PV Solar, etc.

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dereckbc said:
Thermal solar is less efficient than PV cells, and even more expensive to install. Several of the Thermal plants in California have been shut down because they are too expensive to operate and maintain.
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I vaguely remember reading that taken everything into account, and without any subsidies, that they produce electricity at the rate of $0.25 / kwh, which while still high, is probably better than the PV's. At any rate, the cost still has some ways to go. e/m.
 
dereckbc said:
You only got it about half right, try this link for some details.
http://www.ncpa.org/studies/renew/renew4a.html
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. Thanks for your response. I checket out the web, some of the studies sited there are dated, and I am sure there have been some progress made since then. Here is a quote from that web: "the production of concrete per thousand megawatts of nameplate solar capacity (a proportionally high input) results in carbon emissions equivalent to 10 billion cubic feet of combusted natural gas -- approximately a year's worth of fuel for a similarly sized gas-fired plant". This tells me that after a year of operation of the solar plant, the solar plant will start winning the battle of CO2 emission against the gas powered plant, as its fuel is emission free while the gas firee plant will continue to emit CO2 at a constant rate. There is no free lunch however, as the capital cost of the concentrated solar will be much higher than any fossil fueled plant, resulting in higher price per generated kwh. So the question is what price will the society bear for reduction of carbon dioxide, and how seriously it is viewed. In time though the price of technology will fall, just look at price of computer hardware in the past 25 years or so. e/m.
 
Energy-Miser said:
. I checked out the web, some of the studies sited there are dated, and I am sure there have been some progress made since then.
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Little if any when it comes to solar over the last 30-years.

Energy-Miser said:
. Here is a quote from that web: "the production of concrete per thousand megawatts of nameplate solar capacity (a proportionally high input) results in carbon emissions equivalent to 10 billion cubic feet of combusted natural gas -- approximately a year's worth of fuel for a similarly sized gas-fired plant". This tells me that after a year of operation of the solar plant, the solar plant will start winning the battle of CO2 emission against the gas powered plant, as its fuel is emission free while the gas fired plant will continue to emit CO2 at a constant rate.
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Who said it has to be gas or coal? You also overlook the fossil fuel it takes to build and operate such a plant. Takes a lot of steam energy to produce glass, concrete, copper, etc? Beside with China building a coal power plant every 3-days you loose the debate over CO2 emissions, nothing will stop it except war. The real answer in the US for reliable clean inexpensive electric power is nuclear.

Energy-Miser said:
. There is no free lunch however, as the capital cost of the concentrated solar will be much higher than any fossil fueled plant, resulting in higher price per generated kwh. So the question is what price will the society bear for reduction of carbon dioxide, and how seriously it is viewed. In time though the price of technology will fall, just look at price of computer hardware in the past 25 years or so. e/m.
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Again Solar prices have not moved in 30+years except up with regards to thermal, so the analogy is pointless. As to your question of ? what price will the society bear for reduction of carbon dioxide, and how seriously it is viewed.?

From looking at the growth of China and India, coupled with the accelerated CO2 emissions from countries signing the Keota agreement, no one takes it seriously as it cannot be stopped unless you are willing to drop the bombs. :mad:
 
All power plants require lots of material to build. In terms of subsidies nuclear wins the cake. Without government underwriting, no insurance company will give it a second look. Although I am not entirely anti-nuclear, as it is essentially CO2 emission free. Regarding India and China, we still leave them in the dust in per capita consumption and carbon emission. The solution does however have to be global, as chemistry knows no political boundries. As for the bomb, I am not sure what that will do. Solar prices have come down, if you consider that at one time they were almost exclusively used by the space indusrty, far too expensive for other applications. e/m.
 
Energy-Miser said:
Regarding India and China, we still leave them in the dust in per capita consumption and carbon emission. The solution does however have to be global, as chemistry knows no political boundries.
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On a per capita basis, competing with countries where 90% of the population live in mud huts, is pointless. Boasting a better carbon footprint because most of your nation are surfs isn't much of a boast.

