The Ergosphere
Monday, January 08, 2007

Exhausting the non-options

Men will behave reasonably when all other options have been exhausted.

Nowhere does this appear to be more true than in interest-group politics.  Agricultural interests, trying to prop up their commodity prices, may finally create the condition of crop scarcity that they've always sought to secure their profits.  Per the NYTimes, they may also have created a scarcity of the materials for ethanol plants.  Ethanol production may actually turn Iowa into a net importer of corn!  Profits are soaring, for the moment.

It's doubtful that many of these farmers are thinking beyond the next year.  Suppose they succeed?  Suppose that crop prices do rise steeply, and make every year a profitable year no matter what size the harvest?  Would that be nirvana?

More likely, the consequences would lead to all the high-flyers being dragged right back to earth.

As others have noted, one can take a given amount of corn and either feed one person for a year or make one tank of E85 for an SUV.  As fuel ethanol production cuts grain inventories and raises crop prices, food prices (particularly meat) will start to increase with them.

This is almost certainly not politically acceptable.  The last time it happened, crop prices were supported by a system of production set-asides (derided as "paying farmers not to grow things"; without the set-asides, production overwhelmed demand and farmers went broke).  This worked relatively well, until one lean year cut production enough to contract grain supplies to the point that supermarket prices surged.  Consumer outcry led to the end of the set-aside program, farmers planted every acre they had, and the search for ways to solve the problem of surpluses was on once more.

Ethanol for cars was one of those solutions.  But now it's come full circle, and the body politic is about to see it as a problem in its own right.  Given a choice between fueling a 3-ton monster and food, a firm majority is bound to choose food.  The ethanol plants will see their feedstock reserved for an energy chain which ends at tables instead of pumps; a great many may be either cancelled or stand idle unless something inedible can be found to go into their maws.

It's about time this happened.  Ethanol from grain cannot displace petroleum to any great extent; its return on energy invested (EROEI) is perhaps 1.3 by the USDA's numbers, and a pathetic 1.09 by Robert Rapier's correction of their math.  Maybe it can be improved, but nothing will make it good enough to really make a difference.  Getting up to 2:1 would still require half the gross production recycled as feedstock; even if we could make do with 100 billion gallons of ethanol motor fuel, there's no way we'd be able to produce the 200 billion gallons to make the system self-sustaining.

It's time to call grain ethanol what it is.  Failure.  Distraction.  Maybe now, the public will believe it.  Let it die.

That will take one non-option off the table.  The birth defects of cellulosic ethanol may or may not kill it also; let it sink or swim on its own.  Hydrogen still has scarce infrastructure and no reasonable way of producing it from any fuel not already spoken for.  Can the Freedom Car program be long for this world either?

This is starting to look like the blonde joke which ends "... the others don't exist."

The non-options have just been joined by a real one, and from a rather surprising source.  Perhaps the most reactionary auto manufacturer in the industrialized nations has just announced a plug-in series hybrid.  If it gets to production, the Chevy Volt will be the first-ever no-compromises petroleum-optional car.  Toyota's Hybrid Synergy Drive would require some tweaking to do the same job; Honda's Integrated Motor Assist probably could not do it at all.  GM really deserves kudos for this one.

Those kudos are earned whether the Volt gets to showrooms or not.  It represents an endorsement of the concept, a move that will put the idea into the public consciousness.  No more is freedom from imported oil joined at the hip with agricultural subsidies or held hostage to some future non-fossil source of hydrogen.  With the Volt, GM has promised a return to cheap, carefree motoring at 75¢/gallon equivalent, and to let anyone with a windmill or solar panel produce their own motive power.  No matter who actually makes good on this promise first, it's now been made.

Reason is about to win this one.  Time to move on.

"The battery can be charged by plugging it in to any standard 110 V outlet and is fully charged in about 6-6.5 hours."

A standard circut is 15 amps. 110V*15A=1650W for 6.5 hours at 80% efficency that is ~9kWh either they are assuming that batteries will not be discharged to less than 45% or they are assuming a 30A circut.

"However, when the fuel tank is filled to it's capacity of 12 US gallons of gas, the Volt has a range of 640 miles. In addition, the Volt ICE is fully flex fuel capable and can run on any combination of gasoline or ethanol up to E85."

It won't go that far on E85. I assume this means that 40mi are due to the original charge and that the remaining 600mi are on gas. That would be 50 mpg, which is in the ball park for the Prius.

"That same example would also save 4.4 metric tonnes of CO2 every year from each car."

