INTRODUCTION

It is the collection of technological processes which are used to conserve the natural environment and resources inspite of making full use of those resources.

Sustainable technology requires the exploitation of the environment through creation and extraction of resources, and the exploitation of people through labor.

It aims to make the system environmental friendly.

It includes all technological processes utilizing substrates from nanoparticles upto huge particles.

Aims of sustainable technology:-

It uses less energy, fewer limited resources, do not deplete natural resources.

Sustainable technology do not directly or indirectly pollute the environment, and can be reused or recycled at the end of their useful life.

Drawbacks of sustainable technology:-

Sustainable technology may have high cost or maintenance requirements that make it unsuitable.

In this modern era of industrialization and competition it is very difficult to have hand on sustainable technologies as everybody wants its work to get completed in just in a blink of eye.

Sustainable technology may be divided into 4 main categories. These include:-

1) Green technology.

2) Nanotechnology.

3) Appropriate technology.

4) Renewable energy technology.

1) Green technology/ clean technology:-

Green technology or greentech or environment technology as envirotech or clean technology as cleantech is the application of the environmental science to conserve the natural environment and resources and to curb the negative impacts of human involvement. It works on 3R- reduce, reuse & recycle. Greentech involves all those technological processes which are beneficial for human beings taken in concern the environment. It includes following aspects:

a) Sustainable agriculture.b) Organic farming.c) Recycling.d) Water purification.e) Air purification.f) Sewage treatment.g) Environmental remediation.h) eGain forecasting.i) Energy conservation.Sustainable agriculture :- it is the practice of farming using principles of ecology, the study of relationships between organisms and their environment .It aims :-

Satisfy human food and fiber needs. Make the most efficient use of nonrenewable resources. Sustain the economic viability of farm operations. Enhance the quality of life for farmers and society as a whole.

b) Organic farming:- It is agriculture the form of agriculture that relies on techniques such as crop rotation, green manure, compost and biological pest control to maintain soil productivity and control pests on a farm. It excludes or strictly limits the use of manufactured fertilizers and pesticides, plant growth regulators such as hormones, livestock antibiotics, genetically modified food etc.

C) Recycling:- It is a worldwide phenomenon which is a basic application towards Greentech. It shows and encourages people to reuse items that can be reusable. Items like saving cans, paper, bottles etc are recycled for further use. It protects the environment and reduces pollution.

d) Water purification:- It is the whole idea of having dirt/ germ/ pollution free water flowing through the environment .In 2006, water pollution is estimated to cause 1.8 million deaths each year. Green tech options in water treatment include both community- scale and house hold- scale point of use (POU) designs. The most reliable way of water purification is to heat water to a rolling boil. Other techniques like, filtration, chemical disinfection, exposure to ultraviolet radiation, porous ceramic filtration etc are also used.

e) Air purification:- for air purification the basic and common green plants can be grown indoors to keep air fresh because all plants remove carbon dioxide and convert it into oxygen. The best examples are Dypsis lutescens, Sanseveria trfasciata and Epipremmum aureum.

f) Sewage treatment:- It is somewhat related to water purification . Sewage treatment purifies water of its pollution. The more the water is polluted; it’s not used for anything, the least polluted water is supplied to places. It may lead to concepts of various other concepts of environmental protection, sustainability etc.

Sewage treatment plant

g) Environmental remediation: is the removal of pollutants or contaminants for the general protection of the environment. This is accomplished by various chemical, biological and bulk movement methods, in conjunction with environmental monitoring.

Pit airbrush used in environmental remediation

h) eGain forecasting: It is a method using forecasting technology to predict the future weathers impact on a building by adjusting the heat based on weather forecast, the system eliminates redundant use of heat, thus reducing the energy consumption and the emission of greenhouse gases.

i) Energy conservation: It is the utilization of devices that require smaller amounts of energy in order to reduce the consumption of electricity. It involves:-

New solar technology:- it includes treated silicon solar cells. An untreated silicon solar cell only absorbs 67.4% of sunlight i.e., 1/3 rd of that sunlight is reflected away and thus unharvestable. After a silicon surface was treated with nanoengineered reflective coating, the material absorbed 96.21% of sunlight shone upon it. This technology could increase solar output by 20-30%.

