Charles Blaine asked:


There has been a lot of talk lately about renewable energy sources, but not everyone actually knows what they are or how they work. Solar Energy is certainly one of those types of renewable energy that has a little mystery surrounding it. So, What is Solar Energy?

It is actually the energy that is created from the sun. Specifically, the light and the heat from the sun are the primary components of Solar Energy. The truth is that this type of technology has been around since the ancient ages, but as the years have passed, our technology has continued to improve. Sadly, the other brutal truth is that to this day we are only utilizing a small fraction of the power that is available from Solar Energy.

There are basically two different types of technologies that can harness Solar Energy: Passive Solar and Active Solar. They are called this due to how the sun’s rays are captured and processed. Passive solar capture is basically where you allow the sun’s rays to simply do their job. Often you will choose to have a building positioned so that it is in the line of the sun’s rays. From there, the sun’s rays will hit the building, which is made of energy efficient materials so that the sun will positively affect the building. However, active solar collection is the complete opposite of this. With active solar, you will use solar panels or solar thermal collectors to harness the power in the sun’s rays. These active solar technologies will convert this energy into electricity that you can then use to power your home.

Often you will see solar panels in big groups in very sunny places where business are trying to harness that power. However, the truth is that you do not have to be a big business to get that solar power. You also do not have to live in a place where the sun never stops shining to take advantage of it. In fact, anyone can start to take advantage of Solar Energy. Perhaps the easiest and best way to do this it to install solar panels onto your property. There is a misconception that solar panels are incredibly expensive. The truth is that for under $200 you can build your own solar panel. From there you will be able to supplement your homes electricity with the electricity that you are creating on your own. This will effectively start to reduce your energy costs.

Additionally, if you happen to be one of the lucky ones that live in a perpetually sunny place you may be able to create quite a bit of Solar Energy. If you can start creating so much energy that you start to have a surplus, you can actually start to make some money. In many cases, your power company will want to buy that extra energy from you. There is a great probability that your $200 investment could result in the elimination of your electric bill as well as a new source of income. What could be better than that?



Sally

Donald Whitehead asked:


Utilizing wind power and solar energy or the power coming from the sun’s rays has many benefits. Let us take a closer look on each of them.

•Solar energy saves money.

In 2006, we saw the highest jump on residential electric rate. In some areas of the country, as

much as a 60% increase was seen. Some cities in the state of Florida experienced an increase just this month (Jan-09) to start out the new year with. Many experts agree that the trend will likely continue in the years to come. This means that you have to pay larger sums of cash to sustain your monthly electric consumption. However by producing your own power, with the use of eitherwind power, solar energy or both you can prevent paying the high cost of energy – especially now when energy prices Keep fluctuating. Should American households switch to other types of alternative energy the nation’s spending on imported oil will diminish greatly.

•Both Wind Power and Solar Energy are environmentally-friendly resources.

The issue of global warming is a serious problem and it can not go away on it’s own. It is a Global concern which means that people all over the world need to take part in it’s recovery. The use of renewable resources, such as the ones in this article is a fantastic way for everyone to take part in doing their share to help save this planet, Using these two resources will have a great impact on our planet recovering from sustained damage already done if it were a worldwide effort. They are both sustainable and renewable unlike gas, coal and oil that most utility companies use. They do not produce any byproducts so they can’t pollute the air or do any harm whatsoever. Since they don’t emit greenhouse gases, they simply can’t contribute to global warming. Using wind power and or solar energy reduces demand for fossil fuel and reduces the nation’s dependence on foreign energy sources.

•Government gives incentives to those who use alternative forms of energy.

Many people are still discouraged to install these remarkable marvels because of various reasons. Costs is one reason, procrastination is another one and ignorance, not having a full understanding of just how effective this technology really is and staying in the dark ages of evolution and not excepting the giant step that it has made in progression.

