Clean Technology:
A greener aspect to development

Institute of Business Administration University of Dhaka

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Economics of Geography and Environment (G101)

Clean Technology: a greener aspect to development

Clean Technology: A greener aspect to development

Prepared for: Dr. A. M. M. Amanat Ullah Khan Professor, Department of Geography and Environment University of Dhaka
Prepared by: Ahamed Najeeb Rahman ZR-74 Tasnia Azim Choudhury RH-76 M. Samiul Haque ZR-84 Jidny Rubaiyat Shoummo ZR-85 Zahin Azad Moslem ZR-121

BBA 20th Date of Submission: June 15, 2012

Institute of Business Administration University of Dhaka

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LETTER OF TRANSMITTAL
15 June, 2012. Dr. A. M. M. Amanat Ullah Khan Course Instructor Economics of Geography and Environment University of Dhaka Subject: Letter of transmittal for Economics of Geography and Environment course termpaper. Dear Sir, Here is the report which you asked us to submit for the requirement of our undergraduate course- Economics of Geography and Environment (G101). The title of the report is “Clean technology: a greener aspect to development”, which is a descriptive analysis of how Green Technology works and can help the environment. This report has been prepared under your authorization. Without your permission, no part of this report can or will be revealed. This report never has been, and never will be, reproduced for any other IBA course. We sincerely hope that you we were able to fulfil the course requirement successfully through the submission of this report. We have put in our best efforts to contribute towards the successful completion of this report. We hope that you will accept our report and that it will reach your level of expectations. We have tried to make the report as comprehensive as we possibly could but we would appreciate you contacting on us if you find any imprecision. Sincerely, Ahamed Najeeb Rahman ZR-74 Tasnia Azim Choudhury RH-76 M. Samiul Haque ZR-84 Jidny Rubaiyat Shoummo ZR-85 Zahin Azad Moslem ZR-121

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TABLE OF CONTENTS
Summary iii

1.0 Introduction 1.1 Origin of the report 1.2 Objectives 1.3 Scope 1.4 Methodology 1.5 Limitations

1 1 1 1 2 2

2.0 What is Green Technology

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3.0 Prominent Examples of green Technology 3.1 Solar Energy 3.2 Biofuels 3.3 Green Building

7 7 15 21

4.0 Conclusion

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Clean Technology: a greener aspect to development

SUMMARY
In a world of rapid growth, both in terms of economy and population, human beings have sought to influence the environment around them for a better, more efficient and easier life. The resources that we have used up from the environment have often been nonrenewable and in our heedless march to glorious comfort, we have ignored the consequences of the effect that we are having on the world we live in. With the results of our negative impact on nature coming around to haunt us, there have been a rising global awareness and movement to better ourselves. Green technology is a major part of it.

Green technology is the application of the environmental science to conserve the natural environment and resources, and to curb the negative impacts of human involvement. The main idea behind green technology is to provide sustainable growth. That is, using resources from the Earth in a renewable fashion.

The following report outlines some aspects of green technology and discusses three main ideas: Solar energy, Green Buildings, Biofuels.

In the report, it has been discussed how each of these technologies are environmentfriendly, how they are being used globally and what the advantages of use are. Each of these technologies can be used in the everyday life of an individual as a source of energy, as a mode of living and as an alternative source of fuel, which collectively can improve the ecology and the habitat throughout Earth and check the currently deteriorating conditions of the environment.

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Economics of Geography and Environment (G101)

Clean Technology: a greener aspect to development

1.0 INTRODUCTION
This report provides information on green technology otherwise known as environmental technology. The goals of this report along with the means of acquiring information, its span and shortcomings are discussed in this section.

1.1 Origin of the Report
As part of the course requirement of the Economic Geography & Environment (G101) course, each group of students is required to prepare a report on any topic related to the course. Our group has decided, with the approval of the course instructor, to prepare the report on Green Technology.

1.2 Objectives
Our goals are to:  Introduce the concept of Green Technology; highlight its purpose and its growing significance in the context of the modern global environment.

 Describe sustainable energy generation technologies, possible solutions such as electronic devices to monitor, model and conserve the natural environment and resources, and to curb the negative impacts of human involvement.

1.3 Scope
 The report is based on secondary data available on the World Wide Web regarding green technology.  3 particular types of technology; namely Solar Energy, Green Building and Biogas.

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Clean Technology: a greener aspect to development

1.4 Methodology
The report is based on secondary data. Green Technology was first searched for on the internet. Then the report was compiled using information available on various websites regarding green technology. As for the 3 technologies chosen, the three most popular green technologies were chosen. This was done by taking a holistic approach and taking the technologies which are supposed to have the biggest impacts in the near future.

1.5 Limitations
The main problem we faced when preparing the report:  No way to verify the authenticity of the data used to compile the report.

