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RE: Alternative Fuels Roundtable - 4/20/2008 7:32:43 AM   
Hippiekinkster


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Inexpensive bicycles mass-produced from carbon fiber. Bike lanes built into the sidewalks or roadway medians. X-tunnels at busy intersections. Covered commute lanes for bikes on freeway medians. Train/subway cars for bicyclists, like in Europe. Trams in central business districts.

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RE: Alternative Fuels Roundtable - 4/20/2008 7:33:19 AM   
lronitulstahp


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quote:

 I just got back from my father's funeral in Illinois a couple of months back, and the big brouhaha up there is that an energy conglomerate is buying up 2 acre lots in lines all over the central part of the state to put up windmill generators. Clean, simple energy that produces no pollution. Yet, the residents there are digging in their heels, since it will mean the loss of several hundred acres. It's bizzare to me that there should be such resistence. I wonder how they'd feel if the company intened to put another nuke plant in their back yards instead? 
  Perhaps these energy conglomerates could learn a lesson from the Europeans in this case.  In Germany, electric windmills(every one i saw was made by GE)are put on land rented from farmers.  The farmers grow crops underneath and around the windmills, and make extra money by allowing the windmill to be put on their land.  Win-Win.  The problem here is..."conglomerates" aren't very good at sharing.

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RE: Alternative Fuels Roundtable - 4/20/2008 7:43:03 AM   
bipolarber


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Yeah. I think more public transport would be a good thing. Now that we are spending $12 billion in Iraq every month, I just thought I'd point out that the train industry looked into what it would take to build a high speed mag lev train to run from coast to coast...

Yup. About 2 months in Iraq's worth.

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RE: Alternative Fuels Roundtable - 4/20/2008 7:57:25 AM   
Padriag


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Solar power is a viable possibility but there are a number of challenges to be overcome.

First, at the moment its horribly ineffiecient.  Current solar cells only convert about 12% of the energy they capture... to be effective they need to be capturing closer to 50%.  There is some research being done in Germany with materials that could get close to this, capturing somewhere around 38% which is an astonishing leap.  The down side is the cost of materials.  That's the other problem... solar cells are expensive.  While costs are being reduced as new materials and more importantly more efficient manufacturing methods are being developed... it is still cost prohibitive.  To install solar panels sufficient to power a 2000 sq ft, 3 bedroom, 2 bath home would probably cost somewhere between $30,000 to $40,000.  Not so bad if you are building or buying a luxury home... but not so accessible for middle income family.  For example, where I live (SW Virginia) that same home might list for anywhere from $65,000 to $120,000 depending on the location.  Adding solar to the cost of the home would make it prohibitively expensive for most middle income and lower income home buyers.  Virginia does have quite a few incentive programs, including federal grant money, available to help with the cost and I've been looking into these for some of the homes I'm putting on the market.  I'd really like to be able to sell affordable, energy independent homes... but so far it just hasn't been economically feasible.  Solar hot water heating does seem practical and affordable at this point and I'm looking into at least including that much in the future.

You can't really set asside the idea of profit... stuff cost money and somebody somewhere has to pay for it.  Governments are typically the worst to pay for it because they're the least efficient and tend to pay far too much.  So while government grant money seems nice for the moment, in the long term it actually helps keep the cost up.  Why should solar cell manufacturer's lower the cost when they know a home owner can potentially get up to $20,000 in federal grant money to pay for it?  Drop that off and you'll watch prices drop as well.  Like it or not, for solar power to become a viable energy source, it will also have to become an economically viable energy source... its just how things work.

Nations sharing things?  You truly are an idealist...

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A stern discipline pervades all nature, which is a little cruel so that it may be very kind - Edmund Spencer

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RE: Alternative Fuels Roundtable - 4/20/2008 8:17:54 AM   
Padriag


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quote:

ORIGINAL: lronitulstahp

Perhaps these energy conglomerates could learn a lesson from the Europeans in this case.  In Germany, electric windmills(every one i saw was made by GE)are put on land rented from farmers.  The farmers grow crops underneath and around the windmills, and make extra money by allowing the windmill to be put on their land.  Win-Win.  The problem here is..."conglomerates" aren't very good at sharing.

