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Let's burn more sunshine
4

Let's burn more sunshine

Let's burn more sunshine

(OP)
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?

RE: Let's burn more sunshine

My brother in-law is doing PhD research at a well known university on utilizing photosynthesis to create alternative energy. All I can say is its not simple.

RE: Let's burn more sunshine

Biodiesel is plausible enough that there are now ASTM standards for it.

Algae biodiesel looks plausible, if they can keep the algae from clogging their mechanism, and low-oil competitor species from invading the growing media. Soy biodiesel is plausible, but uses food crop land. Jatropha can be grown for biodiesel oil in areas unsuitable for food crops (though with lower yield.)

Waste vegetable oil -> biodiesel makes sense at an individual/backyard/small co-op level, but there's not enough available to make a meaningful impact at city level, let alone nationally.

Ethanol makes sense in the tropics with sugar cane -> ethanol. Corn-> ethanol is little better than breakeven energy-wise. Subsidies make it profitable.

What would be really useful is a practical cellulose -> ethanol route. There are some promising studies and pilots. Lots of inedible waste cellulose - for example, the rice hulls which are burnt off every year. Grass clippings. Corn stalks.

RE: Let's burn more sunshine

How about instead of Corn Ethanol something crazy like 'Beat Ethanol' for places that can't grow sugarcane?

However, back the OP... In principle algae bred or GM'd to have higher oil/fat seems interesting. The devil seems to be in the detail as TomDOT mentions.

I won't get into the usual discussions about whether bio fuel => liguid fuel really makes much sense on a large scales, or if we'd be better using simple biomass for stationary power generation and divert the saved fossil fuels (even NG) to mobile applications.

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RE: Let's burn more sunshine

Boatloads of excess NG being produced in the USA at the moment. Unfortunately, we don't yet have enough facilities to go from NG to LNG so that we can actually load it on the boats.... Check back in 5 years.

I don't know whether beets--> ethanol would be reasonable. We only have beet sugar at its current production level because of HUGE tariffs on imported sugar. World sugar prices are much lower than US sugar prices.

RE: Let's burn more sunshine

(OP)
What if, instead of trying to force nature to give us a uniform liquid we can inject into our cylinders, we just burn the cellulose we have? Grain elevators explode all the time because of suspended flour dust. Steam engines did this: they could be run on anything that burned. The problem was that it was an external combustion engine which is inherently less efficient than an internal combustion engine. Plus I think diesels really killed them because they didn't have to heat up a monstrous tank of water in order to get going.

So two alternatives: could we internally combust solids? Or, could we burn plant matter and generate electricity and have an all-electric economy?

One idea I had to get around the problem of long charging times was to have swappable battery modules at filling stations, much like the propane tanks outside gas stations. Each battery would be the size of a suitcase (or whatever didn't weigh too much), and you could swap out 5 modules or so when you go to "fill up".

You're welcome, car companies. I'll expect my royalty checks any day now.

RE: Let's burn more sunshine

(OP)
Tom, my heating bill has gone down by half over the last few years. I'm very thankful, but that is still carbon we're adding to the atmosphere. It's better energy per carbon emitted than coal or oil, but it's still adding.

RE: Let's burn more sunshine

fast4door - exchangeable battery packs aren't a novel idea. They've been discusses on one of the previous 'global warming' or 'green engineering' threads before. In fact I think Greg Locock may have even directed us to some industry paper or similar on it.

Plus, I though my comment about burning biomass for stationary power generation pretty much covers your post about burning cellulose.

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RE: Let's burn more sunshine

(OP)
KENAT, sorry, I didn't fully understand the implications of stationary power generation in your comment. So the reason we don't burn plants instead of coal is because coal is cheaper, right? Is that actually a true statement or do we just default to coal because it's more convenient (consistency, existing infrastructure, etc)?

Could engines be adapted to burn airesolized dust? What if I put 5 pound bags of flour in my fuel tank (yeah, okay, not acutally wheat, but powdered cellulose or something) and instead of fuel injectors we would have something like a carburator that uses high-velocity air to pick up dust to put it into the cylinder? If you controlled the fuel/air ratio you would minimize ash, right?

And just think: everybody's car would smell like the outside of a bakery!

RE: Let's burn more sunshine

Well the fundamental problem with ANY bio-energy scheme is that....it's solar energy. So here in the middle US you're getting a year-round average of about 200 W/m^2 incident energy, if I remember correctly. To really scale up to replace most of the fossil fuels requires an area on the order of the entire US just to produce our transporation fuels. No food, no fibers, no flowers, etc.

Yes, some technologies are better than others, some have higher conversion efficiencies, and so on.

But the incident energy, the source of it all, is not very intense.

Regards,

Mike

RE: Let's burn more sunshine

In the late middle ages in Europe my understanding is they started running out of suitable biomass for fuel use, and this may have been part of the reason for colonization of the new world etc. Similar has happened in other places leading to deforestation etc.