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2.0 Green Technology
The term "technology" refers to the application of knowledge for practical purposes.

The field of "green technology" encompasses a continuously evolving group of methods and materials, from techniques for generating energy to non-toxic cleaning products.

The present expectation is that this field will bring innovation and changes in daily life of similar magnitude to the "information technology" explosion over the last two decades. In these early stages, it is impossible to predict what "green technology" may eventually encompass.

The goals that inform developments in this rapidly growing field include:

Sustainability - meeting the needs of society in ways that can continue indefinitely into the future without damaging or depleting natural resources. In short, meeting present needs without compromising the ability of future generations to meet their own needs.

"Cradle to cradle" design - ending the "cradle to grave" cycle of manufactured products, by creating products that can be fully reclaimed or re-used.

Source reduction - reducing waste and pollution by changing patterns of production and consumption.

Innovation - developing alternatives to technologies - whether fossil fuel or chemical intensive agriculture - that have been demonstrated to damage health and the environment.

Viability - creating a center of economic activity around technologies and products that benefit the environment, speeding their implementation and creating new careers that truly protect the planet.

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Clean Technology: a greener aspect to development

Green technology is a part of the modern environmental movement which can be traced to attempts in nineteenth-century Europe and North America to expose the costs of environmental negligence, notably disease, as well as widespread air and water pollution, but only after the Second World War did a wider awareness begin to emerge. Environmental awareness as we know it started in the late 1960s and early 1970s, though the full glaring threat due to human exploitation of the environment was not realized until the last couple of decades.

With effects such as global warming, extinction of animal species thanks to loss of habitation, predictions of abnormal sea level rises leading to great variations in weather patterns resulting in powerful hurricanes and flooding, protecting the environment and if not reversing, at least reducing our heavy-handed dealings with nature has become one of the foremost global issues. And one of the main problems is the carbon emissions of the human population. One aspect of Green Technology is to reduce the carbon footprint of every human, i.e. the amount of carbon emitted by a person due to his daily activities. This involves everything from going to work to using the computer.

Green technologies include, but are not limited to, the following areas:

Environmentally preferred purchasing
This government innovation involves the search for products whose contents and methods of production have the smallest possible impact on the environment, and mandates that these be the preferred products for government purchasing.

Green nanotechnology
Nanotechnology involves the manipulation of materials at the scale of the nanometer, one billionth of a meter. Some scientists believe that mastery of this subject is forthcoming that will transform the way that everything in the world is manufactured. "Green nanotechnology" is the application of green chemistry and green engineering principles to this field.

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Clean Technology: a greener aspect to development

Recycling
It is a worldwide phenomenon, which is a basic application towards the concept of Green Technology. It shows and encourages people to reuse items that can be reusable. Items like saving cans of food or drinks, paper etc. have been encouraged by the governing bodies around the world, to be recycled so that it can be used in the future for several other purposes. It can thus help protect the environment and cause less waste/pollution.

Green chemistry
The invention, design and application of chemical products and processes to reduce or to eliminate the use and generation of hazardous substances

Water Purification
It is the whole idea of having dirt/germ/pollution free water flowing throughout the environment. Many other phenomena lead from this concept of Purification of water. Water Pollution is the main enemy of this concept, and various campaigns and activists have been organized around the world to help purify Water. Considering the amount of water usage that is under current consumptions, this concept is of utter importance.

Sewage Treatment
Sewage Treatment is a concept that is really close to Water Purification. Sewage Treatment is the process of cleaning sewage water and making it reusable; a sort of water recycling.

Green building Green building encompasses everything from the choice of building materials to where a building is located.

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Renewable Energy
Energy that can be replenished easily is the easiest way to explain renewable energy. For years we have been using sources like wood, sun, water etc. for means for producing energy. Energy that can be produced by natural objects like wood, sun, wind etc. is considered to be renewable. Fossil fuels are considered non-renewable as they take a very long time to form.

In this report, the green technologies discussed can have a direct effect on an individual helping to better the environment by:   

using clean fuel using renewable energy living in an environment friendly home

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3.0 Prominent Examples of Green Technology
There are three important types of Green Technology.

3.1 Solar Energy
The heat and light energy radiated by the sun is collectively known as solar energy. Although solar energy has been harnessed by humans since ancient times, the need for harnessing solar energy has never been greater than it is at this point of time when the threat posed by global warming is rising at an ever increasing rate. One of the most widely used sources of energy, fossil fuels, contributes generously to global warming. Moreover, fossil fuels which provide almost 80%85% of the worldwide energy are scarce and distributed unevenly under beneath earth’s surface. If solar energy is used as an alternate source of energy to fossil fuel further global warming could be reduced to a great extent. On top of that sunlight is the most abundant and a never ending source of energy.