Depends on the fuel source for the generators.

"Another example of a driver commuting 60 miles a day would achieve an equivalent mileage of 150 mpg based on the engine running for the last 20 miles in a charge sustaining mode."

These numbers all assume that electricity is free. Around here it isn't. It costs me about 10 cents/kWh. If I put 15kWh in every night, that will be 5400kWh/yr. That is going to cost about $540. 15,000 mi in a 50mpg car, would be 300 gal costing about $750. But alot depends on the future course of prices.

"The only thing that isn't quite real at this point is the timing. The hold-up is that darned battery."

cough. cough.
1.65 kW * 6.5 h = 10.7 kWh
10.7 kWh / 40 mi = 268 Wh/mi

That's in the ballpark, so I believe the 6.5 hour figure.

If you buy your charging power at off-peak rates, it might only cost you 5¢/kWh.  The real advantage is that the car would let you mostly ignore the price of gasoline.  If it goes up to $5/gallon, the typical commuter's finances would hardly be affected if they were driving a Volt.  (Well, except for their balance sheet; the resale value of the Volt would go way up!)
This comment has been removed by a blog administrator.
Now, add a 120V or 240V output inverter (whatever makes sense to wire to a separate sub-panel, I guess) and an indoor-friendly way to deal with exhaust gas and intake air. Couple that with a way to circulate engine heat through your house from the garage, and maybe couple the engine cooling to your hot water heater on an external loop. Then you'll have the solution to weathering the next ice-storm blackout in heated comfort by using your car as a co-gen unit.
Judging by some of the comments here I'd say that the people ARE beginning to realise that Ethanol isn't the solution. I can't believe this research has proven Ethanol to be a viable option. I don't care how clean burning it is, 1:1 ROI makes the whole ethanol industry as pointless as the 'y2k bug' phenomenon, and yet businesses spent millions on that one also.
As I have said many times before, corn ethanol does have a point; it reduces crop surpluses and gets votes from the farm lobby.

The average voter only gets the bill.
A question:
If the Volt can go 600 miles on a 1L, 61 hp ICE engine, using just 12 gallons of gas - that's fine.
Why not use this configuration in normal cars (i.e. - without Liion batteries) ?
A 1L ICE engine, a generator, an electric motor, and here we go, at a fabulous efficiency of 50 mpg !
The Volt has only a 37 kW (50 HP) engine, and it achieves its high efficiency in part by not needing to throttle or idle.  If you got rid of the batteries you'd lose both efficiency and performance due to the required compromises elsewhere.
Ok, I see how the ICE running at steady rpm, while the electric motor takes care of idling and accelerating, is efficient. But that counts only in city driving. While driving on the highway, for long stretches, that 1L ICE engine won't be enough, and the batteries will dry up fast. So is the Volt basically a city car ?
Obviously, you did not read the references linked in TFA.  Had you bothered, all your questions would have been answered.

Here's what you didn't bother to read:

"The ICE/generator combo has enough power to keep the car going when cruising at 70 mph and after the 30 minutes of running, the battery will be completely topped up."

And my error, the Volt has a 53 kW generator.
I did read it, but I don't understand it. Forgive my ignorance.
"The ICE/generator combo has enough power to keep the car going when cruising at 70 mph and after the 30 minutes of running, the battery will be completely topped up."

Well, if it "has enough power to keep the car going at 70 mph", he says that a 1L ICE engine has enough power (regardless of batteries) to keep the car going for 600 miles at 70 mph.
So, we have here a fantastic efficiency. Ordinary cars, at the same weight, need at least a 1.5L-2.0L ICE engine to keep running (and they don't have to fill a battery at the same time). If the battery is good for only 40 miles, it contributes a negative contribution after that - i.e. dead weight, and sucking up energy while being charged.

So, something doesn't compute.

Alternatively: could it be that a configuration: ICE engine driving a generator, that drives an electric motor, that drives the wheels - is more efficient than the same ICE motor driving directly the wheels (sans generator)?
Ordinary cars don't need the displacement to keep going, they need it for acceleration.  My car (3422 lb curb weight) has a 1.9 liter engine rated at 100 kW (134 HP) and it only needs 90 HP (67 kW) to climb a 5% grade up a mountain at 65 MPH with a ton of trailer and payload.  Running bobtail on the flats with no wind, it probably uses 20 HP (15 kW).

53 kW and a bunch of batteries would be enough for even the driving I do.
Thanks for the answers.

