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Let's burn more sunshine 4

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fast4door

Mechanical
May 29, 2012
39
Climate change deniers, go away.

So let's say global warming is caused by pulling tightly-packed carbon out of the ground in solid/liquid form, then combining it with oxygen and creating more CO2 than there was previously. Let's also say we want to simply freeze the amount of CO2 in the atmosphere and dispense with this "sequestration" baloney. In that scenario, we would need a carbon-neutral course of energy. That leaves nuclear or solar or bio-fuels. I want to talk about bio-fuels.

Here's what I can't figure out. Nature has been capturing sunlight and turning it into carbohydrates and lipids for like a trillion years. There's tons of energy out there. We're really good at disassembling those hydrocarbon chains inside of cylinders, turbines, etc. We should be able get good old nature to make our fuel for us. Is there any hope to the people that want to make biodiesel from algae? Are the yields unrealistically low?
 
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I have a more pragmatic take on the politics. If politicians create a carbon tax, any reduction here will be overtaken by 2 dozen power plants going up in China. Any future technology has to be inherently cheaper than fossil fuels (without subsidy) or the market won't accept it. I'd love to see an all-electric economy powered by nuclear that's cheaper than current rates. If you are convinced CO2 is driving global warming a market-driven solution is the only thing that will work globally.
 
I guess we could get pretty brutal on what we consider core food/agricultural production.

Tobacco definitely out, and possibly over products that get smoked, that should save a few acres.

Things like tea, coffee, cocoa, hops, agave, wine grapes ... aren't really staples or even key to healthy balanced diets these days are they (assuming we can keep our water drinkable by other means)?

On fruit and veg, those with the best levels of calorific content, or other key nutrients that are also robust enough to minimize losses during distribution (or suitable for freezing or other preservation methods) could be prioritized - taking into account what climatic zones and soil types are most suited to these crops V simple bio mass.

Pastoral farming could be massively reduced, certainly the livestock that get fed agricultural products rather than just grazing on land not well suited to traditional agriculture. Of course it may be that some of the non prim land may be suitable for some kind of biomass crop so soy curd all around everyone.

So there you go, without even increasing the amount of land devoted to food production/growing stuff how much biomass do those changes generate.

Now we just nee the one world government to over see it...

Posting guidelines faq731-376 (probably not aimed specifically at you)
What is Engineering anyway: faq1088-1484
 
Kenat, you're over thinking it. Soylent green.
 
fast4door,
Remember Soylent green. is people.
B.E.

The good engineer does not need to memorize every formula; he just needs to know where he can find them when he needs them. Old professor
 
There are lots of promising avenues for cleaner energy that the US won't have to import (personally, I'm rooting for fusion sometime in the next 50 years), but I can't get over the feeling that conservation is really all we need. We've still got people driving cars that get <20 MPG, 4 MPG semis are still the method of choice to move product, jiggawatts (yes jiggawatts) of fossil fuel power are used to cool leaky houses in the summer and heat the same houses in the winter.

If we cut energy consumption by half, we wouldn't need oil anymore. We'd still have to deal with switching over transportation to new energy, but at least that'd be a viable course.

"Engineers like to solve problems. If there are no problems handily available, they will create their own problems." -Scott Adams
 
Yes, that is a good point. You save more fuel by getting the guys in 15 mpg gasoline trucks into 30 mpg diesel light trucks, then by getting the 30 mpg gasoline dudes into 60 mpg hybrids.


Cheers

Greg Locock


New here? Try reading these, they might help FAQ731-376
 
Greg, your example works, but don't forget that diesel has a noticeably higher energy density (per gallon) than gasoline. It's all in how they crack the crude.

And I know not everywhere is Austin - they're hot for "zero waste" here, minimizing the yard waste which goes in the landfill is part of it. Probably depressed my numbers, but I figured it's the state capitol and I may as well use it. :)
 
Yo, KENAT, lay off the tobacco and coffee OK? How am I supposed to get thru a work day:)
 
EngineerErrant, take a look at this:


For those who won't read it, as we increase efficiency in, say light bulbs, people tend to just use more light bulbs to light their house, partially erasing the efficiency gains.

The other problem is humans use X energy today. As living standards increase, people in other countries will grow far more in their energy consumption than we can save in going from 30 to 35 mpg.

I truly believe efficiency gains alone won't solve the problem. As a professor once told me, the efficiency of gas engines is getting better linearly, but the number of engines on the planet is growing exponentially.

I'm not saying we should burn barrels of oil in our backyards just 'cause, but I'm not going to significantly curtail my driving, for instance, just because of eco-guilt. Will I turn off lights and combine errands? Yes.

The solution is cheap energy that's carbon neutral. And as I wrote above, there's not enough solar energy hitting the earth to make any kind of renewable realistic.
 
It strikes me that your argument is basically: "People's psychology can erode the effects of conservation in some fashion, so screw conservation." The article you cited estimates rebound effects at just 30% of the drop from efficiency. Also, this line from the article is somewhat telling of the author's attitude:

Ronald Bailey said:
The upshot is that energy efficiency mandates advocated by environmental activists with the aim of mitigating future man-made global warming will likely fall far short of their goals.

Yeah, good thing that these plans to reduce carbon emissions won't work; we'd hate to see those smug environmental activists gloating over making the world a better place.