New antireflective coating increases solar output

Tree power: - it defines about the trees that produce electricity. Researchers found that plants generate a voltage of upto 200 mill volts when one electrode is placed in a plant and other in the surrounding soil.

Scientists working on trees producing electricity

2) Nanotechnology

It is also known as nanotech and is the manipulating matter on an atomic and molecular scale. Generally, nanotechnology deals with structures sized between 1-100 nanometer.

Nanotechnology is very diverse, ranging from extensions of conventional device physics to completely new approaches based upon molecular self assembly.

i) Nanomaterials :-The properties of materials changes when its size decreases ,e.g.) the quantum size effect , where the electronic properties of

solids are altered with great reductions in particle size. However quantum size effect becomes dominant in nanometer size range typically at distances of 100 nanometers or less, the so called quantum realm.

Nanomaterial structure

ii) Nanoionics :- where fast transfer of ions take place.

iii) Nanomechanisms:- Mechanical properties of nanosystems are of interest in the nanomechnics research. When materials are reduced to nanomaterials they show different physical properties compared to what they exhibit at macro scale .e.g.) opaque substances become transparent (copper); stable materials turn combustible (aluminum); insoluble materials become soluble gold. Gold which is inert at normal scale turns chemical catalyst at nanoscales.Approaches of nanotechnology :

i) Bottom –up approach.

ii) Top-down approach.

i) Bottom-up approach :- This seek to arrange smaller components into more complex components . DNA nanotechnology utilizes the specificity of WATSON CRICK

base pairing to construct well defined structures out of DNA and other nucleic acids.

Nanotechnology aims to design molecules with well defined shape. E.g.) bis –peptides.

It involves concepts of supramolecular chemistry and molecular recognition to arrange single molecular components into some useful conformation.

Atomic force microscope tips can be used as a nonoscale”write head” to deposit a chemical upon a surface in a desired pattern in a process called dip pen.

Nanolithography : - this technique fits into the larger subfield of nanolithography.

Image of DNA biochip

ii) Top down approaches: It leads to the creation of smaller devices using larger ones.

Solid state silicon methods for fabricating microprocessors are now capable of creating features smaller than 100nm.

Giant mangetoresistance based hard drives are the examples of this. Solid state techniques can also be used to create devices known as

nanoelectromechanical systems or NEMS, which are related to microelectromechanical systems or MEMS.

In transmission electron microscopy focused ions beams can directly remove material, or even deposit material when suitable gases are applied at the same time.

Image of nanocrystal

Applications of nanotechnology:-

a) Nanocars.b) Bionanotechnology.c) Molecular nanotechnology.d) Nanorobotics.e) In industrial sector.f) Medical science.g) In daily use items.h) Electronics.

Implications / drawbacks:-

a) Untraceable weapons of mass destruction.

b) Nanocameras.c) Nanotoxivology.d) Nanoparticles kill useful bacteria.e) Effect of nanoparticles on animals.f) Effect of nanoparticles on humans.

Regulation:-

Tighter regulation of nanotechnology related to human health and safety risks is needed. Some agencies have taken control over it. Some agencies have taken control over it .Some regulatory road map for administrations are necessary to oversight. The nanoparticles being released during disposal, destruction and recycling, and recommended to fall under responsibility regimes. It is our responsibility to play a meaningful role in the development of these standards.

3) APPROPRIATE TECHNOLOGY:

It is the technology that is designed with special considerations to the environment, ethical, cultural, social, political and economical aspects of the community. With environmental and ethical goals in mind, claims their methods require fewer resources, are easier to maintain, and have less of an impact on the environment compared to techniques from mainstream technology which they contend is wasteful and environmentally polluting.

