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Joined: Jan 2005
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Cat Servant
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Big efforts lead to big failures.

IMO, that's the problem with the 'alternative energy' crowd. Like the best of the commissars, they think in terms of massive 5-year projects covering hundreds of square miles. I guess they can't imagine anything happening without government programs / money / control.

It doesn't have to be that way ... and the proof was made right here in the USA.

Up into the 40's, many rural homes had their power supplied by small windmills. These windmills worked in slower winds, were self-feathering, and did yeoman service. When the "Rural Electrification Administration" came along, these folk were required to destroy the generators - most often by tipping them off their mounts, to crash into the ground below. There many sit, to this day.

OK, so there were very real interconnection issues. We've since solved those problems. I'd rather see every home with a quiet 1KW unit, than have to depend upon thousnads of whopper bird choppers filling the middle of Nevada.

Joined: Apr 2003
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Originally Posted by renosteinke
Big efforts lead to big failures.


…and big successes as well!


Bryan P. Holland, ECO.
Secretary - IAEI Florida Chapter
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My biggest question about what will happen if we had 20% or more of solar/wind power is what do you do when the wind isn't blowing and it is night time? You are still going to need as much traditional generating power as we have now but it will have to sit idle while the "free" stuff is working but be ready to fire up at a moment's notice when a big cloud comes over or when the wind dies down. That is going to be an expensive plant to maintain and not as much revenue to maintain it. The thing that sets the US apart from the 3d world is the reliability of our power infrastructure and I think that will go away.

I really believe when they feathered the windmill in Minot it was to deal with a drop in demand.


Greg Fretwell
Joined: Dec 2001
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Feathering is indeed used for demand control.

Typically this is also the first thing they do upon an increase of wind speed. Then they rotate the entire head of the mill out of the wind, and if nothing else works there is a mechanical brake working on the transmission. I have no idea how this could have happened and never read an actual explanation, only general alternative energy sources bashing.

The more realistic supporters of renewable energy always underline it is important to spread power generation over several different sources and large areas to level out wind, sun,... influences. Another method is to use any excess power generated to piower pumping power stations that will in turn produce power in low wind times/ at night. A healthy mix is the key to success and a stable power supply!

Quote
The thing that sets the US apart from the 3d world is the reliability of our power infrastructure and I think that will go away.


It already seems to have dropped considerably with decades of low maintenance and decrease of generating capacity after deregulation. Failure is not inherent of certain systems, it's caused by bad judgement.

Joined: Mar 2005
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Originally Posted by gfretwell
My biggest question about what will happen if we had 20% or more of solar/wind power is what do you do when the wind isn't blowing and it is night time? You are still going to need as much traditional generating power as we have now but it will have to sit idle while the "free" stuff is working but be ready to fire up at a moment's notice when a big cloud comes over or when the wind dies down. That is going to be an expensive plant to maintain and not as much revenue to maintain it. The thing that sets the US apart from the 3d world is the reliability of our power infrastructure and I think that will go away.

I really believe when they feathered the windmill in Minot it was to deal with a drop in demand.
The economics are key. Honestly, if our wind and solar resources are spread out, there is very little chance we will lose *all* our wind and solar simultanously. And certainly not very quickly, at least outside of a solar eclispe, and even then, the total occlusion is usually limited to a small area and certainly predictible.

But we still need extra plant capacity, and that's highly expensive infrastructure, just sitting there wasted and unused. Pocos make more money running at 100% with 1% rolling brownouts than that do at 99%; it's like the airlines with that respect; no incentive to add planes or plants if they're not going to be utilized eto 100%. So, we end up with a situatiotn like Texas where the only other source of power were emergency stand-by generators that people have to invest in anyhow.

