Use pumped storage systems to store solar genetarted electricity.

[kevarc]

"Your garden variety pole mounted transformer blowing is only a blip on the big scheme of things. Everybody arriving home from work and firing up the AC at about the same time is a bigger issue."

Not really. Now, if you cascade the tranformer failures AND have the entire town turn on their AC, then you may have a problem. A good system op knows the load characteristics and is able to ramp a unit up or down and stay with the load curve.

You can always tell if we get afternoon rain here in the summer. The load drops rather quickly, the ops need to be on their toes..

[tree68]

QUOTE: Originally posted by chad thomas

Interesting. I figured there was some control downstream from the actual generator for control. So what happens if all of the sudden a large portion of your load drops out, like a blown transformer ( I realize this is probably not that common).

Do some research on the causes of the last big northeast blackout. Should answer your question.

Your garden variety pole mounted transformer blowing is only a blip on the big scheme of things. Everybody arriving home from work and firing up the AC at about the same time is a bigger issue.

[kevarc]

Well, remember New York? That is a drastic case but it does happen. But the load will flow and their are safegrauds that are built into the system and should be used, not bypassed. If we shed load all of a sudden, we just give free juice to the grid until we ramp the unit(s) down.

Nope it is all done at the plant - the plant people do not control this, most of the time, the control center for the company/control area/region are the ones that actually control the unit. For us, our control center is her in Lafayette, LA. The units we use for load control are either in Houma, Plaquemine, or Morgan City , LA. We generelly only have one running. Now if we need to ramp the unit up, the operator in the control center here in Lafayette send a signal to the unit to increase output. The operator at the plant does not do it, unless communication is lost between the control room computer and the unit controls.

[chad thomas]

Interesting. I figured there was some controll downstream from the actual generator for controll. So what happens if all of the sudden a large portion of your load drops out, like a blown transformer ( I realize this is probably not that common).

[kevarc]

You shouldn't load controlwith a baseload plant. Coal fired plants are a total pain to ramp up and down, nucs are a bit easier.

Coal fired plant you would reduce the coal sent to the firebox, or choke back the steam going to the turbine. With a nuc you would insert the control rods to limit the reaction.

But you really do not want to, baseload plants are the cheapest to operate, so you want to run them as much as possible. For our plant we run it as high as we can and use one of our gas fired boilers to load control, they are a lot easier to ramp up and down to follow the load. Gas turbines are the easiest to follow load with and with the newer ones, they have a great heat rates. Heat rate is the total amount of heat input into a steam generator, divided by the net output of the plant in terms of kilowatts. The lower the number the better the plant. You can take that number and reference that againt the price of the fuel. That will give you a better idea on what you want. The high NG prices lately have put a real hurt on those with NG fired turbines. High furl costs can negate the better heat rate. If we still had 2.50-3.00$/mmbtu gas, they are cost comparitive with other units.

[chad thomas]

kevarc,
Could you tell me how the load is regulated at a baseload plant. I mean like when the load is less than the supply.

[kevarc]

They were clueless back in the late 70's also.

I was in college when the UMWA went out on strike. I was a member back then as that was where I worked in th summer and during holidays to pay for college. The nutters were going to have a rally in support of the striking miners. Another guy and I were having some liquid refreshments and after a few we decided since we were union folks we would go. We never laughed so hard. These folks did not have a clue. Jeez, they still had us mining with pick and shovel. When we told what is was really like in the mines they really didn't want to believe us. They couldn't understand that if we thought we needed a repirator, all we had to do was ask for one and they would give it to us. They also thought that we made 4 bucks/hour. When we told them, that as general inside laborers we were almost making 10/ hour they definately thought we were not being quite truthfull. Thankfully we had a union cards with us. We offered to go get a copy of the bargaining agreement to prove that we made what we did.

[chad thomas]

I agree there is no pleasing those idiots. And yet most all of them tree huggers live in wooden homes and drive petro-fuel burning cars. Those people are usualy the most clueless.

[Anonymous]

Wind power huh? Where I am, these windfarms have just been approved to be built. These environmentalists have been begging the state to put them up. Well, the state approved them last week, and now they very same environmentalists who were begging for them are now saying that putting up windfarms will do more harm than good; to birds and bats. THERE IS NO PLEASING THOSE IDIOTS!!!!!!!!!!!!!!!!!!!! And the EPA is agreeing with them. It's like I have been saying, no matter what you tell the EPA, they will always side with the extremest environmental groups. Sad but true. And I agree with the fact that had we signed the kyoto agreement, we would be hurting horribly economically, jobs would be goin overseas like there was no tomorrow.

[selector]

Rule # 1 in physics ; Conservaton of energy. If you extract or modify energy, there will be a systematic countering effect somewhere else. Wind turbines? Great idea until you consider what extracting kinetic energy from the atmosphere in large quantities will do. I think there are no simple answers to energy problems in a burgeoning world populaton that needs increasing amounts of energy to maintain our rates of replicating.