Ok, we have better technology now (not just on the combustion side but in agriculture etc.) but we also have higher population (so as well as more people needing energy, more demand on land resources for other use such as growing food or timber for housing) and higher energy demands for the current western lifestyle.

So it doesn't look overly promising for bio fuel to become the primary energy source any time soon.

Sure, we can make biomass production more efficient, make more use of different types of biomass, find ways to increase the amount of land available for generating biomass, better ways to turn biomass in to more readily usable energy...

Coal, by several definitions, is a more dense energy source than most biomass and I'd guess more consistent. May be easier to work with too than some biomass.

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RE: Let's burn more sunshine

(OP)
Way to go Mike. You've just depressed the living heck out of me. I found another source, http://zebu.uoregon.edu/disted/ph162/l4.html, that concurs with you. Basically there's not enough solar energy reaching the surface to keep up with our energy needs.

Sigh.

So that leaves nuclear, right? Unless we can generate enough extra energy to sequester the carbon we produce. Or if nature reaches a new carbon consumption equilibrium to keep up with our production.

How's Gates's thorium reactor coming? Have the Chinese started any pilot projects yet?

RE: Let's burn more sunshine

SnTMan - it's not nearly that bad for biofuels if we get cellulose in the game. I did a BoE calculation* awhile back. With an efficient cellulose -> liquid fuel method, a city could produce 10% of its transportation fuel purely form yard waste which is currently being landfilled. I didn't even count construction debris, or agricultural material which is currently being wasted (like the aforementioned rice waste burnoff.)

For incident energy, kWhr/m2-day is a more useful unit. Austin, TX gets roughly 4 kWhr/m2-day of solar energy on an average day (DNI). El Paso gets 7. Abilene gets 5-6.

*Using hard numbers for population, average fuel consumption, mass of waste going to the landfill, percent of waste as yard trimmings, etc. Austin, TX was my example calculation.

RE: Let's burn more sunshine

(OP)
Tom, I don't disagree with your numbers, but you can't capture ALL of the ground level solar power. You need big big chunks of it just to power things like "all the plants on earth" and "weather". Both of which we are already messing with.

Mr. Fusion it is.

RE: Let's burn more sunshine

TomDOT, well the numbers can be done somewhat differently based on assumptions and so forth, but still, incident solar energy limits any really large scale replacement of fossil transportation fuels with bio-fuels. Everyplace ain't Austin:)

Regards,

Mike

RE: Let's burn more sunshine

fast4door, I believe gas turbines can be run on coal dust.

RE: Let's burn more sunshine

There are other options besides Nuclear.

Any individual one may not be able to replace all fossil fuels, and have pro's and cons, and many may be of dubious overall efficiency and many of them are indirect solar engerby but there are lots of them.

Geothermal is one that seems a bit underutilized.

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RE: Let's burn more sunshine

Bio-fuels just seems like grass-roots solar energy to me.

RE: Let's burn more sunshine

First, Better Place are building automated battery swapping stations for suitable electric vehicles. Having long been a proponent of that technology, I am a bit more dubious now that push has come to shove. The battery swap station either needs a lot of power, or a series of large trucks taking empty batteries to somewhere where there is a lot of power.

Secondly, I strongly recommend your read "Without Hot Air" as the author does a reasonable job of presenting the options in a sensible fashion. It is a full book, but is free.

Thirdly I am a CC sceptic, that is, I strongly doubt reducing CO2 produced by man will have much effect on the climate, and don't believe the /science/ (as in stuff that follows the scientific method as opposed to silly statistical curve fitting) has progressed much beyond Arhenius in the last 30 years. But I have no objection to increasing efficiency, and exploring alternatives to oil seems wise. At the same time displacing food crops with fuel crops seems unethical to me.

Cheers

Greg Locock


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RE: Let's burn more sunshine

(OP)
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.

RE: Let's burn more sunshine

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...

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RE: Let's burn more sunshine

(OP)
Kenat, you're over thinking it. Soylent green.

RE: Let's burn more sunshine

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

RE: Let's burn more sunshine

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

RE: Let's burn more sunshine

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. :)

RE: Let's burn more sunshine

Yo, KENAT, lay off the tobacco and coffee OK? How am I supposed to get thru a work day:)

RE: Let's burn more sunshine

(OP)
EngineerErrant, take a look at this:

http://reason.com/archives/2012/07/17/the-paradox-...

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.

RE: Let's burn more sunshine

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:

Quote (Ronald Bailey)

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

RE: Let's burn more sunshine

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...

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RE: Let's burn more sunshine

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

RE: Let's burn more sunshine

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.

RE: Let's burn more sunshine

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.

RE: Let's burn more sunshine

Regarding beets: http://cnas.tamu.edu/ConfPresentations/Papers/Thei...

Looks like it's feasible, although I share most posters' distaste for burning food.

