Archive for February, 2010
How much less solar energy is received at 60 degrees latitude than that received at the Equator?
At 60 degrees latitude (north or south), and averaged over a year, the solar energy level is about 50% to 55% of the level at the equator. That’s not counting the effects of clouds.
A lot of the thermal energy at high latitudes comes in on wind and water movement; I guess you could say that is also a very indirect solar energy.
I was thinking on buying some solar panels but I wanted some real life first hand knowledge.
It really depends on your usage habits, and the size of the system installed. For instance, if I got a modest-sized solar array, then said, "Woo-hoo, now I can run the A/C all summer and electric heaters all winter!" then I might never turn the meter back.
Now for the data points. In August 2008, we had a net consumption of -214 kWh for our house (that is, the meter was turned back 214 kWh). That’s the summer, of course. In January 2008, the dead of winter, we used a net 331 kWh. Other months are between these two extremes. Over the course of a year, it balances out to about zero kWh used. But again, if we changed the size of the system only slightly, or altered our usage patterns only slightly (say, it was a very cold winter), the answers would be different.
If you want to see our bill in detail, send me an email.
The more, the better. The arguments should be at least remotely feasible. I’m looking for ecological arguments why Solar Energy is a better alternative than Nuclear Reactors.
Just list as many as you can come up with.
Its all about the "after life" of the energy source. With solar panels there is some carbon and other things that can (hopefully) be reclaimed and recycled. With nuclear power you get things like Yucca Mountain. However, unless we invest in breeder reactors and breeder nuclear fusion to enrich the uranium waste into plutonium. This is great because the waste that would other wise be carted off to Yucca Mountain gets recycled.
Plutonium caries a stigma due to the fact that it can be easily weaponized. More over breeder plants use liquid sodium. Liquid sodium is highly volatile when exposed to air or water. They can also be cooled using helium.
The down falls of solar are that the productivity will decrease with the age of the panels. disposal (nothing like radio-active storage). And power generation at night (overcome with the use of solar towers).
Solar power generation has very little environmental impact beyond mining the resources, manufacturing, and disposal.
Best of luck.
I live in india. My house has 5 ceiling fans, 1 TV, 1 refrigerator, 1 washing machine, 1 electric motor for pumping water, 1 electric iron, 1 electric heater for heating water, 8 tube lights, 6 bulbs. Also tell me how much will it cost me to have these solar panels installed in indian rupees. Also tell me where to get these panels in india. Thanks
I’d suggest checking out…
http://earth4energy-manual.com/blog/
watch the free video review of one of the most popular guides to building your own source of alternative energy.
Hope it helps & Good luck!!!
- Katie : )
I’m doing a project in Science Club and me and the other people in club are wondering about how we could convert solar energy into electrical energy on a system?
A solar panel would be a good idea.
Can u guys help on how solar panels work and how it generates electricity?
(or u can give me a good website that has solar panel info on it)
~Thanks in advance!~
Solar panels are made up of a number of solar cells. A solar cell will generate from 0.5 to 0.55 volts DC and a current depending on the size and type of cell. The current can be milli-amps or amps. We have a list of solar cell manufactures on our blog http://brutuscontry.com under products that are sorted by watts per area. Also go to wikipedia to get more detailed information on solar cells.
Solar cells convert the energy of incoming light to electric energy; a good quality cell operates at an efficiency of 15%. Each person in the United States uses energy (for lighting, heating, transportation, etc.) at an average rate of 11 kilowatts . Although sunlight varies with season and time of day, solar energy falls on the United States at an average intensity of 200 W/m^2.
Assuming you live in an average location, what total solar-cell area would you need to provide all of your energy needs with energy from the sun?
The correct rate is 11kWhr per day. 11kw would be a horrendous amount of power.(maybe Al Gore uses it at this rate)
I will calc it at your rate for problem sake. (this is not real life by the way, there are lots more variables, length of day, etc)
200W/m^2 * 15% = 30w/meter
11kw / 30w/meter = 366m^2
On a side note I think mastering physics is a crappy program, made for lazy physics teacher that dont ever care about application of knowledge.
I have an xbox 360 and an older tv that I would like to get solar panels for because my mom is mad I am running up the electric bill. I know nothing about solar panels and I want to know what I need to make this all work. Any suggestions would be great.
Your first problem is that the solar panels will only work properly outside, so you will have to run a power cable either through an open window or through a hole in the wall, which will make your mother even madder. Next you need to consider the specification of the solar panel. The older TV is likely to run only on mains voltage rather than 12 volts, so you will need a panel that puts out 12-14 volts DC to charge a battery, which in turn supplies an inverter which produces a mains voltage of 110V or 240v AC (whichever country you are in). It will all get rather expensive.
Why can solar energy be not used everywhere? Is it very expensive to tap it?
Solar energy is (or was) very expensive, yes. That is changing. current costs versus long term power production are falling, however. At present, the cost is borderline.
However, solar energy alone is not a complete answer. First of all, for the production of electricity, it has some problems. The main one, of course, is tha tit doesn’t work at night. You either need a storage system (batteries) or an alternative source when it’s dark or cloudy.
There are alternatives which, combined with solar energy, can replace coal. Wind, existing hydroelectric systems, nuclear energy, and tidal power are some of them.
Myy point is, don’t fall into thhe trap of fixating on a single all-encompassing cure-all technology. We need a mix of technologies. That’s true today–we use coal, oil, nuclear, hydroelectric, and other sources–a mix of technologies to provide our energy needs. We need to change themix–eliminating fossil fuels and incorporating new technologies to replace those fossil fuels. There is no simple solution.
Now-as to oil–it is used primarily for transportation. In some ways it is ideal: its easy to store and the fuel stores the energy, whichis released when it’s burned.
There are alternatives. The one I think the most practical is to use electric cars. Current technology makes electric cars with performance and adequate range possible at prices comparable to gas-powered cars (once they are produced in large numbers as gas-powered cars are). That’s acutally a solved problem. What we do not have is a way of producing the electricity to power all those cars (without buring oil or coal, which defeats the purpose) at present. For that–go back to the first part of this post.
But we also do not have a practical infrastructure to deliver that electricity to a fleet of 150 millioncars (in the US). That is not a trivial problem. Think of what it takes to deliver a gallon of gas from an oil well to your car. Here’s the sequence. Oil well to pipeline (hundreds of miles) to refinery to another pipeline to atanker truck to an gas storage tank under a gas station and then a pump to take the gas out o fthe tank and deliver it to your car.
And remember, you need tha tinfrastructure so comprehensive that it blankets an entire CONTINENT.
You will need the samme for electric cars (or any other alternative).
I don’t mean to discourage you–this is doable. We DID do jsut that in the early 20th century to make our current system of gs-driven cars possible. But that took decades–and a hellava lot of engineering and research.
But–as to your question–we wil get solar power on a large scale in the foreseeable future. But we will need a lot more. It’s a complex problem–and a big one.
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?
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