Solar Power

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pmconusa
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Solar Power

The Canadian solar power authority has determined the sun provides approximately 1000 Watts of radiant energy to the earth per square meter under conditions of high noon and 25°C. The most efficient solar panel can convert this energy with an efficiency of about 15.4%. In other words, the best solar panels made to date can extract about 154.4 Watts of DC power per square meter of panel surface. This is under ideal conditions when the sun is highest in the sky and at an ambient temperature of about 25°C. It is less as the sun comes up and goes down and if it is cloudy.
The average U. S. home uses approximately 30 kWhrs. of energy per day. If this is evenly divided through the day it works out to about 1.25 kW per hour. It would therefore take just over 8 square meters of solar panel to meet the average requirements. But, our electricity use is not uniform. For example, a 1200 BTU air conditioner uses approximately 1200 Watts of power when it is running. To run just this one appliance would require 7.8 square meters of panel and it would be available only in sufficient quantity at high noon on a cloudless day.
If this amount of energy were stored so it could be used as needed through the use of batteries the most efficient of which are 90% efficient in their storage of energy and you do not have air conditioning, you could expose about 216 square meters of panels ((30,000/154.4)/.90) for one hour at noon on a cloudless day, hoping tomorrow you would have the same luck. This would be Direct Current power and all of your appliances would have to work on DC or you would have to lose some of this energy in converting it to AC.
It is therefore conceivable that a family of four could sustain themselves if they could afford not only the 2300 sq. ft. house but the 2300 sq. ft. of roof solar panels and the kilograms of lithium ion batteries that would periodically have to be replaced.
The world is not this simplistic and energy use is not confined to homes but commercial and industrial uses as well as motor vehicles. Common power plants have generators ranging in size from 100,000 kW to 1,500,000 kW in size. To replace these with solar panels would require nearly 650,000 sqm. and 10 million sqm. of solar panels and their rechargeable batteries would require more lithium than is known to exist. This does not include the material required to produce the panels.
When you strip away the hype and examine the practicality it is clearly obvious that obtaining our energy needs from the radiant energy from the sun is utterly ridiculous. The same can be said for wind power and for that matter, the colonization of other planets in the universe. It is all about jobs, because the economic system we have adopted requires one to work in order to obtain the exchange necessary to survive. It is doomed to fail as it has in every society that has adopted it. Yes, Mel and Bruce, it’s all in the “book”.

Ugenetoo
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I don't completely agree with

I don't completely agree with your numbers, but you are spot on with the conclusion.

Melvin Udall
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Just what you'd expect from

Just what you'd expect from someone who made his fortune in the fossil fuel, global warming business, all while enriching the Wahabbists in Saudi Arabia.

So just for grins, pmcon, when your new economy is in place, where do you gas up your car, buy the tires, and get it repaired? And where are the parts for the repair shop made, and by who? Do you buy insurance? Do you get it licensed? And on what highways do you drive it, and where?

Bruce Libby
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I thought you were giving up

I thought you were giving up on converting me ?
If so stop addressing me in your posts.

pmconusa
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Ugenetwo: These are not my

Ugenetoo: These are not my numbers but those of people in the industry. If these are incorrect, what are yours?

Melvin Udall
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And what is the meaning of

And what is the meaning of life? I've asked multiple times. Aren't you interested in debate?

Or is the meaning of life explained in the book?

pmconusa
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This is the first time I

This is the first time I recall your posing this question but, on the other hand even if it isn't, the meaning of life or, as Webster puts it, the purpose has no definitive answer and therefore a debatable subject without a uniformly agreeable conclusion. Do you have any other comments on the subject of this post, or don't you want to enter the "debate"?

Melvin Udall
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Through deep study over my

Through deep study, I have come to realize that the meaning of life is a wheel.

johnw
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Wow,just imagine if someone

Wow,just imagine if someone could split an atom and access all of that power .........or maybe figure out how to use water and gravity to generate power........

anonymous_coward
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Well for one, the solar

Well for one, the solar constant is 1370 W/m^2, not 1000, and the surface temperature makes no difference in that regard.

anonymous_coward
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Also, you are neglecting

Also, you are neglecting large scale solar installations - keep in mind there are vast tracks of empty space in our and other countries. I would also suggest that Canada is probably not an ideal place to run solar power given its high latitude.

pmconusa
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In one of my early

In one of my early engineering classes one of the students asked how long would an extension cord have to be before the energy you put in at one end equaled zero at the other? The professor opined it was a useless but interesting question. Useless because no one would pay to create a wire of a length where the resistance imposed by the material (copper or aluminum) would result in 100% of the energy being employed would be used to overcome the resistance such that there would be nothing coming out at the end.

It is why we build power plants close to the demand as some of the energy being generated is lost heating the wires that carry the current. It seems apparent that anonymous overlooked this fact because he seems to justify building wind power turbines in the ocean or on mountain tops and solar panels in barren land while ignoring the losses involved in transmission.

I would advise anonymous and others of his ilk that there is no free lunch, perpetual motion or 100% energy conversion.

Melvin Udall
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You have to transmit the

You have to transmit the power generated at a distance by radio wave to eliminate the copper losses.

Toolsmith
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Radio Wave transmission would

Radio Wave transmission would have its own losses.
Maybe a giant laser? ;-)

Melvin Udall
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Magnetic induction might work

Magnetic induction might work. Or waveguides.

Islander
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Bring back nuclear power,

Bring back nuclear power,

Toolsmith
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Quantum Entanglement? ;-)

Quantum Entanglement? ;-)

Ugenetoo
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Is that what the mess

Is that what the mess Weinstein's in called?

