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The bad news about windfarms.... 14

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I didn;t see anything about cost. I'm wondering if the cost falls with efficiency. At least the maintenance cost should fall with efficiency. The real beauty of an offshore turbine is that if the thing falls over in the water. It will immediately sink to the bottom of the ocean and at 2mw, no one will ever miss it and it won't cause an environmentat disaster.

Neil
 
I would think that cost of equipment is like most things and probably increases with higher efficiency. Maintenance probably goes up with that, given increased efficiency is often accompanied by higher complexity, but according to the typical definition of higher efficiency either power consumption would drop for a given amount of work output, or power gen would be higher for a given work input, thereby making for a cheaper overall lifecycle operation cost, and hopefully reducing payback time to make the higher initial cost of that higher efficiency more attractive in the long run. Lower costs are often simply an unsustainable result of temporarily increased competition factors, rather than improvements in the manufacturering proceedure itself.

It simply follows the old addage, "there is no free lunch." Higher efficiency costs more, but reduces the operation cost, thereby making it a better investment over time. If it doesn't work out that way, then don't look for the technology to be adopted on its own merrits alone. It will need tax credits or some other investment incentive to make it happen. While it may be poor economics for it to work out in the short term by financing these things with tax credits, etc., everyone hopes that the cost of providing whatever investment incentive today will be temporary while it fosters the development and mass acceptance of the technology to the point where continued use past a certain break even point (including the investment incentive cost) is passed some day and they become cheaper in the long run. It does seem like a bit of a gamble from time to time, but "we must have faith", right? In the meantime I just wish it didn't seem like its being given such a massive push that it will only result in benefits for the tax credit buyers and that the leap of faith it is taking all the rest of us will be forgotten in that same long run that it will take to get there.

Let your acquaintances be many, but your advisors one in a thousand’ ... Book of Ecclesiasticus
 
Assuming that increased efficiency goes hand in hand with increased cost is an appropriate assumption for established technologies (such as a pump). But not for electrical components, complexity of a CPU has increased greatly but cost to the consumer has remained fairly constant.
Photovoltaics may follow a path similar to that of computers. It is still in its infancy with unexpected advancements happening all the time. Such as the addition of a genetically modified virus boosting efficiency at MIT.
(published in Nature Or possible radical changes to the way photo-voltaic cells are structured, such as those recently put forward by Oak Ridge National Laboratory. (Seeing these I remain hopeful that my 15.00 USD/yr (2009 IRS tax data)(doesn't seem like such a burden now does it?) I contribute to those tax incentives and research for renewable technology will help create a viable supplemental energy sources that can thrive on their own economic merit in the future.

Comprehension is not understanding. Understanding is not wisdom. And it is wisdom that gives us the ability to apply what we know, to our real world situations
 
Good point. The roughly constant price for increased efficiency is undoubtedly the main reason that computer technologies have been so rapidly and widely accepted in society, as could also result even if simulation on an expensive computer was still worth the knowledge gained, might be in simulating nuclear explosions, etc. In any case, you say PV "may" be one of those, and as we are apparently still in the "waiting period" to see if this applies to PV and other renewable energy technologies, it would indicate that the effect still has not been reached. Hopefully, if not now, it soon will be.

Let your acquaintances be many, but your advisors one in a thousand’ ... Book of Ecclesiasticus
 
Exactly how much energy is used to manufacture PV cells? Is it more or less than what you expect to recieve from the PV cells? And how should one despose of used PV cells?

These are the same issues with wind power. Does the energy from the wind exceed the energy used to build the wind machine?

If these questions can't be answered, then I suspect the answer is they require more energy to build then they ever produce, making them not a enviromential marvial, but a jobs program.
 
That question was answered many times It takes under a year to produce energy equivalent to what is consumed in the construction of the turbine. Quick google search showed numbers ranging from 3-8 months varying on size and placement.
Once you factor in standby power plants, required in some situations for low wind days, it can be much longer. I believe this was a major factor in the cancellation of a UK windfarm. The natural gas plant needed for backup actually canceled out many of the benefits touted by the proposed project.

As far as PV cells, most have a 20 year warranty, after that? They end up in a pile in China along with the rest of the worlds e-waste.

Renewables are not going to work everywhere for everyone tomorrow. It shouldn't be expected to, the first airplane flew 900ft should we not have invested in airplanes?

Comprehension is not understanding. Understanding is not wisdom. And it is wisdom that gives us the ability to apply what we know, to our real world situations
 
So are they worth the investment? So why do we still have tax breaks for them?

