Monday, February 15, 2010

Lab Report #1

The first question is what the definition of temperature is. Temperature is a feeling of warmth or coldness of an item which can recognize by touching that item. In fact, “temperature is a measure of the average kinetic energy of the particles in a sample of matter, expressed in units of degrees on a standard scale.” Temperature units are in Fahrenheit or centigrade degrees. Since temperature is a standard measurement, the amount of particles in an object does not change the temperature range and also temperature does not depend on the size of the object. For instance, the temperature in a glass of boiling water is exactly same as the temperature of the huge tank of boiling water and it doesn’t matter that big tank carry more water molecules inside.

The particles and molecules in the objects never travel at the similar speed. Indeed there is a variety of energy in the middle of the molecules which cause the movement. Like in glass of liquid like water molecules are moving in the accidental way with different range of speed and the pace of the molecules depend on the temperature on the liquid. It means with higher temperature molecules move faster and with lower they move slower.

Temperature needs to get measure in different circumstances and there are plenty of equipments and sensors outside for measuring it. First common and practical device to measure temperature is thermometer. Thermometer work really simple and has two main elements, the temperature sensor and some numbers to converting the material change into a value.

Most frequently used temperature sensor is thermocouple. The thermocouple made from two different metals which are attached jointly at the end of one side. They touch each other and the contact point produces a small exclusive voltage as a function of temperature. This voltage is measured and read by a thermocouple thermometer. Thermocouples are accessible in diverse “metals combinations or calibrations. The four important calibrations of the thermocouples are J, K, T and E. Each calibration has a special temperature variety and environment.” Although the thermocouples are sort of temperature sensor which generally use for measurement and control they be capable to use to convert heat into electric forces. In the direction of choosing the right thermocouples for our project we need to consider different aspect of it. Since thermocouples measure in large temperature ranges and can be quite rough they are usually getting used in manufacturing. So we need to consider the temperature range, think about the chemical resistance of the thermocouple or covered material, consider abrasion and vibration resistance and at the end check our installation supplies.

One of the disadvantages of thermocouple is life time of the machine. Since in thermocouples, thermo elements are usually worked in the high temperatures the lifetime of the system will decrease. One of the electronic devices which can convert thermal energy to electrical energy is thermopile. Thermopile is a collected of thermocouples most regularly in series connection but in some special cases in parallel.

In solar radiation measurement there are different types of instruments. Such as:

Total Diffuse

Pyranometer with thermal detector- Eppley

Pyranometer with shading ring- Kipp

Total Beam or Direct

Pyranometer with PV detector- LiCor

Pyrheliometer

Bibliography
http://en.wikipedia.org
http://coolcosmos.ipac.caltech.edu
http://www.omega.com
SOS 494- Renewable Energy Class, Professor Reddy

The life-cycle cost (LCC) analysis takes into account all expenses that incur over a time span for a system. When different design scenarios are considered, this tool enables the designer to compare the net savings of different alternatives and choose the most cost-effective option. However, the simple payback analysis considers the short term return of investment for a system during the first year. Two methods i.e., manual calculation and Excel Spreadsheet, are used to determine the net savings and simple payback of a baseline system and nine other design options (glazing) and results are discussed below.
Manual Calculation:

Based on the net saving, ALT 9 (PPG - SolarBan 2000) offers the most saving over 25 years ($714,380) followed ALT 7 (Viracon -VE7-55 -Low-E Azurlite) which results in $707,770 saving. Although both designs require an initial one time investment it pays off in the long run by reducing the utility costs.

From Figure 1, it is clear that alternatives 7 and 9 offer the largest savings compared to a big others options.

Figure 1 – Net savings using manual calculation

The simple payback is the ratio of the incremental first cost over first year annual savings. Hence, it focuses on the short term returns. Figure 2 shows the simple payback results for the 9 different alternatives.

