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Eric E wrote: 4) A heavy burden on the electrical grid due, in part, to the electrification of transportation will force newer, more efficient power plants into production financed by the displacement of oil.

I do not think the electrification of transportation will force newer power plants into production. Peak to valley ratio of the grid energy requirement is about 1 to 0.5. Take FP&L's 24,000MW capacity, for example, if this maximum capacity is just enough to meet the peak demand during the summer, the off-peak demand should be 12,000MW. Let's be more conservative since many people there keep the AC on during night, and increase this number to 16,000MW. Still this means FP&L has 8,000MW of surplus during off-peak hours. The Volt needs about 2KW of power for 4 off-peak hours to charge its battery pack from 30% charge to 80% charge. Therefore, FP&L can support 4 million Volts without building new power plants. The number increases to 8 million if charging hours are staggered to two 4-hour sections.

If this happens FP&L will be very happy since it earns money from otherwise wasted energy improving its bottom line. (It is dumping a lot of energy into the ground during off-peak hours to synchronize all the generators on the grid.) Also, this means reduction of CO2 emission since Volts on the road mean less number of cars with ICE and no additional tail pipe emissions for at least 40 miles per vehicle.
 

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Excellent point.

So what do we do with the extra $700 million/day?:)

and...

"It (FP&L) is dumping a lot of energy into the ground during off-peak hours to synchronize all the generators on the grid."

Please explain...
 

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Eric,
Unlike DC power sources such as batteries AC generators cannot be connected together in parallel unless they are synchronized. In addition to voltage their frequency (phase) must be precisely matched. Force of water or steam drives generator’s turbines. When energy demand gets higher, the turbine (rotor) gets heavier to turn, or vice versa. When a generator is rotating at a speed sending out 60Hz, 10,000-volt electricity, for example, its speed becomes slower (lowering frequency and voltage) as demand gets higher unless the water or steam flow increases. However, water or steam flow cannot be controlled quickly and precisely enough to respond to ever changing demand. So, a portion of output from a generator is discharged into the ground to stabilize the demand since electricity can respond quickly and precisely. Even though the water or steam flow is lowered (though slowly) for the reduced demand during off-peak hours, still the grid has to dump a lot of energy into the ground. This is the reason why utility companies charge 1/3 to 1/5 of day rate for off-peak hours. They are just happy to sell the electricity (at whatever price) that they have to waste otherwise.

If 4 million Volts are not realistic right away, then we can make stationary UPS’s using the A123 battery pack so that we can store the off-peak energy and use it during peak hours by cutting our home off from the grid, thereby reducing the burden on the grid during the peak hours. If FP&L's 24,000MW max capacity is short by 1,000MW causing black/brown outs during peak hours of hottest days of summer in Miami, for example, then FP&L can have the UPS installed at 1 million or so households, which is cheaper and faster than having to build a new nuke plant.
 

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Why Not For Some Total Electric?

90% of my driving is single occupant with a 40 mile round trip. If the goal was a 50 mile round trip with two occupants then my numbers would be more like 95%. Why should I drag around another engine for less than 10% of my driving? I could either own or rent a vehicle for those special trips. I can't believe that mature adults couldn't understand this logic.
I understand that cuts out the petroleum industry, but we don't have buggy whips in our vehicles either.
Save the cost, save the weight, save the space, save the earth!
 

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Well, if you are going to get all sanctimonious why don't you get yourself a bike if most of your driving is such a short distance? That would save the earth even more! ;)

I think the hybrid approach is more likely to appeal to the masses who would like to save the earth AND have the freedom they had with their old-technology cars. Don't worry, there will be quite a few all-electric options out there by 2011.
 

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Electric Grid Clarifications

G35X

We will need to see some verification of your supposed electricity grounding during off-peak periods. Certainly not anything I am familar with.

You are correct, that in the grid, power is generated as 3-phase AC, and all the generators in the grid have to be "synchronized", such that they all become electrically "coupled" together (all rotate at exactly the same speed). For Florida, the grid is controlled by the system ISO (independent system operator) for the region (FRCC). I approximate summer capacity of the system is 53,000 MW (this equals about 71 million horsepower).

http://www.eia.doe.gov/fuelelectric.html

Since all these turbine generators are electrically coupled together, I estimate the system has about 20,000 tons of rotating machinery coupled together. When you flick on a big motor and its dims the lights, that's due to current draw in the local power lines. The 20,000 tons of rotating equipment doesn't flinch.

You seem to indicate that the machinery can't react to load changes, but that isn't true. First, the load changes in a large grid are typically not sudden, but happen at a rate of several percent per hour. But even in emergencies, a steam turbine can trip off line in less than 0.05 seconds (if a coupling breaks while the steam turbine is producing 500 MW, it will overspeed to destruction in less than a second, like driving full speed in a car and depressing the clutch). So I don't buy your theory of the equipment being too slow to adjust to the load. For a better look at a system's operation, see the CA ISO.

http://www.caiso.com/

Here you can see the power used in the grid on a daily basis. Its low was about 20,000 MW at 3 am, and the peak was almost 30,000 MW.

