HARVESTING ENERGY Sahil Khanna Samridhi Nanda

Prabhdeep Singh Pooja Khanna Shaminder Saini Shareen Aulakh

8L

Contents

• Introduction• Energy Forms• Solar Energy• Wind Energy• Bio Energy• Geothermal Energy• Water Energy• Tidal Energy

Introduction

The Real Scenario

Consequences

Yes, It Can Happen

What If?

• We have been meeting up our daily needs with the help of various non-renewable sources like coal, petroleum, nuclear energy and many more but have you ever imagined what will happen if they all go extinct.

Will it be able to satisfy our next generations with minimum resources?

Will we have enough electricity or petrol to run our houses/industries and cars?

Will it be possible to survive in such surroundings which will be full of poisonous gases and smoke?

Will basic necessities like potable water and shelter would be available in abundance?

But Yes, There is a Solution

• Energy from SUN, WATER, WIND, BIOMASS, GEOLOGY and TIDES can help us to tackle the increasing energy problems in the world. Because they are:

Free Non Polluting Never Ending Lifetime Services in return

of a small investment.

Solar Energy

• Solar energy, radiant light and heat from the sun, has been harnessed by humans since ancient times.

• Solar energy is widely available, free and pollution free.

How much Solar Energy?

The surface receives about 47% of the total solar energy that reaches the Earth. Only this amount is usable.

Putting Solar Energy to Use

Solar Energy can be utilized in various ways which includes: Water Heating Cooking Solar Cells & Panels Water Treatment

Water Heating using Solar Energy

• Two methods of heating water: passive (no moving parts) and active (pumps).

• In both, a flat-plate collector is used to absorb the sun’s energy to heat the water.

• The water circulates throughout the closed system due to convection currents.

• Tanks of hot water are used as storage.

Heating Water: Active System

Active System uses antifreeze so that the liquid does not freeze if outside temp. drops below freezing.

Cooking with Solar Energy

• Solar cookers use sunlight for cooking and drying .

• Three types: Box cookers, panel cookers and reflector cookers.

• Solar cookers use no fuel, which means that their users do not need to fetch or pay for firewood, gas, electricity, or other fuels.

Solar Cells & Solar Panels

• A solar cell (also called photovoltaic cell or photoelectric cell) is a solid state electrical device that converts the energy of light directly into electricity by the photovoltaic effect.

• A solar panel is a packaged interconnected assembly of solar cells, also known as photovoltaic cells.

• The solar panel can be used as a component of a larger photovoltaic system to generate and supply electricity in commercial and residential applications.

• They are widely used in Calculators, watches, Traffic lights and spacecrafts(SKYLAB Space Laboratory and International Space Station).

Water Treatment

• Solar distillation can be used to make saline or brackish water potable.

• Solar water disinfection (SODIS) involves exposing water-filled plastic polyethylene terephthalate (PET) bottles to sunlight for several hours.

• Exposure times vary depending on weather and climate from a minimum of six hours to two days during fully overcast conditions.

• Solar energy may be used in a water stabilisation pond to treat waste water without chemicals or electricity.

Advantages & DisadvantagesAdvantages:• Non polluting: no noise, no harmful or unpleasant emissions or smells. • Very reliable: most solar panels have a 25 year warranty and even a

longer life expectancy (the theory is they could last 100 to 125 years). • Solar modules over their lifetime produce more power per gram of

material than nuclear power but without the problem of large volumes of environmentally hazardous material.

• Solar Power is a renewable energy source. It is a resource that cannot be used up by us using it.

Disadvantages:• Sun does not shine consistently.• Solar energy is a diffuse source. To harness it, we must concentrate it

into an amount and form that we can use, such as heat and electricity.• Addressed by approaching the problem through: 1) collection, 2) conversion, 3) storage.

WIND ENERGY

• All renewable energy (except tidal and geothermal power), ultimately comes from the sun

• The earth receives 1.74 x 1017 watts of power (per hour) from the sun• About one or 2 percent of this energy is converted to wind energy(which is

about 50-100 times more than the energy converted to biomass by all plants on earth

• Differential heating of the earth’s surface and atmosphere induces vertical and horizontal air currents that are affected by the earth’s rotation and contours of the land to WIND.~ e.g.: Land Sea Breeze Cycle

Why we need wind energy?