...which, actually, has never been brought up in a solar/wind debate that I'm aware of, but IS a great untapped source of power generation- there's no spool-up time required like there is to build up pressure at a steam turbine plant, 10 seconds after the brownout hits the preset on the ATS, that plant is up on generator. If 20% of the US has their own generators and has to run them 1 day a year because of a freak mass solar/wind outage, that's OK. The pocos give them a price break for doing something they'd do anyhow (go to generator during a brownout), coal and gas consumption is reduced considerably from all the "free" energy, and everyone wins.

Still, anyone who thinks wind and solar can become more than a niche in american power is dreaming. What we reallly need are more nuclear plants.

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Originally Posted by gfretwell
My biggest question about what will happen if we had 20% or more of solar/wind power is what do you do when the wind isn't blowing and it is night time? You are still going to need as much traditional generating power as we have now but it will have to sit idle while the "free" stuff is working but be ready to fire up at a moment's notice when a big cloud comes over or when the wind dies down.


That is the sad truth about alternative energy. They all have their limitation. Currnetly at best with the national grid system (despite it's current condition), alternative energy systems only supplement the grid. It helps but does not fix the proplem. Solar does work on cloudy days but not as good on a sunny day. Currently the best all around alternative energy source is is hydro it the areas can support it since it can be operated 24/7, in the dark and with no wind. There are limitations as well. Althouygh they can pay for themselves, they are very expensive and a pistol to get built. He in Southeast Alaska, Most people get their power from hydro. The problem is most of SE Alaska is protected by environmentalists. Currently two of our largest communites are up against the wall because their generation capacity has been outpaced by growth. To add to the problem, fuel cost has sky rocketed. This pushed utility rates and construction. The hydro system I am on has an abundent surplus of power. everyone wants to tap into it but it cost miillons of dollars and lines need to cross disputed and protected lands. With todays fuel costs, more and more people here are going to electric heat. The reservoirs are slowly dropping already. Although we have the capcacity now, the suplus will keep getting chipped away where we will be in the same boat eventually. The only upside is anyone who taps into our system can be cut off if the demand exceeds the capacity.

Now that I am on a roll and off the topic of the original post (sorry), here is some food for thought. Our planet recieves 5000 times more energy from the sun then we use daily. I ran some numbers. In theory if each person on the planet had a solar array that is 125 square foot array or ten, 125 watt panels per person and they were all interconnected around the world, we would be able to shut off every single power plant in the world and be powered by totally by the sun.


"Live Awesome!" - Kevin Carosa
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You still have the problem of "night" with the solar plant. In the winter that is a significant part of the 24 hour cycle and also when there is considerable demand. The wind might be blowing or it might not. That means you need some traditional capacity to handle the load but that will be sitting idle when it is not needed. It is hard to amortize that investment if it is idle most of the time (the goal).

The idea that you are going to supplement this with home generators is simply ridiculous, from an economic or pollution standpoint. The most expensive power anyone has ever used came from a small genset. These small engines are also massive polluters. I know people who lived off their generators for extended periods after hurricanes and they call it "feeding the monster". A generator might be handy for a short (day or two) outage once or twice a year but if you are using it much more than that fuel costs and maintenance will easily double or triple your energy bill. Honda and Generac can never compete with FPL.


Greg Fretwell
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You telling me the panels will not work at night? What if I used a flash light I plugged into the array before sunset? smile

My message was a little long. I mentioned that that 6 billion mini arrays were tied together around the world. In every back yard from the north to the south and in each and every time zone. It is a pipe dream but is is not all that unrealistic. the panels that are manufactured today are around 20% efficient. Just a few months ago, some lab sucessfully tested a cell that was 40% efficient. Although it will be a few years before you see it on the market but that would reduce the array down to 75 square feet or 5 panels the size of todays 125 watt panels per person on the planet.

They can all be tied in the existing grids and the grids around the world can be tide together with up and coming super conductors. The voltages and the freqs can be converted as needed.