Oh there are all sorts of incentive programs and grant money available in the US to do these sorts of things and yet the majority of people in America not only don't take advantage of the programs available... they don't even know they exist.  The biggest problem of all is apathy.  Your average American just doesn't care enough to put the effort into it.  If I build or remodel a home and equip it with solar energy, they'd buy that provided it doesn't cost too much (which currently it does in the market I work in, I focus on lower or middle income housing)... but don't ask them to get off their arses and do it themselves.  They love to bitch about how the corporations are ruining everything, or else its the government at fault, or else its capitalism, or some other such thing... the one person they don't like to blame are themselves.  It ends up falling to the few to solve the problems of the many... which is pretty much how its always been the world over.

So you get guys like me working in a depressed economy, a depressed housing market, trying to provide affordable quality housing for lower and middle income families, trying to make those homes as energy efficient as possible, trying to find ways to make solar power affordable, and on top of that trying to line up financial assitance to buyers, low interest bank loans, SPARC incentives, VIDA incentives, etc. to help people buy homes.

Why... because most people are either too lazy or too stupid to do it themselves.  No matter how much you help them, they come back wanting more.  I look at houses I sold just a year ago, nice clean, modern, beautiful homes that I put a lot of effort into... and they're trashy now, unkempt, unmaintained.  People don't care... we're a throw away society that doesn't value much.  Sometimes I think maybe the best thing would be to scrap welfare, soc sec, all those incentive programs, all those aid programs and tell people ya gotta work to eat... you have to earn every last damn thing you get or you get nothing... maybe then people would act like they give a damn about what they have, take better care of it.

Sorry, I'm ranting and its going off topic.  Just feeling a lil frustrated because I do genuinely give a damn.  I've put some very long hours in the last two weeks on a project, I'm tired. 

Solar energy is a good idea, one that has to potential to be developed far beyond what most might imagine.  But it is also still a developing energy source, one that still needs a lot of work before its going to become really useful.  Solar cells are going to have to become a lot more efficient... and durable (one good hail storm and there goes your million dollar solar power farm).  Materials and manufacturing costs will have to be lowered, and like it or not, the government grants need to be weened off to allow market dynamics to kick in and force costs down further.  Personally, I'd love to see every house I do next year be fully solar powered and energy independent... but I doubt it'll happen... at least not next year... maybe in 10.

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A stern discipline pervades all nature, which is a little cruel so that it may be very kind - Edmund Spencer

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RE: Alternative Fuels Roundtable - 4/20/2008 8:21:13 AM   
SugarMyChurro


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quote:

ORIGINAL: Padriag
Solar power is a viable possibility but there are a number of challenges to be overcome.


Yes, it is challenging since you didn't read the linked to article apparently...



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RE: Alternative Fuels Roundtable - 4/20/2008 8:35:15 AM   
Sanity


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Nah, the water isn't destroyed, it makes its way back down to the ocean.


quote:

ORIGINAL: Padriag

Ironic you should mention that... increasing both the consumption of fresh water and the salinization levels of the oceans will accelerate global warming... which will indeed increase ocean levels, change shore lines and then trigger an ice age... eventually.  But hey... why worry, let the grand kids deal with it...


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RE: Alternative Fuels Roundtable - 4/20/2008 8:57:08 AM   
Padriag


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Oh I read... I'm also a building contractor who has actually installed solar cells, worked with the technology out there and knows how a power cell actually works.  More than apparently the author of that article can say.  The author is selling a pipe dream... concentrated sunlight won't get you any more power on anything except a cloudy day.  The reason lays in how a solar cell works.  The light photons entering the cell trigger the flow of electrons which produces electricity.  How much is produced is entirely limited by the capacity of the photovoltaic material to absorb photons... anything over that limit is wasted... period.  Currently all materials in use waste at least 70% of the photons they absorb, thus their inefficiency.  Concentrating the sunlight onto a solar cell won't get you any more power because those extra photons, having already exceeded the cell's capacity are simply wasted.  Except on a cloudy day when the amount of photons might otherwise drop below the cell's threshold.

