# Energy System Engineering Aspects

Energy system is the engineering subject which study about energy sources, availability, Sustainability for large entity like a country. It is done by both engineering and financial ways to give them in optimum way to consumer with highly cost reflective way.

## Renewable Energy Systems

### Solar Energy – Renewable Energy System

Solar renewable Energy is the most easiest energy since 10000 years of use. Also At the surface of the Sun the intensity of the solar radiation is about 6.33×10^7 W/m2 (63MW/m2) and global mean solar power at earth’s surface is 170W/m².

#### Available Solar Energy Calculation

First the Solar Constant is the average extraterrestrial irradiance at the edge of the atmosphere. Isc= 1367 W/m2. Thus, the average irradiance incident on the earth’s surface (without the effects of the atmosphere) is 684 W/m2

#### Solar Maps

Insolationis a measure of solar radiation energy received on a given surface area in each time.

#### Concept of Solar Resource Map

Peak Sun Hours (PSH)

Solar map is providing monthly average daily total solar resource information on grid cells. Resource ready to a flat plate collector, such as a photovoltaic panel and oriented due to south at an angle from horizontal to equal to the latitude of the collector location are represent Insulation value.

#### Solar Power Technologies

• Solar Photo Voltaic (PV)
• Concentrated Solar Power (CSP)_ Thermal

#### Solar Cells are use for various type of applications

• General electric power applications
• Cars, ships, airplanes (soon) etc.
• Toys, watches, calculators
• Electric fences & protection systems
• Remote lighting systems
• Water pumping / Water treatment
• Emergency power
• Portable power supplies
• Satellites

### Wind Power – Renewable Energy system

Typical 600 kW wind turbine has rotor diameter of 43- 44 m , i.e.  a rotor area of some 1,500 square meters. Rotor area of wind turbine determines how much energy a wind turbine can harvest from the wind. Since the rotor area of wind turbine increases with the square of the rotor diameter, a turbine which is twice as large will receive 22 = 2 x 2 = four times as much energy.  we decide good location by considered for wind energy, an area needs to have average annual wind speeds of at least 12  miles per hour.

### Biomass Power

• Biomass is one of the major world fuel sources, especially in the third world, where it provides 40% of the energy requirements.
• At present due to biomass co firing in modern coal power plants with
• Biomass combustions are carbon free processes because resulting CO2 are previously capture by the plants being combust.
• At present due to biomass co‐firing in modern coal power plants with efficiencies up to 45% is the most cost‐effective biomass use for power generation.
• Due to feedstock availability issues, dedicate biomass plants for combined heat & power (CHP), are typically of smaller size and lower electrical efficiency compare to coal plants (30%‐34% using dry biomass, and around 22% for municipal solid waste).
• Biomass integrate gasification in gas turbine plant (BIG/GT) is not yet at commercial state, but integrated gasification combined cycles (IGCC) using black liquor (a by‐product from the pulp & paper industry) are already in use in this type
• Anaerobic digestion to produce bio gases are expanding in small, off‐grid applications. Bio refineries may open the door to combined, cost‐effective production of bio‐chemicals, electricity and bio fuels.
• Agricultural,Animal manure,wood wastes from forestry and industry, residues from food and paper industries, municipal green wastes, sewage sludge are the Biomass resource.
• Organic wastes & residues have been the major biomass source so far we have but energy crops are gaining importance and market share. With replanting, biomass combustion is a carbon‐neutral process as theCO2 emit has previously been absorb by the plants from the atmosphere.  Residues, wastes, bagasse are primarily use for heat & power generation.
• Also Sugar, starch and oil crops are primarily use for fuel production.

### Biogas – Renewable Energy system

• A mixture of Methane & Carbon dioxide
• Calorific value 21.5 MJ/kg (60% Methane)
• 1m3 of biogas is equivalent to 0.5 liters of diesel (approximately)
• From 1000 Tons of organic waste 36000 m3 due to  Biogas can be produced.

