·         Early detection of gas leakage

·         Prevent dangerous accumulation

·         Access for maintenance

            Gas pipe installation must follow “Guidelines on Domestic Gas Piping System” by Suruhanjaya Tenaga.

Gas pipe within building should be run exposed. Areas where the riser passes also should be well ventilated. Where a gas riser is to be located in a pipe shaft, permanent ventilation should be provided outside the building. Continuous shaft, ventilation can be provided by provision of openings at top and bottom to the outdoors. Entering riser pipes from shaft or duct should be fire stopped.


Fire Stopper Material  

Fire Stopping is sealing product that take up imperfections of fit or design tolerate between the fire resisting fixed elements of the building to restrict the passage of fire and smoke. 
  
The important of Fire Stopping Material is :

• For early detection of gas leakage
• Prevent dangerous gas accumulation
• Access for maintenance  

Source: Google Images

The popular material that been used for fire stopping is Yeast. The yeast that people usually used for bake a bread. Yeast is the best gas safety. 

Source: Google Images