Daniel Stouffer asked:


The first thing you might ask - what is solar radiation and how does it related to solar generated electricity? That is a good question and a topic discussed in our next article in our series dedicated to home solar power. This article, on the other hand, explains how kilowatts are calculated based upon the energy output of your solar array. We will also highlight the difference between solar cells connected in parallel versus in series. The average American home uses about 25 kWh of electricity per day. The following example illustrates how to calculate the power produced by a residential solar energy system. Looking over a solar radiation grid, we can determine that a residence gets five daylight hours of solar radiation in one day which is then averaged out over the entire year. Solar radiation maps are highlighted on may websites throughout the Internet. You can do a quick search for "solar radiation" to find one. In any area across the entire United States, they detail out the amount of sunshine hitting a given location based upon the time of year and its address. Calculating the power from a solar energy system Divide the average kWh per day by the average sun hours per day. For this example, we take 25 kWh divided by 5 hours of sun per day = 5 kW system This 5 kW system will generate 25 kWhs under optimal conditions in direct sunlight for 5 hours, or 25 kWh on an average day with some at peak production and most of the sunlight at less than optimal angles. Future articles related to solar energy will continue to explain the effects of sun angle, reflection, and refraction on the design, output, and installation of solar panels. Energy as it Pertains to Solar Modules Individual solar modules that are measured in watts have a particular voltage (around 40 volts) and a particular amperage (around 5 amps). A solar module with 40 volts and 5 amps is called a 200-watt module, which means that it has the potential to produce 200 watts of electricity when in direct sunlight, away from trees or shading, and clear of snow or debris. Since most electrical components around your house are only rated for 600 volts DC, it is rare to see a solar array with a string larger the 15 solar modules. On the other hand, since inverters need a minimum voltage or pressure to turn them on, you will seldom have a solar array with a string solar modules with a size smaller then 6. Electrical components, like solar cells, panel modules or batteries, can be connected in either series or parallel. This makes a big difference in the total quantities of energy produced from the solar energy system, as well as the stability of the technology over time. Each solar module or component has a positive and a negative pole. In essence, this is the same way batteries have their negative and positive poles arranged. Take a look at how you but batteries in a flashlight. Same idea here. The manner in which these poles are connected makes a big difference. Connect Solar Panels in Series When you connect residential solar energy systems in series, you connect the positive (+) pole on one component to the negative (-) pole on the next. When modules are connected in series, the voltages are added. Adding voltage together in this fashion creates a long chain of solar modules all working together, depending upon each other, and creating a flow of current that increases along the length of the system. These modules in series are called Strings. The average string is 8-12 modules so the voltage would be 320 - 480. Unfortunately, we encounter some negative aspects of of this type of construction. Connecting Solar Panels in Parallel When you connect solar panels or components in parallel, you connect the panels so current can travel to your inverter and to your house via multiple paths. Unlike adding solar modules in series which increases the volume of current as it goes, the solar panels connected in parallel has the effective of leaving the current or volume of electricity passing through the system the same. Solar panels or strings of solar arrays tied together in parallel are called parallel systems. Their amps are combined together but the total voltage remains the same. Adding amps is like increasing the volume, the pressure stays the same but the volume goes up. Inverters can only handle so much volume so you will seldom see more than 1 to 3 strings in parallel; positive ends to positive ends with negative ends to negative ends. One of the advantages of parallel connection is that electricity continues to flow, even though one of the components (or strings) is damaged. If a system is entirely in series, one damaged component stops the entire system. You may remember the ever-frustrating Christmas lights that were connected in series. Often difficult to trouble shoot, strings of lights connected in series are hard to fix when one bulb blew out. Now, the modern Christmas lights are connected in parallel. You are able to determine this easily. There are usually two different wires coming in and out of each bulb. You can feel this via their less frustrating maintenance and operation. Options for Residential Solar Energy Systems In this article, we explained in some detail how solar modules calculate the power they produce as well as how connecting solar arrays in series or parallel can have an large impact on energy output as well as complexity of design. Our next article will cover how sun angle affects solar energy systems and how to quantify the solar power produced from the sun. New solar energy system rentals allow you to upgrade your home to solar generated electricity with no large system to purchase. You can rent the solar energy equipment needed to generate up to 100 percent of your electricity needs. Exciting aspects related to clean, green solar energy are emerging all around us.