Figure 2 – Simple Payback using manual calculation

It is obvious that this method yields different results from the net saving (see Figure 1). This plot indicates the best design recommendation based on this approach is ALT 1 (Single Pane Azurlite) with a simple payback ratio of 0.8 which pays for its investment during the first year. ALT5 (Viracon -VE1-55 -Low-E Clear) comes second with a 2.9 payback value.
Excel Spreadsheet Calculation:

Figure 3: Net savings using Excel Spreadsheet

Figure 3 shows the net savings obtained from Excel Spreadsheet. As this figure indicates, the most cost-effective option over is ALT 9. This offers the largest cost saving over 25 years of service. This is inline with the conclusion from manually calculated data.

Figure 4 - Simple Payback using Excel Spreadsheet

Figure 4 shows the simple payback values calculated with the spreadsheet for nine different design alternatives. Similar to Figure 2 this graph also indicates that ALT1 offers the best return for investment during the first year.

Summary:

The simple pay back is easy to estimate and indicates the return of an investment during the first year. However, its focus is on the short term fails to capture all future costs and benefits, capital replacement, life-cycle utility costs, operations cast, maintenance costs, and the time value of money. On the other hand, net saving parameter could provide the value of an investment over a time period and the savings in the long run.

Both manual and spreadsheet methods yielded comparable results. Although there were some insignificant deviations in the results of these two methods it did not alter the final recommendation.

The Built Environment and the Ecosphere: A Global Perspective

Read the copy of chapter “The Built Environment and the Ecosphereand write about your observation:

It is a strong relationship between the growth of the urban population and development of the Countries. In the history the human population has had a rural lifestyle and the world’s population was becoming more urbanized as people move to the cities and search for urban lifestyle. By look at the chart and graphs the big jump on the population growth in the last decade sometimes between 1950 and 2010 appears. In 1950 just 25% of the world’s population used to live in cities and by the end of 2009 this number was raised to 52% and it is estimated to grow to 65% by the end of year 2030. For example, in the United States just 5% of the population lived in cities in 1850 then 70 year later in 1920 about 50% of the population lived in cities. In fact, it was a time for US to start the urbanization. This numbers grows faster than imagination which in 2009 around 85% of the US population lived in cities and suburbs. While just 100% of a population probably can be urbanized so the development of the urbanization is will finished. Historically, Urbanization has directly connected with industrialization. “When more and more inanimate sources of energy were used to enhance human productivity (industrialization), surpluses increased in both agriculture and industry.”
But what are the most important concerns related to speedy Urban Growth? The processes of the urbanization is really bigger than simple population growth, it will change the economy in the society and revolutionize the social and political arrangement of the county. Numerous environmental issues and social changes in the urban environment are the cause of urban growth and its consequence has a strong connection to global change issues. The urban growth also decreases the ability of the cities to offer well to services to residences of the city including energy, health care, transportation, physical security, trash pickup services and education. On the other hand, since administration of the city is not earning enough profit to use on the basic needs of the place, the cities will become the crowded area with severe environmental issues.

On the early 20th centuries the urbanization has a motivation for suburb people to travel to establish the developed cities. Some opportunities like new job and better life style deceived people to look for a new way of life in big cities. Simultaneously, amount of factories got opened in large cities and attract large numbers of migrants looking for employment. In addition, it was a big attraction for investment corporations from developed countries to start businesses in those cities. The major problem of the opening new factories was pollution and urban sprawl. In addition, the change in the physical surroundings and in the form and spatial society of cities is under the Urban sprawl’s responsibility.

Developed and undeveloped countries are different on the percentage of the living in cities. For instance, in some undeveloped countries like India the population of the cities is extremely high and it causes the urban sprawl. It shows that practically 60% of city residents live in the urban margin in poverty and environmental dreadful conditions. High mass arrangements are highly make pollution. Also be short of metropolitan services, including clean water, electricity, natural gas, special service for trash pickup are some problems which those poor people deal with in the daily life.

The problem in developed countries such as United State and Canada has a different shape. In those countries urban sprawl Consequences is even more. It includes the raised traffic on the center of the city as well as suburb, pollution on the water and air, damaged agricultural land and parks, large amount of cost for sewer lines and new water lines, highly cost to make more houses for more people, fire protection places, hospital and universities and finally crowded city with less space and more people on the area.