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The Earth receives 174 petawatts (PW; 1PW=1015 W) of incoming solar radiation at the upper atmosphere. Approximately 30% is reflected back to space. Earth's land surface and water bodies absorb almost 51% of the solar radiation. 19% energy is absorbed by the atmosphere and cloud. Water from the different water bodies around the globe absorb energy thus, evaporating and rises causing atmospheric circulation or convection which returns almost 7% of the energy absorbed by the land and oceans to space. The latent heat in water vapor carries back 23% of the energy, absorbed by the land and water bodies, to the clouds and atmosphere. Sunlight absorbed by the oceans and land masses keeps the surface at an average temperature of 14 °C. By photosynthesis green plants convert solar energy into chemical energy, which produces food, wood and the biomass from which fossil fuels are derived. The total solar energy absorbed by Earth's atmosphere, oceans and land masses is approximately 3,850,000 exajoules (EJ; 1EJ=1018 J) per year. Photosynthesis captures approximately 3,000 EJ per year in biomass. The amount of solar energy reaching the surface of the planet is so vast that in one year it is about twice as much as will ever be obtained from all of the Earth's non-renewable resources of coal, oil, natural gas, and mined uranium combined. Solar energy can be harnessed in different levels around the world. Depending on a geographical location the closer to the equator the more "potential" solar energy is available.

Applications of solar energy
Solar energy can be applied in various ways. Starting from generating electricity to air-conditioning a house to cooking, solar energy can be used in a number of day to day life activities. A few of them are listed below.

a) Designing and Urban Planning Solar architecture involves positioning buildings so as to reduce extreme exposure to the sun and using materials with lower heat capacities in the

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Clean Technology: a greener aspect to development

buildings. It also includes painting buildings with light colors so as to reflect sunlight and designing houses with a large number of windows. The advantages from adopting such procedures are that the buildings get less heated which reduces the need for using air-conditioners which in turn saves a lot of energy. More windows also helps in the same way because they allow better ventilation and they also allow more day-light to enter the buildings thus, reducing the need for using lights during the day time. b) In cultivating Agriculture seeks to harness solar energy in order to optimize the productivity of plants. Techniques such as timed planting cycles, tailored row orientation, staggered heights between rows and the mixing of plant varieties can improve crop yields. Applications of solar energy in agriculture aside from growing crops include pumping water, drying crops, brooding chicks and drying chicken manure. Greenhouses convert solar light to heat, enabling year-round production and the growth (in enclosed environments) of specialty crops and other plants not naturally suited to the local climate. c) Solar Lighting As mentioned above using daylight in order to illuminate interiors is one way to save a lot of energy. Day lighting design implies careful selection of window types, sizes and orientation. When day lighting features are properly implemented they can reduce lighting-related energy requirements by 25%. Hybrid solar lighting is an active solar method of providing interior illumination. HSL systems collect sunlight using focusing mirrors that track the Sun and use optical fibers to transmit it inside the building to supplement conventional lighting. In single-story applications these systems are able to transmit 50% of the direct sunlight received.

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d) Water Heating Solar hot water systems use sunlight to heat water. In low geographical latitudes (below 40 degrees) from 60 to 70% of the domestic hot water use with temperatures up to 60 °C can be provided by solar heating systems. The most common types of solar water heaters are evacuated tube collectors (44%) and glazed flat plate collectors (34%) generally used for domestic hot water; and unglazed plastic collectors (21%) used mainly to heat swimming pools. e) Heating, cooling and ventilation Solar heating, cooling and ventilation technologies can be used to save a large amount of energy. Thermal mass is any material that can be used to store heat—heat from the Sun in the case of solar energy. Common thermal mass materials include stone, cement and water. Historically they have been used in arid climates or warm temperate regions to keep buildings cool by absorbing solar energy during the day and radiating stored heat to the cooler atmosphere at night. However they can be used in cold temperate areas to maintain warmth as well. The size and placement of thermal mass depend on several factors such as climate, day lighting and shading conditions. When properly incorporated, thermal mass maintains space temperatures in a comfortable range and reduces the need for auxiliary heating and cooling equipment. A solar chimney (or thermal chimney, in this context) is a passive solar ventilation system composed of a vertical shaft connecting the interior and exterior of a building. As the chimney warms, the air inside is heated causing an updraft that pulls air through the building. Performance can be improved by using glazing and thermal mass materials in a way that mimics greenhouses.