Bio Fuel Video Channel

Paul Calhoun asked:


Introduction: Global warming impact to our quality and cost of living is large and very catastrophic. Homeowners are well aware of the increasing energy costs to heat, cool and illuminate their homes. The increasing costs of oil and other fossil fuels are daily headlines. The insatiable demand for energy to fuel world growth guarantees that the cost of these limited fuels will continue to increase. Political/economic forces will determine the rate of increase for fossil fuels. In addition, the increasing cost of global warming using fossil fuels is slowly being recognized. The world is slowly beginning to understand the urgent need for renewable energy sources. However, each of these alternative energy sources brings major advantages and disadvantages. An example is wind generated energy. Wind energy is available to the whole world and generates electricity competitively with fossil fuels. The technology is understood and easy to apply. But, there are big objections to a windmill in "my back yard". Also, the number of birds and bats that will be crushed with wind power generation is not a warming thought. Wind technology will be a component of our energy solution. However, because of the above concerns, we need other major solutions to meet our demand for energy sources. This search leads us to solar energy. The amount of sun energy striking our world in one day is sufficient to supply our energy demands for a year. We will not run out of this source in the foreseeable future. The major barrier to harnessing solar energy has been cost and convenience. For example, drying clothes in a dryer is easier than hanging clothes on an outside line, thus convenience precluded efforts to find more energy efficiency. We can convert solar energy to electricity but with a major capital cost. Greater acceptance and use of solar energy will lead to lower cost. Solar Energy: Energy from solar energy can be divided into two major categories: Passive Solar Energy: This technology ranges from clothes drying in the sun to solar heating for hot water and many other passive techniques. All are important for our present and future quality of life. The technology is well understood and can be implemented as economics and space conditions allow. Active Solar Energy: One of the active solar energy technologies is converting solar energy directly into electricity. It is called photovoltaic cell or PV. This is a device that converts light into electricity using the photoelectric effect. The first working solar cells were constructed by Charles Fritts in 1883. These prototype cells were made of selenium and achieved efficiencies around one percent. The silicon solar cell was created in 1954. The solar cell has benefited from the development of silicon semiconductors. Physics of Active Solar Energy: The physics of photon to electricity conversion is well understood by physicists. The basic model is of a photon from the sun which strikes the cell material and excites electrons that emit electricity. This model is simple compared to the complexity of modern day semiconductors. The major variables of PV electrical generation are cell material and impurities in the cell material. Manufacturing Technology for Active Solar Energy: Primarily single crystal, high purity silicon has been used to generate photon to electricity conversion. The manufacturing techniques for single crystal silicon and limited quantities of pure silicon impose a high cost for PV devices. Shortages of refined silicon have been hampering production worldwide since late 2004. This shortage persists to this date and has slowed PV growth. New materials are starting to come forward which should lower the PV materials hurdle. Efficiency growth of Active Solar Energy: Since the silicon PV invention in 1954, cheaper fossil fuel prices largely removed solar power from the public consciousness. Annual growth of electrical generation by PV ranged from 10 to 20% percent throughout the 1980's and 1990's. Worldwide installation of PV reached 1000 megawatts in 1999. Manufacturing costs for PV arrays has been dropping 3 to 5% over the recent years. This cost drop began to expand the use of PV electricity generation. Total peak power of installed PV was around 6000 megawatts at the end of 2006. Installed PV is projected to increase to over 9,000 megawatts in 2007. The average lowest retail cost of large photovoltaic arrays has declined from $7.50 to $4.00 per watt between 1990 and 2005. PV materials have also been improving in recent years. The most recent materials approach is to process discrete cells on silicon wafers cut from multi crystalline ribbons