Interesting topic, although some seem to have short fuses.

[Anonymous]

Well... I believe that clean sources of engery will pay for themselves overtime.
They may be expensive now but who knows what the cost of Coal and Oil will be. Theee are many mounatain top sthat being blow off right now to extract coal. By using wind and solar which cost nothing in having to buy raw materials they can pay for themselves over 30 years. Coal mines could also be used as resurvoirs as recalmation.
Is it any wonder that the US has the second (Canada) in next to last of miles electrified of Railroads inthe world. Acring to my freinds at Collinwood they use 40,000,000 gallons of diesal a year between Albany and Cleveland

[kevarc]

piouslion - yep. Gotta keep the baseload unit running at as high utilization as possible. That is what they are designed for.

But that would mean that we would have clean power 24 hours a day. If we had signed the Kyoto Agreement we would be working on this right now.

First - you truely are an idiot..
Second - you think jobs are moving overseas now? Just imagine how fast the rest of our industry would move to where there will be no controls at ALL if Kyoto were adopted. Just don't spout of what you read in the papers or on the net. Read the ***ed thing and just see how bad it really is.

[Anonymous]

QUOTE: Originally posted by kevarc

Chris, at night we do pump water "uphill" back into the lakes at night, again cheaper power. They do this a lot in the west.

Dunkirk - this is the way it is - Power is a lot more expensive during the day, why would you use the expensive power to pump watrer to use at night. That is just plain dumb. You put it into the grid. Then you use cheap off-peak power to pump water uphill. That is they way it is done. Look at the price chart in the link I put in my earlier post. Solar power is not cheap, it is one the the most expensive of the renewable power sources and higher than any of teh normal power sources.

kevarc, I am a veteran of two such projects (Wallace Dam and Rocky Mountian) from my time with Georgia Power. The use of reverse pump technology has been around for a while. The use of them as has been spoken of earlier in this thread is to use electricity made at night to do the job. The main reason that the utilities do pump storage is to maintain their heat rates in their coal and nuclear units through the night. In the long run this is a great imporvement in costs of maintaining the generating grid. The longer those units remain consistant in temprature the better and less expensive they become to operate. Standard economics of the matter , the lower the cost, the greater the margin together with a stable rate per kilowatt the higher the profit to the stockholders, the greater the dependability to customers and users at a stable price.

[Anonymous]

Pump storage is an old idea whose time will only come when people are willing to have the tops of their mountains lopped off for kind of a giant toilet bowl that gets flushed every day. They tried to pu***his idea through on one of the most scenic portions of the Hudson River decades ago. It went nowhere.

Wayne

[Anonymous]

QUOTE: Originally posted by Leon Silverman

The purpose of pumped storage facilities is to maintain loading on other power plants. Unlike the relativel small prime movers used in surface transportation (cars, trains and ships), multimegawatt power plants cannot "follow the load". They can increase or decrease their output by only a couple megawatts and hour. Consequently, they have to run at essentially the same full power output all the time. The excess generating capacity is used to fill up the pumped storage reservoir at night. During the day, when these multimegawatt plants' output is insuffficient to provide all the power needs of the grid, the pumped storage water is allowed to flow back through the pumping turbines to provide the extra peaking power needed to meet the requirements of grid system.
To put it in railroad terms, suppose the diesels' dynamic brakes charged up a large bank of batteries housed in a trailing slug instead of disapating the power as heat . That slug could then be used as an additional booster to maintain the train's speed up the next grade without the expenditure of additional fuel. This is the principal of the hybrid drive that is increasingly being used in automobiles.
Solar cells shut down at night. Their power has to used immediately in order to make them economical. It does not pay to store their power, particularly since no conversion process (light to electricity, storage or electricity, regeneration of electricity, transmission of that power, is 100% efficient.

But that would mean that we would have clean power 24 hours a day. If we had signed the Kyoto Agreement we would be working on this right now.

[Leon Silverman]

The purpose of pumped storage facilities is to maintain loading on other power plants. Unlike the relativel small prime movers used in surface transportation (cars, trains and ships), multimegawatt power plants cannot "follow the load". They can increase or decrease their output by only a couple megawatts and hour. Consequently, they have to run at essentially the same full power output all the time. The excess generating capacity is used to fill up the pumped storage reservoir at night. During the day, when these multimegawatt plants' output is insuffficient to provide all the power needs of the grid, the pumped storage water is allowed to flow back through the pumping turbines to provide the extra peaking power needed to meet the requirements of grid system.
To put it in railroad terms, suppose the diesels' dynamic brakes charged up a large bank of batteries housed in a trailing slug instead of disapating the power as heat . That slug could then be used as an additional booster to maintain the train's speed up the next grade without the expenditure of additional fuel. This is the principal of the hybrid drive that is increasingly being used in automobiles.
Solar cells shut down at night. Their power has to used immediately in order to make them economical. It does not pay to store their power, particularly since no conversion process (light to electricity, storage or electricity, regeneration of electricity, transmission of that power, is 100% efficient.