Some states like California offers federal tax credits as much as $2000 and up front rebates that covers 20% to 30% of the total system cost for systems that are required to be installed by contracted companies in this field rather than being able to take full advantage of DIY offers where home owners who are capable of installing their own systems via wind power generator and solar energy kits that can be purchased for as little as $100-200 dollars. These type of kits also comes with very explicit instructions in both text and video tutorials plus support. These types of offers are relatively good considering the substantial increase of energy costs in recent years. They are very practical when it comes to just how much money they can actually save home owners in other wise month to month high power bill expenses. Along with tax credits home owners can also expect substantial property value increases too!

Note: Due to the increasing number of households who want to switch into alternative forms of

energy, the incentive levels decline. Check with your state government for the rates it offers if you are thinking about making a switch.

•Wind Power and Solar Power systems alike are dependable and require little or no

maintenance. Wind Power systems are typically windmills/wind turbines that have built in generators mounted right behind the propellers which are powered by the wind and as they spin generates electrical current which goes through inverters to adjust the current as it is saved in batteries for use to power homes or any appliance, whatever the intention of construction was for. Applications for usage is not limited.

Photovoltaic (PV) cells or solar panels that are used in solar power systems are capable of providing electricity also. The only difference between solar and wind is solar gets it’s power from the sun and wind gets it power from generators which are mounted inside windmills. Neither require little or no maintenance. Solar panels  like wind power generators lasts for 20 years ar more before needing to be replaced. Both are excellent resources for sustained reliability. Generally wind power and solar energy systems are installed together for a more consistent, more reliable energy resource. When the wind isn’t blowing the sun can charge the solar panels and when the sun is down and the wind should be blowing the wind generator can help in the power production process.

This article MUST NOT be changed or altered in any way. ALWAYS include the resource box with the article when you publish it.  You may publish this article on your blog or website, you can email it to your subscribers and submit it to the various online article directories.

All Rights Reserved (c) Copyright 2008 Solarenergycure.com



Luis

Brennan Howe asked:


Many Americans have decided to become more energy independent, and want to play a part in avoiding a very foreseeable energy crisis. They’ve decided to go solar. Creating a solar powered home is an endeavor that requires an initial investment, but the costs are being lowered everyday. Solar power provides long term benefits. Not just for the home owner, but the environment too.

Now that solar power is more efficient, you can reduce or even eliminate your electric bill, increase your home’s value and contribute to a cleaner environment, all at the same time. It’s a great time to join the move to renewable energy resources, and the perfect time to take advantage of the generous government and local utility financial incentives that can cut thousands of dollars off the price. And now that solar power is becoming even more main stream, it is growing in accessibility. Manufacturers of solar powered products have realized the potential for a solar age, and are creating new options for those who are considering a solar powered lifestyle. If you are ready to step into the solar age, you are probably wondering how and where to begin. Below is a list of ways to make your home a solar one.

Solar Attic Fans- Solar attic fans are a great example of a simple way to make your home more energy efficient without spending a lot of money. The need for air conditioning is reduced by venting hot air out of your attic. Installing a solar attic fan may also increase the life of your roof materials by keeping them at a lower temperature which also reduces moisture buildup in your attic. This prevents mold and rot in your home, and can also reduce allergens and pollution.

Solar Heating- Solar heating systems are composed of solar thermal collectors, a fluid system to move the heat to its point of usage, and a reservoir for heat storage. The systems may be used to heat domestic hot water, swimming pool water, or for space heating. If you live in the southern half of the United States or in an equally sunny area you could potentially save between 50% and 80% on your water heating by implementing a solar hot water heater. The initial cost is hefty, but depending on how you use it, the system may pay for itself in as little as five years. The return is greater when you factor in rebates and incentives offered by states and local governments.

Solar Pumps- Depending on where you live, especially in remote areas, the cost of traditional water piping may be exorbitant. Unless you install a solar water pump. A solar power panel collects solar energy and powers a battery which can keep a consistent and plentiful water supply.