which form thin films. This approach is the least expensive of known technologies. This group of technologies includes amorphous silicon cells deposited on stainless-steel ribbon, cadmium telluride (CdTe) cells deposited on glass, and copper indium gallium dielenide (CIGS) alloy cells deposited on either glass or stainless steel substrates. The efficiencies of these new materials are currently at 20%. Many researchers are working to improve the efficiencies. An added advantage of the new thin films is that they are flexible and are currently being used in roofing materials. Current Trends in Generating Active Solar Energy: Commercial businesses like Google, IBM, BJ's Wholesale, Estee Lauder, Kohls, Target, Tiffany & Co., Wal-Mart are installing PV solar energy. From "big box" discount giants to high end commercial businesses PV solar energy is finding acceptance in 2007. The most recent retail-outfitter to become part of this trend is Macy's, which announced earlier this month that it will install solar powered systems on 26 stores throughout California. These leading companies are turning to solar power because it makes good business sense and supports their environmental initiative. Creative financial arrangements allow these companies to afford the upfront capital costs and payback their loans with energy savings. So what does all this mean to the average home owner? PV Cost per Kilowatt (kWh): In the California market, where state incentives and net metering are in place, PV electricity prices are dipping below 11¢/kWh, on par with some utility-delivered power. Moreover, according to the U.S. PV Industry Roadmap, solar electricity will continue this trend and become competitive by 2010 for most domestic markets. The outlook is very positive for PV generation of electricity. Once the capital investment is made, the cost of PV electricity is equivalent to fossil fuels and will continue to decrease. Cost of PV Installation: The cost of installation is the major barrier that has to be overcome for widespread PV acceptance. Around 59% of world solar product sales installed in the last five years were applications that are tied to the electricity grid. Solar energy prices in these applications are 5-20 times more expensive than the cheapest source of conventional electricity generation. This premium is well beyond the reach of the average home owner. Fortunately, there are financial models coming forward to enable the consumer to finance PV solar installation and pay for this installation with the electrical savings. In order to make these financial models successful, federal and state incentives are needed and the installation should be connected to the electrical grid. These connections allow the home owner to sell back electricity when excessive amounts are available and to receive electricity when solar conditions do not allow sufficient electricity. Only fifty percent of our states have modernized to allow on-grid PV solar energy. Berkeley, California is leading the way to enable it citizens to save electrical cost and meet environmental needs. Here is how their plan works. A property owner hires a city-approved solar installer, who determines the best solar system for the property, depending on energy use. Most residential solar panel systems in the city cost from $15,000 to $20,000. The city will pay the contractor for the system and its installation, minus any applicable state and federal rebates, and would add an assessment to the property owner's tax bill to pay for the system. The extra tax would include administrative fees and interest, which would be lower than what the property owner could obtain on their own, because the city would secure low-interest bonds and loans. The tax would stay with the property even if the owner sold, although the owner would have to leave the solar panels. The property owner would save money on monthly Pacific Gas & Electric bills because electricity generated by the solar panels would partly replace electricity delivered by the utility. After the assessment expired, the solar panels, of a simple technology that requires little or no maintenance, would continue to partly replace PG&E electricity. The Berkeley plan is a map for the rest of the world to allow us affordable electricity and meet our responsibilities to the environment. I have a BS and MS in Metallurgical Engineering. Thirty six years spent in the development of semiconductors. Business experience in start up business plan. Currently, an oyster farmer and interested in helping the environment by deploying solar energy. Please visit my Web Site http://www.charlestonenvironmentalhelp.com AddThis Social Bookmark Button

Electric Cars Video Channel

Anna Hart asked:


Solar energy is a potential source of free electricity and water heating. It offers the power to enjoy electrical power in remote areas of the world. It seems to offer health and safety along with power, but does it? Solar energy health risks are seldom mentioned. That may be partially due to the limited use of this source of energy. It may also be due to the lack of research in this area. Some have begun to study solar energy health risks, however, and if one researches long enough, a few estimates are available. Thermal Solar Energy Health Risks Solar energy health risks are inherent to the design and installation of most thermal energy systems. These are the systems designed to heat water and air for household use. Solar water heaters complete three basic operations before delivering hot water to your faucet or your heating unit: 1. collect sunlight and convert it into heat energy. 2. circulate fluids that transfer the heat energy to a storage unit 3. store the hot water until you need it The solar energy health risks with such a system usually occur in the storage units. Some units allow for the growth of allergenic molds and fungi. If proper materials are used for the storage unit, however, these solar energy systems present few, if any, health risks. Their advantages are that they are far safer than most fossil fuels or nuclear power - they have no emissions and do not pollute the air. PV Panel Solar Energy Health Risks The solar energy health risks associated with photovoltaic (PV) panels occurs before the panels are put into use on the consumer's home. PV panels are the panels used to collect solar energy from sunlight and convert it into usable electricity. The manufacture of PV panels requires the use of toxic materials. Silicon dioxide is mined from sand or quartzite and reduced with heat to pure silicon. Materials released during refining are the main health risks. Several steps in forming the photovoltaic cells utilize toxic materials. These are sprayed on the cells, and can readily be inhaled. It is estimated that solar energy health risks associated with producing PV panels per unit energy may be between 11 and 21 deaths per quadrillion joules of energy produced. Solar energy health risks from PV panels are very slight once the panels are produced and installed on the consumer's home. This type of solar energy is known for reliability and low maintenance. The home owner seldom needs to be involved in any repairs, and thereby cuts solar energy health risks. Passive Solar Energy Health Risks Passive solar energy provides safety and health. A new building that maximizes this technology can reduce energy costs by nearly one half. How? 1. Warming indoor air in a house through vertical, slanted windows facing the sun. The windows capture maximum solar energy from the sunlight. 2. Collecting solar energy in adobe or stone walls and floors, and then releasing it into the air as the temperature falls. 3. Collecting solar energy in a sun space, much like a greenhouse built on the sunny side of the home. This heat is sent into the home with proper ventilation. 4. Holding water in black roof tanks until needed, cutting the working time of the home's hot water heater. 5. Using clerestories - rows of windows near roof peaks that catch sunlight and bounce it through the building. The sunlight reduces the need for electric lights. In Summary Solar energy technologies present few, if any, health risks for the end user. Their use can reduce the health risks presented by other energy sources, providing cleaner, safer, more cost effective energy.

Hybrid Cars Video Channel

Bryan Wong asked:


When the electrical utility bill is increasing each and every month you can do a few things. You can cry and pull out your hair; refuse to pay and get cut off and have no utilities; you could work harder and more hours each month to keep up the rising costs; or you could invest in other alternative sources of energy to cut the electrical utility bill. One of these alternative sources of energy is solar energy. And indeed, you will need to invest that means putting in your own (or borrowed) money, but the investment can make a huge difference for now and many years to come. Solar energy is derived from the power emitted by the sun to produce energy. The sun emits enough energy on the Earth in one day to supply the needs of the world for one year. The amount of solar power that the Earth receives from the sun is estimated to be 770 trillion kilowatts or an amount 5,000 times bigger than the sum of all energy resources we are using, may it be nuclear, geothermal, or gravitational energy. The estimated remaining life of the sun is around 4.5 billion years. Solar power is produced primarily through the use of photovoltaic cells, or commonly known as the solar cells. The process of converting solar power into electricity is as follows: The solar cells are placed under direct sunlight. The rays of the sun hits the cells initiating a chemical reaction that creates an electric current. This current is later turned into electricity. There are two classification of solar power: passive solar and active solar. The first classification does not make use of panel systems or other moving mechanisms to produce solar power. Instead, it involves planning a structure in such a way that it can capture the rays of the sun with windows, tanks, and other permanent structure. This system can be used to provide heat to houses, water, and so on. The second classification involves the solar panels or the group of solar cells. These panels are placed in such away that its exposure to the sunlight is maximized. It will convert sunlight to electricity, which is transformed later on from direct current (DC) electricity to alternate current (AC) electricity, and consumed it immediately or store it in batteries. It may be also fed into the grid system of the local utility. The Pros and Cons of Solar Power There are some disadvantages of using solar power. These are the following: Initial costs on installation of solar power systems can be quite expensive. Cloudy weather condition can be a problem in collecting solar power for some systems. If you live in area where there is little sun shine this will be a problem. Solar power can not be produced at night. There are numerous advantages of using solar power. These are enumerated in the following items: Solar power is almost limitless. Remember that the remaining life span of the sun is estimated to be 4.5 billion years. It is relatively abundant. It can be absorbed, reflected, transmitted, and insulated. It can be stored in batteries for night time use. Using solar power is not only a solid investment for years to come it also saves the environment. Thus this investment is not doesn't only saves you money but you making this world a better place to live in for years to come. Investing in solar power is worth your money, don't overlook the potential.

Electric Cars Video Channel

Bryan Wong asked:


In the early days of solar power there were huge installations necessary to make use of this energy source. The solar panels that were needed were larger than the average full grown man. This made the collection of solar power a bit of a challenge. Therefore making use of solar power was not suitable of everyone. It was expensive and a bit of a chore as well. These huge solar panels still exist in solar power plants, which produce energy for certain parts of the world. But over the years technological advancements have made solar power affordable and portable enough so common people can use it for their everyday lives. Nowadays solar panels have become so small that pocket calculators use these as an alternative power source to the usual single cell batteries. But the use of portable solar power did not stop with the use of pocket calculators. Numerous inventions have made use of portable solar power and some of these are available all over the world. Let's take of look at 5 affordable uses of portable solar power. 1) BRUNTON BATTJACK Batteries and Chargers The charger comes with the SolarPort 4.4, wall transformer and 12V car cord to charge batteries from AC or in a vehicle. The charger can hold 4 AA or AAA rechargeable batteries. The kit has 4 1500 mAh NiMH AA battery cells. The charger will switch to trickle charge when the batteries are fully charged. It also has a discharge option for maintaining NiCad batteries. This will cost $30. Batteries are NiMH AA dry cells, have a 1500 mAh capacity, can recharge for hundreds of times, and come in a package of 4 AA batteries. These cost $14. 2) SS-PVSMALL Power System This portable solar power system from Silicon Solar Inc is easy to use and needs no assembly. Included in each system is an inverter/battery carrying case and 8.5 or 17-watt solar panel/charge. This system can power a laptop computer, portable audio devices, small coloured TV, and most devices that need less than 140 watts AC 110-120v, and 60Hz input. Power time can range from 30 minutes to 56 hours, depending on the equipment being powered up. The system is also used for indoor/outdoor lighting, and is lightweight. The system also includes inverters, cables, battery box, and sealed gel cell battery. The system comes with a 1-year warranty. The system costs $149.95. 3) UNI-KIT The Uni-Kit system is a portable, durable, solar powered lighting system that can provide extended lighting hours to its users. This is powerful enough to let even a 12-volt radio or TV operate, and easy to install. The Uni-Kit system also comes with a basic power controller that maximizes battery life of its 12-Volt Deep Cycle SLA Battery by controlling its charging and load use, and protects the system from overcharging and excessive discharging. Uni-Kit can be used in the garage, tool sheds, remote homes, isolated buildings, surveying sites, construction sites, camp sites, and even during water pumping operations. Uni-Kit comes with an 11-watt fluorescent lamp that has a 1-year warranty. The 15-watt solar panel has a 20 year warranty. You can add up to 4 lamps to increase the system's illumination capacity. The default kit weighs 10 pounds and can be purchased for $249.95 from Silicon Solar Inc. If you have additional 4 lamps, all 4 will cost an extra $235. 4) BRUNTON Portable Solar Panels Brunton has portable CIGS (copper indium gallium diselenide) solar array panels that are thin and lightweight to save weight for backpackers. These panels produce standard 12volts outputs, and come with basic 12V vehicle socket, 4 different jack plugs, and battery clips. Solar array panels come in a 6 and 12 foldable, and 14 roll able series. Prices of these panels range from $129 to $399. 5) EN-R-PAK AC/DC Backup Power Supply The EN-R-PAK backup power supply 200 series are compact solar power backup supplies that have built-in electronics that store, control, and produce energy from the sun, wind, or flowing water. The system can accept additional solar panels, wind turbines, or water turbines. These power supply systems use renewable stored energy to produce 115 volts and 12 volts DC. A 230-volt unit is also available for international use. The EN-R-PAK can provide emergency power for a home or office, remote areas, a cabin or cottage, for communications, wherever and whenever you need power! This system has no parts that wear out, is environment friendly, quiet, does not emit harmful fumes, easy to operate, requires no assembly, needs almost no maintenance, and is designed to survive rugged weather conditions. These can also power energy efficient lights, a laptop computer, a small TV, rechargeable power tools, and other electrical equipment. The EN-R-PAK has a 1-year system warranty, 20-year solar panel warranty, 2-year battery warranty, and is built to conform to UL, NEC, and CSA electrical standards. EN-R-PAK 50-watt solar panels are liquid-proof and shatter proof. These also come with a blocking diode, 30 feet of cable with a connection plug. Wind turbines are also configured to the EN-R-PAK so changes to the power centre are not needed. The basic system will cost $1500. Additions to the system will make the cost reach a maximum of $2950. This sums up the possibilities for portable solar power. As time and knowledge progress other devices and possibilities will be available on the market. The prices mentioned here can give you an idea, but are by no means accurate.

Wave Power Video Channel