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solar panels

Read and learn more about solar panels. For more, visit the Renewable Energy website EnergySourceRenewable.org

Q: Solar Panels?
I am purchasing a home that includes 2 solar panels measuring 8 foot by 4 foot located on the roof. Neither myself or the home inspector located a box that the solar energy would transfered to. should there be a box? also what can i expect from the solar panels? Thanks for the help…

A: Go up to the attic and see if there are wires or pipes coming from the panels. Could be you have a solar water heater. They are more common. Your hot water system will have a circulating pump controlled by a thermostat.

Electric solar panels will generate DC which will not be usable in a standard house unless it is converted. Solars usually are used in conjunction with batteries.

Q: solar panels?
im looking to get solar panels. what type should i get? who is the best company to buy from? do i need to have someone come to my house and evaluate it? and if it make any difference i live in southern california in tulare county

A: This may help. I dont want to tell you where to go so I have provided you with enough info to make the decision on your own.
Types of technologies
Many technologies have been developed to make use of solar radiation. Some of these technologies make direct use of the solar energy (e.g. to provide light, heat, etc.), while others produce electricity.

Solar design in architecture
Main article: Passive solar building design
Solar design in architecture involves the use of appropriate solar technologies to maintain a building’s environment at a comfortable temperature through the sun’s daily and annual cycles. It may do this by storing solar energy as heat in the walls of a building, which then acts to heat the building at night. Another approach is to keep the interior cool during a hot day by designing in natural convection through the building’s interior.

Solar heating systems
Main articles: Solar hot water and Solar combisystem
Solar hot water systems use sunlight to heat water. They may be used to heat domestic hot water, for space heating or to heat swimming pools. These systems are composed of solar thermal collectors, a storage tank and a circulation loop.[8] The three basic classifications of solar water heaters are:

Batch systems which consist of a tank that is directly heated by sunlight. These are the oldest and simplest solar water heater designs, however; the exposed tank can be vulnerable to cooldown.[9]
Active systems which use pumps to circulate water or a heat transfer fluid.
Passive systems which circulate water or a heat transfer fluid by natural circulation. These are also called thermosiphon systems.

A Trombe wall is a passive solar heating and ventilation system consisting of an air channel sandwiched between a window and a sun-facing wall. Sunlight heats the air space during the day causing natural circulation through vents at the top and bottom of the wall and storing heat in the thermal mass. During the evening the Trombe wall radiates stored heat.[10]

A transpired collector is an active solar heating and ventilation system consisting of a perforated sun-facing wall which acts as a solar thermal collector. The collector pre-heats air as it is drawn into the building’s ventilation system through the perforations. These systems are inexpensive and commercial models have achieved efficiencies above 70%. Most systems pay for themselves within 4-8 years.[11]

Solar lighting
Main articles: Daylighting and Light tube
Solar lighting or daylighting is the use of natural light to provide illumination. Daylighting directly offsets energy use in electric lighting systems and indirectly offsets energy use through a reduction in cooling load.[14] Although difficult to quantify, the use of natural light also offers physiological and psychological benefits.

Daylighting features include building orientation, window orientation, exterior shading, sawtooth roofs, clerestory windows, light shelves, skylights and light tubes.[15] These features may be incorporated in existing structures but are most effective when integrated in a solar design package which accounts for factors such as glare, heat gain, heat loss and time-of-use. Architectural trends increasingly recognize daylighting as a cornerstone of sustainable design.

Daylight saving time (DST) can be seen as a method of utilising solar energy by matching available sunlight to the hours of the day in which it is most useful. DST energy savings have been estimated to reduce total electricity use in California by 0.5% (3400 MWh) and peak electricity use by 3% (1000 MW).[16] However, there is some question whether these estimates are valid. In 2000 when parts of Australia began DST in late winter, overall electricity consumption did not decrease, but the peak load increased.[17]

Solar pond
A solar pond is simply a pool of water which collects and stores solar energy. It contains layers of salt solutions with increasing concentration (and therefore density) to a certain depth, below which the solution has a uniform high salt concentration. It is a relatively low-tech, low-cost approach to harvesting solar energy. The principle is to fill a pond with 3 layers of water:

A top layer with a low salt content.
An intermediate insulating layer with a salt gradient, which sets up a density gradient that prevents heat exchange by natural convection in the water.
A bottom layer with a high salt content which reaches a temperature approaching 90 degrees Celsius.
The layers have different densities due to their different salt content, and this prevents the development of convection currents which would otherwise transfer the heat to the surface and then to the air above. The heat trapped in the salty bottom layer can be used for heating of buildings, industrial processes, generating electricity or other purposes. One such system is in use at Bhuj, Gujarat, India[26] and another at the University of Texas El Paso.[27]

Solar chemical
Solar chemical is any process that harnesses solar energy by absorbing sunlight in a chemical reaction in a way similar to photosynthesis in plants but without using living organisms. No large-scale systems have as yet been constructed.

