Kalugu

Insight into South Asia

Nuclear Power Up-rate will aid growth to world Power generation

As the global economic slow down hist hard on several sectors of the once thriving power industry, the utilities segment is now striving to find innovative ways to enhance their plants operating capacity. Several US based nuclear plants are in the process of modifying their existing fleet to achieve enahnced output. This may turn out to be a boon for South Asia and other similar the power hungry plants wordlwide.
Power up-rate in simple terms is the process of increasing the power output of a running plant by enabling modification to existing components. Since up-rate of existing plants require less investment & little down time, many more utilities are submitting their desire to NRC (Nuclear Regulatory Commission, USA). When the NRC issues a license for a commercial nuclear power plant, the agency sets limits on the maximum heat output, or power level, for the reactor core. This power level dictates a significant role in many of the analyses that demonstrate plant safety, so the NRC’s authorization is required before a plant can change its maximum power level. Power up-rate only occurs after the NRC approves a commercial nuclear power plant’s request to augment its power.
To increase the power output of a reactor, more highly enriched uranium fuel and/or more fresh fuel is required. This enables the reactor to produce extra thermal (Heat) energy and therefore additional steam, driving a turbine generator to produce more electricity.
Types of Power Up-rates:
The design of every commercial reactor has excess capacity needed to potentially allow for an up-rate, which can fall into one of three categories:
a) Measurement uncertainty recapture power up-rates
b) Stretch power up-rates
c) Extended power up-rates.
a) Measurement uncertainty recapture {MUR} power up-rates are power increases less than 2 % of the approved power level, and are achieved by implementing superior techniques for calculating reactor power. This involves the use of high-tech devices to more accurately measure feed water flow which is used to calculate reactor power.
b) Stretch power up-rates {SPU} are classically between 2 % and 7 %, with the actual increase in power depending on a plant design’s specific operating margin. These involve, modest equipment replacement and little or no change to either the nuclear steam supply system {Reactor – Boiler} or turbine by limiting increase in pressure (2% to 3%) to allow sufficient mass flow margin in the high-pressure {HP} turbine. Stretch power up-rates usually involve changes to instrumentation settings but do not involve major plant modifications.
c) Extended power up-rates are greater than stretch power up-rates and EPU increases the original licensed thermal power output by up to 20%. Extended power up-rates usually require significant modifications to major pieces of non-nuclear equipment such as high-pressure turbines, Feed water heaters, condensate extraction pumps, Drain pumps, Feed pumps and motors, main generators, and/or transformers.
Expected Applications for Power Up-rates:
The following information is based on the October 2008 survey of NRC licensees. Survey indicate utilities plan to submit 42 power up-rate applications in the next five years, including 21 extended power up-rates, 1 stretch power up-rates and 20 measurement uncertainty recapture up-rates. If these applications are permitted, the resulting up-rates would add another 8,683 MWt (2,894 MWe) to America’s power generating capacity.
Many Economic Returns:
There are also other benefits associated with an up-rate. Many of the existing nuclear plants have been operating for 30 years or more and require some kind of retrofits and modifications on major equipments. These and other potential plants have either completed or looking for a license renewal. Combining an up-rate with a maintenance upgrade or license extension allows some of the cost to be shared among these programs. Also utility doesn’t have to wait as long to collect the benefits of an EPU (Extended Power Uprate). An EPU can be brought into operation in about half the time required to license and build a new plant.
More than Replacing Components:
The success of an EPU program heavily relies on the quality of the management team, their ability to develop an effective execution plan, to schedule the work efficiently and to build valuable controls to ensure that those schedules are carried out.
It is difficult to generalize the perfect plan to complete an EPU for a given plant. Difference between previous modifications and equipment change outs to maintain plant operation all combine to make the EPU program for each nuclear plant unique.
With coal, oil and gas-fired power plants increasing coming under criticism for damaging the environment, Nuclear energy will pave the way to an important electric power generation platform for the future.

As the global economic slow down hits hard on several sectors of the once thriving power industry, the utilities segment is now striving to find innovative ways to enhance their plants operating capacity. Several US based nuclear plants are in the process of modifying their existing fleet to achieve enhanced output. While these initiatives will increase USA’s power output, can very well be implemented in South Asia to deliver similar results. The knowledge on these procedures can be valuable for all power plants across the globe.

Power up-rate in simple terms is the process of increasing the power output of a running plant by enabling modification to existing components. Since up-rate of existing plants require less investment & little down time, many more utilities are submitting their desire to NRC (Nuclear Regulatory Commission, USA). When the NRC issues a license for a commercial nuclear power plant, the agency sets limits on the maximum heat output, or power level, for the reactor core. This power level dictates a significant role in many of the analyses that demonstrate plant safety, so the NRC’s authorization is required before a plant can change its maximum power level. Power up-rate only occurs after the NRC approves a commercial nuclear power plant’s request to augment its power.