Melvin Udall
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And lets not forget fiber

And lets not forget fiber optics for lossless transmission.

pmconusa
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Just as their is no cold

Just as their is no cold fusion there is no 100% energy conversion. We had fewer losses in transmission because copper was a better conductor than gold and cheaper. Then when copper became more expensive we switched to aluminum. All of them are tradeoffs, cost against energy loss. Even if we could convert the sun's energy with 100% efficiency and lose nothing in transmitting to where it can be used there is not enough to power all the devices, including illumination.

anonymous_coward
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Holy shit you guys are insane

Holy shit you guys are insane. They transmit electricity via high voltage AC (not DC, which declines rapidly due to resistance) at such a frequency so as to minimize the impedance.

(Impedance, as you'll recall, is the component of resistance that affects alternating current. It is represented as the imaginary component of the complex number - the real component representing resistance.)

Melvin Udall
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As I recall....but what do I

As I recall....but what do I know....they transmit electrical power at high voltage to reduce the current in the lines, which reduces the copper loss, and allows the use of far smaller gauges for long distance runs. Take a look at the wires on your street; the wires on the poles carrying the power are quite small in size, and then following a stepdown in voltage by the transformer that feeds your property, the wires to your house are of considerably higher gauge.

Resistance in such transmission is where the losses come into play, and the lower the voltage, the higher the current required to deliver the same power. Look at the cables coming off your car battery. It's not unusual to have 30 amp or higher fuses in your car.

Other than high energy users like an electric oven or dryer, it's unusual to have higher than a 20 amp breaker in your house.

I'm not aware that DC has greater losses than AC all other things being equal.

But my degree is a long time ago, and I'm sure the laws of electricity have been significantly updated by now.

pmconusa
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DC Transmission incurs fewer

DC Transmission incurs fewer losses but since we opted for AC we are stuck with having to employ inverters on DC transmitted power which greatly increases its cost. The government had an experimental 1 megavolt facility near the Bonneville Dam in Washington. It was the early battle of Edison with Tesla over which form of transmission to use and Edison won and General Electric made a mint as a result. Even 60 cycles was a question for AC. I remember when I worked for Allis Chalmers we had a 25 cycle generator that powered much of the equipment at U. S. Steels Gary Indiana plant back in the 1950s. When they shut it down for overhaul they had to crank up some of their old blast furnace gas engines. They were really a sight having flywheels that weighed over 50 tons.

anonymous_coward
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Sorry it's been like 20 years

Sorry it's been like 20 years since I've thought about these things... it's easier to step down the voltage when you have AC compared to DC.

So, high voltage reduces losses, and AC is chosen because it's easier to step it down. 60 Hz is chosen to reduce loss due to radiation (this is what I was thinking of, sorry have been burnt out).

pmconusa
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Anonymous: I suggest you go

Anonymous: I suggest you go back and retake your lessons in physics. Voltage is like pressure. If you input 1000V at one end of a wire there is a length of wire of a particular material that conducts electricity at which the voltage at the other end will be zero, the pressure having been reduced by losses during its flow through the wire, mainly in heating the conductor. The same is true for water flowing in a pipe.

In a clock or watch, driven by electric power, be it battery (DC) or generator (AC) the electricity is used to vibrate certain minerals or elements that have a consistent frequency when excited by the electricity. These vibrations occur at a specific frequency and those vibrations are then translated by mechanical means to drive the clock's display. Cesium is the accepted standard and is considered the atomic clock. It is used because it can be adjusted for accuracy such that is will gain or lose the actual time in the longest accumulated time. Purely mechanical clocks, such as grandfather clocks are adjusted by lengthening or shortening the pendulum that swings at a given frequency. The invention of the escapement mechanism allowed this same principle to be applied on a much smaller scale and hence the wristwatch, until recently a purely mechanical device. The internet has some interesting and informative articles on the telling of time and in the process explain the workings of these instruments.

In reading through some of your other posts on this thread you alluded to the apparent incorrectness of my citing the radiant energy as 1000 W per square meter and your claim it is 1370. These numbers are both right as would any number between 0 zero and about 1500 or so. That it is because it depends on the time of day which determines the angle at which the energy enters the atmosphere and the amount of atmosphere the energy has to pass through to reach the earth. It is immaterial in any event because it is insufficient to power the devices currently being employed and unless people are willing to forego those devices, solar power will never suffice to replace fossil fuels. When we run out of non-renewable fossil fuels we can always turn to burning wood that is renewable or hydropower that also has its limits and like wood dependent on rainfall.

anonymous_coward
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.... must ... resist...

.... must ... resist... temptation.... to .... correct...
... eat .... more ..... kCals.....

pmconusa
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Remain silent and only be

Remain silent and only be thought a fool, respond and you remove all doubt. I see nothing wrong or demeaning in correcting errors or assumptions. Lies and falsehoods take on the meaning of truth when repeated often enough. It is how the Progressives have gained control and we have stood by and allowed them to do it without challenge.

Melvin Udall
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Does such wisdom apply to you

Does such wisdom apply to you, or just others?

pmconusa
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It applies especially to you

It applies especially to you as your commentary clearly illuminates.

Melvin Udall
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Physician, heal thyself.

Physician, heal thyself.

taxfoe
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One guy's 5 year, cost

One guy's 5 year, cost benefit analysis of his home solar installation.

YOUTUBE 08:23

It pretty much mirrors everything I've heard from people with private systems . . it's a good idea.

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