Is solar energy practicable?

Question

According to Wikipedia, it takes more energy to create a solar panel than that panel will create in its lifetime. Is this true? I can't think of any other reason why every rooftop in my home of the American Southwest wouldn't be covered with solar panels.

Answer 1

There are essentially three methods of employing solar energy.

1. The central station where solar energy is used to generate steam which runs a turbine to produce electricity.
This system, obviously, runs only in the daytime when the sky is not overcast. Given the energy density of sunlight at ground level, the efficiency of the mirrors (which must be kept clean and rotating to match the sun's movement), and the efficiency of the thermal cycle, land requirement for a system to provide electricity for a town of one family houses (in other words, low density housing) is about six times the land area of that town. Six out of every seven acres of the town would be devoted to the solar system.

2. Solar heating of water.
This is used all over Israel and works very well. Water is allowed to naturally circulate between a tank on the roof and a series of copper tubes, also on the roof. The sun heats the copper tubes which heat the water which flows back to the top of the tank, allowing cooler water at its bottom to be reheated. As long as you keep the copper tubes relatively clean, you have enough warm water in the morning for some showers and hot water later for the laundry.

3. Conversion of sunlight to electricity.
These units have a few interesting drawbacks at the moment. To begin with, they are expensive to build. Secondly, going back to the low energy density of sunlight at roof level, it would be doubtful if you could ever generate enough electricity to power your house. The covers on the units must be kept very clean for sunlight to get through. That means regular trips onto the roof with all the dangers involved. When the units eventually fail, they must be disposed of. That sounds easy until you realize that the conversion units all use rare earth doping of the selenium wafers. The most commonly used rare earth is arsenic. Yes, it is a poison and it has no half-life which would allow decay. Where would you like me to put my (hypothetical) load of arsenic?

With all that said, I sincerely hope that efficiencies improve enough that solar energy can be used to take a decent bite out of the energy production that comes from fossil fuels.

Answer 2

Solar Energy IS practicable. If you were to make one solar cell at a time, yes it would cost more energy then the cell could ever produce. However many cells are made at the same time.

With solar you need to set down with a spread sheet and do the math to see if it is practicable or not. Most people take the cost of the system add on the cost of the loan and say that it will cost more in monthly payments then the current electric bill.

That is bad math.

You have to add in the inflation rate of energy which is double what the normal inflation rate is. A Grid tied system back feeds the electric grid so you do not have to be home to get a pay back. Normally electric rates are higher at noon and that is when a solar electric system puts out the most power. If you sell your home you will add in the price of the electric system so you get a pay back for the complete system. That means you get all your investment back plus all the years you used it in free electric.

Did you know that you pay sales tax on every kWh you buy from the electric Co. while there is no sales tax on the kWh you make with your own system.

Everyone wants to own their home because renting a home is money down the drain. You can not sell it when you move so wasted money. Same for Solar Energy. Why rent your heat or your electric when you could own it and when you move you can sell it and get your money back.

Do the math..

Someone above said to nuke the world is the only way.. Well I wonder if it is ok with that person if we place the nuclear waste in his back yard? And if he and his family tree for the next 10,000 years will gaurd it for us? Keep it cleaned up when it starts leaking? I bet he would not... Nuclear cost the tax payers more to build the plant and store the waste then the plant could ever pay back.

If everyone would put solar on their home our hydro power along with wind and solar would supply all our needs. Remember the sun is always up some where in the world. The wind is always blowing some where in the world and water is always running in our streams and rivers. Coal is safer then Nukes will ever be.

Answer 3

Solar panels are good for areas that do not have electrical power easily available, and you have a lot of sunny days. It is NOT cost effective in other places. To equip a typical home for 100% power would require panels (Probably 12-16 panels covering about 300ft2, a charge controller, Battery bank of about 12-16 large golf cart type, Distribution controller, and gas or deisel generator (10-20 KW). It will cost $25,000-$40,000 and would not support air conditioning or heat. Panels probably need replacement every 6-10 years. Batteries only last 3-5 years. Both are very expensive to replace. Even with this, you will suffer some inconvienence.

I get so weary reading and seeing all these so called "environmentalists" spouting the attributes of solar power as a viable alternative. It is not because it is NOT COST EFFECTIVE for most of us.

Answer 4

What if I got that energy from a solar panel... Ha!

Just kidding. I have no idea, and quite frankly it doesn't make a difference to me. I would install one if I could recoup the cost in a reasonable amount of time. I highly doubt this is true though.

BTW, to produce really large amounts of electricity from solar energy, a collection tower would be used (like in the movie Sahara except boil water to turn turbines). These can be around 30% efficient and converting ALL the energy in that area to electricity, and I think it is something we should be doing if it leads to stabilized energy prices.

Answer 5

Besides cost, another problem with solar energy, at least around here in the north east is that the building codes do not allow battery back up. The problem is with proper venting of the hydrogen gas that is created from charging batteries. With out battery back up, the system becomes useless for residential applications. Most people are not home during the day, they are at work. Since no one is home, no need for energy. And since we can't store it in batteries, it's senseless. For commercial office buildings, it's fine because they are open during the day with all the lights on. Before doing anything with solar, check with your local authorities to see if battery back up is allowed.

Answer 6

They are expensive. Right now, they cost about $9 per watt to install. So for a typical house it would cost you $18,000 to install solar panels that would save you about $800 / year in electricity. The cost to install a system really needs to be about $3.5/watt to be economically viable.

However there are new technologies called thin films on the horizon that promise to reduce those costs. Look up CIGS or CdTe, which use a lot less material than the expensive silicon wafers required by a traditional polysilicon system.

Answer 7

There is a big problem with solar energy. 1.If the sun is behind dark clouds will barley or even not work 2. When the sun burns out we can not use solar. Dont think about lunar energy it is lit by the sun.

Answer 8

I don't know, but I highly doubt that!
It Is a fact that a solar cells pay for themselves in a few years, and they do last allot longer than that. Now whoever is manufacturing the cells is paying the same (or almost the same) for energy as you are. So how could the make a profit (and you know they are) if they are selling them for a fraction of what it costs them?
It just doesn't add up.

Answer 9

that is yet in any different case for the Elitists in government to attend to, Tax, and adjust what you do, and how you do it. rather of actually putting attempt and study into it, to return up with an extremely sustainable eco-friendly source, They throw a million/2 baked innovations into the limelight (e.g. Ethanol) by no skill accounting for the incontrovertible fact that nutrition expenditures will pass up; there is not adequate farmland interior the U.S. to enhance adequate Corn to produce even a million/4 of the crop needed, to not point out gasoline had to reap and refine it. while it takes 3 gallons to produce a million that is not very sustainable, is it?

Answer 10

Guide To Solar Power - http://SolarPower.duebq.com/?Ajn