Energy Independence - Andy Grove essay

[p71]

http://www.american.com/archive/2008...lectric-future

Good read on achieving true independence from foreign energy sources by the former CEO of Intel. Author of the catch phrase, "only the paranoid survive."

[mecklen]

Re: Energy Independence - Andy Grove essay

Hmm, he pretty much completely ignores natural gas as a transportation fuel. I also must disagree with his assertion that energy independence is the wrong goal. Clearly, the more of our energy needs we can supply with domestic resources the better off we will be.

The advantages of NG over straight electricity are obvious to anyone familiar with high school physics. Basically, converting NG into kinetic energy (motion) is more efficient than converting to electricity then kinetic energy. I believe electric vehicles are the correct "final" solution, but we're not there yet.

He justifies dual fuel vehicles well, but that applies to NG even better. Also, his vehicle conversion effort would work much better by converting to CNG/gas as we all (here) know.

Overall, a good article. Just replace natural gas as the fuel of choice and it makes perfect sense.

[p71]

Re: Energy Independence - Andy Grove essay

Dr. Grove does understand physics:

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

The point of his essay is that an electric power based transportation system that can use a variety of fuel sources will be more resilient to disruptions (political or economic) than any single source system.

[Steve]

Re: Energy Independence - Andy Grove essay

Electric power plants that use natural gas for electricity production are about 60% or more efficient whereas the internal combustion engine is about 20% efficient. One problem that I see is the energy density of batteries. I even suspect that you can get more energy density with fuel cells and hydrogen than with batteries. There are some hurdles along the way and of course I would rather use CNG for now but I do believe that eventually electric cars will be the way to go if the energy densities are overcome.

[mecklen]

Re: Energy Independence - Andy Grove essay

I would rather use CNG for now but I do believe that eventually electric cars will be the way to go if the energy densities are overcome.

My point exactly.

[Blueflame]

Re: Energy Independence - Andy Grove essay

Wow. Excellent read. Thank you!

[John Mitton]

Re: Energy Independence - Andy Grove essay

Great read, thanks p71 !
I will move this to the Lounge as it is not CNG specific.

[ch4]

Re: Energy Independence - Andy Grove essay

Electric power plants that use natural gas for electricity production are about 60% or more efficient whereas the internal combustion engine is about 20% efficient. ...

This is a hot topic. Please site your sources. Remember: The electricity has to be transported using lines and transformers, all of which decrease the efficiency. Don't forget to include the transformer in the PHV .

[Steve]

Re: Energy Independence - Andy Grove essay

This is a hot topic. Please site your sources. Remember: The electricity has to be transported using lines and transformers, all of which decrease the efficiency. Don't forget to include the transformer in the PHV .

Here is an article about combined cycles which is what natural gas power generators use

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

I was only referring to the efficiency of the power generator but here is an article on transmission lines:

http://en.wikipedia.org/wiki/Electri...r_transmission

I don't know what PHV means but taking a conservative 60% efficiency rating using a combined cycle for natural gas power generators with a conservative estimate of 10% transmission line loss (the above article states 7% loss) gives you 54% at the home.

I don't know how many natural gas power generators there are but I would imagine that the bulk of electricity generated would be from coal fired plants.

[siai47]

Re: Energy Independence - Andy Grove essay

Try this report---It gives some good well-to-wheels efficiencies for various fuels along with emission impacts.

[Andy-Paul]

Re: Energy Independence - Andy Grove essay

I still don't think any of the plug-in guys have carefully considered two issues:
1st, if we currently import 2500 metric tons [1] of Li to the US per year, and the cost is US$2.30/kg (or $1/lb) [1], what effect on the lithium market--not to mention consumer electronics!--is it going to have to build 1-2million electric hybrids/ plug-in electrics at (25x3000)g [3],[2] or 75kg of Li-ion batteries per car? That is 75 million kg or almost 35,100 metric tons of Li, an increase of more than fourteen fold, for the US market alone. Start talking about fleet replacement in these terms--all 250,000,000 vehicles--and the logic fails completely. This is for cars that are only good for about 100 miles/day. Not useful for a three parish minister in North Dakota (among others), is it?
Second, and this is more important from a world view than a US perspective--what good is battery power for the large parts of the world where the grid is either broken-down or non-existent?