Cost CompetitivenessCost Competitiveness

Environmental Awareness/

Government Initiatives

Environmental Awareness/

Government Initiatives

Energy SecurityEnergy Security

Increased Electricity Demand

Increased Electricity Demand

• Cost per Kwh of wind generation decreased from US$ 0.38 in early 80s to present US$ 0.03-0.06, at excellent wind sites (1)

• Rising Oil &Gas prices makes Wind Energy cost competitive

• Cost per Kwh of wind generation decreased from US$ 0.38 in early 80s to present US$ 0.03-0.06, at excellent wind sites (1)

• Rising Oil &Gas prices makes Wind Energy cost competitive

• Kyoto Protocol Implementation - Carbon-dioxide emission to reduce by 5.2% of 1990s levels, by 2012

• Implementation of Renewable Portfolio Standard requires minimum percentage of power generation from Renewable Energy

• Kyoto Protocol Implementation - Carbon-dioxide emission to reduce by 5.2% of 1990s levels, by 2012

• Implementation of Renewable Portfolio Standard requires minimum percentage of power generation from Renewable Energy

• Price volatility of Oil &Gas have increased focus on Renewable Energy

• Price volatility of Oil &Gas have increased focus on Renewable Energy

• Global Electricity Consumption expected to double between 2002 & 2030(2)

– higher growth in India and China• Wind Energy’s contribution expected to increase from 0.2% in

2002 to 3% in 2030 (3)

• Global Electricity Consumption expected to double between 2002 & 2030(2)

– higher growth in India and China• Wind Energy’s contribution expected to increase from 0.2% in

2002 to 3% in 2030 (3)

Windmill

• A windmill is a machine which converts the energy of wind into rotational energy by means of vanes called sails or blades .

• A Windmill captures wind energy and then uses a generator to convert it to electrical energy.

• When designing a windmill, one must decide on the size of the turbine, and the size of the generator

Wind Turbines

LARGE TURBINES:• Able to deliver electricity at lower cost than smaller turbines, because

foundation costs, planning costs, etc. are independent of size.• In areas where it is difficult to find sites, one large turbine on a tall tower

uses the wind extremely efficiently.• Well-suited for offshore wind plants.

SMALL TURBINES:• Local electrical grids may not be able to handle the large electrical output

from a large turbine, so smaller turbines may be more suitable.• High costs for foundations for large turbines may not be economical in

some areas.• Landscape considerations

A Large Wind Turbine Small Wind Turbines scattered over a field

India Wind Energy Use

The installed capacity of wind power in India is 13065.37 MW. Wind power accounts for 6% of India's total installed power

capacity, and it generates 1.6% of the country's power. Mainly spread across Tamil Nadu (4906.74 MW), Maharashtra

(2077.70 MW), Gujarat (1863.64 MW), Karnataka (1472.75 MW), Rajasthan (1088.37 MW), Madhya Pradesh (229.39 MW), Andhra Pradesh (136.05 MW), Kerala (27.75 MW), Orissa (2MW), West Bengal (1.1 MW) and other states (3.20 MW).

India is 5th largest wind energy producer in the world.

Advantages

• The wind blows day and night, which allows windmills to produce electricity throughout the day. (Faster during the day)

• Energy output from a wind turbine will vary as the wind varies, although the most rapid variations will to some extent be compensated for by the inertia of the wind turbine rotor.

• Wind energy is a domestic, renewable source of energy that generates no pollution and has little environmental impact. Up to 95 percent of land used for wind farms can also be used for other profitable activities including ranching, farming and forestry.

Disadvantages

Main disadvantage regarding wind power is down to the winds unreliability factor. In many areas, the winds strength is too low to support a wind turbine or wind farm.

Wind turbines generally produce allot less electricity than the average fossil fuelled power station, requiring multiple wind turbines to be built in order to make an impact.

Wind turbine construction can be very expensive and costly to surrounding wildlife during the build process.

The noise pollution from commercial wind turbines is sometimes similar to a small jet engine. This is fine if you live miles away, where you will hardly notice the noise, but what if you live within a few hundred meters of a turbine? This is a major disadvantage.

Bio Energy

• Bioenergy is renewable energy made available from materials derived from biological sources.

• It basically includes Biomass which is any organic material which has stored sunlight in the form of chemical energy. As a fuel it may include wood, wood waste, straw, manure, sugarcane, and many other byproducts from a variety of agricultural processes.

Solid Biomass

Biomass is material derived from recently living organisms, which includes plants, animals and their by products. Manure, garden waste and crop residues are all sources of biomass. It is a renewable energy source based on the carbon cycle, unlike other natural resources such as petroleum, coal, and nuclear fuels.