Another chemical (but not photochemical) approach has been to use conventional solar thermal collectors to drive chemical dissociation reactions. Ammonia can be separated into nitrogen and hydrogen at high temperature and with the aid of a catalyst, stored indefinitely, then recombined later to release the heat stored. A prototype system was constructed at the Australian National University[28].

A promising approach is to use focused sunlight to provide the energy needed to split water into its constituent hydrogen and oxygen in the presence of a metallic catalyst such as zinc.[29]

While metals, such as zinc, have been shown to drive photoelectrolysis of water, more research has focused on semiconductors. Further research has examined transition metal compounds, in particular titanium, niobium and tantalum oxides.[30]

Unfortunately, these materials exhibit very low efficiencies, because they require ultraviolet light to drive the photoelectrolysis of water. Current materials also require an electrical voltage bias for the hydrogen and oxygen gas to evolve from the surface, another disadvantage. Current research is focusing on the development of materials capable of the same water splitting reaction using lower energy visible light.

It is also possible to use solar energy to drive industrial chemical processes without a requirement for fossil fuel.

Q: Solar panels?
Following the anvil on a cable in space question. why not attach a couple of wires to a load of solar panels floating in orbit? solving all our energy problem needs. or cover the sahara with solar panels. aparts from a few scorpions and nomads who’s it gonna hurt?

A: 1. Solar panels are extremely inefficient, on the order of only 1-2% efficient.

2. The cost is so high, it is not worth it. The panels cost far more than any “free” electricity.

3. The cable from space would be too heavy, and air resistance would bring the solar panels down.

Instead, use mirrors to concentrate the sunlight, and use it to drive a steam turbine. The efficiency can easily be over 90% if done properly, yielding about 1,000 watts per square meter at high noon at the equator. A mere 20 square kilometers would provide about 360 megawatts. and 2/3 of the energy can be stored for evenings and cloudy days.

Q: SOLAR Panels?
Hello from SO TX.. I would like to know if anyone out there has SOLAR PANELS on their home?
I have a 850 sq ft. house. I called Austin to a company that offers panels and installation. The cost $18,000.00, for 10 panels . The rep said we would save about 21 to 25% on our electric bill /mo. We use approximately 980 kw/mo. Our bill is around $140.00 / mo…I really don’t think that’s a good enough savings. We figure it would take 25 years to recoup our investment.
And where we live in TX it does not offer any incentives. The gov. allows you a $2000.00 tx break.

A: You are wasteful in your power usage. To use 980 kWh per month in such a small home is just unbelivable. Chage your lights to CFL (a 28 watt cfl is = to a 100 watt bulb) and use space heating and window A/C units. Unplug that tv set when not in use and same for other items. I found that our tv set alone uses amost 12 watts when turned off. You may say that is not much.. Well add in 4 tv sets and a couple of stereos and other items and do it for a years time. lots of waste. Our home is twice the size of yours and we only use on a heavy month about 500 kWh. With 1860 watts in solar power my last months electric bill was 19 dollars and most of that was meter fees.

18K is really about right and not bad. You will get back 2000 dollars if installed before the end of 2008 but it looks like we may be Bushed and they may not extend the tax credits.
Just have to wait for John McCain to get in office and hope he will do something about it. But McCain is running for a 3rd bush term. Hillary is not going to make it in to office an every time Obama gets under pressure he gets so scared he starts stuttering. So he will just get walked on by big oil and big money. So better do it now while you can get something back.

Just to clear something up about the cost.. If you rent power you have nothing in 30 years but if you buy a system you have a system in 30 years.

As far as new lower priced solar modules.. BS!!! Big time
BS!!!

If they can make a 3000 watt solar module for 1 cent they can sell it for the current market price. So it would take a FOOL to drop the prices. So don’t waste your time setting on your thumb waiting for this great lower price.

Ask Evergreen Solar if they lowered prices when the used OUR TAX DOLLARS to find a new way to make their panels. Well they found a cheaper way and did it and charge the same as anyone else. But that don’t stop them from braging. If they can get your money and don’t take it they woudl be fools.. Would you drop your price if people would pay the higher price? Plus someone would by them out and bring the prices back up anyway..

Q: How does Solar Panels works and what is the cost of getting a solar panel installed.?
I have heard a lot about solar panels and I want to know how these solar panels works and is it really possible to generate electricity using solar panels. And what is the cost of getting a solar panel installed?

A: Solar panel is made up of a collection of special cells known as photovoltaic cells. These cells are joined together with copper wire and each of them can to generate 5 volts of electricity. You can install as many cells as per your requirement. These solar panel generate AC power which is converted in DC by using an inverter.