Its doable when the technology becomes a reality. It doesn't hurt to dream. High temeperture superconductors are currently are being used in Detroit Michigan, Aurbany New York, and Copenhagen Denmark. They apparently working pretty good. as the cost comes down, It can become more viable. There is a few logistical (global) matters workout. Remote and desert areas can house large arrays instead instead in the pole regions (wind turbines or hydro) and Europe would have sort of have a problem at night since the sun is over the Pacific then.

All it would take is everyone in the world to work together, trillions of dollars for developement, trillion of more dollars to build it. Think about it.


"Live Awesome!" - Kevin Carosa
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Originally Posted by sparkyinak
That is the sad truth about alternative energy. They all have their limitation. Currnetly at best with the national grid system (despite it's current condition), alternative energy systems only supplement the grid. It helps but does not fix the proplem. Solar does work on cloudy days but not as good on a sunny day.
I agree completely. Though I disagree with your calculations. Though "in theory" each person might not need much, westerners use a disproportionately large amount of energy. In the north, demand goes up in the winter right when solar flux is dropping and solar panel efficiency is dropping from thermal derating and snow cover. So, unless you can pump that energy up from the southern hemisphere, you'd need something like 12,000 square feet per person. (That's just a stab; I worked it out once a while back, but don't recall the numbers offhand.)

Not to mention night wink
Originally Posted by gfretwell
You still have the problem of "night" with the solar plant. In the winter that is a significant part of the 24 hour cycle and also when there is considerable demand. The wind might be blowing or it might not. That means you need some traditional capacity to handle the load but that will be sitting idle when it is not needed. It is hard to amortize that investment if it is idle most of the time (the goal).

The idea that you are going to supplement this with home generators is simply ridiculous, from an economic or pollution standpoint. The most expensive power anyone has ever used came from a small genset. These small engines are also massive polluters. I know people who lived off their generators for extended periods after hurricanes and they call it "feeding the monster". A generator might be handy for a short (day or two) outage once or twice a year but if you are using it much more than that fuel costs and maintenance will easily double or triple your energy bill. Honda and Generac can never compete with FPL.
Energy demand is still much higher in the day than at night, hence why energy is so much cheaper at night. Solar fits the bill very well with this respect, as it's peak production coincides with peak demand, and as it's only constituting a small % of the total power generation compared to normal day/night fluctuations in demand, its loss at night is not presently missed.

And I was not suggesting we use portable generators to supplement solar in any practical way. But if we use 20% solar and wind, it will frequently drop to maybe 10%, in which case a few gas-fired plants may be economicical, even if they're only running 25% of the time. But the chances of this 20% dropping to 2% or 0% are so small and so seldom, that pocos would rather see rolling blackouts than build those plants.

So, what I meant was that while amoritization of idle plants makes them impossible, we do have a huge number of stand-by plants sitting around. I'm not talking 3500W gas burners in a garage, I'm talking 3MW or 500kW energy efficienct diesels sitting in industrial parks. Amortization is irrelevant; they're required anyhow. These big gens pick up the slack, and joe homeowner is still fat dumb and happy on the remaining 80% of utility power. Fuel cost is about twice that of coal for a diesel gen, but cheaper than building a new power plant. CO2 emissions are slightly less than coal. Efficiency is somewhat lower than that of more massive plants, but it's not all THAT much lower, it's on the order of single digit percentages. And would only be running in that 0.0001% (or whatever) chance we simultanously lose all solar and wind power across north america.

Now, jack that 20% up to 80% like some environmentalists think is feasible and throw all this out the window!

FYI, fuel costs for a 500kW diesel generator run about $0.21/kWh (at $3/gallon) and all the other costs (including maintenance) are already a wash because they'd be required anyhow. You might see a small bit of increased maint if it runs a lot, but 24 hours per year for something like this would be insignificant to a typical stand-by generator.

Joined: Jul 2002
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solar includes wind and neither are viable without a storage solution. Using the energy produced to make hydrogen gas might work in the future. New batteries are making headway. Conservation is the biggest gain we could make at this moment. No one wants to hear that.

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