"Engineers like to solve problems. If there are no problems handily available, they will create their own problems." -Scott Adams

RE: Let's burn more sunshine

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.

RE: Let's burn more sunshine

(OP)
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: http://epa.gov/cfl/cflcleanup.html. 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.

RE: Let's burn more sunshine

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.

RE: Let's burn more sunshine

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

RE: Let's burn more sunshine

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.

RE: Let's burn more sunshine

Quote (TomDot)

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.

Exactly. For some reason with CFLs, people mysteriously forget that cost usually correlates pretty well to quality. They buy the cheapest brand of CFL they see, then when it doesn't work well criticize the entire technology, instead of just that brand.

Pay the extra 50 cents for a quality brand, you will get a quality product.

And if your electricity comes from coal, it will result in far less mercury going into the environment.

RE: Let's burn more sunshine

Quote (KENAT)

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.

I realize this sounds like something out of an Isaac Asimov story, but what if we had an entire planet of acceptable land for biofuel production? Say, Mars?

http://science.nasa.gov/science-news/science-at-na...

http://www.nasa.gov/centers/goddard/news/topstory/...

http://www.popsci.com/science/article/2010-08/mart...

Just a fun thought :)

-Ian

"All models are wrong, but some are usefull" - George E. P. Box

RE: Let's burn more sunshine

Shipping costs are going to have to come down bigtime:)

RE: Let's burn more sunshine

As far as depleating the soil, as in sugar beets, what is the difference between them and other crops? They all will deplete the soil if you don't add something back. Sure it's cheeper, and easer to use chemical fertlizers, but that is the problem with farming today. The rebuilding of the soils after a crop needs to include all the elements taken from it, not just N-P-K. That was the purpose of a manure spreaders was to add an organic mostly complete fertlizer back into the soil.

Now given that Minnesota is not well known for livestock, there maybe a local shortage of manure. This can be a problem. Another problem is that crop rotation isen't used anymore. Most backyard gardeners will tell you it is important, but big farmers don't do it.

As far as CFL's, I've had more problems with LED's failing, or the glue used just gives way. But then again most of my CFL's I got for free from the local electric company.

RE: Let's burn more sunshine

cranky,

Legumes (beans, soybeans, clover) are the obvious counterexample. They will increase the nitrogen in the soil - they have a symbiotic relationship with some microbes, and "fix" nitrogen from the air.

Different crops have different effects on the soil. This is why "crop rotation" was born. Instead of having a field dedicated to corn, you would plant beans one year, corn the next and perhaps alfalfa for your livestock the next. The next field over could have the same rotation, but start on corn.

RE: Let's burn more sunshine

why are we talking about the Canadian Football League ?

RE: Let's burn more sunshine

Wasn't the subject poor substitutes for the real thing? KIDDING:)

Note to Admin: Would you please, please quit improving things?

Regards,

Mike

RE: Let's burn more sunshine

Zing !

RE: Let's burn more sunshine

Minnesota "Now given that Minnesota is not well known for livestock"? come on, have you ever been there? And "crop rotation isn't used anymore..." thats just hogwash

RE: Let's burn more sunshine

Regarding nuclear fission, the number 1 major accident / 10,000 years of operation seems to be thrown around quite a bit in pro-nuclear literature. Sounds like a reasonable number, with our 500 some odd nuclear reactors in operation worldwide that would be once every 20 years. If nuclear suddenly went from 5% of global power to 50% or more using current technology would people really be able to stomach a Chernobyl or Fukushima level event every other year?

Comprehension is not understanding. Understanding is not wisdom. And it is wisdom that gives us the ability to apply what we know, to our real world situations

RE: Let's burn more sunshine

Beet processing is an incredibly stinky process. Drive thru Ft Morgan Colorado any time of the day or night. A feedlot with 10,000 cattle would be an improvement. The beet trucks can't seem to keep the beets in the truck, so all the roads around there are like driving on grease during harvest.

I haven't seen natural gas-powered fuel cells mentioned? They appear to combine a widely distributed, cheap, fuel with a technology that is very scalable, and a conversion process that produces ~60% lower C emissions. An important consideration is that distribution losses of an electrical grid is eliminated (but yes, gas has to be pressurized to flow).

RE: Let's burn more sunshine

i think there are "better" fission reactor designs. the problem is we've got some experience with the pressurised reactors we have today (good and bad experience ! ... you learn more form the bad experiences, unfortunately) but no experience with the un-tried designs. so no matter what they promise, it's hard to back them with no real world experience to draw on.

RE: Let's burn more sunshine

There are also less risky (with 20/20 hindsight) locations for reactors.

- Steve

RE: Let's burn more sunshine

http://www.withouthotair.com/

Don't talk about the potential from non-fossil energy sources until you've read this book.  He even does calcs on how long our uranium, thorium and seaborne uranium and thorium would last.