The Beaver Valley nuclear power plant, USA. Almost half of American reactors have undergone  maintenance to boost performance, often carried out alongside work to extend the reactors working lives.

The Beaver Valley nuclear power plant, USA. Almost half of American reactors have undergone maintenance to boost performance, often carried out alongside work to extend the reactors' working lives.

To increase the power output of a reactor, more highly enriched uranium fuel and/or more fresh fuel is required. This enables the reactor to produce extra thermal (Heat) energy and therefore additional steam, driving a turbine generator to produce more electricity.

Types of Power Up-rates:

The design of every commercial reactor has excess capacity needed to potentially allow for an up-rate, which can fall into one of three categories:

a) Measurement uncertainty recapture power up-rates

b) Stretch power up-rates

c) Extended power up-rates.

a) Measurement uncertainty recapture {MUR} power up-rates are power increases less than 2 % of the approved power level, and are achieved by implementing superior techniques for calculating reactor power. This involves the use of high-tech devices to more accurately measure feed water flow which is used to calculate reactor power.

b) Stretch power up-rates {SPU} are classically between 2 % and 7 %, with the actual increase in power depending on a plant designs specific operating margin. These involve, modest equipment replacement and little or no change to either the nuclear steam supply system {Reactor – Boiler} or turbine by limiting increase in pressure (2% to 3%) to allow sufficient mass flow margin in the high-pressure {HP} turbine. Stretch power up-rates usually involve changes to instrumentation settings but do not involve major plant modifications.

c) Extended power up-rates are greater than stretch power up-rates and EPU (Extended Power Uprate) increases the original licensed thermal power output by up to 20%. Extended power up-rates usually require significant modifications to major pieces of non-nuclear equipment such as high-pressure turbines, Feed water heaters, condensate extraction pumps, Drain pumps, Feed pumps and motors, main generators, and/or transformers.

Expected Applications for Power Up-rates:

The following information is based on the October 2008 survey of NRC licensees. Survey indicate utilities plan to submit 42 power up-rate applications in the next five years, including 21 extended power up-rates, 1 stretch power up-rates and 20 measurement uncertainty recapture up-rates. If these applications are permitted, the resulting up-rates would add another 8,683 MWt (2,894 MWe) to America’s power generating capacity.

Many Economic Returns:

There are also other benefits associated with an up-rate. Many of the existing nuclear plants have been operating for 30 years or more and require some kind of retrofits and modifications on major equipments. These and other potential plants have either completed or looking for a license renewal. Combining an up-rate with a maintenance upgrade or license extension allows some of the cost to be shared among these programs. Also utility doesn’t have to wait as long to collect the benefits of an EPU. An EPU can be brought into operation in about half the time required to license and build a new plant.

More than Replacing Components:

The success of an EPU program heavily relies on the quality of the management team, their ability to develop an effective execution plan, to schedule the work efficiently and to build valuable controls to ensure that those schedules are carried out.

It is difficult to generalize the perfect plan to complete an EPU for a given plant. Difference between previous modifications and equipment change outs to maintain plant operation all combine to make the EPU program for each nuclear plant unique.

With coal, oil and gas-fired power plants increasingly coming under criticism for damaging the environment, Nuclear energy is poised to pave the way for an important electric power generation platform for the future.

Written by Kandhan

Filed under: Business & Economy, Science & Technology, , , , , , , ,

The Concept of Green Buildings

Green Buildings are Eco Friendly Structures

When the pre historic man constructed a hut for the first time using bamboo trees and coconut leaves to protect himself from sun and rain, he was starting to exploit nature for his humble needs. Apart from killing the trees he also disturbed the natural habital of the insects and birds in those trees and interfered in the cycles of nature. That was a beginning.

Now, it is beyond imagination, how much damage has been inflicted on earth by the construction of various types of buildings using sand and water from the rivers, stones from the mountains, cement manufactured from the ingredients dug from the land. In addition, carbon emission from the buildings and manufacture of construction materials warm up the air and space.

But, after getting conscious about the environment and after feeling the environmental responsibilities, the way our people try to address this problem is wonderful. One of the intelligent initiative is the concept of “Green Buildings”.

The concept of Green Buildings envision a new approach to save water, energy and material resources in the construction and maintenance of the buildings and can reduce or eliminate the adverse impact of buildings on the environment and occupants.

 Concept of Green Buildings

A model plan of a Green Building

By preferring Green Building over a conventional building we help this planet earth and the people to retain nature to a maximum extent possible in three ways with reference to the location of the buildings.