Solar Paneling-The most obvious way to break in to the solar age is to install solar panel cells on your roof. Solar cells, also known as PV cells, or Photovoltaics, come in many sizes, colors, and performance characteristics, made to fit a variety of homes and lifestyles. Another important factor to consider is that when PV panels are used in conjunction with energy efficient appliances, not as many panels may be needed to power your home! Large scale home improvement stores, as well as smaller, independent energy groups, offer installation. But if you are a savvy do-it-yourselfer, you may decide to undertake the project on your own!

But don’t bust out the screwdriver just yet. Whether you do it yourself, or hire someone to do it for you, there are a couple of technicalities to be seen to before solarizing your home. Such as building permits. In order to legally install renewable energy sources in your home, you must contact your city or county building permit agency to obtain permission. You will be able to learn about requirements specific to your neighborhood. Don’t forget about property and sales taxes. Depending on what state you live in, you may or may not be exempt from these when it comes to the purchase of your renewable energy system.

Although it is not difficult to keep up your solar systems, frequency of replacement should be considered. Solar thermal systems need valves replaced every 3-5 years and storage tanks replaced every 10 years. Luckily, solar PV systems typically do not require maintenance, other than a yearly cleaning of the solar panels. PV panel life is typically 25 years.



Kim

Helen Rudd asked:


It costs you more money and uses more energy to heat and cool your home than any other system in your home. Typically, 44% to 50% of your utility bills pays for heating and cooling your home. Regardless of the type of home comfort systems you have in your house, you can save money and increase comfort by properly maintaining and upgrading your equipment.

Keep in mind that an energy efficient air conditioner alone will not have as great an impact on your energy bills as using an approach that involves the entire house. If you combine proper equipment maintenance and upgrades with appropriate insulation, weatherisation and thermostat settings, you can reduce your energy bills by up to 50%.

General Cooling Tips:

Use house fans. House fans help cool your home by circulating cool air throughout the house. They are most effective when the outside air temperature is cooler than the inside and when operated at night. An attic fan can blow away hot air that accumulates in the attic. This can go a long way to help the efficiency of your air conditioning system. Set your thermostat as high as comfortably possible. By maintaining a minimum difference between indoor and outdoor temperatures, you’ll lower your overall cooling bill. Don’t reduce your thermostat setting to a colder temperature than normal when you turn on your air conditioner. This will not cool your home any faster and could result in excessive cooling and unnecessary expense. Set the fan speed on high, except in humid weather. When it’s humid, set the fan speed on low. Consider ceiling fans to help spread the cooled air more effectively through your home without greatly increasing your power use. Keep lamps and TV sets away from your air conditioning thermostat. Shade air-conditioning units by planting trees or shrubs, but make sure you do not block the airflow. A unit operating in the shade uses up to 10% less electricity than one operating in the sun. Close shades or curtains on east, south, and west-facing windows during the hours when the sun’s intensity is at its peak. Open curtains and windows during early morning and overnight hours when the air outside the home is cooler. Turn off the air conditioner if the house (or air-conditioned rooms) will be unoccupied for an extended period. Use a programmable thermostat (link to product page) to turn Air off and on automatically when you know the house will be unoccupied.

Here are a few more steps you can take to substantially improve your home’s energy efficiency.

Take a Holistic Approach to Total Home Energy Conservation

To achieve the maximum in total home comfort and energy savings, we recommend that you step back and look at the big picture of energy consumption in your villa. The fact is, your total home comfort and efficiency is the product of many systems: heating, cooling, lighting & electrical, plumbing and possibly others working together. It is the interplay between these systems, combined with the size, age, physical features and location of your home, and even your lifestyle, that combine to produce the total energy efficiency of your home. Changing or upgrading one system, without considering the other factors will usually result in some improvement, but may not deliver the maximum possible benefit.

If you’re building a new villa, or considering a major remodel or system upgrade, consider an Integrated Systems approach. It may cost a little more now, but will undoubtedly save you a bundle over time. Skilled engineers and technicians will look at the big picture when designing a solution for your home.