I'm not saying doubling the efficiency of everything will halve the emissions, I'm saying halving consumption will halve emissions. Grossly energy inefficient transportation is just an obvious target; if all it takes is enough economic, moral, or social pressure on people who, for example, refuse to curtail their driving just due to "eco-guilt," that might be enough.

"Engineers like to solve problems. If there are no problems handily available, they will create their own problems." -Scott Adams
 
fast4door, you tell climate change doubters to go away in your OP, then say you aren't going to significantly change your behavior because of Eco-guilt.

Seems a little inconsistent.

"The solution is cheap energy that's carbon neutral."

While we wait for that nirvana though, perhaps doing what we can with known technology etc. to reduce energy consumption makes a lot of sense. Heck even for hardcore AGW doubters there are lots of other reasons to justify reducing many uses of fossil fuels be it environmental factors more directly tied into health, or balance of payments, national security...

Posting guidelines faq731-376 (probably not aimed specifically at you)
What is Engineering anyway: faq1088-1484
 
I have to think it would be a very poor engineer who is not in favor of what ever efficiency gains can be practically & economically made.

Regards,

Mike

 
as i understand it, the advantage of bio-fuels is that they are recycling C in the short term (ie the C they liberate was only recently taken from the atmosphere) so they are "Carbon neutral". i have a personal dislike for schemes that convert food stocks into fuel.

like greg, i doubt the contribution that man is makig to the climate, but politics is politics. we're now getting a bunch of taxes based on C so we'll see a bunch of counters (C neutral schemes, like bio-fuel, like geo-thermal) ... at the end of the day, we'll all be paying for it, and a small group'll get rich out of it (and i doubt if the planet will notice).

like EE, i think fusion is the long term solution. an initial step might be to develop an electric economy (encourage/push the developing/expanding economies, china/india/brazil, this way rather than burning more and more carbon-based fuels. yes, i know this "merely" more the C burning from millions of small engines to hundred of large power-stations, but it lays the ground for other forms of electric power. like some of the new (and untried) fission designs (pebble reactors for example). and, in the fullness of time, fusion.
 
I have to agree that what engineer isen't interested in gains in practically & economically. It's not just that we conserve energy, which should happen as we improve technology, but we also look at what we throw away. We also need to look to expand our fuel choices, and what sticks will be the ones that are easy to process, and are most cost effective.

Said another way, I don't recycle because it costs me more to do so. The only thing that I can recycle and come close to making my money back is aluminum cans, and my car. And I am not going to reclcle my car while I am still using it.

We could do the world a favor if we lifted our sugar import restrictions, and used it to make ethonol. Or even the byproduct of molasis. If the international price of sugar were to rise, then many farmers could afford a better life style.

Sugar beets is a good idea, even better if we grew them on land that we pay farmers to not grow crops on.

FYI, dead trees can be used in power plants.
 
Beets are incredibly depleting to the soil. Here in southwest Minnesota, home to one of the largest beet cooperatives (and therefore, lobby) it is well known how detrimental to the land it is raising sugar beets. I'll vote for a small efficient diesel any day of the week.

It is better to have enough ideas for some of them to be wrong, than to be always right by having no ideas at all.
 
A bit of clarification on why I won't change my behavior from ecoguilt.

I have 2 examples in mind: cars and CFLs.

CFLs suck. They don't last as long as they claim to because of shoddy quality control and - shocker! - people use them in ways the manufacturer didn't intend, such as ballast-up. Or in humid environments. Or in high temp locations such as can fixtures. Also, take a look at this: If you break one in your house you're supposed to treat it as a mercury spill. I have little kids!! So I'm not going to use them to change my habits because the technology sucks.

Regarding cars, I commute 20 miles to work. It takes around 35 minutes. I've researched busses: the best route takes 2 hours. My car is paid for and gets around 25 mpg. I need 4 doors for aforementioned kids, and I ain't driving a civic because I'm over 6 feet. For me to put a significant dent in my car's carbon footprint would require a large sacrifice of convenience and/or money. So I'm not changing.

My overall point is you have to accommodate people's expectations. Any solutions have to fit into people's lifestyles without big adjustments.
 
yes, but in the name of progress you will be Made to change ...

politics is politics, and has a habit of creating the world in it's image (that is untill the real world takes over and spins the dream into fairy dust). for example, deregulation of the power industry (Enron), of the financial industry (WFC pt 1).

deregulation of the power inductry (in the US) was intended to provide cheaper power. i think it did initially, but then free enterprise took over and the linkage between action and consequence was broken and you ended up with black outs and a few people making bags of money (and fewer people going to jail over it).

i think this "Carbon is evil" mantra will run the same course. the government will (acting on our wishes, expressed as our votes, and/or acting on the best advice available, from focus groups, special interest groups, and assorted nut-jobs and/or crooks) tax carbon (like Australia is now) which will have a generally negative effect on the economy, and make a very few very rich, and will IMVHO) have just about zip all effect on climate change.

 
fast4door, "CFLs suck", all the hotels I have stayed in recently have CFL's in each fixture. I find that if I turn on EVERY ONE IN THE ROOM and wait a little while for them to warm up, I can get some halfway decent light:)

"Energy saving"? I doubt it.

Regards,

Mike
 
Cheap CFLs do suck. Decent CFLs come on quickly and have good color. They also have a very tiny amount of mercury (under 2 micrograms)

Early and current CHEAP CFLs do have the problems described above. Get decent bulbs (and I'm still talking less than $2/bulb at Costco or something) - and these are all solved issues.
 
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