Appropriate technology founders:- It is supposed to commence from Mahatma Gandhi. E.f.Schumacher influenced by Gandhiji took it to international level. Steward Brand popularized it and contributed major role towards it.

Appropriate technology is divided into further types:-

Intermediate technology.

Soft technology.

Hard technology.

Intermediate technology :- Term was coined by E.F.Schumacher. It refers specifically to tools and technology that are significantly more effective and expensive than traditional methods.

Less expensive, easily affordable by poor class.

More compatible with the laws of ecology.

Gentle in its use and serves to human person.

Soft technology:- it deals with

Social structures, human interactive processes, and motivation technology.

It is the structure and process for social participation and action by individuals and groups in analyzing situations, making choice that brings about change.

Contribution of political parties and celebrations are against this.

Hard technology :- Engineering technology. Physical structures and machinery that meet a need defined by

a community and utilize the material at hand or readily available.

It can be built, operated and maintained by local people with limited outside assistance.

Related to economic goal.

Appropriate technology covers following fields:-

a) City construction :- Green building material. Building structures. Cost effectiveness. Public housing approach. Decrease costs of operations (heating, cooling) technology.

City constructed in according with appropriate technology

b) Energy :- It includes renewable energy technology and non renewable energy technology resources.

Photovoltaic (pv) solar panels. Human powered hand wheel generators. Zero emission generation methods. Bioethanol, biodiesel and straight vegetable oil can be appropriate,

direct biofuels in areas where vegetable oil is readily available and cheaper than fossil fuels.

Anaerobic digestion power plants. Biogas is another potential energy source when there is abundant

supply of waste organic matter. Animal excreta is also used for obtaining organic matter eg) urine.

c) Transportation :-

Megabus :- it is double decker than holds 79 persons in comfort. It gets 6-7miles/gallon ie) 474-553 pasengers/ gallon.

Megabus

Human powered vehicles :- it include ,bicycle , that provide human powered transportation at a lower cost of ownership than motorized vehicles.

Human powered vehicles

a) Sanitation:- Water born diseases are estimated to cause 1.8 million deaths each year, marking the importance of proper sanitation systems. Ecological sanitation is the major process dealing with human excreta. It works by incorporating following steps:-

i) Containments

ii) Sanitization

iii) Recycling

The objective is to protect human health and the environment while limiting the use of water in sanitation systems for hand washing only and recycling nutrients to help reduce the need for synthetic fertilizers in agriculture.

Composting toilets: they are the most environmental form of excrement disposal system. In fact toilet design follows the nutrients to be reused and is also cost effective.

Composting toilet Treatment ponds and constructed wetlands: - They consist mostly

of plants and therefore require only little power. Certain other options as slow sand filters, UVfilters may also be employed.

b) Food production: urban gardening, indoor cultivation, forest gardening are the methods of food production under appropriate technology. Crop production tools are best kept simple techniques. Tools can include animal- pulled plows, dibbers wheeled augers, kirpis, hoes. Greenhouses are also sometimes included.

c) Cooking: fossil (nonrenewable) and biofuels (renewable) for cooking cause more pollution. Other old methods are more wasteful and less effluent.

Solar cookers are appropriate to something depending on climate and cooking style. They are emission less and low cost.

Hot plates are 100% electrical, fairly low coast and are mobile. Rocket stoves and certain other wood stoves improve fuel efficiency,

and reduce harmful indoor air pollution.

Solar cooker used to cook food

d) Refrigeration :

Solar and thermal mass refrigerators reduce the amount of electricity required. Also they donot use haloalkanes but use heat pumps or mirrors instead.

The pot-in-pot refrigerator is an African invention which keeps things cool without electricity. It provides a way to keep food fresh for longer time.

Refrigerator based on appropriate technology

e) Healthcare: according to Global Health Council the use of professionally schooled doctors, the training of villagers to remedy in towns in developing world is encouraged. Trained villagers are able to eliminate80% of the health problems. Herbalist medicines are appropriate medicines, as they can be freely made at home and are almost as effective as their chemical counter parts.