A better comparison would be Europe, where at least most of the population showers daily, and refrigerates their food.
 
dereckbc said:
The real answer in the US for reliable clean inexpensive electric power is nuclear.
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For a while... Demand goes up, cost goes up, and we wind up with the same problem in a few decades. Time to invest in uranium

Over the past 20 years, safety concerns dampened all aspects of development of nuclear energy: No new reactors were ordered and there was investment neither in new uranium mines nor in building facilities to produce fuel for existing reactors. Instead, the industry lived off commercial and government inventories, which are now nearly gone. Worldwide, uranium production meets only about 65 percent of current reactor requirements.

"Just as large numbers of new reactors are being planned, we are only starting to emerge from 20 years of underinvestment in the production capacity for the nuclear fuel to operate them. There has been a nuclear industry myopia; they didn't take a long-term view," Neff said. For example, only a few years ago uranium inventories were being sold at $10 per pound; the current price is $85 per pound.

Currently, much of the uranium used by the United States is coming from mines in such countries as Australia, Canada, Namibia and, most recently, Kazakhstan. Small amounts are mined in the western United States, but the United States is largely reliant on overseas supplies. The United States also relies on Russia for half its fuel, under a "swords to ploughshares" deal that Neff originated in 1991. This deal is converting about 20,000 Russian nuclear weapons to fuel for U.S. nuclear power plants, but it ends in 2013, leaving a substantial supply gap for the United States.

Further, China, India and even Russia have plans for massive deployments of nuclear power and are trying to lock up supplies from countries on which the United States has traditionally relied. As a result, the United States could be the "last one to buy, and it could pay the highest prices, if it can get uranium at all," Neff said. "The take-home message is that if we're going to increase use of nuclear power, we need massive new investments in capacity to mine uranium and facilities to process it."

http://web.mit.edu/newsoffice/2007/fuel-supply.html
http://www10.antenna.nl/wise/481/4777.html

"Pro-nuclear industry sources estimate that the worldwide uranium supply is 6.4 million tons. If we used nuclear power for 70% of our electricity generation worldwide starting now, we would exhaust this uranium supply between 2016 and 2018. That is IF we could build enough nuclear reactors to provide 70% of the world?s electricity, which we can?t."
 
LawnGuyLandSparky said:
On a per capita basis, competing with countries where 90% of the population live in mud huts, is pointless. Boasting a better carbon footprint because most of your nation are surfs isn't much of a boast.

A better comparison would be Europe, where at least most of the population showers daily, and refrigerates their food.
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And uses half as much energy doing so. As you can see there is a lot of room for improvement. Being more efficient in using energy in the smart we to go. e/m.
 
Energy-Miser said:
And uses half as much energy doing so. As you can see there is a lot of room for improvement. Being more efficient in using energy in the smart we to go. e/m.
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Yes, though I thought they used even less than 1/2 the energy we use. At any rate, I feel the reason we use so much more is that despite the recent trend, electricity and oil is still relatively cheap in America. We're bitc$ing about $3.00 a gallon gas, when Europe has been paying much more for decades.

Room air conditioners are sold for $69.99 off the shelves in drugstores. I know more than a few people who sleep with the a/c on whether it's needed or not, because "I can't sleep without it." I don't know a single person who ever purchased a new refrigerator and didn't get the absolute largest model they could fit. The trend is and has always been bigger is better. Ever get a new computer with a SMALLER monitor?
 
LawnGuyLandSparky said:
Yes, though I thought they used even less than 1/2 the energy we use. At any rate, I feel the reason we use so much more is that despite the recent trend, electricity and oil is still relatively cheap in America. We're bitc$ing about $3.00 a gallon gas, when Europe has been paying much more for decades.

Room air conditioners are sold for $69.99 off the shelves in drugstores. I know more than a few people who sleep with the a/c on whether it's needed or not, because "I can't sleep without it." I don't know a single person who ever purchased a new refrigerator and didn't get the absolute largest model they could fit. The trend is and has always been bigger is better. Ever get a new computer with a SMALLER monitor?
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And how about those houses you see under construction? Some could house four families easy!
 