Without nuclear and without fossil fuels, there isn't going to be a future without some MAJOR adjustments to how people use energy, i.e. how and where they live, what they consume, how they get around, and how many of us there are.

Biofuels, geothermal, solar and wind are all partial solutions, with benefits and consequences depending on what you use them for and how you deploy them.

Take it from someone in the business:  making liquid transport fuels from non-food biomass is a tricky, expensive business.  It's way easier to dig or pump fossil carbon from the subsurface, refine it and use it.  The most efficient way to use nonfood biomass to generate energy is to burn it to make low-grade comfort heat or to make electricity.  On an energy returned per unt energy invested basis, you can only transport that bulky biomass a certain distance before you get less out of it than you invested to harvest and transport it.

Note also that intensive agriculture (i.e. what is used for food production) is not sustainable in most places at current yields without a hell of a lot of fossil fuel-derived fertilizer.

People don't make major changes to how they live unless they're forced to, and then they do it reluctantly.  Even making them pay more doesn't do it very well. There is tremendous elasticity in the energy use supply/demand equation.

The only thing which works less effectively at reducing energy consumption than making people pay more for the energy they use, is NOT making them pay for it.

Until there's a cost to dumping bad things into the atmosphere, people will prefer to dump sh*t into the atmosphere because it's cheap and convenient to do so.  You can't run an energy industry entirely on government subsidy.

Fortunately, frac'ing has generated a bumper crop of natural gas in North America, allowing us to leave more of the worst fossil carbon (coal, tar sand and oil shale) in the ground for a while longer- if we choose to.  However, the cheap NG makes it cheaper to exploit tar sand too, and the differential in price between oil and gas promotes what I consider to be energetically wasteful technologies such as SAGD for tar sand and Fischer-Tropsch conversion of natural gas.  As the easier sources of liquids become scarcer and hence more expensive, carbon intensity to recover those fuels will inevitably increase.

RE: Let's burn more sunshine

Eh, being willing to use fast breeder reactors increases effective uranium by about 100x, since we will use all of it instead of just the (<1%) U235. Thorium is even more prevalent than uranium. Reprocessing "spent" fuel increases energy further. Plenty of energy to provide 100% of world electricity for centuries.

On the engineering side, nuclear is a solved problem. Social/political/cost issues remain. Cost is driven in large part by the social and political issues.

As you noted, non-food biomass is not really a solved problem - at least not at a useful scale.

RE: Let's burn more sunshine

TomDOT, while nitrogen fixation is important in crop rotation, but it dosen't fix other soil deplations. Which is the point of using bio derived fertlizers. Many farmers don't even use crop rotation, just add factory made stuff.

I can get behind green, if you can tell me what is green and non-objectionable. That's my objection to nucular, wind, biomass, etc. It's not the concept, it's the attitude that we have to fight anything we disagree with. And suprise someone always disagrees.
Fix the attitude, that some times we need to accept something we disagree with for the greater good. Make things positive, by not being negitive to everything.

RE: Let's burn more sunshine

I agree, "Hot Air" should be required reading. Another book I really liked (you'll have to buy it unfortunately) it "The Solar Fraud". Rhetoric is a little pointed at times, but the physics is dead on.

Regards,

Mike

RE: Let's burn more sunshine

(OP)
Correction!!

This source: http://zebu.uoregon.edu/disted/ph162/l4.html is wrong by 3 orders of magnitude in the amount of solar energy hitting the earth. I had said earlier that there wasn't enough solar to replace the amount of energy we need on a daily basis; that is now completely wrong. There's craptons of solar, if we can just harness it.

The issue, as pointed out earlier, us that if you're using farmable land to produce biofuels, we can't eat. So I'll ask again: someone tell me what's going on with algae? Theoretical outputs are way higher than soy or corn, so what's the holdup? How can it be so hard to grow? I'm sitting next to a pond full of the stuff right now - are wetlands going to end up being outrageously economically productive?

And come on - if the Native Americans could take grass and domesticate it into corn, what the heck is our problem? We can sequence genomes and splice anything we want in there!

RE: Let's burn more sunshine

GM algae for fuel. THe envirenmentalists would have a field day with that! Can't wait.

- Steve

RE: Let's burn more sunshine

The main problems with algae are:

1) Scaling. It's proven at lab scale, someone was going to do a pilot scale. Nobody has it at industrial scale

2) Contamination/infestation. To be effective, you have to grow a high-oil species. If you get a single cell of a more competitive low-oil species, it can totally outgrow/swamp out your desired species.

Are these problems which can be overcome? Sure. Just not today or tomorrow. Big learning curve to climb.

And yes, there is a crapton of solar insolation available. I wish that people would do more "smart" microsolar. For example: Instead of building a carport/RV/patio roof and putting solar panels on that roof, use the solar panels AS the roofing/shading material. Double usage, reduced cost, multiple benefits.