Conduct a Home Energy Audit

The place to begin when evaluating your home’s overall energy efficiency and deciding how to reduce consumption and costs is with a Home Energy Audit. This takes into consideration much more than just your heating and cooling systems, and will give you a benchmark from which to make decisions and measure your energy saving progress.

Here are some of the heating & cooling factors your audit should take into consideration:

Insulation in walls, floors, and attic. Vapor Barriers in walls Quality of Windows — Single or double pane Heat loss around doors and windows Quality of insulation in doors Integrity of ductwork “— Any leaks Cleanliness of ductwork Use of “passive” solar energy Use of curtains and other window coverings to prevent heat loss Efficiency of heating and cooling systems — Condition of filters, etc.

Consider Purchasing an Annual Maintenance Agreement

You’ve heard the old adage, “If it ain’t broke, don’t fix it?” Well that doesn’t apply to your air conditioner any more than it does to your automobile. However, when your system is operating properly, it is easy to forget. Regular maintenance will save you the time money and headaches of premature system failures and major repairs. It will ensure that your system is always working at peak efficiency and help you avoid excessive energy costs.

Make sure your Air Conditioner is properly sized

Bigger Is Not Necessarily Better – A bigger room air-conditioning unit won’t necessarily make you feel more comfortable during the hot summer months and will most likely perform less efficiently and less effectively than a smaller, properly sized unit. Room units work better if they run for relatively long periods of time as opposed to being constantly switched on and off. The longer running time an air conditioner is allowed to maintain, the easier it is for the unit to hold a more constant room temperature. Running longer also allows air conditioning units to remove more moisture from the air, which reduces humidity and increases the comfort level in the room. Check specifications carefully when choosing the right air conditioner for your space. Central air-conditioning systems also require proper sizing. Professionals, however, should perform the sizing of your central air system. Also, do not use the system’s central fan to provide circulation. Instead, use circulating fans in individual rooms. Make sure you set the fan of your central air system to shut off at the same time of your cooling unit (compressor).

Use an Air Conditioner with a high Efficiency Rating

Select a room air conditioner that has an A rating or 10 or higher.



Annie

s.sankar asked:


1. INTRODUCTION: FUTURE ENERGY NEEDS

Mankind has recently enhanced its living standard and its population in an explosive way. In fact, the human population quadrupled and primary power consumption increased 16-fold during the 20th century [1]. The consumption of energy, food, and material resources is predicted to increase 2.5 fold in the coming 50 years. As a result of our efforts for better life, we have come to face, in this 21st century, serious global issues threatening our safe life or even our existence itself on our mother planet earth. These are issues such as global warming, environmental degradation, declining nutrition on land and sea from rising CO2, and rapid decrease of fossil reservoir. Since the living standard and the population of developing countries are increasing continuously, the demand of energy will be several times larger than that of today’s requirement by the time of the half way of this century.

In 2000, the world had 6.1 billion human inhabitants. This number could rise to more

than 9 billions in the next 50 years as shown in Fig.-1. This future population increase is mostly due to very rapid increase in less developed countries although the number in more developed countries will be almost constant (about 1 billion) or rather decrease [2].

Fig.-1 World Population Prospects [2]

The explosive increase in the human population inevitably requires an exponential increase in the consumption of energy, food, and material resources. One primary power source at present comes from fossil fuels such as oil, coal and natural gas. However, the fossil fuels have two serious factors which prevent them from being used for a long term as primary power source. One is their limited amount that does not last long if used with the same or higher pace than that of today (Fig.-2). The other is their negative feature of emitting carbon dioxide, one of the green house gases, which causes the global warming.