Some of the serious environmental problems which seem temporarily but would change to be permanent are atmospheric change, unsteady climate and ozone depletion. Those problems are not just affect people on the cities; they would involve people from around the world.

Another important subject related to urban growth is ecological footprint. The Ecological Footprint is the area of earth and ocean required to sustain our consumption of food, goods, services, housing, and energy and assimilate our wastes. “Our ecological footprint is expressed in "global hectares" (gha) or "global acres" (ga), which are standardized units that take into account the differences in biological productivity of various ecosystems impacted by our consumption activities. Our footprint is broken down into four consumption categories: carbon (home energy use and transportation), food, housing, and goods and services.” Our footprint is categorized into four ecosystem forms such as cropland, pastureland, forestland, and marine fisheries.

There are numerous systems to decrease our footprint in the world. By learning those systems we can be more responsible for our generation and by sharing this information with our colleges, friends and community we can make a social change to have a greener environmental in our planet. What we can do is, first use the cleaner transportation services which basically mean walk, bike, or take public transit more than before and try to avid personal car. If we have to use our car it is better to service it regularly. Instead of using airplane take bus or train if it is possible. Second, include energy-saving features to our home. For example put in compact fluorescent bulbs in our home light fixtures, check our walls and ceilings to confirm that they are insulated and if it is possible, consider double-pane windows and also choose energy efficient electrical device for the house. Third, try to track good habits for saving energy. For instance, change our thermostat to the low number in winter and same thing with air conditioning in the summer, also remember to replace dirty air conditioner filters to keep the air conditioning system operate at peak efficiency, turn off the light when we are not in the room and unplug electricity devices when is not in used.

Furthermore, there are different ways to reduce our footprint in the nature. For example buy more local, organic, in-season foods. Enjoy planting and try to plant our own herbs and vegetable. Pay attention to packaging when we shop in super market which means foods with less packaging will reduce waste on the world. Eat less meat because “globally, it has been estimated that 18% of all greenhouse gas emissions are associated with meat consumption.”

Finally what is our responsibility as a designer and how we can help as a designer or architect? The most important thing that we can do is prefer sustainable building materials, furnishings, and cleaning products. Think about using the green design features for design, same as passive solar heating, water recycling system and recycled materials. Use efficient appliances, including low flow shower heads and toilets in the building. And finally use biodegradable, non-toxic cleaning products.

In this chart shows that total surface irradiance start from 5 AM and finish at 7 PM in summer and in winter start from 7AM until 6 PM . The shape of the line illustrate that total surface irradiance in the summer time is lower and that the incidence angle on the summer is closer to the normal angle of the vertical surface.

Summer (June)

Winter (December)

Friday, February 5, 2010

The Recurring Silent Spring

Silent Spring is written by Rachel Carson and published in September 1962. The book is more about the disadvantageous effects of modern pesticides on our surroundings especially on fish and birds. It will give us some ideas about helping to start the environmental movement and green politics.

In the small city in the middle of America everything was fine and elegant and seemed to be perfect with its surrounding. Then an unexpected blight started in this beautiful area and changed everything. Chickens, Sheep, cows and other animals stared to getting sick and die. There had been several quick and unexplained deaths on the city. The farmer s talked to doctors to find the problem but this mysterious sickness made doctors confused as well as farmers. Also there was another extraordinary problem. All birds were gone and people couldn’t find the reason. Where they go and why they move. The answer to this disaster was chemical poisoning.

The industry started to grow after World War II and using the chemical suddenly rise. For example The DDT in environment can cause thinner on egg shells and make a reproductive problems and death. Also the chemical industry of spreading disinformation and public officials of accepting industry claims uncritically.

Almost three decade later the Environmental Protection Agency (EPA) find a solution to unsolved problems of sickness and death of wildlife, flowers, vegetable, animals, children and adults . EPA evaluates harmful waste sites by the same standard which Silent Spring book was used to present “fable for tomorrow “. Hazardous ranking system was a methodology to identifying the most dangerous hazardous waste sites. It included the category and amount of the hazardous of the chemical which is used on the site, drinking water wells or supplies, verification of the stressed vegetation and ground water, surface water and air. EPA got $1.6 billion fund from congress to rank, investigate and clean up some super dangerous waste sites in the United State on five years.