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f) Cooking Solar cookers use sunlight for cooking, drying and pasteurization. They can be grouped into three broad categories: box cookers, panel cookers and reflector cookers. A basic box cooker consists of an insulated container with a transparent lid. Panel cookers use a reflective panel to direct sunlight onto an insulated container. Reflector cookers use various concentrating geometries (dish, trough, Fresnel mirrors) to focus light on a cooking container. There are also technologies such as the solar bowl and Scheffler reflectors when installed use solar energy for cooking.

g) Electricity generation

Sunlight can be converted into electricity by using solar panels, which are large flat panels made up of many individual solar cells, photovoltaics (PV), concentrating solar power (CSP), and various experimental technologies. PV has mainly been used to power small and medium-sized applications, from the calculator powered by a single solar cell to off-grid homes powered by a photovoltaic array. For large-scale generation, CSP plants like SEGS have been the norm but recently multi-megawatt PV plants are becoming common.
h) Solar Vehicles

Vehicles running on petrol and gas contribute considerably to air pollution. Scientists have been working on developing environmentally friendly cars which will run on solar power. Some vehicles use solar panels for auxiliary power, such as for air conditioning, to keep the interior cool, thus reducing fuel consumption.

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Clean Technology: a greener aspect to development

Methods of storing solar energy
There are several ways of storing solar energy. Some of them are listed below:-

a) Batteries for storage Batteries are the most common methods for storage of solar energy. There are 2 types of batteries available. They are nickel cadmium and lead acid. The lead acid batteries are cheap and preferred for solar energy storage. They are similar to your car battery. The nickel cadmium battery also functions in the same manner but are expensive. However the nickel cadmium batteries discharge more electricity and also last longer. Due to the mechanism fitted in the solar panels the battery gets charged even when there is not enough sunlight concentration on the panels. Thus it is possible to run all your electrical appliances in all circumstances where the light that hits the solar panels may differ in amounts.

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b) Natural zeolites for solar energy storage Zeolite is a mineral made of alkali or alkaline earth metal with crystal water. Experiments conducted using the 13X synthetic zeolites have shown positive results for solar energy storage. Further studies showed that natural zeolites could be used as replacements for the synthetic zeolites for solar energy storage. The amount of radiation that the solar energy emits differs with the weather changes, the season and day and night conditions in the same place.

c) Sensible heat storage For the solar energy units that have middle and low temperatures the cheapest way of storing energy is to use water and stones. The energy that is collected by the collectors increase the temperatures of the storing mediums to allow storage of the energy in these mediums and when required the heat is used. In this method of solar energy storage the concentration level is low and the duration is also short.

d) Latent heat storage In this type of solar energy storage the medium for storing the energy has features like absorption of big energy, less volume and corrosion and greater repeating capabilities. At present the most effective mediums for this type of solar energy storage are hydrate carbonates, nitrates and sulphates. In latent heat storage method the energy storing density is high with longer periods of storage. The medium can be cooled easily also which makes it difficult for the medium to crystallize.

e) Chemical reaction energy storage Here, the endothermic reaction of the chemicals is used for storing the solar energy. When the process is inversed the heat is released. Here some inorganic oxides are also used as the medium. By using this method you benefit by storing heat in larger quantities and for longer periods of time. For the generation of high

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Clean Technology: a greener aspect to development

temperature by the endothermic reactions the equipment that is needed is very costly. Zeolites have the unique characteristics to absorb and deabsorb water which makes it the preferred material for solar energy storage. When the zeolites are heated the water molecules escape and the heat energy is stored. When the process of reabsorbing the water molecules starts the heat energy is released.

Advantages of solar power and solar power applications
a) It is Easy to install and easy to access which means solar power can be used almost anywhere. Starting from houses, offices, factories, malls, crowded areas to sparsely populated areas solar power is accessible everywhere.

b) Solar power and energy creates something like 5 times as many jobs as the equivalent conventional energy systems per unit of energy generated.

c) The price or running cost is virtually constant with the cost being for a capital installation. This is unlike conventional oil, coal or gas energy which will inevitably rise as these natural resources get consumed and become scarce.

d) There is no greenhouse gas effect or air pollution created by solar powered installations. In these days of confirmed climate change this is critical. It has been estimated that a single solar powered home heating system saves the polluting equivalent of driving a car for about 4,000 miles.

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e) In addition to saving the atmosphere from polluting gases solar powered applications have the effect of reducing by as much as 98% the water required (and blown away as steam) of a conventionally generated MW of electricity.

3.2Biofuels
The term biofuels indicates primarily liquid fuels derived from plant materials. Biogas also falls under biofuels. Biofuels burn cleanly and thus minimize air pollution. They are also easy to handle like other gaseous and liquid fuels. As such, biofuels are considered a green alternative and in recent years, the use of biofuels has increased. Biofuels provided 1.8% of the world’s transport fuel in 2008. Investment into biofuels production capacity exceeded $4 billion worldwide in 2007 and is growing.

Here is an overview of a few common biofuel productions and usage.