Specific example: Wal-Mart has roughly 100,000 acres of parking lots in the USA, all of which are adjacent to a heavy-duty connection to the grid (for the store) meaning that infrastructure and transmission investment would be minimal. Wal-Mart could provide shaded parking as a benefit to customers (saving on AC demand in their cars) and at the same time produce a crapton of electricity.

Back of the envelope: Figure a conservative 5 kWh per square meter solar insolation, giving roughly 20 MWh per acre. Multiply by acreage to get 2 TWh solar insolation. Figure 10% areal conversion efficiency for both spacing losses and panel efficiency. So, 200 GWh available from Wal-Mart parking lots every day.

2011, the USA used 3,856 TWh of electricity, giving a daily average of 10.56 TWh. So, we could get about 2% of the US electric demand supplied from solar panels in Wal-Mart parking lots alone. As a bonus, it's mostly peak demand electricity - both daily peak, and annual peak. (I actually ran this calculation from a second set of base assumptions ending up with 2.4%, chose the more conservative result above)

Now consider how many more parking lots there are than just Wal-Mart.

RE: Let's burn more sunshine

(OP)
Just to be clear, a crapton is 1,000 petatons.

RE: Let's burn more sunshine

1) Walmart doesn't need covered parking. The stores are already packed out
2) Only the projects installed in the sunbelt region will be profitable
3) structural supports, DC to AC converters, transformers, cable and J-boxes and switched connection to the grid are still required. This is the bulk of the expensive infrastructure. In fact, the carport type structure would make it much more expensive than a typical solar farm with pier foundations.
4) walmart parking lots really aren't that large compared to commercial scale solar farms
5) Even with the taxpayer subsidies, the ROI is only marginally attractive

RE: Let's burn more sunshine

Mind if we use watt-hours? It actually can be made to work out.

5x10^14 square meters of earth's surface, 6kWh/square meter/day (average global solar energy. I used 5 above for the USA)

3.0x10^18 watt-hours/day. Divide by 10^15 for Peta.

3000 Petawatt-hours/day.

Let's allow 2/3 of the surface area as too difficult for current engineering (deep ocean)

1000 Petawatt-hours/day.

Done. One crapton of solar insolation per day.

RE: Let's burn more sunshine

cvg:

1) Opinion only.
2) It was an example of the energy available, not practical site selection.
3) Apparently you are unaware of the billions of dollars Texas is spending for new and upgraded transmission lines to handle a measly 10 GW (nameplate) of wind power. Also, don't be silly. The home carport and Wal-mart parking lot were two separate examples. You would optimize the structure in the parking lot, some additional cost to make sure it is high enough for cars to pass under cleanly.
4) Yep, it was an example of the energy available, using a scale familiar to virtually everyone here. It is also an example of multiple beneficial uses of the same property.
5) Ditto.

RE: Let's burn more sunshine

TomDOT, is your 10% allowing for the fact that much of the parking lot is actually road way so maybe half the total parking lot area could realistically be used for solar panel car ports. I assume so but wanted to check.

As for Algae, there are a lot of problems with how to get the necessary light to all the algae - you end up needing a large effective surface area. Plus the algae like to stick to surfaces so simply using thin transparent pipes or chambers with lots of internal mirrors... get's tricky.

Plus there may be temperature limitations on the algae, and just the amount of water required might get to be an issue.

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RE: Let's burn more sunshine

(OP)
Does anybody know of a technique where solar is converted directly to chemical energy, just like plants? The problem with solar is the ROI sucks because the efficiency isn't good and the silicon is expensive. Can't we just convince some plant species to spit out sugar or something and then burn that? Like a maple tree, only less good on pancakes and more good in cylinders.

I saw something on This Old House a couple seasons ago that used a solar panel to generate current that was used to denature water, which was then stored in gas tanks to be recombined in a fuel cell. It solves the peak issue, but the problem again is the capex is huge due to the silicon and the platinum catalyst.

RE: Let's burn more sunshine

KENAT - as cvg mentioned, the "car port" design is sub-optimal for a real parking lot installation. "Car port" was more for a home car port/RV shade.

Panels for the parking lot can readily extend over the driving areas. Shade would be somewhat compromised by optimizing for electricity production, but shade is just a side benefit anyway.

RE: Let's burn more sunshine

fast4door - the silicon problem has largely been solved by the thin film PV guys. They use ~1% of the silicon you would find in a traditional PV panel. Efficiency was a problem at first, but they're over 14% now and still climbing.

RE: Let's burn more sunshine

(OP)
Okay, so 14%. That still seems low. But only because I'm thinking of a diesel engine which gets something like 30%. But maybe I'm off-base? The fact that we can see leaves on trees (and the fact they appear green) is evidence they're not capturing 100% of the light hitting them. Does anybody have an idea what the efficiency of a leaf is?