#### Renewable Energy due to Municipal Solid Waste (MSW)

• Fully Mixed up
• High Organic Content
• Smelly/Rotten

### Renewable Energy-Tidal Energy system

In addition of Renewable Energy of Tidal electricity is the end result of the interplay of the gravitational pull of the moon and, to a lesser extent, the sun, on the seas. Tidal strength historically entails erecting a dam throughout the opening to a tidal basin. The dam consists of a sluice that is open to permit the tide to drift into the basin; the sluice is then close, and as the sea stage drops the ensuing head can be use for electricity generation.

### Wave Energy – Renewable Energy system

Firstly Ocean waves are generate through wind passing over stretches of water . Also whole energy of waves breaking on the world’s coastlines is estimated at two the worlds coastlines is estimate at two to three million megawatts. Also In favorable locations, wave electricity density can common sixty five megawatts per mile of coastline. Ocean waves are generate with the aid of wind passing over stretches of water. But the complete strength of waves breaking on the world’s coastlines is estimate at two to three worlds coastlines is estimated at two to three million megawatts. In addition In favorable locations, wave electricity density can common sixty five megawatts per mile of coastline.

### Renewable Energy OETC – Energy system

Ocean thermal strength conversion, strength science that converts photo voltaic radiation to electric powered power due to OTEC structures use the ocean’s herbal thermal gradient (the truth that the ocean’s layers of water have unique temperatures) to pressure a power-producing cycle. Also If the temperature between the heat floor water and the bloodless deep water differs by way of about 20°C (36°F) the bloodless deep water differs by way of about 20 C (36 F), an OTEC device can produce a considerable quantity of power. The oceans are therefore a good sized renewable resource, with the workable to assist us produce billions of watts of electric powered power. In addition Each day, the oceans soak up ample warmness from the solar to equal the thermal power contained in 250 billion barrels of oil.

## Energy Sources In World – Energy system

Renewable energy sources in world are going to reduce day by day or going to not usable them in future and future generation is going to run out of energy .since our generation is going to use their share of the Energy Sources in world

### Non-Renewable Energy – Energy system

Energy sources used faster than can be reproduced energy sources.

As example : Coal – Oil – Natural Gas

### Renewable Energy Sources in world – Energy system

Energy sources which are continuously present as a feature of the environment (solar energy), or is continually reproduced the energy. Also Some forms are referred to as perpetual energy.

### What percent of fossil fuels are used?

•Fossil fuels supply 90% of world’s commercial energy.

1. Oil   40%
2. Coal   24%
3. Natural Gas  25%

### The difference between Resources & Reserves

1. Resource is the Naturally occurring substance of use to humans that can potentially be extracted using current technology.
2. Reserve is the Amount of a known deposit that can be economically extracted using current technology, under certain economic conditions. Also Reserve levels change as technology advances and new discoveries are made, and profit margins change.

### How is coal formed?

Also Plant material began collecting underwater, initiating decay, forming a spongy mass of organic material (peat). Due to geological changes the some of these swamps were covered by seas and covered with sediment. Pressure & heat over time transforms peat into coal with the time.

#### Types of extraction of Coal

There are Two main extraction methods:

Due to Surface Mining (Strip Mining) Removing overburden on top of a vein. Efficient but destructive.

Due to Underground Mining Minimises surface disturbance, but costly and dangerous. Black Lung Disease

#### Problems with Coal

1. Bulky due to causes some transport problems.
2. Black Lung Diseas due toMining creates dust pollution.
3. Mining accidents due to collapse of tunnels, malfunctioning machinery
4. Ecosystem damage/reclamation efforts
5. Burning releases pollutants (C and S).
6. Material Millions of tons released into atmosphere annually. Also Acid Rain:  Sulfur leads to acid mine drainage and acid deposition. Global warming:  Increased carbon dioxide

#### Coal Use Issues

Also Coal is most abundant fossil fuel.

At first Primarily used for generating electricity. Also Three Categories: Lignite §High moisture content Least desirable. Bituminous §Most abundant – Most widely used. Also Anthracite §Highest energy content Hard to obtain.

### Oil and Natural Gas

Oil and Natural Gas are accumulations of dead marine organisms bottom of the ocean floor were covered by sediments. Muddy rock gradually formed rock (shale) containing dispersed oil.This is how the oil pools began to form. Natural gas is often formed in oil. Organic substances became lighter, hydrocarbons more volatile than in oil.