The super fund program worked very well and got more funds with more number of serious hazardous waste sites to clean up. But one of the criticisms is “so much toxic waste buried, so few sites cleaned up”.

During the time that EPA was focused on its project - hazardous waste program - environment movement was dealing with different problems. There are two main concern (one urban and one rural) on chemical usages in environment. First problem is agricultural pollution. For example farmers pollute their own wells and local water supplies with agricultural chemicals. Unfortunately there are not enough budgets to replace or restore the groundwater or clean up the surface water. The public agency answer to this problem is “do nothing philosophy” and ignore the fact. Second problem is, employing the high level of lead in urban earth in different areas. Scientists on Boston City Hospital on their studies found high level - as high as 1-of lead poisoning on children’s blood. The fact is rate of the blood lead poisoning was different in each neighborhood. Some children which live in the poor region have more exposed to lead from gasoline, leaded paint from housing and the dirt which they use to play with. EPA started a project to remove lead contaminated soil in those properties. They called it Emergency Lead Poisoning Area because of the high amount of lead-poisoned kids.

Two large factions of chemicals are making the majority of pesticides. The chlorinated hydrocarbons (including: DDT, chlordane, heptachlor, dieldrin, aldrin, and endrin) and phosphorus insecticides which are directly linked to the poisonous nerve gases used in World War II. They affect the nervous system of their subject such as insect, birds, animals and humans.

One of the important subject that Carson is concern about is the risk of the pesticides water especially ground water. In fact, ground water can count as an underground sea which is getting recharged by rain and snow. Rain will pass the poisoned soil to get underground and take the poison to the water.

The Nature of Exponential Growth

In our decade five main elements such as population, food manufactured industrialization, pollution- especially green house gases- and consumption of non renewable natural resources are increasing annually. Exponential growth is the name of the pattern which shows the amount of increasing every year. In general, there are two different types of graph to show the increasing, linear and exponential. When graphs show the rate (positive or negative) base on the fixed rate we name it linear graph and when the elements which are involved on the graph doesn’t move with fixed speed we name it exponential. For instance the process of the birth is exponential. Each cell divide to two cells and these two cells again divide to another two cells and finally after the specified period of time amount get doubled or tripled. From two to four, four to sixteen, sixteen to thirty two and… In exponential increasing the object rise much faster than linear. Indeed, exponential growth is an ordinary progression in nature and many other systems in the planet.

In the exponential growth when one option gets changed over time like financial matters the result would be predictable and easy to understand. But in complicated cases like nature topics with diverse alternatives analyses the outcome of the growth and predict the future behavior would be really hard. Some serious questions get involved with the complicated cases. For example, population causes the pollution or manufacturing? Is either one individually in charge for population or both? Is population affects more food production or lack of non renewable energy is involved with the issue? How much location and social behavior can change the result on the long term? For finding the answers to all questions above it is better to understand and analyses the whole complex system. System Dynamic is a straightforward method to understanding the dynamic behavior of complicated systems. Firs t of all we need to recognize the basic structure of the system that we are working on. Then get familiar with positive feedback loop or “vicious circle”. Feedback loop is a series of cause and effects that all exponential growing quantity is involved with. It means when any elements in the loop get changed by any other relative purposes (toward positive) feedback loop will start a chain of increasing changes and final result even increased more like exponential and when any elements goes in the direction of the negative feedback loop the result will decrease.

In general positive feedback loop is a good option when we want to begin our dynamic analyses of the long -term world condition. In the dynamic behavior of population growth, positive feedback loop that accounts for the observed exponential growth. In larger population -with steady standard fertility- because more people are involved, more babies will be born annually and more babies will show more population on each year graph. After some times to allow those babies to become adult and have their babies as a result more babies will born again and population will grow more and more. Steady growth will keep going as long as standard fertility stays stable with same condition. But some alternative like location, diet habits, and exercises can change the result.