RE: Let's burn more sunshine

TomDOT: The idea of dual- purpose roofing/solar collectors isn't new but isn't an economic reality yet either.

I assume you're joking, but naive calcs like the ones you just did are the reason that David MacKay wrote his "Alterative Energy Without the Hot Air" book. Have a look at his estimates for solar and compare against yours. His estimates are limit-state estimates, assuming money is no object. He looks at both solar thermal and solar photovoltaic, along with various biofuel options.

FYI, a Sharp 235 W polycrystalline panel measures 0.99m x 1.64 m or about 1.62 m2

http://files.sharpusa.com/Downloads/Solar/Products...

A Toronto, Ontario solar installation can be expected to generate about 1175 kWh/yr per kW of panel nameplate capacity if installed at the optimal angle.

http://www.greentoronto.me/evaluating-solar-power-...

People in Ontario are willing to cough up the necessary capital to install such systems in return for the $0.60-$0.80/kWh feed-in tarrif that the government will pay them for power from a solar installation, but at $0.10/kWh, none would be built by anyone who cares about their money and can do math. You can calculate a break-even tipping cost for CO2 emissions on that basis if you like- it's pretty steep.

Algae to biodiesel? Again, at best a partial solution, with lots of technical obstacles that translate directly into economic obstacles. The only good thing I can say about algae are that most people wouldn't consider it to be food biomass, although "single cell protein" of various sorts has been pitched as an animal feed additive for many years. In terms of algae to biodiesel, just the cost to cover the required land area with glass or plastic containment structures resistant to weather throughout the year is going to be prohibitive, and open ponds give sharply limited productivity. The bugs don't make much use of increased light intensity, so there goes the plan to replace most of that glass with cheaper reflectors. Green plants solve this problem by growing their own support structures so they can make more use of the available insolation, but that comes with losses as well.

RE: Let's burn more sunshine


here's a good example, $17k capex per parking spot

https://cfo.asu.edu/solar-installations

Stadium Drive Parking Structure (PS 5) (provides 361 shaded parking spaces on top deck)

Max. Generating Capacity: 711 kWdc
Est. Annual Production year 1: 1,386,060 kWh
Actual Annual Production: 1,429,057 kWh
Capacity Factor: 28.68%
Commissioned Date: 12/2008
Number of Panels: 3510
Panel Size: 200/210 watts
Panel Type: Polycrystalline
Panel Manufacturer: Suntech
System Type: Single-Axis Tracker
System Installer: CarbonFree Technology
System Owner: Sun Devil Solar, LLC
Contract Type: Power Purchase/Qualified Management Agreement
REC Incentive: $0.25/kWh (APS)
Total Project Cost: $6,104,824

RE: Let's burn more sunshine

Oh, I agree that these structures aren't really practical yet (particularly as far north as Ontario!) Solar combination projects are effectively one-off "demo" projects at this point and nowhere near cost-effective.

And yes, the "crapton" calculation was joking, if cost were no object.

If you can point out a flaw or refinement in the Wal-Mart calculations, please go ahead. Obviously they were ballpark numbers. Commercial crystalline PV panels at the 18% efficiency level can be readily obtained. The best are more like 21% (unless you go stupidly expensive like the space-rated ones)

RE: Let's burn more sunshine

Somewhere there was a statment that solar energy is at peak electrical usage. This is just wrong. At my location we can only expect about 6 hours of peak sun a day. The sholder hours are around 12% of that. A directional aming unit only add about 15% additional peak sun.
If peak sun is about noon, and is available 3 hours before that and after that, then how is that offset peak electrical usage at 6PM?

Wind has the same issue, it is highest at night.

What needs to be developed is an energy storage system that does much better than 50% losses.

As far as converting sunlight directly to chemical energy, I had these wall stick-ons that would do that, but they kept me up all night.

RE: Let's burn more sunshine

cranky - you're right, PV solar actually leads the peak demand. It's fairly close. Much closer than wind. Of course, since total grid-attached storage is pretty small (a few pumped hydro, one new kinetic facility) "close" doesn't help that much.

Thermal solar can be easily built with short-term storage (molten metal, hours in duration) to perfectly match peak demand. Cost is less attractive since PV prices dropped.

RE: Let's burn more sunshine

I thought a crapton was 1000 fart tonns which was a 1,000,000,000 truckloads.

Seriously I have been involved in two projects to replace existing materials in structures to have a double duty of collecting solar energy to be put to good use. Both failed, in my opinion due to failure to choose optimum design and materials.

One was a roof tile that substituted concrete tiles in sections of the roof of the home. It was a clear plastic and incorporated heating elements for a solar hot water system. It failed because the designer tried to use a fairly way out idea to mould a part in a 600 tonne press that should have been moulded in a 2000 tonne press and because being a toolmaker and used to working to 0.0001" accuracy at times, he completely failed to allow for the variations in dimensions of concrete roof tiles.