1. Retain the external environment at the location of the building.
2. Improve internal environment for the occupants
3. Preserve the environment at places far away from the building

Green Buildings Retain the Environment at the location of the Building.

Suppose we propose a multistoried office complex to accommodate thousands of officers and staff, it requires a vast area. Therefore selection of a site for such a building complex should consider retention of local vegetation, wild life, natural water courses etc. Either a site with bio diversity should be avoided or the building should be planned to reduce site disturbance.

 Concept of Green Buildings

Concept cross section of a Green Building

Land :The landscaping and the exterior design in a green building shall be in such a way that there is more shaded area, the light trespass is eliminated and local species of plants are grown.

Water : The green building by its design and shape shall not disrupt the natural water flows, it should orient and stand just like a tree. Rain falling over the whole area of the complex shall be harvested in full either to replenish the ground water table in and around the building or to be utilized in the services of the building. The toilets shall be fitted with low flesh fixtures. The plumbing system should have separate lines for drinking and flushing. Grey water from kitchenette, bath and laundry shall be treated and reused for gardening or in cooling towers of air conditioning.

Energy: The solar energy at the top of a green building is harvested to supplement the conventional energy,. The natural light is harvested in the intermediate floors to minimize the usage of electricity. Sunlight is restricted by the high grown trees outside the lower floors of the building. High efficiency light fixtures make a pleasant lighting apart from saving the energy. High-efficiency windows and insulation in walls, ceilings, and floors are used for the benefit of better temperature control.

Green buildings improve internal environment for the occupants

Light: In a designed green building the occupants shall feel as if they are in outdoor location. The interior and exterior designs shall go hand in hand by blending the natural and artificial lighting and presenting transparent views wherever possible.

Air: In the air conditioned environment, a green building shall be specially equipped to ensure the Indoor Air Quality for a healthy atmosphere. Even the nasal feelings shall be pleasant free from the odour of paints and furnishings.

A comfortable atmosphere at work stations improve the attendance of the staff and increase the productivity.

 Concept of Green Buildings

Model elevation of another Green Building

Green buildings preserve the environment at places far away from the buildings.

We all know that a building is constructed using cement, sand, steel, stones, bricks, and a lot of finishing materials. These materials are quarried or procured from far way from the location of the buildings. Building materials are responsible for about 20 percent of the greenhouse gasses emitted by a building during its lifetime,.

Green buildings shall use the products that are non-toxic, reusable, renewable, and/or recyclable wherever possible. Locally manufactured products are prefered so that the collective material environment of the locality remains a constant and moreover the fuel for the transport of materials is saved.

As we see, our food and domestic products are tagged with green as a fashion of eco friendly practices, building materials are also going green. The futuristic green buildings are to use green materials which are in research stage now.

Green wood : A Stanford team has done a research for wood alternate. Hemp fibers and biodegradable plastic when pressed together and heated form layers and this material is as strong as wood. When buried in land fill, it degrades faster. This wood creates more raw materials when it breaks down. Microbes produce methane gas when they decompose this wood substitute and other debris thrown into landfills. Another type of bacteria absorbs this gas and turns it into plastic that can be used to create a new wooden plank. By this cycle, there is a continuous source of raw material for this wood. When this material at research comes to market, it may help to control deforestation and promote the rainfall.

Green Cement: Bruce Constantz at Calera, based in Los Gatos, has developed a green method to produce both cement and aggregate, another component of Concrete. Their method sequesters Carbon Di Oxide from power plant flues and mixes the gas with sea water to produce the mineral raw materials of concrete. For every ton of green cement Calera manufactures half a ton of fly ash from coal plants is used apart from preventing production and emission of Corbon Di Oxide.

Other Green Building materials: Renewable plant materials like bamboo (because bamboo grows quickly) and straw, lumber from forests ecology blocks, dimension stone.recycled stone, recycled metal are some of the other materials used in a Green Building.

 Concept of Green Buildings

Savings due to Green Buildings

LEED GREEN BUILDINGS RATING SYSTEM

The Buildings constructed based on the Green concepts should confirm to the prescribed standards. There should be continuous assessment and and monitoring from the planning/design stage upto the completion of construction, for declaring a building as a Green Building.

For this, LEED ( Leadership in Energy and Environmental Design ) Green Building Rating system is followed. In this system points are awarded for adopting Green concepts in various categories and the Buildings are certified Green at levels such as Silver, Gold or Platinam based on the total number of points they get in LEED Rating.