4) RENEWABLE ENERGY TECHNOLOGY

It is that energy which can be replenished easily. For years 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. Renewable energy is critical to our fight against climate change. We simply must shift our world to a low- carbon economy and away from oil and coal. Experts suggest that there is a need renewable energy to replace fossil fuels now. Renewable energy technology tends to be located outside crowded urban areas, helping smaller, local economics which reducing reliance on fossil and foreign energy resources. Renewable energy carbon offset projects met the toughest industry standards and are third party verified to ensure the highest quality.

a) Bajaj Finserv Wind Project

Location: Maharastra, India Project type: Wind Energy Standard: Chicago Climate Exchange

Carbonfund.org supports the Bajaj Finserv Wind Project because it provides renewable electricity, supports local businesses and is a prime example of how wind projects can significantly contribute to a nation’s energy portfolio.

Bajaj Finserv Wind Project

b) Fujian Nanridao Wind Project of China

Location: Nanri Island of Putian City, Fujian Province of ChinaProject type: Wind Energy

The nineteen turbines that make up this wind project have a total generation capacity of approximately 16.15 megawatts. In addition, this project promotes sustainable development by expanding local employment opportunities.

Fujian Nanridao Wind Project of China

c) Gujarat Wind Projects

Location: Gujarat, IndiaProject type: Wind EnergyThe Aggregated Wind Projects of Gujarat have made it possible for 52 owners to combine their 65 wind turbines into a single project. Each of the turbines has a capacity between 0.35 megawatts and 1.5 megawatts and collectively, they produce 59 megawatts of renewable electricity.

Gujarat Wind Projects

d) Kalani Wind Farm

Location: Rajasthan, IndiaProject type: Wind EnergyThe Kalani Wind Farm was the first private wind turbine project to be constructed in the state of Rajasthan. This project consists of 12 turbines, each with a capacity of 0.23 megawatts, for a total output of 2.76 megawatts.

 

Kalani Wind Farm

e) Chino Basin Dairy Farm Biodigester

Location: Chino Basin, CaliforniaProject type: Waste-to-Energy BiodigesterThe Chino Basin Dairy Farm Biodigester Project generates clean electricity from local manure. Carbonfund.org helps this renewable energy project successfully reduce more than 8,000 tons of carbon dioxide each year and support local dairy farms.

Chino Basin Dairy Farm Biodigester

f) Freund’s Farm Dairy Methane Project

Location: East Cannan, ConnecticutProject type: Waste-to-Energy Biodigester

It helps to reduce heat-trapping methane emissions which in turn, lessen the impact of global climate change. Freund’s Farm installed a 62-foot anaerobic biodigester that receives approx 3,600 gallons of manure each day from 240 cows and reduces up to 1,200 tonnes of carbon dioxide equivalent emissions each year. Biodigesters capture methane generated by manure and transform it into a clean, renewable energy source.

Freund’s Farm Dairy Methane Project

g) Gardner Sanitary Landfill Methane Project

Location: Gardner, MassachusettsProject type: Methane Destruction

As landfills harbor methane from trash, the project destroys the landfill methane, which is approximately 23 times more potent as a greenhouse gas than carbon dioxide.

Gardner Sanitary Landfill Methane Project

h) Neria Small Hydroelectric Project

Location: Karnataka State of IndiaProject type: Hydroelectric EnergyAs a run-of-river hydroelectric project, this project provides a sustainable source of renewable energy that does not require the displacement of people nor a dam. The project is located near the famous Dharmasthala temple village on the River Neria.

Neria Small Hydroelectric Project

i) New Hope View Dairy Methane Project

Location: Homer, New YorkProject type: Methane Destruction

Carbonfund.org supports the New Hope View Dairy Methane Project because it helps to reduce heat-trapping methane emissions which in turn, lessen the impact of global climate change. Biodigesters essentially capture methane generated by manure and transform it into a clean, renewable energy source.

New Hope View Dairy Methane Project