Development of fuelless powerplants?

MWadwell wrote:But DC produces AC EM, and we know that AC EM will be targetted by the Rakurai....


Later,
Matt

It was specifically stated that this was not something that Safehold could use. It is what could be used on Earth.

Aegis99 wrote: His premise boils down to that renewables (especially photovoltaics) create a very unstable electrical grid. not because of when it is NOT operating, but actually the problems come from when they ARE running. If you have the time, it's a good perspective

The grid is designed for steady power generation and viable load, "renewables give variable generation causing greater demand on spinning reserve, especially those components with the fastest throttle response (possibly what keylime was referring to as ramp rate). For these response rates non-spinning reserve might as well not exist as that will take 12hours to 5 days to add power to grid, as adding a genset not synched to the grid will do very bad things (this wrecks improperly wired home generators after every power outage).

As for trying any but a basic solar heater for hot water for an afternoon shower, I believe that all such systems used today require active pumping of the fluid.

Thucydides wrote:Even in developed nations like Germany or the US (where "Green" has taken root) it is very difficult to deliver the "Green" energy to market. The grid needs to be radically upgraded to allow for long distance transmission of energy, not to mention evening out the delivery of energy to the grid. Superconducting transmission cables and an advanced switching network to match fluctuating supply and demand are likely needed to make this work.

Germany has had several instances where fluctuating winds in the North Sea have destabilized the grid (sudden mismatches between demand and supply), and in Ontario there is a large scale building program to have gas turbine generators on standby (running at "hot idle" 24/7) to kick in instantly if the wind farms suddenly fluctuate due to the wind dying down. The opposite problem of sudden surges in the wind is solved by venting steam at thermal and nuclear plants, and spilling water at hydro stations. If all else fails, electrical energy is "dumped" for $.04 KW/h to New York State, even though the Ontario taxpayer pays $.135 KW/h for "Green" energy and $.08 KW/h for conventional energy.

Something to remember the next time a politician or a crony capitalist wants to spend your tax dollars on "Green" energy.

It's not just Ontario which has 'standby' power. For wind, 1MW of standby power is required for every 1MW of generation and that is true everywhere. Solar has a similar requirement although not quite as stringent because the insolation forecasts are more reliable than the wind forecasts. Still, a power system needs a certain amount of reserve power in order to cover what are known as contingencies. Failure to cover these contingencies adequately leads to collapse of the system from either lack of power or low voltage. For a large industrial process, a sudden removal of power can lead to very dire consequences, very rapidly. Fukushima is a very good example of the extreme end of the consequences.

This is an interesting discussion from a number of viewpoints but one of the things that is clear is that people have no idea of how much energy an industrial society really requires. And this energy needs to be reliable, clean, reasonably priced and available all of the time.

All of this is moot for the planet Safehold at this time but will surely come up again a few books from now as a truly industrial economy is built up planet wide.

Here is a public web site where one can see real time graphs for the load in NE, CT and CONVEX. The latter is a consortium of power companies located in CT and western MA.

www.cvx.com

One more post about 'dumped' power. Usually, dumped power is zero cost to the pool that takes it. However, if one is in the position of the Danes whose wind driven system causes both immense amounts of dumped power and extreme shortages which, if not immediately dealt with, would cause their system to collapse. Lucky for them, they are heavily interconnected to the surrounding countries and can lean on 'inadvertent' power supplied unwillingly by their neighbors during shortages and can export overgeneration to those same neighbors when the wind begins an unplanned pick up. Due to the fact that all of their neighbors have also invested heavily in wind and solar energy, those systems, in many instances, suffer from the same overgeneration or undegeneration problems as the Danish system at the same times. This limits the amount of power that these systems can either absorb or deliver. Once again though, the Danes have lucked out by being connected to the Swedes and the Norwegians whose systems are largely hydro powered. Hydro power responds very fast. However, the sudden changes in the power flows of the systems can and do cause dangerous voltage conditions and power flows so the Norwegians and the Swedes are forced to react to protect their own systems. There is, however bad news for the Danes. Both Norway and Sweden, tired of having to constantly horse their systems around to take care of problems that the Danes inflict on their systems, are charging the Danes 200 Euros per MW, in both directions. This means that the Danish system is actually running at a loss or, at best on a break even basis for their massive investment in 'free' power.

=2014/03/06=

For a DC grid, there are few "syncing" requirements.

Also, if the main distribution is not only DC but via shielded cable, there are very few EM waves generated, even when the current flow varies with load.

Not NO EM or NO syncing requirements -- just fewer and milder ones which MAYBE would be ignored by the bombardment system.

R
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Castenea wrote:

Aegis99 wrote: His premise boils down to that renewables (especially photovoltaics) create a very unstable electrical grid. not because of when it is NOT operating, but actually the problems come from when they ARE running. If you have the time, it's a good perspective

The grid is designed for steady power generation and viable load, "renewables give variable generation causing greater demand on spinning reserve, especially those components with the fastest throttle response (possibly what keylime was referring to as ramp rate). For these response rates non-spinning reserve might as well not exist as that will take 12hours to 5 days to add power to grid, as adding a genset not synched to the grid will do very bad things (this wrecks improperly wired home generators after every power outage).

