TarynToo <[EMAIL PROTECTED]> wrote: > On Sep 17, 2005, at 10:05 PM, Darryl McMahon wrote: > > > TarynToo wrote: > > ( > > http://www.mail-archive.com/biofuel@sustainablelists.org/msg55383.html > > ) > > <snip> > >> The only way to get a diesel electric hybrid in this country is to > >> build it > > > yourself. I swear, before, I'm dead, I'm going to build a > > solar-svo-diesel-> > > electric-regenerative hybrid out of some old school bus or airport > > shuttle! > > <snip> > > > > I sympathize. Couple of thoughts and questions. > > > > With currrent commercial grade PV panels, I recommend you not install > > them on the > > vehicle, but install them somewhere where they can be aimed optimally, > > and not > > shaded. Car surfaces (hood, roof, trunk) will almost never be > > optimally aimed > > unless you live near the equator. Also, cars spend a lot of time > > parked in the > > shade - garages, beside buildings, in urban canyons. > > This is certainly true, but where we live, (south florida) and expect > to spend the next few years, (mostly south of 40 degrees N.) there's > usually plenty of sun. I'm very fond of vent skin designs, which in > sunlit structures provide a great deal of thermal protection by using > convection and radiant barriers to significantly reduce heat transfer > to the interior. A vehicle design which allowed vertical airflow in the > skin, up to and through a center mounted ridgevent, when parked, and > horizontal airflow in the skin while underway, would be much cooler > than if it was simply insulated. What better material for the outside > skin that solar panels? While current photovoltaic panels are still too > heavy and expensive to simply 'skin' a whole bus with, we constantly > read about 'the next big thing' in solar-electric. Another possibility > with such a design is to hinge the solar side panels so that they might > be better aimed while shading the sunlit side of the bus. This might > all be so heavy and unwieldy as to make it a negative energy > proposition. > > > I'm still not convinced regarding regenerative braking. The gain is > > typically > > small - 7-8% with drivers not trained for efficient driving. > > Efficient drivers get > > less benefit from regenerative braking, as they spend less time in > > braking mode. > > Drive smarter, get the benefit for free. Further, the small range > > increase from > > regen can be equalled by adding a battery or two to an electric > > vehicle. A bit > > more weight, but a lot less cost. > > I'll grant this for light vehicles on level terrain. But there some > situations where regenerative braking seems like a real advantage: > Short haul, high mass delivery, especially in city traffic. Driving 20 > tons of beer from red light to red light seems like the ideal > hybrid-electric-regenerative application. When driving in dense traffic > it's almost impossible to drive efficiently, you'd never move. > Mountain driving and hill driving, where the energy factors are > multiplied by gravity.
As I recall, the testing on regenerative braking gain was done on the SAE-J227 cycle. That is an urban cycle, with a lot of stops and starts. Seems like pretty much the best case for regen IMHO. We have some hills around here (river valley, old mountain range to the north), but nothing like the Rockies. I thought I had an even better application than your beer trucks. Garbage trucks for residential collection. Average trip leg distance - about 20 metres - 60 feet. I pitched this to the local government as an opportunity for a prototype (electric- biodiesel hybrid, with the local dump as the location for brewing the biodiesel). Got a form letter "no thanks" reply. But then this is the same municipality that has decided to put off acquisition of hybrid buses in the face of rising fuel costs that are adding about $20 million to their annual operating costs. (Hybrid buses use less fuel per mile.) > > The hybrid you are contemplating. Will it be a plug-in hybrid? I > > think that idea > > has merit. To the point I am building one. It will be a fully > > functional electric > > car with limited range - 20 to 30 km pure electric to start with. > > Once it is > > street legal in electric mode, I expect to add a biofuel generator set. > > Agreed, though we expect to be off the grid a lot. One thing about > coupling an internal combustion engine only through the > generator-battery-motor-wheels path is the much greater loss through > conversions. The elegance of the prius/civic designs is the close > coupling of the IC engine to the wheels, which means that the > generator-motor can be weaker and lighter, since it only needs to > provide a fraction (albeit large at times) of the power needs. Well, I have discussed the series/parallel/serial hybrid configurations with a lot of knowledgeable folks over the years, and reviewed the real-world performance of several. Of the serial hybrids currently on the market, the