Energy-Miser said:
And how about those houses you see under construction? Some could house four families easy!
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All I know is, my next house is going to be SMALLER not LARGER. I need a den, a library, a media room and a rumpus room like I need a hole in my head.
 
LawnGuyLandSparky said:
I need a den, a library, a media room and a rumpus room like I need a hole in my head.
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I must have a hole in my head, then, because I love my home theater room. :cool:

It's the reason we chose this house. (It was just a finished basement room back then.)
 
LawnGuyLandSparky said:
All I know is, my next house is going to be SMALLER not LARGER. I need a den, a library, a media room and a rumpus room like I need a hole in my head.
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Amen. Once my two boys are out on their own (a few years), we will be downsizing too :)
 
Energy-Miser said:
I vaguely remember reading that taken everything into account, and without any subsidies, that they produce electricity at the rate of $0.25 / kwh, which while still high, is probably better than the PV's. At any rate, the cost still has some ways to go. e/m.
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PV is $10K per KW for the first KW. At 5 hours insolation, that's $2K per KWH from the array, divided by 0.80 end-to-end efficiency is $2,500 per KWH. Each KW after the first goes down in cost as all of the parts are required even if you've just got a single panel on the roof.

All that's left is deciding how many days the hardware lasts and you've got the cost. For larger systems -- 3KW arrays -- I've heard the cost per KWH is about $0.22. Not the most cost competitive, but I pay $0.14 / KWH as it is. I used 15KWH yesterday, so the difference would be 15KWH times the cost difference -- 15 * $0.08 = $1.20. I think I can afford $1.20 a day ...

(And I just checked my logs from yesterday -- 77% efficient from the array to the inverter outputs.)
 
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LarryFine said:
I must have a hole in my head, then, because I love my home theater room. :cool:

It's the reason we chose this house. (It was just a finished basement room back then.)
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Ideally, I want a very large open floor plan kitchen, living and dining, large enough for fireplace pit, bar, media and all the daily stuff. Two bedroom "suites" master & guest, and a 4-car garage with a loft above. Throw in a USABLE porch and I'm satisfied.

Impressive vaulted soaring ceilings and 2nd story "bridges" across 1st floor spaces are all fine and good, but they're little more than "wow factor" that require heating, cooling, lighting, and furnishing for what amounts to dead, little-used space.
 
tallgirl said:
PV is $10K per KW for the first KW. At 5 hours insolation, that's $2K per KWH from the array, divided by 0.80 end-to-end efficiency is $2,500 per KWH. Each KW after the first goes down in cost as all of the parts are required even if you've just got a single panel on the roof.

All that's left is deciding how many days the hardware lasts and you've got the cost. For larger systems -- 3KW arrays -- I've heard the cost per KWH is about $0.22. Not the most cost competitive, but I pay $0.14 / KWH as it is. I used 15KWH yesterday, so the difference would be 15KWH times the cost difference -- 15 * $0.08 = $1.20. I think I can afford $1.20 a day ...

(And I just checked my logs from yesterday -- 77% efficient from the array to the inverter outputs.)
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Do you have a PV system at your house? e/m
 
Energy-Miser said:
Do you have a PV system at your house? e/m
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Yes. Just don't tell it that it's a PV system. It thinks it's a 10KW Generac!

The attached JPEG shows the graph from the 27th. Blue is house load, green is the inverters, red is the PV array. I don't think they are in the same scale. I forget ...
 
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tallgirl said:
Yes. Just don't tell it that it's a PV system. It thinks it's a 10KW Generac!

The attached JPEG shows the graph from the 27th. Blue is house load, green is the inverters, red is the PV array. I don't think they are in the same scale. I forget ...
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Thanks. yes looks like it must be out of scale for the three loads. Do you have a 10kw system? Batteries? Are you off grid? e/m.
 
cschmid said:
I do not know about cost effectiveness of electricity on PV systems but has anyone used them for water heating? does anyone have good info sources for PV systems..
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NREL (National Renewable Energy Laboratory) has some basics. BP as a big producer of pv cells has much on their web.
 
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