Wind Energy Basics

Winds are caused by uneven heating of the atmosphere by the sun, the roughness of the Earth surface and Earth's rotation. Winds flow patterns are changed by the topography of land, water and plants. Modern wind turbines use this flow of air to generate electricity. Humans use this wind flow for various purposes e.g.: generating electricity, drying clothes, sailing.

Wind energy today is the cleanest and most reliable way to generate electricity. Wind power neither produces any toxic emissions nor any heat-trapping emissions that contribute to global warming.

The fact that wind energy is most widely available, abundant and increasingly cost-competitive energy resources, making it a viable alternative to fossil fuels that harm our health and threaten the environment .

How fast the wind blows, how often and when has an important role to play in power generation costs. Power output of wind turbines increases as the cube of wind speed. 

In other words, if the speed of the wind doubles, the production of electricity is increased about eight times. Thus, the winds with the higher speed are less expensive and easier to catch.

The term wind power describes the process by which wind is used to make the mechanical energy or electricity. Wind turbines convert the kinetic energy of wind energy into mechanical power.

This mechanical power may be used for certain activities (such as milling of rice or pumping water) or a generator can convert mechanical energy to electrical energy at home, business, schools and other facilities.

Advantages & Disadvantages Of Wind Energy

Excessive heating of earth due to burning of fossil fuels have forced people across the globe to generate power through wind. It is being used extensively in areas like USA, Denmark, spain, India and Germany. Like any other source of power generation, wind energy has its own advantages and disadvantages.

Advantages of Wind Energy:

1. Renewable Energy : Wind energy in itself is a renewable energy which means it can be produced again and again since it is available in plenty. It is cleanest form of renewable energy and is currently used many leading developed and developing nations to fulfill their demand for electricity.
2. Reduces Fossil Fuels Consumption : Dependence on the fossil fuels could be reduced to much extent if it is adopted on the much wider scale by all the countries across the globe. It could be answer to the ever increasing demand for petroleum and gas products.
3. Less Air and Water Pollution : Wind energy doesn't pollute at all. It is that form of energy that will exist till the time sun exists. It does not destroy the environment or release toxic gases.
4. Initial Cost : The cost of producing wind energy has come down steadily over the last few years. The main cost is the installation of wind turbines. Moreover the land used to install wind turbines can also be used for agriculture purpose.

Vertical Axis Wind Turbines

Rising sea levels and escalating pollution levels has generated worldwide interest and has given rise to new wind turbines designs. Wind turbines mainly are of two types: vertical axis(VAWT) and horizontal axis(HAWT). HAWT are the most common type of wind turbines built across the world. VAWT is a type of wind turbine which have two or three blades and in which the main rotor shaft runs vertically. They are however less frequently used as they are not as effective as HAWT.

The main difference between the VAWT and HAWT is the position of blades. In HAWT, blades are on the top, spinning in the air and are most commonly seen while in VAWT, generator is mounted at the base of the tower and blades are wrapped around the shaft. The main advantage of VAWT over HAWT is it's insenstivity to wind turbines and therefore can be mounted closer to the ground making it effective for home and residential purpose. Vertical turbines spin on the vertical axis and comes in various shapes sizes and colors. It's movement is similar to a coin spinning on the edge.

Here are some of the advantages of VAWT:

1. The turbine generator and gearbox can be placed lower to the ground making maintanence easier and lower the construction costs.
2. The main advantage of VAWT is it does not need to be pointed towards the wind to be effective. In other words, they can be used on the sites with high variable wind direction.
3. Since VAWT are mounted closer to the ground they are more bird friendly and down not dectroy the wildlife.
4. VAWT quiet, efficient, economical and perfect for residential energy production, especially in urban environments.

Despite these advantages VAWT's suffer from serious drawbacks. Let's have a look at some of them:

1. As the VAWT are mounted closer to the ground, less wind speed is available to harness which means less production of electricity.
2. VAWT are very difficult to erect on towers, which means they are installed on base, such as ground or building.
3. Another disadvantage of VAWT is the inefficiency of dragging each blade back through the wind.

Introduction

Geothermal energy as earlier has been explained is the energy that lies within the earth. It is one of the most renewable source of energy which is never going to extinct and can be found almost anywhere - as far away as remote deep wells or may be closer to your home. Energy inside the earth is never going to deplete and will remain as a source of heat, for millions and millions of years and we can harness that energy that is going to be cheaper and can help us to reduce our dependence on fossil fuels and global warming and public health issues that result from their use.

How Geothermal Energy Works?