In other words, the solar "tower" idea is thus far just another perpetual energy machine... its a fraud.

As are the claims of DIY solar kits that can power an entire house for only $250 in materials.

For those wondering how much solar cell power you need to power a home... here's some numbers.  The average single family residence according to international building codes (2006) requires about 2 watts per sq foot... except for then kitchen which requires about 4 watts per sq foot.  So a 2000 sq ft home with a 150 sq ft kitchen would require about 4.3 Kw of power hourly.  To be fully energy independent you need solar cells able to produce this, plus about 100% to 200% more during peak hours... which are about 1/3 of the day or an 8 hour period.  So you need solar panels kicking out somewhere around 8.6 to 12.9 Kw per hour, plus battery storage for the additional power you'll need during the evening, nighttime and early morning.  The solar panels alone will set you back about $40,000... plus the batteries which will cost about as much.  That's the technology we have right now, that actually exists and works and meets building codes.

Or you could read an article about the latest magic solar fairy out there and maybe if you clap and say "I believe, I believe" three times...

Trust me folks... if there was a way to cheaply build solar powered, energy independent homes there'd be building contractors lined up to do it in an instant.  Why... cause we could make gobs of money selling such homes to all the people who'd love to tear up their electric bill.  It may eventually happen, I certainly hope it does.  But what I know for a fact is, right now the technology to do so does not exist.  If it was, I'd be making some lower and middle income families out there very, very happy.

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RE: Alternative Fuels Roundtable - 4/20/2008 8:58:55 AM   
Termyn8or


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I have to go along with SMC when it comes to solar. Of course there are many problems in implementing it.

If we are to harness this solar energy, I doubt it would be free. First of all if it is done on arable land and precludes growing food, it is nothing but another tradeoff. But there is plenty of desert on this planet so that issue can be disregarded for now and we must move on to the real issue. Storing and trasnsporting the energy.

See people don't live in the desert, that is a desert by definition. So how do we get that energy to where it is to be used ? There are several ways, the problem is that none of them are all that efficient right now. Even the collection system is an engineering challenge. That is at least surmountable, they know what latitude it will be at and design accordingly, these things are not going to be portable. But what do we want out of them, steam, or heat by some other medium, or electricity ?

You know it could be both. Ovonic type solar cells, along with others basically use only a small part of the spectrum, thus a dichroic type coating could be applied and it could generate both. However with the inefficiency of today's solar cells the best I would hope for is that the facility could generate enough electricity to sustain itself, and go on to produce heat. But then the heat is most likely to be turned into steam and used to generate electricity anyway, so what's the use ?

However I do believe that using natural resources is the key to this problem. This can encompass many things. We are talking solar thusfar, but what about wind ?

For example you could have wind powered pumps that pump seawater into tanks up high, then the water pushed by it's own weight is a form of energy. I read somewhere that someone actually harnessed the tides of the ocean not too long ago. Never heard anything more about that.

Maybe what we need to do is back up, at the moment we are thinking backwards, which works sometimes. But not here apparently. Maybe we need to go way back and think forward from there.

The pyramids are nice, but they are pieces of shit. There is an ancient building on the American continent somewhere that functions as a clock and calendar, using the incident angle of the sun's rays. If they could build that, putting up a bunch of mirrors should be a simple task for us. It's just that all of the currently available technologies with which to store and transport the energy are hopelessly inefficient.

And anything right now that will make anything move, like to turn a turbine or whatever, will require water. I've heard that some deserts don't have all that much water :-)

The realist can see why these things are not implemented now, and I will say that money is one of the reasons. But if the money people were reasonable people, which they are not by any stretch, EVEN IF THEY WERE it would be unreasonable for us to have them go whole hog into this today. If I had forty million in the bank I would gladly put up say half of it. But all of it ? No.