As for trying any but a basic solar heater for hot water for an afternoon shower, I believe that all such systems used today require active pumping of the fluid.

SWM wrote:

MWadwell wrote:But DC produces AC EM, and we know that AC EM will be targetted by the Rakurai....


Later,
Matt

It was specifically stated that this was not something that Safehold could use. It is what could be used on Earth.

Oh, O.K.

I just thought that this forum was called for "Safehold" for a reason.....

Seriously though, I am finding this discussion interesting.

Castenea wrote:The grid is designed for steady power generation and viable load, "renewables give variable generation causing greater demand on spinning reserve, especially those components with the fastest throttle response (possibly what keylime was referring to as ramp rate). For these response rates non-spinning reserve might as well not exist as that will take 12hours to 5 days to add power to grid, as adding a genset not synched to the grid will do very bad things (this wrecks improperly wired home generators after every power outage).

As for trying any but a basic solar heater for hot water for an afternoon shower, I believe that all such systems used today require active pumping of the fluid.

This post is so far off I don't know where to begin.

First off, ramp rate is the percentage of it's total capacity a generator can increase/decrease by. Per minute. No plant in the world takes days from 0 to full capacity. To see how badly you're underestimating, look at this, and note that the slide 4 data is from the 80s http://www.wecc.biz/committees/BOD/TEPP ... gRate.pptx
Notice this data is for coal. Coal plants are slower than all other types of thermal generators except nuclear.

Second, the grid is operated for variable power AND variable load. More power than load into the system is just as bad as more load than power. Both will cause voltage collapses, generators slipping poles, and all sorts of other fun stuff. Grid operators at the balancing authorities alter generator outputs in real-time to avoid both situations. There's some interesting efforts being put into making at least part of the load controllable by the operators, by paying industrial loads to shut down during peak usage instead of paying generators to turn on. The jury is still out on how well those test markets are doing though.

Third, look up how fast both spinning and non-spinning reserve has after notification from the grid operators to come online before getting hit with huge fines for non-compliance. Hint: it's a LOT faster than you appear to be thinking.

kbus888 wrote:=2014/03/06=

For a DC grid, there are few "syncing" requirements.

Also, if the main distribution is not only DC but via shielded cable, there are very few EM waves generated, even when the current flow varies with load.

Not NO EM or NO syncing requirements -- just fewer and milder ones which MAYBE would be ignored by the bombardment system.

I can maybe believe you could transmit the power without giving off EMR. But that still leaves the issue of what use could you possibly have for it? A single electric motor out of alignment could create a spark gap powerful enough to get detected form orbit. Would be kind of silly to build a factory that could with a single error in maintenance cause the Rakurai to wipe out a continent....

keylime314 wrote:This post is so far off I don't know where to begin.

First off, ramp rate is the percentage of it's total capacity a generator can increase/decrease by. Per minute. No plant in the world takes days from 0 to full capacity. To see how badly you're underestimating, look at this, and note that the slide 4 data is from the 80s http://www.wecc.biz/committees/BOD/TEPP ... gRate.pptx
Notice this data is for coal. Coal plants are slower than all other types of thermal generators except nuclear.

Second, the grid is operated for variable power AND variable load. More power than load into the system is just as bad as more load than power. Both will cause voltage collapses, generators slipping poles, and all sorts of other fun stuff. Grid operators at the balancing authorities alter generator outputs in real-time to avoid both situations. There's some interesting efforts being put into making at least part of the load controllable by the operators, by paying industrial loads to shut down during peak usage instead of paying generators to turn on. The jury is still out on how well those test markets are doing though.

Third, look up how fast both spinning and non-spinning reserve has after notification from the grid operators to come online before getting hit with huge fines for non-compliance. Hint: it's a LOT faster than you appear to be thinking.

Your points are very solid, but an increase in renewabes requires an equal amount of reserve be built because grid operators cannot count on the renewables staying on. In the current market that means natural gas turbines, and we're not talking combined cycles plants either... The NG plants that are used to offset wind farms are single cycle, and have a thermal efficiency below 30%. Also, because these rapid response turbines are designed to not run all day long, they have fewer operational hours in a year to recuperate their costs. If your NG plant only runs 2000 hours a year, but costs as much money as a plant than runs 4000 hours a year then the plant that runs for 1/2 as much time will have to charge twice as much money to stay in business. This is part of the hidden costs to renewable generating sources.

Aegis99 wrote:Your points are very solid, but an increase in renewabes requires an equal amount of reserve be built because grid operators cannot count on the renewables staying on.

As was stated elsewhere, if you are building a new power generator of any kind you need to have that reserve. So the cost of the reserve is the same no matter what kind of main power generator you build.