For the grid, nuclear plants are operated at full load around the clock. Next are coal plants which typically operate at full load during the day, but operate at part load in the evenings. Many natural gas combined cycle power plants start-up in the morning and shutdown in the evening as power demand decreases. Other forms of power (wind, solar, hydro) are added when it is available.

Note that most power plants have their best efficiency at full load.

At night, utilities have excess capacity that is either at part load (which is inefficient) or shutdown. They would like to find ways to even out the load demand, so that they can operate 24/7 at full load. Thus they provide incentives for customers who will agree to take "off-peak" power.

Note that as the system load becomes steady, the utilities will want to build more nuclear plants and coal plants, because of their low fuel costs. FP&L petitioned within the last year to build 2 new coal plants, but was denied by the FL PSC due to uncertainties regarding CO2 emissions. They have since petitioned for two new nuclear plants and have the FL PSC approval.

http://www.fpl.com/

With the Volt using 6 hours to charge 8 kwh into the batteries, the demand is 1.33 kW. Therefore, 1 million Volts, all charging at night, would add 1330 MW of load. As you can see in CA, between 11 pm and 5 am, this added load would result in a system load between 21,000 and 26,000 MW, well below the daily peak of 30,000 MW.

Since this load demand is indicative of other US ISO's, the current electrical system in the US has a great deal of capacity to charge electrical vehicles like the Volt during off-peak hours.
 

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Can I then therefore assume that three phase AC provides 1/3 more current over the same size wire than single phase?

Is that the benefit and reason for three phase?

Sorry about all the questions but this is fascinating.
 

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All this energy dumping talk has me wondering. I thought the grid already had lots of storage capability already in place to handle fluctuations in power consumption and production. We have capacitors (for quick changes), generators, battery banks, LPG plants that can fire up quickly and my personal favorite pumped storage hydro that can accept huge amounts of excess energy to move water up to higher reservoirs for later use (man-made hydro).

I wish I had access to a grid expert that knew most of the workings including the amount of dumping, storage, types or storage, future expansion plans, high voltage powerline infrastructure, etc. Is there such a guru around? If so, please jump in once in a while and clear up the misunderstandings.

My vision of future smart grids consists of mostly solar (both thermal and PV), wind, free-hydro and fossil fuel backup for the generation side and pumped storage hydro, advanced batteries, compressed air storage, biodiesel and other technologies (possibly even hydrogen) for the storage side. While I could put hydrogen and biodiesel on the generation end I think of them more as carriers of energy.

Of course we would use our existing infrastructure because it will take a long time to build out the new grids but I feel we need get off of fossil fuel burning as quickly as possible (even if that is 50 years from now). We do have a few hundred years of coal remaining but when compared to solar thermal it's just plain filthy.

What I would really like is a good debate on why we can't start building out massive amounts of pumped storage hydro. We already have quite a lot but if we are going to seriously use renewable sources of energy we are going to need a lot more. This infrastructure can be useful for hundreds of years and can be built just about anywhere. I'm aware that our natural, free-hydro resources are just about fully utilized but pumped storage hydro is a different animal, basically two huge reservoirs of water separated by a few hundred feet in elevation. The turbine generators are efficient and last for an unbelievable amount of time (new turbine designs use water bearings). Anyone? We could build these things out and make them as beautiful as Roman aqueducts. Good old fashion public works projects that would use US labor building useful US infrastructure. The disadvantage is that evapoation reduces the efficiency of the system but if you build them in rainy environments they can recover a lot of that loss. Even with evaporation pumped storage systems are over 70% efficient. They are clean, environmentally safe, technically simple, can provide huge amounts of power for long durations and can be turned on in a few seconds.
 

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100mpg Series Hybrid !!!

Bill,
Not that 60% vs 70% changes the argument, but the attached link shows the efficiency improvements for several new combined cycle gas-turbine power plants in Japan and 60% is right at the state of the art; so your numbers are right. But at 85%, hurrah for cogeneration; especially if the steam heat replaces an oil burner.

http://www.power-technology.com/projects/yokohama/

So with coal at 40% efficiency and a modern natural gas plant at 60%, then a Series Hybrid vehicle with a 40% efficient on-board turbo-diesel gen-set sounds really good. If the gen-set runs constantly, it allows you to downsize the battery pack to just a few kW-hrs; maybe $2000 of NiMH or $600 of SLA (sealed lead-acid) batteries, but you still get THREE-TO-FOUR times the fuel economy!! Both Azure Dynamics and AC Propulsion advertise over 90% efficiency for their electric drive systems from battery to wheels, so overall the Series Hybrid is 36% efficient whether it's driving in the city or on the highway, while a gasser averages 10-12%. Plus regenerative braking and eliminating idling losses easily adds 20% more, so in reality it's 43% vs 10-12%.

THIS MAKES A 25MPG CAR INTO A 100MPG CAR!

CAN SOMEONE EXPLAIN TO ME WHY WE HAVEN'T BEEN DOING THIS FOR THE PAST 50 YEARS !?!? The cost to build such a "non plug-in" Series Hybrid has to be dirt cheap (remember an AC induction motor only has ONE MOVING PART). How could the Big Three overlook a way to make a $5000 car for so long?

