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Author Topic: UK gas powered car less CO2 than electric ?  (Read 9849 times)

Offline CliffordK

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Re: UK gas powered car less CO2 than electric ?
« Reply #25 on: 01/02/2012 23:49:28 »
It is even hard to vary the output of a coal or NG plant, at least with short-term variability.  Presumably one could program it to have peak output at the same time of a predicted peak demand on a diurnal basis.

The government likes to also run the big hydro-electric plants at a constant rate (base load power), but it would seem that hydro would be perfect for variable load power.  Perhaps coupling a large base-load generator with a smaller variable load generator, with the goal of maintaining an average river flow over a 24 hr period.

Obviously average flow rates vary by the season in places like the Northwest USA, but fortunately, in the winter when heating demands are the highest, flows are also generally the highest.

I certainly don't want the government to start discharging my EV car without my permission.  And, my charger is designed as a 1-way device. 

The local power company is discussing variable power rates, with cheaper rates at night, and higher rates during the day.  In that case, I would certainly put a timer on my charger to kick it in at midnight, for example to capture the cheapest power rates.  I may do that anyway.  If they had a buyback, I might consider uploading power at noon (on days I wasn't using the car) and downloading power at midnight.  What would the efficiency be?  80% max?  However, the life of batteries is in part dependent on depth of discharge and cycles.  If my net savings per cycle would be on the order of 1 dollar, I don't think I would choose to allow diurnal cycles as wear on my battery packs would likely be greater than the diurnal cycling.  And, of course, if something came up in the afternoon and my vehicle was discharged, I'd be out of luck.  Rapid 1hr charging might help some, but I don't have that capability. 

Anyway, I'm still convinced that the best place to intentionally vary the power generation is to install a small variable power module in the dams.  Would it cause more silting? 
 

Offline wolfekeeper

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Re: UK gas powered car less CO2 than electric ?
« Reply #26 on: 02/02/2012 00:10:09 »
You mean Dinorwig, it's a 1.8GW hydro peaker plant in Wales.

http://en.wikipedia.org/wiki/Dinorwig_Power_Station

Also peaker plants in general, are specifically designed to be fast start power generation:

http://en.wikipedia.org/wiki/Peaker_plant

And the idea of the car thing, is that you can CHOOSE to sell (some of) your car's electricity that you bought at base-load cost, back to the grid and make a profit. You don't have to though. Peaking electricity is usually priced at several times higher price.
 

Offline Geezer

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Re: UK gas powered car less CO2 than electric ?
« Reply #27 on: 02/02/2012 00:14:41 »

I certainly don't want the government to start discharging my EV car without my permission.


It would not be without your permission. There would have to be a system that allowed you to set a price for the energy you supplied. At a certain price, you would be happy to sell it!
 

Offline CliffordK

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Re: UK gas powered car less CO2 than electric ?
« Reply #28 on: 02/02/2012 01:13:04 »
I certainly don't want the government to start discharging my EV car without my permission.
It would not be without your permission. There would have to be a system that allowed you to set a price for the energy you supplied. At a certain price, you would be happy to sell it!
Like I said, I would be more willing to charge during off-peak hours than to resell the electricity.

However, if the power company offers $1 per discharge cycle on my batteries.
And the battery pack is valued between $3,000 and $20,000.

And, the power company wants to discharge my car at the time I'm most likely to want to use it.

I might choose not to add the extra unnecessary discharge cycles.
 

Offline wolfekeeper

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Re: UK gas powered car less CO2 than electric ?
« Reply #29 on: 03/02/2012 01:23:11 »
However, if the power company offers $1 per discharge cycle on my batteries.
And the battery pack is valued between $3,000 and $20,000.
I don't think you're quite getting it. At peak load, the power company probably offers more like $0.6-$0.8 or more per kWh, not per discharge cycle. So if it's 50kWh battery, then your battery charge is worth $30+.

The situation is that the power company is desperate for electricity, if they paid $0.2 per kWh nobody would build peaker plants, and nobody would give them any juice!
« Last Edit: 03/02/2012 01:24:58 by wolfekeeper »
 

Offline Geezer

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Re: UK gas powered car less CO2 than electric ?
« Reply #30 on: 03/02/2012 08:32:16 »

The situation is that the power company is desperate for electricity, if they paid $0.2 per kWh nobody would build peaker plants, and nobody would give them any juice!


That's true. The "spot price" for electricity (in the US anyway) can be incredibly high, and it explains why some utility companies have invested heavily in energy storage systems.
 

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Re: UK gas powered car less CO2 than electric ?
« Reply #30 on: 03/02/2012 08:32:16 »

 

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