#### Oil extraction

Primary Recovery

– oil rig drilling –Only removes 1/3 of a deposit.

Secondary Recovery

–Force water or gas into wells. With rising oil prices, more expensive and aggressive secondary recovery methods should be used.

### Oil Use Issues

•Processing

–Because oil comes from the soil, it is not in a suitable form for use and needs to be refined. vMultiple products can be made from a single barrel of crude oil.

•Oil Spills

–Accidental contamination only accounts for about 1/3 of the shipment’s oil contamination. 60% comes from routine shipping processes.

•More concentrated than coal, it burns cleaner and can be easily transported through pipes.

–Ideal for automobile use.

–Difficult to extract.

–Causes less environmental damage than coal mining.

### Natural Gas Use – Energy system

1. Drilling requirements similar to oil.
2. Difficult to transport: burned in oil fields.
3. As demand increases, new transportation methods will be developed and implemented. Liquefaction at 126o F v(1/600 volume of gas)
4. Least environmentally damaging fossil fuel. Almost no air pollution.
5. Use is increasing (45% from 1985-2003).

### Renewable Sources of Energy

Alternative energy sources currently account for almost 10% of the world’s total energy. See suggested that by 2050 these sources could cover half of the world’s energy needs.

1. Hydro power
2. Wind Turbines
3. Solar Cells
4. Biomass Fuels
5. Hydrogen Fuel

#### Hydro-electric Power

Hydroelectric power is created when the flowing water is collected and converted into electricity.

–The most common method is to dam a river and store water in a reservoir. Pump Storage Systems: Use two tanks that are separated by a significant height difference.

Currently supplies 15% of world’s electricity.

–China possesses 10% of world’s potential.

The construction of reservoirs causes considerable ecological and social damage.

1. Loss of farmland.
2. Community relocation.
3. Reduction of nutrient-rich silt leading to loss of wetlands. Three Gorges Dam on Yangtze River

#### Environmental Effects of Hydroelectric

1. Flooding of vast areas of land behind dams.
2. Prevention of fish migrations.
3. Trapping of silt.
4. Stops flow of nutrients downstream.
5. Fills in reservoir.
6. Mercury Accumulation
7. Decaying vegetation produces greenhouse gases.

### Tidal Power – Energy system

The daily rise and fall of sea level in relation to the coasts (tides) is the result of gravitational forces and the revolution of the earth. When water flows from a higher level to a lower level, it can be used to rotate a power generating turbine. Since the tidal changes are greatest near the poles and are accentuated in narrow bays and estuaries, suitable locations are limited.

#### Geothermal Energy Sources in world

In some areas, the molten material is close enough to the surface to heat the groundwater and form steam, drilled and collected.

1. Also Only practical in limited areas.
2. In addition California produces 40% of world’s geothermal electricity.
3. Also Can cause unpleasant odors and high mineral content leads to high maintenance. Corroded pipes and equipment.

### Wind Energy Sources in world

1. Also warm air becomes less dense and rises, cooler, denser, air flows in to take its place
2. Due to Wind technologies have developed during the last 10 – 15 years and 5MW units are in successful operation now. Larger units are on experimental operations.
3. At last Cost is becoming very competitive.

#### Wind Potential Problems

1. At first Steady, dependable wind source is critical. Wide open areas are most desirable.
2. Due to Can be hazardous to birds.
3. Due to Produce noise and visual pollution.
4. At last Vibrations can cause structural damage.

### Solar Energy Sources in world – Renewable energy sources

The sun’s daily energy is six hundred times greater than the energy that all the other energy sources generate together every day. The main problem as an energy source is its intermittent nature.

#### Three Major Use Categories – Renewable energy sources

•Passive Heating

1. Due to Sun’s energy is convert directly to heat and use at collection site.
2. Due to Drying

•Active Heating

1. Due to Sun’s energy convert into heat, but transport elsewhere to be used.
2. Due to Domestic Water Heating

•Electrical Generation

1. Due to Solar energy is transform into electrical energy.
2. Due to Photo voltaic, Solar Thermal

#### Biomass Conversion of Energy

1. Biomass is still the predominant form of energy use people in less-developed countries.
2. Also Account for 14% of world energy use.