First generation biofuels
'First-generation biofuels' are biofuels made from sugar, starch, vegetable oil, or animal fats using conventional technology. The basic feedstock for the production of first generation biofuels are often seeds or grains such as wheat, which yields starch that is fermented into bioethanol, or sunflower seeds, which are pressed to yield vegetable oil that can be used in biodiesel. These feedstocks could instead enter the animal or human food chain, and as the global population has raised their use in producing biofuels has been criticised for diverting food away from the human food chain, leading to food shortages and price rises.

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Bioalcohols

Biologically produced alcohols, most commonly ethanol, and less commonly propanol and butanol, are produced by the action of microorganisms and enzymes through the fermentation of sugars or starches (easiest), or cellulose (which is more difficult). Biobutanol (also called biogasoline) is often claimed to provide a direct replacement for gasoline, because it can be used directly in a gasoline engine.

Ethanol fuel is the most common biofuel worldwide, particularly in Brazil. Alcohol fuels are produced by fermentation of sugars derived from wheat, corn, sugar beets, sugar cane, molasses and any sugar or starch that alcoholic beverages can be made from (like potato and fruit waste, etc.). The ethanol production methods used are enzyme digestion (to release sugars from stored starches), fermentation of the sugars, distillation and drying. The distillation process requires significant energy input for heat (often unsustainable natural gas fossil fuel, but cellulosic biomass, the waste left after sugar cane is pressed to extract its juice, can also be used more sustainably).

Ethanol can be used in petrol engines as a replacement for gasoline; it can be mixed with gasoline to any percentage.

Many car manufacturers are now producing flexible-fuel vehicles (FFV's), which can safely run on any combination of bioethanol and petrol, up to 100% bioethanol. They dynamically sense exhaust oxygen content, and adjust the engine's computer systems, spark, and fuel injection accordingly. This adds initial cost and ongoing increased vehicle maintenance. FFV internal combustion engines are becoming increasingly complex, as are multiple-propulsion-system FFV hybrid vehicles, which impacts cost, maintenance, reliability, and useful lifetime longevity.

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Even dry ethanol has roughly one-third lower energy content per unit of volume compared to gasoline, so larger / heavier fuel tanks are required to travel the same distance, or more fuel stops are required. With large current un-sustainable, nonscalable subsidies, ethanol fuel still costs much more per distance traveled than current high gasoline prices in the United States.

Methanol is currently produced from natural gas, a non-renewable fossil fuel. It can also be produced from biomass as biomethanol. The methanol economy is an interesting alternative to the hydrogen economy, compared to today's hydrogen produced from natural gas, but not hydrogen production directly from water and state-of-the-art clean solar thermal energy processes.

Butanol is formed by ABE fermentation (acetone, butanol, ethanol) and experimental modifications of the process show potentially high net energy gains with butanol as the only liquid product. Butanol will produce more energy and allegedly can be burned "straight" in existing gasoline engines (without modification to the engine or car), and is less corrosive and less water soluble than ethanol, and could be distributed via existing infrastructures.

Biodiesel

In some countries biodiesel is less expensive than conventional diesel. Biodiesel is the most common biofuel in Europe. It is produced from oils or fats using transesterification and is a liquid similar in composition to fossil/mineral diesel. Its chemical name is fatty acid methyl (or ethyl) ester (FAME). Oils are mixed with sodium hydroxide and methanol (or ethanol) and the chemical reaction produces biodiesel (FAME) and glycerol. One part glycerol is produced for every 10 parts biodiesel. Feedstocks for biodiesel include animal fats, vegetable oils, soy, rapeseed, jatropha, mahua, mustard, flax, sunflower, palm oil, hemp, field pennycress, pongamia pinnata and algae. Pure biodiesel (B100) is by far the lowest emission diesel fuel. Although liquefied petroleum gas and hydrogen have

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cleaner combustion, they are used to fuel much less efficient petrol engines and are not as widely available.

Biodiesel can be used in any diesel engine when mixed with mineral diesel. The majority of vehicle manufacturers limit their recommendations to 15% biodiesel blended with mineral diesel. In some countries manufacturers cover their diesel engines under warranty for B100 use, although Volkswagen of Germany, for example, asks drivers to check by telephone with the VW environmental services department before switching to B100. Many current generation diesel engines are made so that they can run on B100 without altering the engine itself.

Since biodiesel is an effective solvent and cleans residues deposited by mineral diesel, engine filters may need to be replaced more often, as the biofuel dissolves old deposits in the fuel tank and pipes. It also effectively cleans the engine combustion chamber of carbon deposits, helping to maintain efficiency. Biodiesel is also an oxygenated fuel, meaning that it contains a reduced amount of carbon and higher hydrogen and oxygen content than fossil diesel. This improves the combustion of fossil diesel and reduces the particulate emissions from un-burnt carbon.

