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Corn prices are on their way down and starting to stabilize, and tight-budgeted corn ethanol plants are starting let the air out of their lungs a little. With no rain for crops and a whole lot to skittish speculators, corn prices skyrocketed the last few months, leaving ethanol plants to struggle with making any sort of profit or getting any sort of financing from banks. But with prices coming down, plants are slowly picking up, including VeraSun Energy Corp whose
While the average price for a bushel of corn during the last 15 years was $2.25 to $2.35, during 2008 the prices spiked to as much as $7 during July, creating widespread doubt as to the usefulness of corn as ethanol and making big investors ditch the scene. Lower prices are great for the corn ethanol plants, yet aren’t great for farmers who already can’t make enough money from corn to get ahead from year to year – a further black underline that corn is not a solution for ethanol production despite new improvements to the process.
Even Mark Luitjens, an ethanol consultant in the industry since 1992, says that other biomass sources from ethanol can be pursued, such as corn cobs, wood waste and household waste – and some corn ethanol companies are expanding to include cellulosic ethanol plants in their line-up, while other companies are already opening commercial-scale plants – but ethanol is not the end-all-be-all answer for our fuel needs.
"Ethanol is probably not the solution for our energy needs, but it is part of the solution. We are going to need a lot of energy in the future -- solar, wind, nuclear and hydro, too -- whatever we can make.” Luitjens said. EcoGeek reaction to statement: Duh + Amen.
Via Chicago Tribune, Aberdeen American News; photo via soilscience
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written by Lane, August 05, 2008
405-450Gal EtOH/Acre Corn based Ethanol
1000 Gal/acre for cellulosic Depending on Feedstock and efficiency.
Most companies out there have not accomplished commercial scale yet.
I am not sure about Solar..
The biggest problem with Hydrogen power is that it is hard to store it. Hydrogen is a gas at room temperature and requires a lot of pressure to store for transportation; this causes issues with weight and explosivity. Not to mention there are no fueling stations
One way we could overcome this issue would be to use existing fuels and run them through a fuel Cell Post Reforming.. I know Ballard does stuff with that PEM's or something like that.. I assume that would take off before Pure hydrogen fuel..
But I am not an Expert...
As for Vera Sun Construction of that Plant was started in 2006 and was completed in 2008 if my memory serves me right...
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written by Doug, August 05, 2008
I went and found some numbers:
http://teslafounders.files.wordpress.com/2008/07/slide033.gif
The numbers of interest from this slide are:
- A cellulosic crop ("Miscanthus") yielding 15 tons
per acre (of farmland), then 50 GGE (Gallons of
Gas Equivalent) per ton.
- A concentrating PV installation giving 380 MWh per
acre (of desert land) per year.
- A Tesla car can go 4900 miles per MWh.
For jet planes, I don't know how the burning of diesel will compare w/ the direct burning of hydrogen. So I can't compare it here.
For large trucks and ships, let's assume a diesel-electric arrangement (i.e. an internal-combustion engine fueled by diesel driving a generator which then drives an electric motor -- a serial hybrid arrangement.) I don't know the mileage very well for these vehicles, so let's use the Tesla to do the comparison.
If you put a diesel-electric arrangement in a non-sportscar about the size of a Tesla, seems like it could get a good deal better than the 50mpg a good regular diesel will get. Let's be generous and say 100mpg. So for this car, we get 15 tons/acre * 50 GGE/ton * 100mi/GGE = 75000 miles per acre.
For the hydrogen side, let's take a hypothetical Tesla powered by hydrogen fuel cells. And we'll say the hydrogen is produced with the electricity from the solar installation, incurring a 75% loss of energy due to the conversion of the electricity to hydrogen and back. This car will get 380 MWh/acre * 0.25 * 4900 mi/MWh = 465500 miles per acre.
So switching from a serial-hybrid setup with an optimal ethanol ICE to a hydrogen fuel-cell setup will increase the miles yielded per unit of land by 46500/7500 = 6.2 times.
Of course, this is ignoring the other transportation and storage issues of hydrogen. Though it also ignores the additional energy inputs needed to make the ethanol.
So it looks like the energy-per-unit-land benefit of hydrogen will be large, but still less than an order of magnitude. The convenience of having a fuel for shipping or trucking that doesn't need to be kept at either cryogenic temperatures or extremely high pressures may well be worth the difference. Even if hydrogen is ultimately better, it seems likely that it'll be more of a "second generation" solution, along with space-based solar and maybe some early smatterings of fusion power. Biofuels will work fairly well in the meantime, and the transition to it will be much, much easier in the short run.
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written by Lupin, August 05, 2008
http://www.cinemocracy.org/video/letter-future-president-147
thanks for your site!
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written by Yoshi, August 06, 2008
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written by Lane, August 06, 2008
In order for a Car to travel It must be able to Store Some Fuel... Econ. Of Scale usually help produciton as well...Home Based and Store by Store Hydrogen production would be great but then Customers would have to be willing to put up the Capital... I suppose with a little work Hydrogen could be piped through Existing Natural Gas Lines
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written by Doug, August 06, 2008
Ultimately, the total solar wind capacity will be enough that there will be periods of peak power production that exceeds demand by a good margin; enough to even exceed the storage capacity of the car & truck batteries connected at that moment. For those times, hydrogen-generating points, located near the points of use (e.g. airports, seaports), could take advantage of the low electricity prices to "tank up" on their hydrogen supplies.
But that still leaves open the question of storage in the vehicles themselves. Having this on an average car or small truck is probably not worth it, compared to what batteries will be able to do. For the more energy-density-demanding applications like airplanes, ships, and large trucks, it will have to be seen whether hydrogen storage on the vehicles is worth the additional energy per $ that can be obtained from hydrogen, vs. what biofuels can offer.
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I'd like to see any numbers from out there, on how much biofuel can be produced from an acre of land per year -- of whatever type: cellulosic ethanol, algae biodiesel, etc. -- vs. how much hydrogen can be produced with that land, from PV or other solar.
I'd imagine the energy collected and stored as hydrogen, despite it's inefficiency, would far exceed that of even the best biofuel harvest. It just remains to be seen as to whether it can be stored well enough for use in airplanes, ocean liners, and big trucks (basically, the vehicles needing a lot of range).