If the free market isen't interested, why is the goverment?
 
Not yet. Well.. actually the jury is still out and until then, you have to consider that it will be more like a publically funded research and development project. You have to decide if that's worth it as you cast your vote.

Let your acquaintances be many, but your advisors one in a thousand’ ... Book of Ecclesiasticus
 
Renewables don't make sense when competing against fossil fuels with zero charges applied for disposal of their atmospheric waste. Fossil fuels win hands down without an atmospheric tipping fee, until they're in short enough supply to drive up their price by a very large margin.

Charge for the disposal of the effluent, and suddenly the economics change- and the free market becomes interested big time.

Does government subsidy of renewables make sense in the meantime? Personally I don't think so. Subsidy is not sustainable and distorts the market, holding serious ethical investors at bay and making corruption more likely. Why would you put your money into an industry which goes broke the minute a government subsidy goes away?

No different than the situation I was in when doing renovations on my home. If I was permitted to just throw all the demo debris on my neighbour's yard or in the city park, why would I pay for a bin to dispose of the debris, much less cut all the wood up and burn it in my woodstove? What's the payback for my effort? It's the problem of the commons: we all bear the costs of atmospheric pollution and adaptation to climate change, yet there is no feedback of this cost to the consumers of fossil fuels to deter their consumption. It's a formula that leads to overconsumption.
 
Make me go back to the cost of thermal polution caused by PV panels, vs the reflection of the unused sun light back into space. There hasen't been assigned a cost to that global warming issue.

At least wind reduces something most of us don't need. But what will happen to all those towers when the wind machines have failed?
 
Stork nests

Let your acquaintances be many, but your advisors one in a thousand’ ... Book of Ecclesiasticus
 
As far as PV cells, most have a 20 year warranty, after that? They end up in a pile in China along with the rest of the worlds e-waste.
Click to expand...

Who would throw away a panel just because its warranty expired? Those early adopters are still getting power today. There are some panels out there, over 40 years old, still cranking it out.



Sandia Labs tests find only a 0.4% decrease in peak power per year of use (King, Quintana, et.al., 2000).

Solar panels haven't been readily available for long enough to prove to the general public that they last for a very long time, but to the scientific crowd that started studying them early on, and for those few that chose to use them long ago, there is no doubt.

I thought this thread was supposed to be about wind farms?

Now if you want to critique wind power on longevity grounds, then you got me there. The rows of derelicts in California's Tehachapi pass were a testament to that (gradually being replaced by now I hope?).

Steven Fahey, CET
 
I think the criticism voiced on PV output depletion is valid when considered as a commercial enterprize, where you actually have to put out some cash to keep the system alive. Cleaning, the inverters (an expensive part of the balance of system) still burn out every so often as well and there is the occasional replacement to gopher eaten cables, etc. If its a hobby rooftop installation, you can get away with no cash outlay for those kind of things, but they will eventually eat you alive when your commercial PV installation output drops to 60% and you've got 20 acres of the stuff out there to clean and maintain.

Ya, sometimes the thread content rules get bent a bit... just to keep the thread fresh. Somebody should close it some day too.

Let your acquaintances be many, but your advisors one in a thousand’ ... Book of Ecclesiasticus
 
So will there become a market for used PV? (Sort of like used cars).

If so, can we purchase them for a car port roof?
 
I think that there already is a VERY BIG market for used PV panels. It seems that the problem there is that they are usually snapped up before they make it to Ebay. You very seldom see any panels advertised anywhere. I'm sure very few of them are actually going in the bin.

Let your acquaintances be many, but your advisors one in a thousand’ ... Book of Ecclesiasticus
 
I got a call after I was l laid off about working in the alternative energy industry. The caller, a state government worker, asked if I was qualified. I answered in the affirmative. They asked a bunch of personal questions but never one about my education or experience. They asked if I had kids. I answered in the negative and asked why they would ask. People with children were subsidized by the federal government so they counted. People like me didn't. It's one more subsidy to make me dislike alternative energy.

Is that discrimination by government? Yes.

I've seen countless wind farms that are in some state of not operating in spite of winds. I've driven by the wind research center in CO many times. I've yet to see any of them working. The last time I paid attention some were in bad need of repair.

It takes a lot of energy to make flat glass in large quantities for PV.
 