Fig.- 2 Pattern of Global Energy Dependence [3]

Fig.-3 Atmospheric carbon dioxide monthly mean mixing ratios. Data prior to May 1974 are from the Scripps Institution of Oceanography (SIO, blue), date since May 1974 are from the National Oceanic and Atmospheric Administration (NOAA, red). A long term trend curve is fitted to the monthly mean values [4]

Atmospheric CO2 has increased from 275 parts per million (ppm) before the industrial era begun to 379 ppm in March 2004 as shown in Fig.-3. Some scientists suggest that it will pass 550 ppm this century. Climate models and paleoclimate data indicate that 550 ppm, if sustained, could eventually produce global warming comparable in magnitude but opposite in sign to the global cooling of the last Ice Age [5].

Global energy demand continues to grow along with worldwide concerns over fossil fuel pollution, the safety of nuclear power and waste, and the impact of carbon-burning fuels on global warming. As a result sustainable energy sources like solar, wind, hydropower, biomass, geothermal, hydrogen, ocean thermal, tidal power etc are drawing prime attention, out of which solar power is the most promising one. Terrestrial solar power has too many limitations like atmospheric attenuation, daily and seasonal variation, and affects by climate conditions etc. To overcome these limitations concept of Solar Power from Space is getting momentum, which was first proposed by Czech-American engineer Peter Glaser as a solution to the oil crises of the 1970s [6]. Solar Power from Space is a proposed concept to place a gigantic solar power station in space orbiting around the earth that uses microwave power transmission to beam solar power to a very large antenna on earth where it can be used in place of conventional power sources.

2. SPACE SOLAR POWER (SSP) vs TERRESTRIAL SOLAR POWER (TSP)                   

The SSP concept arose because space has several major advantages over earth for the collection of solar power. Space is free from day-night cycle, atmosphere, clouds, dust, rain, fog and other climatic changes, so it would receive 30% more intense and at least eight times more sunlight than that of at ground constantly and continuously unaffected by the weather. In geosynchronous orbit it would receive sunlight almost 24 hours a day hence avoiding the expensive storage facilities necessary for earth-based solar power systems.  Since earth’s axis is tilted, it would be in earth’s shadow only for 70 minutes maximum at late night when power demands are at their lowest, during 42 days near the equinoxes [7] as shown in Fig.-5.

Fig.-5 Daily duration of eclipses as a function of the date [7]

3. SSP: SYSTEM DESIGN AND TECHNOLOGIES

The SSP system is composed of a space segment and a ground power receiving site (Fig.-6). Space segment consists of mainly three parts; solar energy collector to convert the solar energy into DC (Direct Current) electricity, DC-to-microwave converter, and large antenna array to beam down the microwave power to the ground. Ground power receiving site uses a device called rectenna (rectifying antenna) to receive and rectify the microwave power beam. The rectenna system converts the microwave power back to DC power which is then converted to conventional AC (Alternating Current), and is connected to existing electric power networks.

Assuming typical values for efficiencies like 15% for solar panels to convert solar energy into DC, 70% conversion rate in the space segment from DC to microwave, 90% beam (power) collection efficiency, and 80% conversion rate for rectenna from microwave to DC in ground segment, the estimated over-all efficiency is approximately 7.5 %. With such efficiency a SSP space segment would be of size of about 50 km2 (5 km x 10 km) to generate 5 GW DC power on earth (Fig.-6).

Fig.-6 : Reference Model: 5 GW GEO based Space Solar Power Station Designed by US Department of Energy (DOE) and NASA in 1979 [8]

3.1 -SOLAR CELL: EFFICIENT STRUCTURES

In the very near future, breakthroughs in nanotechnologies promise significant increase in solar cell efficiencies from current 15% values to over 50% levels. That might decrease required size of space segment by about 3 fold. Author proposes Metal-Metal junction cavity solar cell which theoretically promises to increase solar-electric conversion efficiency many folds.

A cavity of metal m2 (work function W2) with thin polish of metal m1 (work function W1, W1

·  The major loss in usual structures is the reflection loss (about 30%) but in M-M cavity solar cell once ray enters in cavity, undergoes multiple inner reflecti



Christopher