Energy independence or energy interdependence is not even close to the issue which is on our plate. The first thing we need to do is to *diversify* our transport fuel portfolio in order to innoculate the world's economy from getting hosed whenever one type of fuel or another suffers price spikes. Andy Grove may posit that electric vehicles benefit from using the output of whatever the generator can burn least expensively, but that still does not address the dangers of having all our eggs in one basket, especially when we own neither the basket, nor the chickens.

Once again it is past my bedtime here on the Atlantic Seaboard, so y'all have at it and I'll catch up tomorrow.

Andy-Paul






[1] http://minerals.usgs.gov/minerals/pu...lithimyb06.pdf

[2]http://www.hybridcars.com/technology-stories/lithium-ion-batteries.html

[3] One AA-battery weighs about 25 grams, according to my kitchen food scale.

[Steve]

Re: Energy Independence - Andy Grove essay

My previous post is awaiting moderation... not sure why.

Google was my friend in coming up with sources. There is a Wikipedia article about Combined Cycle which is the type of thermodynamic cycle a natural gas power generator uses. Efficiencies of up to 85% can be achieved (this assumes that you will use waste heat to heat the buildings, etc) so a conservative estimate of 60% efficiency was used. Also, there is a Wikipedia article about Transmission Lines which states that losses are around 7%. This gives you electricity to the home at around 55%.

But, coal generation still produces about 2 1/2 times the amount of electricity than natural gas (Google again got me to the department of energy web site - I am afraid to put links in my posts for fear of 'more moderation').

I don't know what PHV is, Google wasn't so friendly this time :-(

[Andy-Paul]

Re: Energy Independence - Andy Grove essay

Steve;

Sometimes the spam posting filter kicks in if you have too many websites hot-linked in. Also, PHV means Plugin Hybrid Vehicle.

By combined cycle (CC) you mean the heat given off in the adiabatic stage of one cycle is used to put heat into lower heat generation, right? (I took thermo with a new baby in the house, so it's a little blurry). CC generation can work with coal, too, but hasn't been used in the past because coal has been so cheap and (let's talk irony, here) efficient because the particles emitted during combustion slow heat loss to the atmosphere. A gas flame is so clean that the heat dissipates much faster unless you *do* use some sort of CC to slow diffusion. Also, NG generation was scratch engineering vs. coal which has a longer history so it tends to be evolved engineering.

Come to think of it, heat loss vs. petro might be a source of the lowered FE of a nat gas refit (d'oh!). Can one of you guys with mechanical engineering thermo help me out on this? My thermo was geared toward heat treatments for microstructure.

Andy-Paul

[Steve]

Re: Energy Independence - Andy Grove essay

Well I am way out of my league on this. I had one thermodynamic class and it was more of a distraction for my EE classes. What I understand, coal fired plants are specifically heat engine type Carnot cycles. A combined cycle uses a heat engine along with a turbine engine with the waste heat from the turbine to help the heat engine. A turbine engine uses gaseous fuel in the combustion chamber so I guess the turbine side of a power generator could use natural gas and the heat engine side of the power generator could use coal.

I would be very surprised if a PHV can be more efficient than a strictly coal fired power plant.

[Andy-Paul]

Re: Energy Independence - Andy Grove essay

I would be very surprised if a PHV can be more efficient than a strictly coal fired power plant.

Agreed: perhaps the PHV idea is to plug back into short hop grid instead of going to the high wires with it. Also, the idea might be to get coal out of the generation mix as quickly and as thoroughly as possible--not betting the farm on that one

If the CC gas system can turn a turbine, then why can't the same thing be done with the leftover heat from a coal-fired system? I have seen IR photography on some of the coal burners around here, and there certainly was heat to spare (15-20 yrs ago).

But, back to my original point, independence from imported oil won't mean diddly if we just switch one energy monoculture for another, will it? I believe in two automotive fuel systems in any two car garage, a chicken in every pot--oops, that's JB McObaiman's line.....

Going to bed on time tonight, y'all have at it.

Andy-Paul