Biodiesel is safe to handle and transport because it is as biodegradable as sugar, 10 times less toxic than table salt, and has a high flashpoint of about 148C compared to petroleum diesel fuel, which has a flash point of 52C.

Bioethers

Bio ethers (also referred to as fuel ethers or fuel oxygenates) are cost-effective compounds that act as octane rating enhancers. They also enhance engine performance, whilst significantly reducing engine wear and toxic exhaust emissions. Greatly reducing the amount of ground-level ozone, they contribute to the quality of the air we breathe.

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Biogas

Biogas is produced by the process of anaerobic digestion of organic material by anaerobes. It can be produced either from biodegradable waste materials or by the use of energy crops fed into anaerobic digesters to supplement gas yields. The solid byproduct, digestate, can be used as a biofuel or a fertilizer. Biogas contains methane and can be recovered from industrial anaerobic digesters and mechanical biological treatment systems. Landfill gas is a less clean form of biogas which is produced in landfills through naturally occurring anaerobic digestion. If it escapes into the atmosphere it is a potent greenhouse gas.

Oils and gases can be produced from various biological wastes:  

Thermal depolymerization of waste can extract methane and other oils similar to petroleum. GreenFuel Technologies Corporation developed a patented bioreactor system that uses nontoxic photosynthetic algae to take in smokestacks flue gases and produce biofuels such as biodiesel, biogas and a dry fuel comparable to coal.



Farmer can produce biogas from manure from their cows by getting a anaerobic digester (AD).

Second generation biofuels
Second-generation biofuel production processes can use a variety of non-food crops. These include waste biomass, the stalks of wheat, corn, wood, and special-energy-orbiomass crops (e.g. Miscanthus). Second generation (2G) biofuels use biomass to liquid technology, including cellulosic biofuels from non-food crops. Many second generation

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biofuels are under development such as biohydrogen, biomethanol, DMF, Bio-DME, Fischer-Tropsch diesel, biohydrogen diesel, mixed alcohols and wood diesel.

Cellulosic ethanol production uses non-food crops or inedible waste products and does not divert food away from the animal or human food chain. Lignocellulose is the "woody" structural material of plants. This feedstock is abundant and diverse, and in some cases (like citrus peels or sawdust) it is in itself a significant disposal problem.

Third generation bio-fuels
Algae fuel, also called oilgae or third generation biofuel, is a biofuel from algae. Algae are low-input, high-yield feedstocks to produce biofuels. Based on laboratory experiments, it claimed that Algae can produces up to 30 times more energy per acre than land crops such as soybeans, but these yields have yet to be produced commercially. With the higher prices of fossil fuels (petroleum), there is much interest in algaculture (farming algae). Algae fuel still has its difficulties though, for instance to produce algae fuels it must be mixed uniformly, which, if done by agitation, could affect biomass growth. Most biofuel production comes from harvesting organic matter and then converting it to fuel but an alternative approach relies on the fact that some algae naturally produce ethanol and this can be collected without killing the algae. The ethanol evaporates and then can be condensed and collected. The company Algenol is trying to commercialize this process.

Advantages of using Biofuels
There are several advantages, both environmental and economic, of using biofuels. Those are discussed below.

Advantages  Using biofuels can reduce the amount of greenhouse gases emitted. They are a much cleaner source of energy than conventional sources.

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

As more and more biofuel is created there will be increased energy security for the country producing it, as they will not have to rely on imports or foreign volatile markets.

       

First generation biofuels can save up to 60% carbon emissions and secondgeneration biofuels can save up to 80%. Biofuels will create a brand new job infrastructure and will help support local economies. This is especially true in third world countries. There can be a reduction in fossil fuel use. Biodiesel can be used in any diesel vehicle and it reduces the number of vibrations, smoke and noise produced. Biodiesel is biodegradable. They are non-toxic. They are renewable. Biodiesel has a high flash point, making it safer and less likely to burn after an accident.

3.3 Green Building
Green Building is also known as sustainable building. It is the practice of creating structures and using processes that are environmentally responsible and resource-efficient throughout a building's life-cycle from sitting to design, construction, operation, maintenance, renovation, and deconstruction. This practice expands and complements the classical building design concerns of economy, utility, durability, and comfort. Although new technologies are continually being developed to complement current practices in creating environment friendly structures, the common objective is that green buildings are designed to reduce the overall impact of the built environment on human health and the natural environment by:

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  

Powerfully using energy, water, and other resources Protecting inhabitant health and improving employee output Reducing waste, contamination and environmental ruin

A similar concept is natural building, which is usually on a smaller scale and tends to focus on the use of natural materials that are available locally. Other related topics include sustainable design, green architecture, and energy efficient buildings.