[kevarc]

You just don't get it.

[csxengineer98]

now that is a realy off the wall idea....
i have a question for you dunk....how old are you?
csx engineer

[Anonymous]

transmit the electricy 200 miles to the pumps

[kevarc]

It is not efficent enough to pump the water that far, the loses would override any gain.

And you do not get it, you put the power in the grid. This is generated during daylight hours, when the price is high, you sell it.

[Anonymous]

The solar generated electricty could be trasmitted to a place were there are already
pumped storage. A solar array in the central time zone could pump water in the eastern time zone getting a extra hour of sunlight. Come on guys somebody here must be a fan of "Popular Mechanics"

[underworld]

Try searching for information at Mother Earth News
http://www.motherearthnews.com/

underworld

[:D][:D][:D][:D][:D]

[kevarc]

And treat the water. Boiler water is very picky for power plants, just as it was for steam engines. You can get away with lower water quality for condenser water.

But you do not need water for a solar array. It is already being converted to electricity.

The amount of water pumped at night should not effect the water level in a reservoir, unless it is a very small one.

[dharmon]

QUOTE: Originally posted by jchnhtfd

Then the solar panel problem is also immense. If we suppose you are in the desert southwest, you can figure -- very very roughly -- about 10 kw hours per square metre per day from your facility. So to replace a nice little 500 megawatt power plant (12,000,000 kw hours per day) you need about 1,000,000 square metres. Which is about half a square mile of collector. And a 500 mw plant is a small plant...

And then you'd have to import the water.

[jchnhtfd]

There are some awesome environmental objections to pumped storage facilities which involve the upper and lower reservoirs. If they are existing lakes, the variations in water level pretty will pretty well destroy whatever environmental values there might be; if either reservoir requires new storage, that's going to submerge a lot of land, or play havoc with an existing river, or both.

Then the solar panel problem is also immense. If we suppose you are in the desert southwest, you can figure -- very very roughly -- about 10 kw hours per square metre per day from your facility. So to replace a nice little 500 megawatt power plant (12,000,000 kw hours per day) you need about 1,000,000 square metres. Which is about half a square mile of collector. And a 500 mw plant is a small plant...

[kevarc]

Thank you Overmod. To add to the mix, there are companies working to store A/C in storage type batteries. Very interesting, but a long way till is is viable. Another thing being done is pumping air into reservoirs at night and then using the compressed gas to drive a turbine during the day. Fuel cells are interesting, but far from practical applications.

Remember, Dynamics can backfeed a system, but it can only supplement what is needed, It will never cover the load.

[harpwolf]

If you were isolated, then backpump. But if you're on the grid, buy low, sell high [8D]

If your electric railroad were solar, you'd build twice the capacity you needed. While the sun is shining you'd sell half of it back to the grid (at peak prices [8D]) and when the sun set, you'd buy all your power back off the grid, (at nighttime prices [8D]).

That's better than backpumping because backpumping is less than 100% efficient, while selling peak and buying off-peak is 137% efficient because you're selling for $55 what you buy back later for $40.

[Overmod]

dunkirk, pumped storage is almost always intended as a peak-shifting technology, not as a means of cost-effective energy storage. Listen to these guys -- they know their business.

Remember that in most cases there is a fairly large cost to construct these facilities, even when the local/Federal EPA et al. allow you to use existing bodies of water at high elevation as the basis for your reservoir system. Now, you have to ask whether it makes better sense to build a large solar array -- which is almost always intended for installation far, far away from areas where there is lots of water on the surface (where it evaporates to clouds, which block much of the photoelectric insolation...) -- and devote its entire output to pumping water uphill rather than converting to phase-corrected AC and driving a proportional share of daytime peak with it. Remember that with pumps you get losses, both electrical and physical, both ways, whereas with direct conversion both the amount and the proportion of the loss would be less.

Now, if you were somehow to have a large generating capacity far from the grid, and used that electricity to pump water from places that didn't need the water to places that did, and then arranged for water use THERE via hydro, you might be able to piece together a rationale for construction. But I'd need extensive convincing with some very, very hard numbers...

dharmon, the problem isn't the IV, it's that he's been pushing the button on the pain pump a bit too often... ;-0

[kevarc]

Chris, at night we do pump water "uphill" back into the lakes at night, again cheaper power. They do this a lot in the west.

Dunkirk - this is the way it is - Power is a lot more expensive during the day, why would you use the expensive power to pump watrer to use at night. That is just plain dumb. You put it into the grid. Then you use cheap off-peak power to pump water uphill. That is they way it is done. Look at the price chart in the link I put in my earlier post. Solar power is not cheap, it is one the the most expensive of the renewable power sources and higher than any of teh normal power sources.