Actually the people who really do figure this out will probably do well.

I'll tell you what big money does not want to see, is self sufficiency. This can be done now, but the cost is very high. You could have an electric car, all electric home except heat, partly geothermal and partly an adaptive heating system. You could have a well for water and a septic tank and your gutters collect rainwater, up high, and that stored kinetic energy is used to power your cellphone chargers and your uplink or whatever for the internet.

I know science and I know and see the analogies throughout. How hydraulics is so similar to electronics, take the case of an automatic transmission, an old one without computer control. The valve body is a circuit board. The circuit created is technically an analog computer. How does this apply ?

Because perhaps we need to do a little math. Would it be more efficient to pump water up to a high tank and use the flow to serve our needs on demand, would be more efficient than batteries for example ?

Y'know they say necessity is the mother of invention, well I have something to add.

Simplicity is the mother of success.

See where I am going. Get out of all these exotic materials and who the fuck knows. Get into the forces of nature, make gravity your friend because he ain't going anywhere anytime soon.

See whadd I mean ?

When you know science of course you get ideas, but usually they are shot down before they are ever expressed. Can't do this because of that, can't do that because of this, and so forth. Indeed who would attempt something they knew would fail ?

But there are times when 'out of the mouths of babes' come answers. At any time someone could pop up with an answer that even seems assinine on it's face, but when considered carefully might just work. It would not be the first time in history you know.

Maybe part of what I am saying is that ,,,,,,,,,,,, you could be hitting this from two different angles -

Economical/sociopolitical - Gas is ridiculous, and it's even worse in Europe I guess. We live in what I now dub "The Oil Age". Just like the stone age and the iron age, it will run it's course.

Ecological - If you want to save the planet, you must work with the planet. Like a friend who needs help, they must participate. Yes ask what you can do for your planet, but also ask what your planet can do for you. She has gravity, geothermal heat all stored up and gets something like 1/138,000th of the sun's energy. And the sun can be a very big friend indeed.

I preface this now for the benefit of someone who said something ; I mean no romantic intent. But I will say this, the answers for the future might actually be found in the past.

T

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RE: Alternative Fuels Roundtable - 4/20/2008 9:13:27 AM   
TheHeretic


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quote:

ORIGINAL: slaveboyforyou



No it's not a crock because it doesn't work.  It's a crock because it's not green.  It uses up valuable agricultural land for energy production.  We only have so much land that is suitable for food production.  It also takes more energy to produce biodiesal than it's worth.  Most of our energy comes from coal.  So in producing biodiesel, we cause more pollutants to spew into the atmosphere. 




          The question of land use is going to depend heavily on what sort of crop we are squeezing the oil out of.  Corn is an awful option.  I'll even agree with Sugar about the influence of agri-business on the push for ethanol (agreeing with the fact of it, not the socialist/communist spin on how to fix it).  If we go with microalgae, that can be grown in all sorts of places that wouldn't compete for land with conventional food crops.

         I'm not sure where you got the idea that it takes massive amounts of energy to produce biodiesel.  Sunlight (direct or channeled) grows it, and if we built engines to the fuel, the product could go directly from the press to the pump.

          Bicycle tunnels/lanes?  Maybe for some limited individual transport applications in densely populated areas, but as any kind of solution, useless.  Try bringing home a week worth of groceries, much less a few sheets of plywood.  Whatever we go with will have to fit our lifestyle, not the other way around.  

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RE: Alternative Fuels Roundtable - 4/20/2008 9:30:21 AM   
Padriag


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quote:

ORIGINAL: Termyn8or

I'll tell you what big money does not want to see, is self sufficiency. This can be done now, but the cost is very high. You could have an electric car, all electric home except heat, partly geothermal and partly an adaptive heating system. You could have a well for water and a septic tank and your gutters collect rainwater, up high, and that stored kinetic energy is used to power your cellphone chargers and your uplink or whatever for the internet.