The other was a swimming pool fence incorporating a solar hot water system in the fence panels. It should have and still could work. The original material for the fence rails which doubled as manifolds or header tanks failed stagnation tests with chlorinated water inside after extended exposure when the daily maximum hit 40 deg C

An alternate material is chemically suitable but cannot be glued. They bailed out instead of altering the design to barbed socket like a light bulb fitting with O ring seals. I just may have someone else interested in buying the project from them.

Regards
Pat
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RE: Let's burn more sunshine

Tom, it is because of this lead in solar energy that we need to keep existing power production. That we can't replace power plants with solar energy, until we develop more or better energy storage technology or methods.

There's nothing like buying energy for 0.10 $/kWh, and storing it to use latter, so the total cost is 0.15 $/kWh.

RE: Let's burn more sunshine

Yep

Solar to pump water to store at an elevated position, then hydro from that storage pond seems a good realistic system.

Might even double up for irrigation mostly using existing infrastructure if the planners where real smart

Regards
Pat
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RE: Let's burn more sunshine

Why not just use wind at night to fill that pond.

There again, look at how efficent it is. The losses are around 50%, water pumping is not efficent. Motors for pumping are not efficent. Hydro generators are efficent but not perfect. There are losses for evapration, and water flow in the pipe.
So take the expected energy need and use a 1.5 factor and get a better look at the numbers.

The reason pumped hydro is so uncommon is because of the need for height differences. That type of terain dosen't exist everywhere. And because of the cost of not only the plant, and lakes, but the difference in energy costs between day and night aren't great enough to justify the losses.

RE: Let's burn more sunshine

I was thinking along the lines of a small dam downstream of an existing dam. The increased hydro power capacity will drain the existing dam to fast so the water collected down stream could be pumped via solar power.

Regards
Pat
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RE: Let's burn more sunshine

pumped hydro at a commercial scale is very expensive. you need two large reservoirs, pumps, pipeline, makeup water plus a penstock and generator. transmission lines and then the environmental and dam safety permits also. much cheaper for a conventional powerplant

RE: Let's burn more sunshine

from the link, hydro-storage uses more energy than it produces (no surprise there, remember the 2nd Law of thermodynamics ... "you can't break even").

the point is that it smooths out the peak demands and over-supply of power, by producing power in peaks and consuming power in lulls; allowing mainline stations to work steadily at optimum efficiency.

RE: Let's burn more sunshine

... like one of those new-fangled hybrid car things.

- Steve

RE: Let's burn more sunshine

Everytime you propose a new hydro facility, someone complains. Same thing with coal, oil, gas, nucular, and now wind.
The public seems fixacated on solar, however, not the steel production, sand extraction, or other processes it takes to make them.

After the recent fires, you would think someone would be calling for better forrest managment, and burning of trees. Which by the way is a solar to chemical energy, and probally the cheepest renewable energy storage. And it provids lots of jobs, which other renewable energy are magnitudes away.
The problem is harvesting, and transportation. But just as mine-mouth power production has been good for coal, maybe the same can be used for wood.

RE: Let's burn more sunshine

cranky108, people complain about solar as well, at least some of the large facilities planned. They're worried about the habitat loss etc, including from the power lines & access roads etc.

Pat, I've wondered about similar, I always have a feeling that I'm missing something though.

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RE: Let's burn more sunshine

every form of electric power generation uses more energy than produced. there is no 100% efficient conversion technology available. hydropower is useful because the stored energy in the water is replenished naturally and the water is delivered to the penstock by a river, no trucking required. storing the water however takes capex to build and maintain a dam. double that if you plan to pump storage using a second dam. and approving the EIS for a new dam on a perennial stream is about as easy as getting the building permit for a new nuke. so in order to get around that, pumped storage may be built off stream, which makes it even more expensive. A good example of this is Taum Sauk in Missouri, which by the way failed a few years ago causing millions of dollars in damage and environmental impact. This failure has made it even more difficult to get any new pumped storage facilities permitted.

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

RE: Let's burn more sunshine

(OP)
Kenat, you mean people complain like this?

http://www.npr.org/templates/text/s.php?sId=129129...

EVERY solar project in California faces these same hurdles. "Wah, you're killing the tortoises." "Wah, you're ruining the view." And on and on. I'm not saying environmental impact reviews shouldn't be done, but they should be put in the context of trade offs: if we don't build this solar bloc, then maybe a coal plant has to increase production and will kill more animals somewhere else.

And for pete's sake, if we can use eminent domain to favor developers over homeowners in New Jersey, can't we just move the whiny nimbys?

RE: Let's burn more sunshine

Some utilities don't want to use eminent domain, because it looks bad in the press (I agree). But I also question why we need to put solar on empty land, when we have so many parking lots. I mean you get in your car and it's 200 degrees, so you turn on the AC to cool it off as fast as possible. Or you let your car run, while you scrape the ice off the windshield. Just put solar over parking lots are the energy savings that is distributed over the car owners should do you proud. A very good method to reduce the consumption of gas, and make lives easer.