Our planet, Earth, is covered with the is covered with the thick outer shell called crust, which is made up of many different rock layers and plates whose components keeps on shifting and changing. Under Earth's crust, there is a layer of hot and molten rock called magma. Heat is continually produced there, mostly from the decay of naturally radioactive materials such as uranium and potassium. The amount with in the earth's surface contains 50,000 times more energy than all the oil and natural gas resources in the world. So, due to extreme heat inside the earth these rocks start developing cracks and release energy in the form of water or heat on to the earth's surface. To get that heat, water is pumped down an "injection well". Then it filters through the cracks in the rocks where they are at a high temperature. The water then returns via the "recovery well" under pressure in the form of steam. That steam is captured and is used to drive electric generators.

Geothermal Energy

The benefits of geothermal energy in the form of heating and cooling has been discovered by thousands of people worldwide who swear by the comfort it provides and the simplicity of its operation. Geothermal energy has proven themselves over the decades and several manufacturers and many contractors provide the competition you need to ensure quality installation and service at a fair price.

Geothermal Heating

A Geothermal heat pump is used to harness geothermal energy from inside the earth to heap our homes or to use that heat for industrial purposes. Geothermal heat pumps are built on the same basic premise as regular heat pumps. The difference is that the geothermal type draws heat from the earth instead of from outdoor air. The heat from the earth is considered to be stable and even. In addition to providing heating for your home, this type of energy can also provide air conditioning and in most cases, hot water.

In the winter, this process is reversed. The heat pump extracts heat from the relatively warm ground, usually warmer than the outdoor cold air, and pumps this heat into the conditioned space. This natural form of heating can also help improve humidity control by maintaining about 50% relative indoor humidity, making geothermal heat pumps very helpful in humid climates.

Geothermal Cooling

Geothermal cooling is a process by which shallow ground is utilized within a system to regulate temperature. By creating an earth loop of piping through the area outside your home, under the frost line, you can use this for cooling your home. During the summer you will remove the heat from your home and distribute it back into the earth loop outside your home. In the summer, the heat pump extracts heat from the conditioned space and sends it out to the earth loop to warm the relatively cool ground, or pond. This stable temperature is harnessed, using a geothermal device, to draw heat energy out of a system and thus transfer the cool temperatures into a warmer area.

Geothermal Power Plant

The earth's crust is a rich source of energy and fossil fuels are only part of the story. Thermal energy or heat is stored deep inside the earth. To put it in perspective, the heat in the upper ten kilometers of the Earth's crust is 50000 times the energy of all oil and gas reserves in the world!

The word "geothermal" literally means "Earth" plus "heat. Geothermal Resources is the largest source of energy worldwide and used by people for centuries.

This is a renewable resource and can be produced over and over again for years to come since earth has abudant amount of heat energy stored inside it, therefore it will not disrupt the ecological balance of our planet.

Geothermal power plants operating around the world are proof that the heat inside the earth is easily converted to electricity in geologically active areas.

Many municipalities, companies, universities and government agencies in the western United States fetch directly to the hot water from underground reservoirs. For owners of a house or building anywhere in the United States, the emergence of geothermal heat pumps brings the benefits of geothermal energy at their doorstep.

Deep underground there are rivers just like on the surface. They are really hot, as the magma is close to the river or around them, warming the surface of the rock.

Advantages & Disadvantages Of Geothermal Energy

As our reliance on fossil fuels have started to increase, geothermal energy is seen as the new source of power generation by digging out the heat stored inside the earth. Though not used fully due to factors such as location and high costs but in the years to come when fossil fuels would start to diminish, it will turn out to be the cheapest source of power generation. Geothermal energy suffers from its own advantages and disadvantages as described below.

Advantages of Geothermal Energy:

1. Significant Cost Saving : Geothermal energy generally involves low running costs since it saves 80% costs over fossil fuels and no fuel is used to generate the power.
2. Reduce Reliance on Fossil Fuels : Dependence on fossil fuels decreases with the increase in the use of geothermal energy. With the sky-rocketing prices of oil, many countries are pushing companies to adopt these clean sources of energy.
3. Environmental Benefits : Being the renewable source of energy, geothermal energy has helped in reducing global warming and pollution. Moreover, Geothermal systems does not create any pollution as it releases some gases from deep within the earth which are not very harmful to the environment.
4. Direct Use : Since ancient times, people having been using this source of energy for taking bath, heating homes, preparing food and today this is also used for direct heating of homes and offices.
5. Job Creation and Economic Benefits : Geothermal energy on the other hand has created many jobs for the local people.