Depends on which "big money" you mean...  Its true that oil companies and electric companies don't want to see energy independent homes.  Its also true that solar cell manufacturers, building contractors, and realtors do want to see them.  Not to mention home buyers.  There's big money on all sides.

And you could have a fully electric home, including heat either in the form of baseboard (which is much loathed because of the power consumption, but if you've got plenty of solar power available... not so much of a problem anymore) or heat pumps with high efficiency electric furnaces (a better choice but sometimes harder to retrofit into older homes).

If we get next generation solar cells with an efficiency around 38%, we're getting in good shape to make all of the above possible.  Right now the best you can get on a home with solar panels is about 8Kw per hour with the average running closer to 4-6Kw depending on geographic location.  Next generation solar cells could triple those numbers... meaning 12Kw to 18Kw per hour for an average home... more than enough to run your lights, appliances, electric heat, and still have enough left over to charge your electric car.  Which will just leave the problem of cost installation.  Frankly, rising fuel prices may well solve that for us.  Part of the reason things still cost so much is the limited market.  A company making solar cells has to pay employees, pay for materials and turn a profit... the less product it sells the more it has to charge to cover all its costs.  However, if demand increases because of fuel costs, then said company can charge less per unit (to a point) and still cover its costs.  That makes it possible for costs to drop.  What will actually drive it down at that point is market competition, multiple companies manufacturing similar products and thus competing for the same business.  Which means part of what we need to be doing know is encouraging more manufacturing diversity.

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RE: Alternative Fuels Roundtable - 4/20/2008 9:35:47 AM   
Padriag


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quote:

ORIGINAL: TheHeretic

         The question of land use is going to depend heavily on what sort of crop we are squeezing the oil out of.  Corn is an awful option.  I'll even agree with Sugar about the influence of agri-business on the push for ethanol (agreeing with the fact of it, not the socialist/communist spin on how to fix it).  If we go with microalgae, that can be grown in all sorts of places that wouldn't compete for land with conventional food crops.

I spoke recently with a local engineer about microalgae.  What he proposed were green houses used to grow the stuff with the resulting bio-diesel being used to run a power plant.  According to his concept, the exhaust from the plant could be run back through the greenhouses to reduce the carbon emissions... essentially creating a power plant with a low or near zero carbon footprint.  I'm still waiting to see specifics of how it would work and indicitions it would actually be practical.  I liked the idea of it though and told him if he could put it together, I'd build the damn thing.

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RE: Alternative Fuels Roundtable - 4/20/2008 2:02:23 PM   
slaveboyforyou


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quote:

I'm not sure where you got the idea that it takes massive amounts of energy to produce biodiesel.  Sunlight (direct or channeled) grows it, and if we built engines to the fuel, the product could go directly from the press to the pump.


There are several sources out that support my claim.  Here's one:

http://www.sciencedaily.com/releases/2005/07/050705231841.htm

quote:

ScienceDaily (Jul. 6, 2005) — ITHACA, N.Y. -- Turning plants such as corn, soybeans and sunflowers into fuel uses much more energy than the resulting ethanol or biodiesel generates, according to a new Cornell University and University of California-Berkeley study.

"The United State desperately needs a liquid fuel replacement for oil in the near future," says Pimentel, "but producing ethanol or biodiesel from plant biomass is going down the wrong road, because you use more energy to produce these fuels than you get out from the combustion of these products."








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RE: Alternative Fuels Roundtable - 4/20/2008 2:22:41 PM   
Hippiekinkster


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Heretic:"Bicycle tunnels/lanes?  Maybe for some limited individual transport applications in densely populated areas, but as any kind of solution, useless.  Try bringing home a week worth of groceries, much less a few sheets of plywood.  Whatever we go with will have to fit our lifestyle, not the other way around."