What ever happened to the turban powered car? A great multifueled car that never went into production.

RE: Let's burn more sunshine

(OP)
Cranky, I'm going to cut off the trolls and point out that sometimes it's kind of nice to get sun on your car in the winter. There are certainly pros and cons to your parking lot idea, but I think the larger point of using single-purpose space to become multi-purpose is a good one. Hence, panels on rooftops.

Also, I'm going to assume you meant to ask about a "turbine" powered car. A turban powered car would only get like one mile per Sheikh anyway.

RE: Let's burn more sunshine

(OP)
Our cars are essentially turban powered now, aren't they?

RE: Let's burn more sunshine

first one to mention "pull starts" gets RF'd !?

RE: Let's burn more sunshine

Now now boys.

KENAT, I think you started this by declining to start it. Very devious. I'm proud of you boy.

Opps, there you go, some words have a very different inference in the USA to the rest of the English speaking world as Bert Newton, a very popular and particularly inoffensive talk show host here found out when he referred to Muhammad Ali as the boy during a live interview.

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

The incident is mentioned toward the bottom of the Logies section.

A full clip of the incident and context.

http://www.youtube.com/watch?v=xWKyDGGptA4


Regards
Pat
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RE: Let's burn more sunshine

OK, Turbine powered car. My point is where are the real multifueled cars?

Also wonder why we don't have combined cycle plants in cars?

And explain why some groups want to show off there solar panels? They don't impress me. Sort of reminds me of that movie with all of the billbords on each side of the highway. I'd much rather look at powerlines.

I'm not that keen on solar panels on your roof. I have some for heating water, but dosen't work. Now I need to figgure my economics to get it fixed, removed, or other. Since I may need new shingles in a few years, I might have to remove the panels anyway. And with no tax incentive to repair the panels/system, I think I can remove them for a few years, then have a new system installed and get tax incentives.

Which leads my noticing that we are becoming more a throw-a-way society again (we never stoped, but paused for some years).



RE: Let's burn more sunshine

Turbine powered cars? Power to weight isn't really an issue for a ground vehicle, whereas efficiency is. Didn't the Rover turbine cars of the 50's/60's have dreadful lag and general driveability.

- Steve

RE: Let's burn more sunshine

Response lag, cost, exhaust temperature - and parts whirling at 40,000+ RPM. Some failure modes due to impact would certainly be.... exciting.

RE: Let's burn more sunshine

As dumb as this sounds, there are gas turbines that operate at 3600 rpm. So what's the advantage of the higher speed?
What's the exaust tempeture of an otto cycle engine?

If efficency was the important factor, then why aren't we using 2 cycle engines? They should have twice the power output for the same mass.

As far as that goes why did VW get away from the air cooled engines?

The understanding I see is we want a vehicle that is efficent, polution free, and is inexpencive. You can't have all three so it was decided that price will be ignored. The problem with that thinking is, people not being able to afford a newer vehicle, will keep older vehicles alive, which defetes the gains you are hopeing for.

RE: Let's burn more sunshine

One word cranky: "legs"

- Steve

RE: Let's burn more sunshine

The M1 Abrams has a gas turbine, and is very thirsty as I understand it. Plus there's the issue of what to do with that nice hot exhaust which for cars is not an insignificant issue.

Cranky, power to weight ratio is not necessarily related to efficiency.

Pat - thankyou.

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RE: Let's burn more sunshine

Air cooled VWs where a tad noisy and despite power to weight potential for the day and stress levels engine life balance, the cost and noise where insurmountable. The similar design is still used in aircraft where noise is not such an issue but power to weight and reliability most certainly are.

Regards
Pat
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RE: Let's burn more sunshine

aren't 2-cycle engines inherently less effcicent than 4 stroke engines ?

i think turbines work well with a steady load, and don't respond well to rapid changes in load.

but aren't we headed towards electric/hybrid vehicles ? this at least moves the CO2 question to large scale power plants which i guess are inherently more efficient than millions (or craptillions ?) of smaller sources ? personally i'd be much happy with the AGW debate if we were encouraging developing countries to "leap-frog" the traditional gasolene engines and adopt a more electrical based engines. rather i see we're penalising the developed economies, and giving developing countries free license to do whatever they want. and don't get me started on crabon trading scams ... damnit, i started myself on it ...

RE: Let's burn more sunshine

Well the problem with mass transit, out side major cities, is it cost to much (both to install and maintain). So cars are unlikely to go away in the near future. Buses are unconfortable, and they don't go where I want to go (like near enough to my house). The roads are unsafe for bikeing, because of the bad drivers.

Sounds like a list of excuses, but where is a solution?

Would it not be better to make telacommunting a reality for more people? Why do I need to be physically at so many meetings?

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