In different areas, average genders of the babies are dissimilar. For example, if each woman has two or more female children in their households and each of them become adult and have more than two female children in the period of time the population will be double or more in the following generation. On the other hand the negative feedback loop is controlling the population. Negative feedback loop is based on the number of death each year and the mortality in each year depends on the several alternatives such as health of the community, natural disaster like earthquake, tornado, flood and war between countries.

There is an unbreakable chain between the positive and negative feedback loop. More birth in the community results rising the average population and because of more people in the world we have more death on the community. Also, more death leaves fewer people and less birth for the next generation. If there is no death which is impossible cause positive feedback loop of birth rise exponentially. If this case is an impossible case so what is the reason that the world population grows exponential? Is it because of the industrial revolution that changed the balance of the birth and death?

Three decade ago the life time average was just 30 years old. 30% of the children under five couldn’t survive from the child diseases. 40% of pregnant women delivered a death baby or they were died in the process of delivery. But now because of the modern medicine, public health methods and cleaner water and distribute food death rates especially in modern countries decreasing around the world.

Although the food, resources, clean water and healthy neighboring are the big factor for growth the social problems, culture in different areas and location play a big role in controlling the birth and death. For instance, in some countries like India, Zambia, Pakistan and Colombia the death of the small children is still on the board. Clean water and natural food is a problem that they are dealing week every day.

Another problem is faster than human population world economic is growing exponential. The regular growth range was 7 percent around forty years ago and the reason is the increasing amount of industrial capital including factories, trucks, machines and different tools. By calculation and consider that 7 percent economic is growing and 2 percent population growing that main positive feedback loop are increasing terrifying.

The big question is what we need to sustain world economic rate and population growth. We can list our answer into two categories. First, the physical requirements that maintains all physiological and manufacturing activities like, water, food, fossil fuel, unprocessed material, nuclear fuel and ecological system which absorb waste and recycle materials. The second category is social requirements. Social requirements factor includes education, social life, employment and technological process.

Temperature, Radiation Measurement Devices & Methods

The first question is what the definition of temperature is. Temperature is a feeling of warmth or coldness of an item which can recognize by touching that item. In fact, “temperature is a measure of the average kinetic energy of the particles in a sample of matter, expressed in units of degrees on a standard scale.” Temperature units are in Fahrenheit or centigrade degrees. Since temperature is a standard measurement, the amount of particles in an object does not change the temperature range and also temperature does not depend on the size of the object. For instance, the temperature in a glass of boiling water is exactly same as the temperature of the huge tank of boiling water and it doesn’t matter that big tank carry more water molecules inside.

The particles and molecules in the objects never travel at the similar speed. Indeed there is a variety of energy in the middle of the molecules which cause the movement. Like in glass of liquid like water molecules are moving in the accidental way with different range of speed and the pace of the molecules depend on the temperature on the liquid. It means with higher temperature molecules move faster and with lower they move slower.

Temperature needs to get measure in different circumstances and
there are plenty of equipments and sensors outside for measuring it. First common and practical device to measure temperature is thermometer. Thermometer work really simple and has two main elements, the temperature sensor and some numbers to converting the material change into a value.

Most frequently used temperature sensor is thermocouple. The thermocouple made from two different metals which are attached jointly at the end of one side. They touch each other and the contact point produces a small exclusive voltage as a function of temperature. This voltage is measured and read by a thermocouple thermometer. Thermocouples are accessible in diverse “metals combinations or calibrations. The four important calibrations of the thermocouples are J, K, T and E. Each calibration has a special temperature variety and environment.” Although the thermocouples are sort of
temperature sensor which generally use for measurement and control they be capable to use to convert heat into electric forces. In the direction of choosing the right thermocouples for our project we need to consider different aspect of it. Since thermocouples measure in large temperature ranges and can be quite rough they are usually getting used in manufacturing. So we need to consider the temperature range, think about the chemical resistance of the thermocouple or covered material, consider abrasion and vibration resistance and at the end check our installation supplies.

One of the disadvantages of thermocouple is life time of the machine. Since in thermocouples, thermo elements are usually worked in the high temperatures the lifetime of the system will decrease. One of the electronic devices which can convert thermal energy to electrical energy is thermopile. Thermopile is a collected of thermocouples most regularly in series connection but in some special cases in parallel.