Well, they have tunnels at busy urban intersections all over Europe. I said nothing about them being exclusively for bicycles, did I? For that matter, there are bicycle lanes on the sidewalks all over Europe, too. No big deal. Bicycles are perfect for short commutes. They also make these things called saddlebags which hold things, too. Like groceries.

Can't never could.

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RE: Alternative Fuels Roundtable - 4/20/2008 2:46:44 PM   
bipolarber


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Hummm... it only takes $40,000 to become energy independant of the grid? Not bad, really... I wonder how effective it would be to put enough solar panels up on my home to just run my central AC? That's really the energy hog during the summer. If I could do THAT alone, for about the cost of a new car, it would pay for itself in less than ten years. No need for batteries, I'm just thinking supplamental energy during the brightest, hottest parts of the day... and if thousands of homes did the same thing, there wouldn't be such a huge pull on the grid. No more brown outs....

Solar cells need to get 50% efficient? Or just 50% cheaper? As I understand it, new photovoltaic roofing materials are now hitting the market. (I toured a prototype home using pV shingles last year... that home needs to only hook up to the grid about two weeks a year, when we have a long string of dark, gloomy days.) I think the days of "green" solar housing are just getting started.

And I believe this discussion is relevant tot he OP's post... electric cars that you plug in between trips are another viable solution. Too bad CA caved on the zero emissions legislation, and GM scrapped all the electric cars. The program was becoming too popular, apparently, for the oil companies to take lying down...

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RE: Alternative Fuels Roundtable - 4/20/2008 2:58:33 PM   
Hippiekinkster


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quote:

ORIGINAL: bipolarber

Hummm... it only takes $40,000 to become energy independant of the grid? Not bad, really... I wonder how effective it would be to put enough solar panels up on my home to just run my central AC? That's really the energy hog during the summer. If I could do THAT alone, for about the cost of a new car, it would pay for itself in less than ten years. No need for batteries, I'm just thinking supplamental energy during the brightest, hottest parts of the day... and if thousands of homes did the same thing, there wouldn't be such a huge pull on the grid. No more brown outs....

Solar cells need to get 50% efficient? Or just 50% cheaper? As I understand it, new photovoltaic roofing materials are now hitting the market. (I toured a prototype home using pV shingles last year... that home needs to only hook up to the grid about two weeks a year, when we have a long string of dark, gloomy days.) I think the days of "green" solar housing are just getting started.

And I believe this discussion is relevant tot he OP's post... electric cars that you plug in between trips are another viable solution. Too bad CA caved on the zero emissions legislation, and GM scrapped all the electric cars. The program was becoming too popular, apparently, for the oil companies to take lying down...

I wonder why all these expert types here have never heard of the solar shingles you mentioned? I've known about 'em for 3 or 4 years, and I'm just a layman.

< Message edited by Hippiekinkster -- 4/20/2008 2:59:28 PM >

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RE: Alternative Fuels Roundtable - 4/20/2008 3:48:59 PM   
shallowdeep


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quote:

ORIGINAL: Padriag
The author is selling a pipe dream... concentrated sunlight won't get you any more power on anything except a cloudy day.

Did you really read the article? It's about concentrated solar thermal, which has nothing to do with photovoltaics, and is not a pipe dream - ask the Department of Energy. It may not be as efficient as PV could be, but when dealing with a free and plentiful resource like sunlight, efficiency is secondary to cost effectiveness - and concentrated solar thermal is currently cheaper. It is, however, limited to large scale installations.