#### Three Distinct Sources:

1. At First Municipal and Industrial Wastes
2. Due to Agricultural Crop Residue
3. Due to Energy Plantations

•Releasing chemical energy stored in biomass.

1. Due to Burned directly for heat.
2. Cause of Burned to produce electricity.
3. Due to Converted to alcohol or used to generate methane.
4. Due to Costs depends on type of technology used, size of the power plant, and the cost of biomass supply.

#### Fuel wood Energy

1. Also In less-developed countries, fuel wood has been major energy source for centuries.
2. Also Fuel wood is primary energy source for nearly half world’s population.
3. Due to intense population growth, an estimated 1.3 billion people cannot obtain enough firewood or use it faster than the regeneration rate.
4. Due to Source of air pollution and fly ash.

#### Solid Waste Energy to the world

1. Use municipal waste as an energy source.
2. Reduces landfill volume. Not economically profitable. Must be sort. Requires large, sustainable volume.
3. Produces air pollution. Chlorine-containing organic compounds.

#### Bio gas in World – Renewable energy sources

1. A mixture of Methane & Carbon dioxide
2. Calorific value 21.5 MJ/kg ( 60% Methane)
3. That of Diesel is 43 MJ/kg
4. 1m3 of biogas is equivalent to 0.5 liters of diesel

#### Hydrogen Economy for the world – Renewable energy sources

Due to Hydrogen is abundant and generates heat and pure water when it reacts with air. Also Hydrogen Fuel Cells Proton Exchange Membrane Fuel Cell Self-Sustaining Low Operating Temperature No Pollution §Successor to internal combustion engine.

## Energy Conversion Processes – Energy system

Energy Conversion Processes is discuss here.Saving energy is one of the words you hear more and more. Unfortunately, many places you’ll hear it will contain ads for marketing products or lifestyle habits that may have nothing to do with actual energy savings. To learn what the actual energy saving techniques are, you must begin to understand the underlying theory of saving.

### Understand energy savings

Also Energy saving is not about using limited resources for as long as possible. That would mean doing nothing more than prolonging a crisis until you run out of energy. Due to Conservation is the process of reducing the demand for a limited supply and enabling the reconstruction of the supply. Often the best way to do this is to replace the energy consumed with an alternative.

For fossil fuels, conservation may also include finding new ways to access the land supply so that commonly use oil fields are not completely depleted. This allows these fields to be filled more. Process that doesn’t takes place overnight. When you talk about replenishing natural resources, you are talking about reducing the excessive demand for supply in 100 years so that nature can recover.

1. A variety of energy conversion processes take place in nature.
2. Humans can perform a series of addition processes using a variety of devices (or processes).
3. Usually, the effect of a device creates more than one form of energy.
4. Many devices perform various conversion processes

e.g. : power plant – Coal Fired Power Plant, Nuclear Power Plant

### Thermodynamics

#### •First Law (Energy Conservation)

Energy can neither be create or destroy

–Energy can be utilize, not consume

#### •Second Law

–The quality of a certain amount of energy, i. H. The amount of work or action you can perform decreases each time energy is consumed.

•Also Energy we use is degrade into heat and then radiated out into space

### Engines – Energy system

•A consequence of the second law is that the perfect heat engine is impossible

Efficiency of ideal heat engine Efficiency e  = 1 – T2/T1

Where T1 is the temperature of the heat source (hot gas produce by fuel combustion

Where T2 is the surrounding air temperature

For a car, T1 = 2400K, T2 = 300K

So (Theoretical Efficiency) = 1 – 300/2400

= 0.88

#### Calorific Value – Energy system

•The calories of thermal units contain in one unit of a substance and release when the substance is burned

•Energy Density

What is the calorific value of the petrol = 10kWh/litre

Note density of the petrol assume to be 840kg/m3

#### Car Example – Energy system

What about the energy costs of making automobile fuel?
What about energy costs for auto manufacturing.

Referenace

1. page