Dr Mark

I looked at your link at Winkipedia. In the article, they indicate a the following:

"The thermal efficiency of a combined cycle power plant is the net power output of the plant divided by the heating value of the fuel. If the plant produces only electricity, efficiencies of up to 59% can be achieved. In the case of combined heat and power generation, the overall efficiency can increase to 85%."

So for a pure power plant (electricity production only), the efficiency can be up to 59%. This in the important efficiency to remember, as it is the conversion of fuel to electricity, which is what the Volt requires.

Combined heat and power (CHP) applications are also referred to a cogeneration facilities. A typical CHP facility might be a combined cycle power plant located at a paper mill. Besides producing power, the facility supplies medium pressure steam to the paper mill to dry paper coming off the process. Now the paper mill doesn't need to burn fuel to produce steam.

In this scenario, the actual fuel utilization factor increases (up to 85%, as mentioned in Winkipedia), however, the electrical efficiency decreases, as the medium pressure steam is used for heating instead of power generation in a steam turbine.

CHP is a great technology, as it helps us reduce the use of fuels, however, CHP efficiencies are not the same as a power plant efficiency, so they can't be compared directly to an ICE. Note that even ICE's can be used in CHP applications, where the heat from the coolant and exhaust can be used to make hot water. One application I know of was an ICE driving a generator at a glass plant, where the glass had to be washed after it was formed and cooled. I'm sure the CHP efficiency for this ICE application could be 80+% as well.
 

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BillR,
Not being an insider of the industry I cannot show hard numbers as to how much energy is dumped into the ground. But, automatic voltage regulator (AVR) and neutral-point grounding to maintain quality of product on the grid operate by wasting energy. If you say the following equation is correct, I will be happy to retract what I said:

energy generated = energy billed + energy lost in transmission by resistive and capacitive components + energy used internally

If the left side is greater than the right side, where does the difference go?

To cover the base load, nuke plants and coal-fired plants (and water current plants) are always running at their maximum or close to maximum capacity because adjusting their output is difficult. Much easier to adjust or even shut down are gas-fired plants, oil-fired plants and hydro (including pump-up) plants. Yes, as you pointed out, the flywheel effect of the generator rotors absorbs short-term fluctuations of demand. It is also possible to adjust output with some preparatory time (30 minutes?). Here comes the art of power demand prediction. You forecast demand in the coming 24 hours (?) and fine tune the output on the fly 30 minutes (?) ahead of time. I think power plants generate a little bit more power than the prediction requires and dump the excess as buffer. I looked at the California ISO site. Thank you for directing me there. I noticed forecast is very close to the actual. What I did not understand is why they maintain the available power so high if the forecast is so accurate. Maybe they cannot shut down some of the big plants. Then, where does the excess go? Also, I do not understand the reason why they tell the public by the Conserve-O-Meter that conservation is helpful even though demand is so much lower than the available power. From the business standpoint they must want to keep the consumption as close to the max as possible.

Anyway, the situation will change dramatically thanks to GM/A123, Mitsubishi/GS, Subaru/NEC and Toyota/Panasonic alliances, which will bring us high-capacity, low-cost batteries. By using those batteries we can make high-capacity UPS’s, with which we store enough energy during off-peak hours to let us off the grid during peak hours. In this way we can shave the peak thereby reducing the peak demand so much so that eventually we can decommission some of the most offending coal-fired plants. This is quite a contrast to having to build more new (nuke) plants. Just think of the economic and employment opportunity in the manufacture and installation of the UPS, if we are to make and install, say, 5 million of them nationwide to shave some 10GW (more than 10 nuke plants' capacity) of power from the peak.

In addition, we are witnessing improvements in efficiency of solar cells. Mitsubishi Electric made announcement about a month ago that they achieved 18% efficiency. Even more encouraging is the UoD/DuPont cell, which is said to be more than 40% efficient.
By combining these solar cells on our roof, the UPS and off-peak charging we can be off-grid for a good part of a day.
 

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In addition, we are witnessing improvements in efficiency of solar cells. Mitsubishi Electric made announcement about a month ago that they achieved 18% efficiency. Even more encouraging is the UoD/DuPont cell, which is said to be more than 40% efficient.
By combining these solar cells on our roof, the UPS and off-peak charging we can be off-grid for a good part of a day.
Don't forget that these technologies you mention are still too expensive to produce when compared with other alternatives. Nanosolar is the most advanced solar technology that's in mass production today (started a few months ago). Instead of semiconductor fabs they use a printing press like manufacturing process. They claim to be able to produce at 99 cents per Watt. At this cost PV solar is a no-brainer alternative. The past killer of solar was not the efficiency but the cost. We have enormous solar resources here in the US. Even at 5% efficiency we could easily provide all of our energy needs and most people wouldn’t be aware of the loss of desert. Now that a cheap manufacturing method has been brought to market we can roll this stuff out like newspapers.

Expect huge news on this soon. Something like: Government: Nanosolar, here is 100 Billion dollars please build as many solar factories as humanly possible and dedicate the entire production to covering our deserts. Nanosolar: Will do boss.
 
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