Also, the given explanation of the limits of photovoltaics is incorrect. The efficiency of a solar cell is limited by the fact that most photons don't exactly match the band gap of silicon (or other materials used). Low energy photons don't generate any current at all, and high energy ones waste excess energy as heat. It's not that photons aren't being absorbed, it's that the energy is being turned into heat rather than electricity. Efficiency can vary a little bit with irradiation levels, but the effect is generally an increased, not decreased, cell efficiency - although this may be offset by the higher temperature. Since efficiency remains (more or less) the same, more light does result in proportionally greater electrical power output. Therefore, concentration does work and actually is used with more expensive, higher efficiency cells. It's not cost effective with cheaper cells. You are correct that photovoltaics can't be used with the same large scale concentration used in solar thermal, but that's because the cell would be destroyed by the heat, not because you suddenly run out of excitable electrons, which are continuously cycled through the circuit.

quote:

ORIGINAL: Padriag
The problem is that on a massive scale (fuel cells) will require equally large amounts of fresh water on a daily basis.

Fuel cells produce water, they don't consume it. Granted, the required hydrogen has to come from somewhere - possibly electrolysis of fresh water. But, since the same amount of water split in electrolysis is produced by recombining the hydrogen with oxygen in the fuel cell, there is no need to continuously replenish it. The problem is that such a closed system is not a source of energy. Fuel cells/hydrogen have potential as an energy storage and recovery medium, not as an energy source.

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RE: Alternative Fuels Roundtable - 4/20/2008 3:51:40 PM   
QuietlySeeking


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quote:

ORIGINAL: Termyn8or
For example you could have wind powered pumps that pump seawater into tanks up high, then the water pushed by it's own weight is a form of energy.


Daytime load power is partially produced in Chattanooga, TN by a system similar to this suggestion.  There are large reserviors at the top and bottom of a mountain.  In the evening (while electric usage/rates are low), the water is pumped from the bottom to the top.  During the day, when peak usage and other demands require larger amounts of electricity, the water falls through large pipes from top to bottom, running generators.

(in reply to Termyn8or)
Profile   Post #: 58
RE: Alternative Fuels Roundtable - 4/20/2008 4:23:21 PM   
Padriag


Posts: 2633
Joined: 3/30/2005
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quote:

ORIGINAL: bipolarber

I wonder how effective it would be to put enough solar panels up on my home to just run my central AC? That's really the energy hog during the summer. If I could do THAT alone, for about the cost of a new car, it would pay for itself in less than ten years. No need for batteries, I'm just thinking supplamental energy during the brightest, hottest parts of the day... and if thousands of homes did the same thing, there wouldn't be such a huge pull on the grid. No more brown outs....

Depending on the size of the unit (heat pump) and where you live, about $10,000 could give you a good enough supply.  During months where you don't run it much, you might even be able to sell a bit back to the power grid. 

The photovoltaic shingles are not nearly as efficient as regular panels, meaning they produce a lot less energy.  But they are also cheaper.  Its funny you should mention them, I was just talking with a friend of mine (an engineer) about them.  His thoughts were that it might worthwhile to be able to sell power back to the grid during the day and buy it at night... wouldn't make a home energy independent, but it would reduce their power bill which fits with my goals for low to middle income housing and might still be within the budget for homes in that price range, its something I'm going to check into further.  Couple of drawbacks for my application are questions I still have about their durability as well as the cost to repair them.  The kind of people I sell houses too simply couldn't afford to pay a specialist to repair such a roof if a regular roofer can't do it.

_____________________________

Padriag

A stern discipline pervades all nature, which is a little cruel so that it may be very kind - Edmund Spencer

(in reply to bipolarber)
Profile   Post #: 59
RE: Alternative Fuels Roundtable - 4/20/2008 6:42:17 PM   
bipolarber


Posts: 2792
Joined: 9/25/2004
Status: offline
Well, Padriag, you can say the same for many of the alternative energies that are being discussed here. Emerging tech always has a steep learning cruve where people need to be trained for servicing it, installing it, or designing applications for it. Nothing exists in a vaccuum. There has to be support infrstructure, obviously.

So, not only will it help make us more energy efficient, whole new local industries will be born out of it. (and the smaller companies that support them.)

I imagine that back in 1902, when Henry Ford came rattling out of his garage in his horesless carriage, he could hardly have imagined where it would lead...

(in reply to Padriag)
Profile   Post #: 60
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