Bio Gas

A mixture of methane and carbon dioxide.

CH4

CO2

Methane or ‘swamp gas’, produced naturally in swampy

ponds

How is Biogas Made?

Bio-Energy Uses Biogas is a fuel used as an energy source for light, heat or movement

Advantages and Disadvantages

ADVANTAGES

help to manage the marsh gas pollution

improve the air quality

recycle rubbish

no greenhouse emission

reduction of air pollution and acid rain

DISADVANTAGES

storage problem (for recycled material)

cost for transporting and transferring

Geothermal Energy

• Geothermal energy- energy that comes from the ground; power extracted from heat stored in the earth From hot springs, geothermal energy has been used for bathing since Paleolithic times and for space heating since ancient Roman times, but it is now better known for electricity generation. Worldwide, about 10,715 megawatts (MW) of geothermal power is Online in 24 countries.

Why we use geothermal energy?

• It is renewable • It doesn’t cause pollution • Owners of buildings using geothermal have cut 25 to 50

percent off their utility bills. • No cooling towers, rooftop units, or individual room air

conditioning units are needed, so buildings and schools using geothermal systems look better.

• There is no fire hazard and no outside equipment that could potentially hurt kids.

Categories of Geothermal Resources

• Hot Water Reservoirs: geothermally heated underground water.

• Natural Steam Reservoirs: Instant steam but they are very rare

• Geopressurized Reservoirs• Normal Geothermal Gradient• Hot Dry Rock• Molten Magma

How geo thermal works?

Conventional Uses of Geothermal Energy

• A Tourist Attraction - come sit in our hot springs with people you don't know

• As a direct source of space heating

• As an instant steam generating facility to spin a turbine

• There are production sites in New Zealand, Iceland and, of course, California

Geothermal energy in India

India has reasonably good potential for geothermal; the potential geothermal provinces can produce 10,600 MW of power.

But yet geothermal power projects has not been exploited at all, owing to a variety of reasons, the chief being the availability of plentiful coal at cheap costs.

Potential Sites:• Puga Valley (J&K)• Tatapani (Chhattisgarh)• Godavari Basin Manikaran (Himachal Pradesh)• Bakreshwar (West Bengal)• Tuwa (Gujarat)• Unai (Maharashtra)• Jalgaon (Maharashtra)

Advantages• When a power station harnesses geothermal power in the

correct manner, there are no by products, which are harmful to the environment. Environmentalists should be happy about that!

• There is also no consumption of any type of fossil fuels. In addition, geothermal energy does not output any type of greenhouse effect. After the construction of a geothermal power plant, there is little maintenance to contend with. In terms of energy consumption, a geothermal power plant is self-sufficient.

• Another advantage to geothermal energy is that the power plants do not have to be huge which is great for protecting the natural environment.

Disadvantages• There are several disadvantages to geothermal energy.

First, you cannot just build a geothermal power plant in some vacant land plot somewhere. The area where a geothermal energy power plant would be built should consist of those suitable hot rocks at just the right depth for drilling. In addition, the type of rock must be easy to drill into. It is important to take care of a geothermal site because if the holes were drilled improperly, then potentially harmful minerals and gas could escape from under ground. These hazardous materials are nearly impossible to get rid of properly.

• Pollution may occur due to improper drilling at geothermal stations. Unbelievably, it is also possible for a specific geothermal area to run dry or lose steam.

Water Energy

• Water energy is a renewable energy source because it relies on the supply of water, a product on our planet that we have infinite supply of. When water flows or falls, it creates water energy, and this energy source is quickly becoming the most widely used form of renewable energy. While most dams are created to prevent flooding and to provide irrigation, there are some dams that are mainly used for water energy purposes.

How It Can Be Done?

Capturing runoff from rooftops

Capturing runoff from local catchments

Capturing seasonal floodwaters from local streams

Conserving water through watershed management

How Can Water Harvesting Help?

• Provide drinking water• Provide irrigation water• Increase groundwater recharge• Reduce storm water discharges, urban floods

and overloading of sewage treatment plants• Reduce seawater ingress in coastal areas.

How water can be harvested?

Rural scenario

Our ancestors had learnt to harvest water in number of ways:They harvested the rain drop directly. From rooftops, they collected water and stored it in tanks built in their courtyards. From open community lands, they collected the rain and stored it in artificial wells. They harvested monsoon runoff by capturing water from swollen streams during the monsoon season and stored it various forms of water bodies. They harvested water from flooded rivers.

How water can be harvested?