 Concept of Green Buildings

The CII-Sohrabji Godrej Green Business Centre (also known as CII or CIIGBC) earned a LEED® rating of 56 credits and became certified “LEED Platinum” in 2003;

Measurement / Audit for Green Concept in Buildings

Categories for Rating LEED points
Sustainable site 12
Water efficiency 8
Energy and atmosphere 17
Material and resources 13
Indoor Environment Quality 15
Design process and innovation 4
Employing LEED designer 1
Total points 70

Certification for Green Buildings

Level Points required
LEED Certified 26 to 32
Silver Level 33 to 38
Gold Level 40 to 52
Platinam Level 53 and above

There are only few Certified Green Buildings in India. But it is good to know that the awareness is gathering momentum and we look forward for a greener future.

Unpolluted Water,  Soil,  Mountains and thick Forests
are the Forts defending a Land

( ThiruValluvar 742)

Written by Malarthamil on the eve of observing World Environment Day on June 5

Malarthamil is a civil engineer and writer-poet inspired by Thirukkural – a classical Tamil poetry that expounds various aspects of life.

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Google Larry Page’s University of Michigan Commencement Address

It is not easy to give a commencement speech.  ie, a really useful & inspirational speech that penetrates the ears of the intelligent crowd.  But some deliver such speeches.  The above is one such commencement speech delivered to 2009 graduates, by Google co-founder Larry Page.  It has romance, compassion, perseverance, love, family, dreams, history, humor… All in all, a nice story.  Lend your ears, for a precious 15 minutes of your lives.

My father’s father worked in the Chevy plant in Flint, Michigan. He was an assembly line worker. He drove his two children here to Ann Arbor, and told them: That is where you’re going to go to college. Both his kids did graduate from Michigan. That was the American dream.

Assembly line workers, all over the world, across races, across cultures, they all want to give their kids the best educational opportunity.  They believe in themselves, they believe in their kids.  They work hard, and they have high aspirations.  They would succeed.  ie, If others in the society too have a strong conviction that ‘All men are born equal’, then the factory workers would succeed.

The optimism of youth is often underrated!

You know what it’s like to wake up in the middle of the night with a vivid dream? And you know how, if you don’t have a pencil and pad by the bed to write it down, it will be completely gone the next morning?

Well, I had one of those dreams when I was 23. When I suddenly woke up, I was thinking: what if we could download the whole web, and just keep the links and… I grabbed a pen and started writing! Sometimes it is important to wake up and stop dreaming. I spent the middle of that night scribbling out the details and convincing myself it would work. Soon after, I told my advisor, Terry Winograd, it would take a couple of weeks to download the web — he nodded knowingly, fully aware it would take much longer but wise enough to not tell me. The optimism of youth is often underrated! Amazingly, I had no thought of building a search engine. The idea wasn’t even on the radar. But, much later we happened upon a better way of ranking webpages to make a really great search engine, and Google was born. When a really great dream shows up, grab it!

We are spreading the virus with every footstep, right under beautiful kids playing everywhere.

In late March 1996, soon after I had moved to Stanford for grad school, my Dad had difficultly breathing and drove to the hospital. Two months later, he died. And that was it. I was completely devastated. Many years later, after a startup, after falling in love, and after so many of life’s adventures, I found myself thinking about my Dad. Lucy and I were far away in a steaming hot village walking through narrow streets. There were wonderful friendly people everywhere, but it was a desperately poor place — people used the bathroom inside and it flowed out into the open gutter and straight into the river. We touched a boy with a limp leg, the result of paralysis from polio. Lucy and I were in rural India — one of the few places where Polio still exists. Polio is transmitted fecal to oral, usually through filthy water. Well, my Dad had Polio. […] He would have been very upset that Polio still persists even though we have a vaccine. He would have been equally upset that back in India we had polio virus on our shoes from walking through the contaminated gutters that spread the disease. We were spreading the virus with every footstep, right under beautiful kids playing everywhere. The world is on the verge of eliminating polio, with 328 people infected so far this year. Let’s get it done soon. Perhaps one of you will do that.

-vikadakavi

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Technology: Wearable Sixth Sense by MIT lab

Sixth Sense can be available for 350$. Pattie Maes unveiled an early version of the “Sixth Sense” device at the MIT lab last month (Feb, 2009). ‘SixthSense’ is a wearable gestural interface that augments the physical world around us with digital information and lets us use natural hand gestures to interact with that information.

Pranav Mistry – a PhD student in the Fluid Interfaces Group at MIT’s Media Lab is the genius behind Sixth Sense. Pranav gave an intriguing demo of the product that shows how the device paves the way for profound interaction with our environment. Pranav holds his Masters in Design from IIT Bombay and hails from Palanpur – a small town of northern Gujarat, India. 

Posted by Sunderapandyan.

Community cheer leader, software engineer & innovator – Sunderapandyan is hard to pin down. He writes on South Asian news and issues to the world.

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