Normal installation cost of a solar panel at home is around $5000 but it is true that if you have zeal to learn you can build a solar panel of your own within $200. Making a solar panel is not much difficult but you need to follow a good DIY guide to do that.

For more information visit: http://www.howtobuildasolarpanel.info

Q: How can electrons keep being generated by solar panels?
I was trying to figure out how solar panels work today and I found that electrons get displaced in 2 layers of a solar panel by photons coming from the sun to create power. If the electrons come from the solar panel and go into the electrical grid, how are they replaced in the solar panel? Wouldn’t the solar panel eventually lose all of its electrons and stop working? Electrons have mass, so wouldn’t the solar panel slowly deteriorate?

I think solar energy is awesome and I really want to know how it works. Any help in enlightening me on this subject would great, thanks!

A: It’s because the photovolcaics are closed-loop systems. A photon will come in and basically knock an electron across what is called a “junction” and create current, but it is “caught” (really simplified version) on the other side of the junction and kind of “bounced back” into place.

It’s like Formula 1 racing or NASCAR. The car will be sitting in the Pit, just waiting to go, then will tear out, run a few laps until it requires more fuel, then stops in the Pit again, gets refueled, and just waits for the signal from the Pit Boss to get going again.

The limiting factor on solar cells isn’t the cell itself, as in the electrical circuits and semiconductors, but rather the very slow degradation of the (usually plastic) that holds each small cell in place, so that it can create a useful photovoltaic cell. Since modern plastics can be treated with UV coatings to prevent degradation, and are practically immune to water, the only thing that can really hurt them is somebody whacks it with a hammer or drops it while installing it on the roof.

They’re excellent. The south face of my roof is sufficient, along with a small vertical-axis wind turbine, to generate more power than I need, and it actually gets sold back to Sempra Energy/SDG&E.

Q: How is energy from solar panels converted to energy that can be used for solar power?
I want to do a science project where I create my own solar panels out of different materials to see which one will produce the greatest amount of energy. Is this a realistic topic if it has to be done before Thanksgiving? If so, how do I make the solar panels? How do I measure/convert the energy? Please help!

A: Your best bet is making solar water heating panels. You could make them out of copper, PVC, and garden hose, and compare which gets hotter. Check out this site for ideas. http://www.builditsolar.com/

Avoid the scams out there saying you can build your own panel for $200 to power your whole house. You can’t. There are some free instructions on the You Build It site that are legit.

Q: How many solar panels do I need to run my two bedroom townhouse without electricity from the grid?
How many solar panels do I need to run my two bedroom townhouse? Are there different solar panels? How many solar panes to produced 1 KW of electricity?

A: The issue is more complicated than you might imagine. You can learn how many kilowatt hours you use from your electric bill. This will be an average, but if you want to be off the grid, you will need a system large enough to deliver the maximum amount you use. This will not be practical, unless you have batteries on the system.

My 6 kW system delivers about 20 kWh per day, in an area where the insolation value (suns energy) is about 5. You can find your area’s insolation value on the Internet, under SOLAR INSOLATION.

My installation is situated for maximum utility, in that my ridge runs east and west, and the panels are on the south slope.

Using this information and your utility bill, you should be able to approximate the size system you need.

If your utility has net metering, you may be better off not having batteries, but spend the money on the largest system you can afford. This way you will maximize the amount of savings. Batteries cost money, have to be maintained, must be replaced every few years, and take away from the efficiency of the system.

There are many kinds of solar panels. Look them up on the Internet to learn their characteristics. Keep in mind that the system output will be only about 70 to 75 percent of the rated output. This is due to inefficiencies in system components.

Q: What direction should solar panels face if built in the Southern Hemisphere?
If solar panels were on a solar home built in the Southern Hemisphere, should they face north, south, east, or west? and why?

A: I have mine facing North. They work fine. I’m at 38deg South.

Q: 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?

A: 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/

Q: how many solar panels would I need to power my home?
or how many watts? i dont use much electricity. i have on a couple of lights and a computer, sometimes the tv. how many solar panels would i need to power those constantly throughout the day, and maybe charge batteries for night? the air, refrigerator and hot water heater i would still use regular electricity.

A: Solar panels produce DC electricity, not AC. So, they would have to charge a bank of batteries, then you’d need an inverter to convert DC to AC.

You need to find what your peak wattage is (consumption) and how long you want to run things for and work backwards from there.

Suffice to say, a roof-full of panels probably won’t be enough.

Q: How to make my microwave work only using solar panels?
Hi,
I got really interested in the whole concept of solar panels. I read a couple of articles and saw a few videos on how to convert solar energy to electricity, but what I want to know is how can I make the microwave work, only using solar panels?