Urban scenarioThe total amount of water that is received in the form of rainfall over an area is called the rainwater endowment of the area. Out of this, the amount that can be effectively harvested is called the water harvesting potential. Water harvesting potential = Rainfall (mm) x Collection efficiency The collection efficiency accounts for the fact that all the rainwater falling over an area cannot be effectively harvested, because of evaporation, spillage etc. Factors like runoff coefficient and the first-flush wastage are taken into account when estimated the collection efficiency.

Rainwater harvesting from rooftop catchments

• Rooftop catchments: In the most basic form of this technology, rainwater is collected in simple vessels at the edge of the roof. As the rooftop is the main catchment area, the amount and quality of rainwater collected depends on the area and type of roofing material. Reasonably pure rainwater can be collected from roofs constructed with galvanized corrugated iron, aluminum or asbestos cement sheets, tiles and slates, although thatched roofs tied with bamboo gutters and laid in proper slopes can produce almost the same amount of runoff. Roof catchments should also be cleaned regularly to remove dust, leaves and bird droppings so as to maintain the quality of the product water.

Rainwater Harvesting from rooftop catchments

Rainwater harvesting from collection devices

Storage tanks: Storage tanks for collecting rainwater harvested using guttering may be either above or below the ground. Precautions required in the use of storage tanks include provision of an adequate enclosure to minimize contamination from human, animal or other environmental contaminants, and a tight cover to prevent algal growth and the breeding of mosquitoes. Open containers are not recommended for collecting water for drinking purposes.

Rainwater Harvesting from collection devices

Advantages

• Makes use of a natural resource and reduces flooding, storm water runoff, erosion, and contamination of surface water with pesticides, sediment, metals, and fertilizers

• Excellent source of water for landscape irrigation, with no chemicals such as fluoride and chlorine, and no dissolved salts and minerals from the soil

• Home systems can be relatively simple to install and operate May reduce your water bill Promotes both water and energy conservation

Disadvantages

• Limited and uncertain local rainfall• Can be costly to install.• Requires some technical skills to install and provide

regular maintenance.• Certain roof types may seep chemicals, pesticides,

and other pollutants into the water that can harm the plants.

• Rainwater collected during the first rain season is generally not needed by plants until the dry season. Once catchment is full, cannot take advantage of future rains.

Tidal Energy

• Tidal energy, is a form of hydropower that converts the energy of tides into electricity or other useful forms of power.

• Tidal power has potential for future electricity generation as tides are more predictable than wind energy and solar power.

Tides

• Tides generated by the combination of the moon and sun’s gravitational forces

• Greatest affect in spring when moon and sun combine forces

• In order to be practical for energy production, the height difference needs to be at least 5 meters

• Only 40 sites around the world of this magnitude

• Overall potential of 3000 gigawatts

How Tidal Energy Works?

Generating Method

• Tidal stream generatorTidal stream generators (or TSGs) make use of the kinetic energy of moving water to power turbines, in a similar way to wind turbines that use moving air.

• Dynamic tidal powerDynamic tidal power (or DTP) is a theoretical generation technology that would exploit an interaction between potential and kinetic energies in tidal flows. It proposes that very long dams be built from coasts straight out into the sea or ocean, without enclosing an area. Tidal phase differences are introduced across the dam, leading to a significant water-level differential in shallow coastal seas – featuring strong coast-parallel oscillating tidal currents such as found in the UK, China and Korea. The world's first commercial-scale and

grid-connected tidal stream generator – SeaGen – in Strangford Lough.

• Tidal barrage

Tidal barrages make use of the potential energy in the difference in height (or head) between high and low tides. Barrages are essentially dams across the full width of a tidal estuary.

Advantages

• No pollution• Renewable resource• More efficient than wind because of the density of water• Predictable source of energy vs. wind and solar • Second generation has very few disadvantages

Does not affect wildlife Does not affect silt depositsLess costly – both in building and maintenance

• Tidal energy does not depend on the weather.

Disadvantages

Presently costly: Expensive to build and maintain.A 1085MW facility could cost as much as 1.2 billion

dollars to construct and runTechnology is not fully developed

Barrage style has environmental affects Such as fish and plant migration Silt deposits Local tides change- affects still under study

One day we will have to get up from our slumber...and bear the consequences of our

present habits …. That would be the day we will realize the importance of the non-renewable

resources.So Let the day be today than tomorrow!

To avoid their depletionPromote Use Of the renewable sources of

energy and harvest them in a better way which can prove to be helpful not only to us

but also to the coming generations.

Thank You