plug-in states and ghg

Hmmm, sounds like you are anti petroleum - interesting. Then the question to you is - how do you think the Volt was produced? Answer: petroleum. You can not ignore nor escape that fact.

DBCassidy

 

GreenChoice sounds interesting. Problem is, even if you purchase their product over the grid, you can not claim that ALL of your electricity is petroleum free. That would be a very foolish assumption and thought process.

DBCassidy

 

Very good question indeed.

Your rationalization also applies to the Volt and the Leaf. Both of these cars are bad for the environment, especially in the mid west (coal generated electricity is the norm).

DBCassidy

 

Do you think your Volt was manufactured using no petroleum? (That would be are very green approach to producing the Volt) You would reply, of course not, then the realisation sets in: I can't get away from petroleum in my life. So, even if you use a small amount of gas, or any gas at all, your Volt could have never been built without petroleum.
Those are the cold, hard facts.

DBCassidy

 

I rely on the national lab data studies. In the end we have to accept that conclusions are best estimates, with inherent uncertainties we can try to quantify.

That said, I found the coal plant efficiency argument specious.
Am I wrong to conserve electricity, since it might lead to plant inefficiency ?
Is your presumed use of wind power causing the same ?

Unfortunately, the sad state of affairs in the US is that coal plants will only shut down when they are unprofitable. That they go through a transition of further inefficiency on the way to closing is unfortunate but currently unavoidable.

 

Coal plants, with the low price of natural gas, could very well shut down due to being unprofitable. Blomberg Businessweek also ran an article concerning solar in the U.S. now with the elections over, tax subsidies, and credits will probably also go away. Natural gas prices and the big energy producers (the investors) could really put a big dent in solar expanding. Big energy sees solar as a threat to their business plan. Also, there is no national streamlined green energy policy in this country when compared to Germany.

DBCassidy

 

Yeah, unfortunately the repubs hold green energy subsidy hostage every time budget wars erupt. I perosnally think the right thing for the dems to do is scrap all subsidies, but they have their own special interests to pander.

In a sane world, we would tax carbon to pay for climate change and all subsidies would end.

 

The best national study I know looking at the impact of marginal loads is:
http://energyenvironment.pnnl.gov/ei/pdf/Impact%20Assessment%20of%20PHEV%20on%20US%20Power%20Grid.pdf

Still not very local, and making strong assumptions. They start off by ASSUMING that none of the PHEV load is attributed to renewables, be it hydro, wind or solar. They state

And for a single car one might be correct in assuming the margin demand does not fill the gap, especially immediately. What they ignore is that with predictable increases from off-peak demand, say from PHEV nightly charging, there can be increased installation/use of renewables such as wind, backed with NG peakers (which they need for day peak demands anyhow). Otherwise the systems owners may not want to add them and let coal/nuke cover the nighttime baseload and just use gas peakers for the day.

Still the study found that most areas (including you in NM) the PHEV will decrease the average carbon output of their regional grid (since the margin is mostly NG), with the only major increase being for Ca/NV where nighttime charging would have 4% increase in carbon -- but that is just because their grid is already very green. (Note that in keeping the OP, they did model the distribution of vehicles in a non-uniform maner with more in CA/NV but based it as a fixed fraction of registrations, not a "green" based distribution.

The suggested a "carbon tax" that would help shift the economic model so dispatch is to greener lower ghg sources.

I was not saying that conserving was wrong, its just that the analysis is complex because when coal plants efficiency are included 1kWh of marginal impact is not just about the source used, but where/when.

With respect to wind causing inefficiency in coal plants, it absolutely does. There was a recent study by argonee on it
Government Lab Finds Wind Energy Not Meeting Carbon Emission GoalsInstitute for Energy Research | Institute for Energy Research
which shows that that GHG impact of adding wind in areas with high coal generation is not a 1-1 gain because of the efficiency lost, e.g. with their model adding 21TWh of wind would only lead to a new ghg reduction equivivelent to a net reduction in coal plant of 15TWh. However, that is still a significant reduction.

 

Posted that in another thread:

Week's worth of Volt stats | PriusChat

The Leaf won't meet my range requirements and the PIP doesn't meet my EV range or power/quality of drive requirements even if I could buy one in my state. Full disclosure: ghg comparisons don't register on my purchase decision radar; hence, I don't have a dog in this fight/pissing match.

 

Great find, thanks for posting that.
I agree some of the assumptions are questionable, but overall very enlightening.
Of course, the 800 pound gorilla in the room is grid level power storage. If that comes to pass prior to 2030 much of this report goes right out the window. It is still good information for current effects on charging and the grid.

 

So, 'smart' charging at night just means more coal use, more pollution, and more power plant profits ?

Who wudda thunk ?!

 

So in order to load level demand, and perhaps (PERHAPS) use a greener and more efficient source energy, you are adding two trips to the battery, or about a 30% energy cost.

Hardly seems worth it.

The implementation also seems unlikely, since it assumes the *EV owner has a battery willing to contribute juice AFTER driving home.

 

Confessing to not having read the whole thread,, I would simply add the following. Electic motors are fundamentally more efficient that an ICE under almost all conditions. It is thermally more efficient. Additionally, electric motors can be turned into generators simply by reversing current flow, as the Prius does in regen, such that they can recapture, in some cases significant quantity of the initial energy.

Finally, electic cars can take advantge of solar and wind when it is available, delaying charging (if possible) until there is excess grid capacity. (the net/net worst contributor to GHG is energy produced, but not used,, the idle spinning capacity for example.). Electric cars can also take advantge of non peak periods to more efficiently use the grid.

One more thing, in a relly smart grid, the cars can not only buy power from the grid, but also sell it back to the grid at times of peak demand/pricing. A well designed regimen could tell the car, buy power to charge when it is $.05kwh, sell it back when it is .$.10 kwh, but make sure I have enough juice int he battery to get to work tomorrow. (also realize that these cars are likely to be plugged in, 23/7, because most cars are not driven huge number of hours per day.)

Good day,

Icarus

 

Did you read the report I cited?.. their projections (if you combine distribution of veichiles with data from figure 5) is than in 2030 only about 20% of the marginal impact of PHEV charging at night will be from coal.

 

Sage, I think you would find some interesting information in the report. You really should read it.
Charging at night tends to use more natural gas, not coal. Although this does depend upon region and yes, some more coal may be used in some regions, but natural gas is the biggest contributor.

In addition, if an economic incentive is placed on energy generation, virtually all regions generate less co2 with overnight charging.

 

The thing about thermal plants, unlike hydro for example, is that they cannot be spooled up very quickly. They need to be kept burning at least at a low fire in anticipation of being used. It is the idle, spinning capacity that is waiting for the (often time very short lived) peak load that is the biggest single wasteful emitter. Plug in could have a significant effect on reducing that idle capacity if there were enough of them, and they were programmed effectively.

We sell ~16 million cars per year in the US in a normal economy. If 25% of them were plug ins, in ten years that would be ~40 million disaggregated battery banks, buying and selling into the grid. All in all, in the net, a good thing.

Icarus