What I mean, is how many Volts, Watts, Amperes or any of these do I need to make the microwaves fully functional and how many big the solar panels need to be to absord enought energy?

Thanks!

A: There’s a lot of important details, but the short answer is that you would need a system capable of supplying around 1000W, at 120VAC and capable of handling the current (which would be around 8A).

The specific requirements would depend on how you intend to use the microwave oven (i.e. how long its on for and how often you turn it on). Based on the usage you’d be able to come up with an idea of how many batteries you need (for storing the energy) versus how many solar panels you need (for charging the batteries).

In any case, it would be a fairly expensive way to heat food. Even if you made it cheap (i.e. so that the system could only be used occasionally), I’d guess it would cost at least $1000 for the inverter, batteries and other electronics plus another $1000 for a (relatively low power) solar panel.
If you wanted to make it more of an ‘on demand’ system, you’d be looking at a pretty high price tag.
You’d probably be better off with a solar cooker.

That being said, such a system would be able to power many other household things as well, it wouldn’t be limited to just powering microwave ovens. However economically, solar power isn’t (currently) reasonable (assuming you have access to the grid).

Q: Solar panels for house power in the suburbs of philadelphia?
i live around there, no tall buildings around or anything. i was wondering if anybody has a house that has solar panels and if it works well and how much power it gives off. specs like that.

A: The amount of electricity your house could produce depends on the roof square footage thats facing the sun or that can have stands to angle the panels. Many people go for a system that gives them about half of their total usage. The actual amount per square foot can vary slightly depending on the pannels you get there are amorphous and crystaline as well as different formulations of the solar material. The best bet would be to contact a solar installer in your area for a free evaluation or for a quick look you can check out manufacturers websites like sharpsolar, bpsolar and I believe home depot also installs solar now.

Q: A good brand of solar panels for my house?
I want to install solar panels in my roof and most installers don’t recommend any particular brand. Do you have experience with any particular brand that has worked for you or anybody you know? Does the brand of the panel make a difference?
I’ talking about photovoltaic panels. I’m interested in connecting to the grid and getting the benefits that my state (Arizona) is giving to individual homes. Thanks for asking.

A: Bp380j Bp 80w Solar Panel (brand 80w 12v Module)
Bp380j Bp 80w Solar Panel (brand 80w 12v Module)

Ventamatic Solar Panel 10 Watt, Model# VX SOLAR PANEL
Ventamatic Solar Panel 10 Watt, Model# VX SOLAR PANEL

Additional 10 Watt multi-crystal solar panel for use with Item#s 336620, 336622. … 18 x 13, Works With: Solar Fans, Solar Panel

Bushnell Trail Scout Pro Solar Panel Accessory 119750C
Bushnell Trail Scout Pro Solar Panel Accessory 119750C
PANEL (CLAM) $59.95
B&H Photo-Video-Audio

Note: This is just a partial list. However, a brand does not really matter for solar or wind power. Most of them comes after the testing done by the government. Also if you can find local electrician to suggest how to get second hand panels for your house would be even better…

Q: Do I only need solar panels to have energy in day and through the night?
So I want to go completely solar. Do I need the connected solar panels alone for after sundown hours; Do I need something else in order to have energy to run my entire house throughout the night?

In other words do solar panels store the energy for after sun-down or do I need other devices to store the energy?

A: Most of the other answers are correct but not comprehensive.

Solar panels produce electrical energy or heat energy but do not store either type of energy.

Solar heat energy can be used in residential systems for hot water and space heating (also keeping a pool hot). Whether passive or active systems, you need some sort of “thermal storage” usually a big insulated vat of water that heats up when it is sunny and cools down as you use the heat. It is not economical to produce electricity from this energy in residential systems. (btw passive systems should be designed into the house when built and essentially the entire house is designed to collect solar energy and be the thermal storage system — passive systems are almost impossible to retrofit into existing houses)

Solar panels made up of “photovoltaic cells” (PV) produce electricity directly. However, the electricity produced is a direct current (or DC current) like common household batteries or automobile batteries. Not in an “alternating current” or AC like normal household current. So it must be converted to AC to run most common systems. However, if you are going to use only solar energy it may be cost effective to switch to 12 volt DC lighting …and other systems to save on some of the complexity because any time you begin running systems like DC to AC converters or rectifiers you loose energy.

To store solar made electricity you can use batteries.. like “wet cell” automobile batteries (or more likely deep cycle marine batteries which are designed for long slow discharges)…

Alternatively, as one other person suggested you can “sell” the power to the power company and buy it back at night. One issue is that typically you sell it to the power company for a cheap rate and buy it back at a more expensive rate… so be sure to include the actual rates in your estimates of cost. This type of system also has a safety backup.. you can always buy power from the electrical company if it rains for days and you cannot produce the power yourself.

Hope this helps

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