Insight impressed the heck out of me, the Prius's (1st & 2nd generations) slightly less so, and the Civic not so much. Much of the Insight gains come from lightweight construction, careful matching of the manual transmission and engine to power requirements, reduced drive- line drag and aerodynamics. However, the engine's are all larger than 1 litre. Considering I drove 1100 cc engine cars in my youth and thought they had plenty of pep, coupling these engines with high torque electric motors to get higher performance doesn't impress me that much. The engineering that has gone into all of these vehicles to mate all the components and have them work together as well as they do, does blow my socks off. However, if I can get away with a 15 hp engine instead of a 100 hp engine in my hybrid, I expect the fuel economy to reflect that. Time will tell. I don't see the same issues in conversion losses that others seem to. The drive cycle should be that the vehicle will run on electric-only mode for 10-15 km. If the trip will be longer than 20-30 km (battery capability), this is when I start up the biofuel engine. It is sized to provide average demand. So then the vehicle is using average power or more, the electricity generated goes directly to the motor (via the controller). When the motor demands less than the average amount, the surplus being generated will go to the batteries. If the batteries reach 80% of capacity in this mode, the engine will be shut off. In this operating range, I expect the conversion loss (to and from battery) to be 10% or less. Given the biofuel engine should be operating close to or at an optimal fixed speed, I think that should be more efficient than an engine that is covering a wide RPM range. It may take some work to find the optimal set-up for the engine, but that's part of the challenge. To be sure, one of the remaining advantages of the small diesel engine over the small spark-ignition engine is the higher operating efficiency. > > There has been some progress on this vehicle. I have finished the > > work on it I > > planned to do. It is now with my mechanic having the brakes redone > > from front to > > back. They were in need of complete rebuild after sitting for over 10 > > years - most > > of that not at my hands - believe it or not. So, with luck, that > > should be > > licensed and on the road before the end of the month. > > > > I have been thinking biodiesel as my biofuel, but a couple of things > > are making me > > rethink that now. First, this will be a year-round use car - > > including Ottawa > > winters - with -30C temperatures to contend with. That makes me worry > > about > > biodiesel gel and pour points as possible issues. Second, a local > > business is now > > selling E85, an option I did not have even two weeks ago. Third, > > four-stroke, air- > > cooled, small "gasoline" engines are easier to come by, and cheaper, > > than diesel > > engines with similar ratings. > > It certainly is easier and cheaper to lay hands on small gas engines > that small diesel engines, at least in north america. If you go into a > VW dealership in South Florida asking for diesel cars, you'll get > little more than a blank look. > > > So, should I go with E85 instead of biodiesel (presumably B10 to B20 > > in winter) for > > the hybrid? Does anyone have experience using E85 in a small engine? > > Recommendations? Cautions? > > I can't say. While I agree (with most of the list), that Pimentel is > just blowing smoke about ethanol production costs, it seems > counterintuitive to use a process that requires energy-sucking > distillation steps to make a biofuel, and since I don't plan on getting > much north of the 40th parallel, I'll almost never be concerned with > cold weather performance. Well, the temperature conditions are a major consideration here. As for the process for making the E85 or even E100, I have not yet researched the supplier for Topia (local distributor). However, if E100 is an option, I am certainly prepared to contact Iogen and see if we can reach an agreement. Their pilot plant is about 15 km from my house. > > The ethanol option would kind of round out the fleet. Human-powered > > bicycle. > > Electric car (Fiero conversion). Biodiesel pick-up truck. > > Electric/ethanol plug- > > in hybrid. Actually, if this works as well as I think it will, I may > > re-do the > > Fiero with the same set-up. > > Nice work Darryl, good job eh? Thanks, eh! -- Darryl McMahon http://www.econogics.com/ It's your planet. If you won't look after it, who will? _______________________________________________ Biofuel mailing list Biofuel@sustainablelists.org http://sustainablelists.org/mailman/listinfo/biofuel_sustainablelists.org Biofuel at Journey to Forever: http://journeytoforever.org/biofuel.html Search the combined Biofuel and Biofuels-biz list archives (50,000 messages): http://www.mail-archive.com/biofuel@sustainablelists.org/