Building and the environment
Green building practices aim to diminish the environmental impact of buildings. Buildings account for a large amount of land use, energy and water consumption, and air and atmosphere alteration. In the United States, more than 2,000,000 acres (8,100 km) of open space, wildlife SUPS habitat, and wetlands are developed each year. As of 2006, buildings used 40 percent of the total energy consumed in both the US and European Union. In the US, 54 percent of that percentage was consumed by residential buildings and 46 percent by commercial buildings. In 2002, buildings used approximately

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Economics of Geography and Environment (G101)

Clean Technology: a greener aspect to development

68 percent of the total electricity consumed in the United States with 51 percent for residential use and 49 percent for commercial use. 38 percent of the total amount of carbon dioxide in the United States can be attributed to buildings, 21 percent from homes and 17.5 percent from commercial uses. Buildings account for 12.2 percent of the total amount of water consumed per day in the United States. Considering these data’s, reducing the amount of natural resources buildings consume and the amount of pollution given off is seen as crucial for future sustainability, according to EPA. The environmental impact of buildings is often underestimated, while the perceived costs of green buildings are overestimated. A recent survey by the World Business Council for Sustainable Development finds that green costs are overestimated by 300 percent, as key players in real estate and construction estimate the additional cost at 17 percent above conventional construction, more than triple the true average cost difference of about 5 percent.

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Economics of Geography and Environment (G101)

Clean Technology: a greener aspect to development

The aims of Green Building
The concept of sustainable development can be traced to the energy (especially fossil oil) crisis and the environment pollution concern in the 1970s. The green building movement in the U.S. originated from the need and desire for more energy efficient and environmentally friendly construction practices. There are a number of motives to building green, including environmental, economic, and social benefits. However, modern sustainability initiatives call for an integrated and synergistic design to both new construction and in the retrofitting of an existing structure. Also known as sustainable design, this approach integrates the building life-cycle with each green practice employed with a design-purpose to create a synergy amongst the practices used. Green building brings together a vast array of practices and techniques to reduce and ultimately eliminate the impacts of buildings on the environment and human health. It often emphasizes taking advantage of renewable resources, e.g., using sunlight through passive solar, active solar, and photovoltaic techniques and using plants and trees through green roofs, rain gardens, and for reduction of rainwater run-off. Many other techniques, such as using packed gravel or permeable concrete instead of conventional concrete or asphalt to enhance replenishment of ground water, are used as well. While the practices, or technologies, employed in green building are constantly evolving and may differ from region to region, there are fundamental principles that persist from which the method is derived: Siting and Structure Design Efficiency, Energy Efficiency, Water Efficiency, Materials Efficiency, Indoor Environmental Quality Enhancement, Operations and Maintenance Optimization, and Waste and Toxics Reduction. The essence of green building is an optimization of one or more of these principles. Also, with the proper synergistic design, individual green building technologies may work together to produce a greater cumulative effect. On the aesthetic side of green architecture or sustainable design is the philosophy of designing a building that is in harmony with the natural features and resources surrounding the site. There are several key steps in designing sustainable buildings: specify 'green' building materials from local sources, reduce loads, optimize systems, and generate on-site renewable energy.

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Economics of Geography and Environment (G101)

Clean Technology: a greener aspect to development

The features of a green building:
Landscaping & design effectiveness The foundation of any construction project is rooted in the concept and design stages. The concept stage, in fact, is one of the major steps in a project life cycle, as it has the largest impact on cost and performance. In designing environmentally optimal buildings, the objective function aims at minimizing the total environmental impact associated with all life-cycle stages of the building project. Creating sustainable buildings starts with proper site selection. The location of a building affects a wide range of environmental factors - such as security, accessibility, and energy consumption, as well as the energy consumed by transportation needs of occupants for commuting, the impact on local ecosystems, and the use/reuse of existing structures and infrastructures. If possible, locating buildings in areas of existing development where infrastructure already exists and conserving resources by renovating existing buildings will help minimize a project's environmental footprint. Maximizing the green impact of site design and building infrastructure may be accomplished by considering energy implications during site selection and the

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Economics of Geography and Environment (G101)

Clean Technology: a greener aspect to development

design of building orientation. Improved grading and natural landscaping practices can help control erosion as well as reduce heat islands.

Energy Efficiency Green buildings often include measures to reduce energy use. To increase the efficiency of the building envelope, (the barrier between conditioned and unconditioned space), they may use high-efficiency windows and insulation in walls, ceilings, and floors. Another strategy, passive solar building design, is often implemented in low-energy homes. Designers orient windows and walls and place awnings, porches, and trees to shade windows and roofs during the summer while maximizing solar gain in the winter. In addition, effective window placement (day lighting) can provide more natural light and lessen the need for electric lighting during the day. Solar water heating further reduces energy loads. Onsite generation of renewable energy through solar power, wind power, hydro power, or biomass can significantly reduce the environmental impact of the building. Power generation is generally the most expensive feature to add to a building.

Water Efficiency Reducing water consumption and protecting water quality are key objectives in sustainable building. One critical issue of water consumption is that in many areas of the country, the demands on the supplying aquifer exceed its ability to replenish itself. To the maximum extent feasible, facilities should increase their dependence on water that is collected, used, purified, and reused on-site. The protection and conservation of water throughout the life of a building may be accomplished by designing for dual plumbing that recycles water in toilet flushing. Waste-water may be minimized by utilizing water conserving fixtures such as ultra-low flush toilets and low-flow shower heads. Point of use water treatment and heating improves both water quality and energy efficiency while reducing the amount of water in circulation. The use of non-sewage and

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Economics of Geography and Environment (G101)

Clean Technology: a greener aspect to development

greywater for on-site use such as site-irrigation will minimize demands on the local aquifer.

Materials Efficiency Building materials typically considered to be 'green' include rapidly renewable plant materials like bamboo (because bamboo grows quickly) and straw, lumber from forests certified to be sustainably managed, ecology blocks, dimension stone, recycled stone, recycled metal, and other products that are non-toxic, reusable, renewable, and/or recyclable (e.g. Trass, Linoleum, sheep wool, panels made from paper flakes, compressed earth block, adobe, baked earth, rammed earth, clay, vermiculite, flax linen, sisal, seagrass, cork, expanded clay grains, coconut, wood fiber plates, calcium sand stone, concrete (high and ultra-high performance, roman self-healing concrete , etc.) The EPA (Environmental Protection Agency) also suggests using recycled industrial goods, such as coal combustion products, foundry sand, and demolition debris in construction projects. Polyurethane heavily reduces carbon emissions as well. Polyurethane blocks are being used instead of CMTs by companies like American Insulock. Polyurethane blocks provide more speed, less cost, and they are environmentally friendly. Building materials should be extracted and manufactured locally to the building site to minimize the energy embedded in their transportation. Where possible, building elements should be manufactured off-site and delivered to site, to maximize benefits of off-site manufacture including minimizing waste, maximising recycling (because manufacture is in one location), high quality elements, better OHS management, less noise and dust.

Indoor Environmental Quality Enhancement The Indoor Environmental Quality (IEQ) was created to provide comfort, wellbeing, and productivity of occupants. The IEQ also addresses design and construction guidelines especially: indoor air quality (IAQ), thermal quality, and lighting quality.

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Economics of Geography and Environment (G101)

Clean Technology: a greener aspect to development

Indoor Air Quality seeks to reduce volatile organic compounds, or VOC's, such as microbial contaminants. Buildings rely on a properly designed HVAC system to provide adequate ventilation and air filtration as well as isolate operations (kitchens, dry cleaners, etc.) from other occupancies. During the design and construction process choosing construction materials and interior finish products with zero or low emissions will improve IAQ. Many building materials and cleaning/maintenance products emit toxic gases, such as VOC's and formaldehyde. These gases can have a detrimental impact on occupants' health and productivity as well. Avoiding these products will increase a building's IEQ. Personal temperature and airflow control over the HVAC system coupled with a properly designed building envelope will also aid in increasing a building's thermal quality. Creating a high performance luminous environment through the careful integration of natural and artificial light sources will improve on the lighting quality of a structure.

Reducing waste Green architecture also seeks to reduce waste of energy, water and materials used during construction. For example, in California nearly 60% of the state's waste comes from commercial buildings. During the construction phase, one goal should be to reduce the amount of material going to landfills. Well-designed buildings also help reduce the amount of waste generated by the occupants as well, by providing on-site solutions such as compost bins to reduce matter going to landfills. To reduce the impact on wells or water treatment plants, several options exist. "Greywater", wastewater from sources such as dishwashing or washing machines, can be used for subsurface irrigation, or if treated, for non-potable purposes, e.g., to flush toilets and wash cars. Rainwater collectors are used for similar purposes. Centralized wastewater treatment systems can be costly and use a lot of energy. An alternative to this process is converting waste and wastewater into fertilizer, which avoids these costs and shows other benefits. By collecting human waste at the source and running it to a semi-centralized biogas plant with other biological

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Economics of Geography and Environment (G101)

Clean Technology: a greener aspect to development

waste, liquid fertilizer can be produced. This concept was demonstrated by a settlement in Lubeck Germany in the late 1990s. Practices like these provide soil with organic nutrients and create carbon sinks that remove carbon dioxide from the atmosphere, offsetting greenhouse gas emission. Producing artificial fertilizer is also more costly in energy than this process.

Expenses of green building
The most criticized issue about constructing environmentally friendly buildings is the price. Photo-voltaics, new appliances, and modern technologies tend to cost more money. Most green buildings cost a premium of