Btw, China installed more wind power last year than North America and Europe combined:

Not too long ago wind farms in Texas prevented a rolling black-out:
Last March Spain wind power produced 21% of Spain's electricity: Spanish wind power is not only effective in reducing gas but also water consumption: Spanish demand curve (including varying demand and variable but predictable renewable sources):

The capacity factor is not just a question of location but also a question of the wind turbine: A large rotor with a small generator yields a higher capacity factor.
Meanwhile Vestas, RE-Power, Enercon, Gamesa etc. have turbines specifically designed for low wind regions.

Fossil fuels and nuclear receive more subsidies than wind power and have received them for a much longer time period:
Thinfilm PV-modules can meanwhile be purchased for less than a $1 per W:
And PV-Inverters can be found for $0.3 per W.
You can essentially build a PV system for less than $2 /W. At a capacity factor of only 15% and 25 years life time you are at $0.06 per kWh (not counting interest and maintenance costs but keep in mind: There are no moving parts).
(A new nuclear power plant is around $7 /W requires cooling water, uranium imports, long construction time, repository etc. and needs to compete at wholesale electricity prices: A modern thinfilm module can produce 30 times more energy than is needed for its production.
Of course cheaper than any new power plant is investing in efficient appliances. Most people are unaware what efficient appliances can save.

And if you are worried about the thermal pollution of a black surface: Compare the PV-surface area with the asphalt surface area.

And if you are worried about the scrap metal coming from a wind turbine: Compare it to the scrap metal coming from cars, trucks, ships, locomotives, aircrafts...
 
I am a sceptic mainly because very few people are willing to state facts. You state a few, which is a start.

A fact we can also agree to is that solar power is unavailable at about the same time every day. So it's impact can only be limited by the energy storage capacity of the system it is attached to (storage includes fossel fuels).

Wind is not blowing 100% of the time, and again it's impact can only be limited by the energy storage.

Yes solar black surfaces can add to global warming, only if it is applied in some places. If you were to apply solar panels over asphult parking lots, then we can truly say they reduce global warming. But if you place them in a light colored area, then you can't.

Wind turban blades probally don't have much metal, if they did they would be to heavy. The mass of metal in a wind machine is in the tower. And is there a scrap value that exceeds the cost of removal, safely?

Energy efficent appliances don't seem to appeal to most consumers. They aren't cheep, and don't have ice makers, with water in the door. The two major types of consumers, want either cheep, or many features, and energy efficent models don't have either.
 
Actually, most people are not willing to simply read facts (which can easily be found).

The point is: Asphalt doesn't add to global warming - greenhouse gas emissions do (besides PV as opposed to asphalt produces electric power and thus cannot heat as much as asphalt can - 1st law.) Two thirds of all fossil primary energy consumption is pumped directly into the atmosphere as heat and no-one claims that this adds to global warming in any significance either.

The fact that PV only produces power during day time is actually an advantage because there is always more power needed during day time. PV reduces the load on the grid.

Besides that interconnected wind farms provide baseload:
The US has currently 314 GW of coal, 401 GW of hydro and 79 GW of hydro capacity:
So, wind power mainly reduces fossil fuel and shifts water consumption - there's no need for any back-up:

Most mass of a wind turbine is actually in the tower. The rotor blades are relatively light and the copper in the nacelle has a significant scrap value - particularly in 25 years from now.
The reason why wind turbine blades are not made out of metal (as opposed to aircraft-wings) is because they deal with a much higher degree of varying loads.

Energy efficient lights and appliances have a return on investment of up to 40%:
( Most people simply don't think about paying electricity bills when they purchase a new appliance. )

Cheap fossil fuels will not last forever. Engineers and not bankers can develop renewable and efficiency measures to mitigate this dependence (and get paid for this work).
Engineers who fight efficiency and renewables with false pretenses cut off the branch their sitting on.
 
One factor commonly neglected in reviewing these alternative energies is the opportunity cost to the individual of these investments. Renewables are not a win-win. Yes it sounds great that a PV system over its life will have a return on investment of 3:1. How long is that lifespan? 30 years? Assume initial investment is 10,000$ The return on a U.S. treasury bond over that same period is currently 45,000$. So assuming zero maintenance on PV (unrealistic) this is still a poor investment as you are losing at least 15,000$ that could be made in other ventures. Like it or not bankers play a role, and while renewables have a promising future they are not a cure all solution, yet.

Comprehension is not understanding. Understanding is not wisdom. And it is wisdom that gives us the ability to apply what we know, to our real world situations
 
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