"53 kW and a bunch of batteries would be enough for even the driving I do. "

Yes, as long as there is juice in those batteries. But when they are empty, that 53 kW ICE motor would have to push the car and feed the batteries at the same time... Can you rely on there being enough down hill stretches (or level ones) along the way for recharging of batteries ?

Then: the combination: ICE motor, generator, batteries, electric motor - doesn't it cause some energy losses along the way ? (Compared to the straight ICE motor - wheels configuration ?)
53 kW would be sufficient if I slowed to about 55 on the uphills.

Figures for 65 MPH:
Total power: 98 hp (245 ft-lb @2100 rpm)
Power against gravity: 5520 lb * 0.05 slope * 65/60*88 ft/sec / 550 ft-lb/sec/hp = 47.8 hp
Remaining power: 50.2 hp (expended against air drag, rolling resistance and drivetrain friction).

At 55 MPH:
Power against gravity: 5520 lb * 0.05 slope * 55/60*88 ft/sec / 550 ft-lb/sec/hp = 40.5 hp
Air drag and whatnot: 50.2 * (55/65)^2 = 35.9 hp
Total: 76.4 hp = 57 kW

Looks like I might have to drive a little under 55 MPH if I'm out of battery power and still want to haul that ton of trailer and cargo up mountains.  I wouldn't mind trading a little uphill speed at that load for 20% less fuel burn... on those occasions when I needed fuel.
Thanks. I think I get it now.

Do you know if the Volt car has been road-tested and actually yielded that 50 mpg result over long drives (640 mile or more)?
No, but the prediction of fuel economy is a well-developed science.
Why haven't they tested it ?
I understood there are issues with battery price and durability, that prevent them from going into production, but these issues need not prevent testing the prototypes.
Esspecially as a prototype has been built and presented to the public.
What is a prototype built for ? Only show off ?
I was interested if anyone knew where to get DC generators, It doesnt make sense to get and AC generator the get a AC to DC converter to charge on-board batteries. Polar Power makes a DC generator and a DC alternator but they are a bit expensive. A 10kw DC generator head is about $2000 and a similar AC generator head is only $350. A huge difference! I am having difficulties finding other companies that make DC generators. Any help would be great, thanks.
Post a Comment

<< Home
Talk largely about energy and work, but also politics and other random thoughts

Mail Engineer-Poet

(If you're mailing a question, is it already in the FAQ?)

Important links

The Reference Library

Blogchild of

Armed and Dangerous

Blogparent of


The best prospect for our energy future:
Flibe Energy

January 1990 / February 2004 / March 2004 / June 2004 / July 2004 / August 2004 / September 2004 / October 2004 / November 2004 / December 2004 / January 2005 / February 2005 / March 2005 / April 2005 / May 2005 / June 2005 / July 2005 / August 2005 / September 2005 / October 2005 / November 2005 / December 2005 / January 2006 / February 2006 / March 2006 / April 2006 / May 2006 / June 2006 / July 2006 / August 2006 / September 2006 / October 2006 / November 2006 / December 2006 / January 2007 / February 2007 / March 2007 / April 2007 / December 2007 / January 2008 / May 2008 / June 2008 / August 2008 / October 2008 / November 2008 / December 2008 / February 2009 / March 2009 / April 2009 / May 2009 / June 2009 / July 2009 / August 2009 / September 2009 / October 2009 / November 2009 / December 2009 / January 2010 / April 2010 / May 2010 / June 2010 / July 2010 / August 2010 / September 2010 / October 2010 / November 2010 / December 2010 / January 2011 / February 2011 / March 2011 / April 2011 / May 2011 / July 2011 / August 2011 / September 2011 / October 2011 / April 2013 / November 2013 / December 2013 / January 2014 / February 2014 / March 2014 / April 2014 / July 2014 / August 2014 / September 2014 / October 2014 / November 2014 / February 2015 / April 2015 / October 2015 / March 2016 / April 2016 / May 2016 / June 2016 / July 2016 / November 2016 / December 2016 / February 2017 / May 2017 / June 2017 / September 2017 / October 2017 / November 2017 / March 2018 / May 2018 / June 2018 / October 2018 / December 2018 / January 2019 / March 2019 / June 2019 / October 2019 / November 2019 / March 2020 / June 2020 / December 2020 / March 2021 / April 2021 / May 2021 / July 2021 / January 2022 / February 2022 /

Powered by Blogger

RSS feed

Visits since 2006/05/11: