[TEMPLATE]Renewable Energy[/TEMPLATE]
[TEMPLATE]Equipment & Tools[/TEMPLATE]
[TEMPLATE]home improvement store[/TEMPLATE]
Home Solar Power Systems: How Many Kilowatts (kws) are Created?
Author: Daniel Stouffer
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.
Article Source: http://www.articlesbase.com/education-articles/home-solar-power-systems-how-many-kilowatts-kws-are-created-449597.html
About the Author
At Solargies (Solar Energies), our objective is to spread the adoption of renewable solar energy as rapidly as possible. Daniel Stouffer is writer and promoter of green energy. Learn about Renting your own Solar Energy system at: => http://www.solargies.com/Residential_Solar_Energy.htm
[TEMPLATE]amazon search[/TEMPLATE]
Whats the annual energy output of the average solar panel.?
What is the average annual energy output of solar panels that can be installed on the home?
I am considering a solar panels. How can I tell if my area gets enough solar energy a year to be worthwhile?
I want to know how I can determine my area’s (Rochester NY) yearly solar energy output to see if it would make economic sense to install solar panels. Any websites or resources where I can look?
In terms of solar energy output, what does TSI stand for & is it highest during low or high sunspot activity?
Oddly enough, I’ve read what appear to be contradictory claims in articles about plotting TSI against sunspot cycles. Please explain.
Solar energy output in watts?
If I have 491 square meters of solar cells, what kind of output (in watt hours) could I expect?
They’re developing 80% efficient solar cells, and I’m planning for the future, so what kind of energy would I get with those, assuming it were a sunny day?
How many solar panels would you need to equal the energy output of 1kg of U-235?
How many solar panels would you need to equal the energy output of 1kg of U-235?
if 1kg of U-235 can produce 80 trillion joules (8×10^13 J) of energy how many solar panels would you need to equal this amount of energy?
Any info would be very much appreciated!
Generally you can assume that average irradiance of the sun at the Earth’s surface is 1000 watts per square meter. Multiply that by the square meters of panels you have and factor in the efficiency of the panels. Today, the most efficient photovoltaic panels that are readily available have effiencies less than 20%.
TSI is Total Solar Irradiance i.e. the light from the Sun
The measure is Watts per square meter (W/m2) this graphs shows the difference over the last three solar cycles
http://en.wikipedia.org/wiki/File:Solar-cycle-data.png
The average is ~1366.5W/m2 at the peak of the cycle to ~1365.5W/m2 at the low of the cycle, a difference of less than 0.1%
The energy output is highly dependent on the location. For a specific area, you can look up the equivalent peak sun hours per day here:
http://rredc.nrel.gov/solar/old_data/nsrdb/redbook/atlas/
Let’s say that it says the peak sun is 5 hours / day in your location. Then a typical 200-watt panel would have 5 x 200 = 1000 wH = 1.0 kWh per day, or 365 kWh annually. The tables above already take into account average cloudy days, and seasons.
A typical size installation would have perhaps 16 of these panels, but it could be less, or much more.
Unless the student is supposed to be able to calculate how long it takes the U-235 to produce that amount of energy, there is not enough information. If that is within the scope of the course, the question is way out of my league.
But assuming you just left out the time when stating the problem, divide that into 80 trillion to get joules/sec.
Let’s say the time is 40 billion seconds* for the U-235 to generate 80 trillion J. Divide 80 trillion by 40 billion, that’s 2,000 J/sec. You would need 10 panels. (A typical panel produces 200 Joules/sec.)
*That’s a LOT of seconds, even a lot of centuries. By then the solar panels would have worn out and crumbled into dust, so it’s a silly question in that sense. Is the teacher trying to make a point about the futility of solar power?
If you are looking for the cheapest electrical power available solar panels are not going to be what you want.
Roughly solar panels will supply electrical power costing about 3-10 times more than what you can purchase from your local electrical company when averaged over the 20-25 year life of any solar panels.
Go look at how much you spend for your electricity in a single year. Then go look at how many solar panels you can purchase for this amount of cash (In my case I spend about $1000 each year for power).
This means that economic “sense” must be tempered with some other desire for the solar panels.
I came accross a new, proven and tested home made wind power system and solar power system which eliminates our electricity bills. It was written by a Renewable energy enthusiasts Michael Harvey the diy called Earth4energy. You can get your copy to save energy and help environment while eliminating your power bills. Get it from here:
http://how-to-build-cheap-solar-energy.blogspot.com/