Oops, looks like I misread the converter I used, looks more like 0.008 hp as Mike posted, no way that's real.Originally Posted by Doug Garson
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Oops, looks like I misread the converter I used, looks more like 0.008 hp as Mike posted, no way that's real.
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6.5 watts is roughly what you can get (for short period) out of a single D-cell. So, yeah, not going to run a car down the road at 50mph.
But to be fair, the .23 amp figure was a misprint, corrected in a later edition of the magazine. The intended claim was 23amps. Still absurd at .8HP - missing one more zero, one suspects.
The Mother Earth News gang built their own version of the hybrid around a Subaru and a Lombardini diesel and observed:
So now they are "cruising" at 30mph using between 4 and 8 hp. Zero located.In reality, the motors that we bench-tested at 30 volts had free-running draws of about 40 amps at 4,800 RPM ... which—under load on the highway at 30 volts—increased to 100-150 amps on level ground at 30 miles per hour, with the car in third gear.
Last edited by Steve Demuth; 11-05-2020 at 9:09 PM.
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Wikipedia lists a Cd of 3.
Probably derived in a windtunnel with crepe paper streamers.
Still - this clinking, clanking cacophony of caliginous junk actually ran down the road without killing the operator.
Compared to even 4 bangers of its day, this thing was a has miser.
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Good detective work Steve. Realistically, if you start with gasoline as the prime fuel, why would burning it in a internal combustion engine (with losses) to drive a generator (with losses) to generate electricity to run an electric motor ( with losses) be more efficient than just burning it in the ICE (with lisses) to drive the wheels? The only thing you gain is regenerative braking so maybe in stop and go traffic you might come out ahead but not cruising at 50 mph.
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As described in the first article, the batteries are held as reserve for peak current demand. Honda's first Insight hybrid IMA system worked this way.
The battery system captures some of the momentum during braking using the drive motor as a generator to be sent back out to the wheels on acceleration. This is a huge fuel saving feature.
We're concentrating on the little gas motor, but it's the belt driven generator that escapes attention. That component would have a variable load, requiring sophisticated management.
The FSR routes power four ways - direct drive to the motor, trickle current to the battery stack, regen braking to the battery stack and DC from the battery to the motor.
I'm guessing this part of the equation was problematic in 1979.
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30 volts at 150 amps is 4500VA. In reality, you need more than 750 watts for a HP, but even at 750, that's only 6HP. With losses it's probably under 5HP, and 150 amps is more than the generator can supply. No matter what, the generator cannot supply more than 5Hp because that's the size of the motor driving the generator. With losses, the output from the generator has to be less than 5HP.
At 100 amps at 30 volts, that's 3000VA, or an ideal case 4HP. More likely closer to 3HP. That does not produce a realistic vehicle. It would be extremely slow.
Mike
Last edited by Mike Henderson; 11-05-2020 at 10:17 PM.
Go into the world and do well. But more importantly, go into the world and do good.
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Companies that are spending a ton of money on buying new vehicles and converting them to electric are mostly doing it to gain a "green" reputation with various environmental groups. Amazon has a bad rap with environmental groups due to all the fossil fuels they burn to keep their delivery network running.
No company is doing commercial conversions of new vehicles to electric today to save money. There doesn't seem to be any financial savings by the time you spend as much as the vehicle cost to convert it to electric. It will more financial sense once these vehicles come from the factory with electric drivetrains with no conversion necessary.
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That's a claim to understand what motivates a concern like Amazon.
There are many ways to advertise, certainly.
https://blog.aboutamazon.com/sustain...-shipment-zero
The focus of attention is on Amazon, where logistics indicate a full truck driving to multiple customers produces less emissions than each customer driving to shop alone. The deserved knock is against next day shipping which increases emissions.
That's on the customer - not the purveyor.
https://footwearnews.com/2019/busine...nt-1202788336/
No doubt - however the verified existence of a small fleet of Transit EV (converted by Lightning repower) indicates the platform makes enough sense to invest in the expense.
Amazon's buying scale means they pay less per unit (both the stock van and swapped drivetrains) and have a financial case to be made regarding power savings. Remember that most of a driver's day in congested areas is spent searching for parking, idling or stopped.
In the Boston area, deliveries are made from a secure parking space to multiple addresses.
The Rivian initial order is for 100,000 units. No numbers available on the converted Transit vans.
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Changes in the US tax code likely drive this, as the depreciation schedule was accelerated (effectively a subsidy to encourage new vehicles purchases).
"Benefits under the law, which begin to phase out in 2022, double the amount of depreciation cost companies can claim for the first year of vehicle ownership — to as much as 100% in some cases. That makes it easier to buy the vehicles, which start at around $30,000.
While the tax reform and stepped-up competition for parcel deliveries have goosed fleet sales, it’s unclear how much longer this segment of the industry will be able to buoy the broader U.S. auto market. Dealers expect to sell fewer than 17 million new cars and trucks in 2020 after a five-year run above that threshold."
https://www.latimes.com/business/tec...-to-van-makers
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The point is we're shifting focus from a shade tree stage to full industrial output on a national scale. When this happens, prices come down.
See: LS swap
Last edited by Jim Matthews; 11-06-2020 at 7:31 AM.
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Yes, and we know exactly what this looks like when real engineers design it with real data and an ISO factory to build it. The road is full of 3rd generation Priuses, which are essentially the car these garage mechanics were trying to build, with advanced battery technology to replace the lead acid cells in their experiment, a highly optimized drive train that combines the electric motor/generator(s) with planetary transmissions to create a true multi-source, CVT, a highly efficient Atkinson-cycle ICE, and the best aerodynamic profile you can probably get out of a passenger sedan.
I've owned 4 of them. In perfect conditions - level road, dry air in the 60s or 70s (so no heater and no air conditioner), properly inflated tires, you can get 60mpg for extended stretches of continuous travel. In realistic conditions you get somewhere between the low 40s and low 50s.
I would be very surprised if anyone ever designs a better (from an efficiency point of view) ICE-electric hybrid passenger car.
So, astonishing a feat as those late 70s garage mechanic experiments were, I'd bet my last ever Prius (we've got a Volt now, in which the ICE rarely runs for 8 months of the year, and provides only half the energy we need the other 4, and will go fully electric next time) were not getting 50 mpg in real use.
Except I can't because I'm trading the Prius and an older Tacoma in tomorrow for what may be the last 5-speed manual, non-extended cab light pickup for sale in the midwest. Ever, the way things look. But that was a different thread.
Last edited by Steve Demuth; 11-06-2020 at 8:58 AM.
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So many things you've got wrong there.
http://autocaat.org/Technologies/Hyb...0the%20vehicle
The advantage of hybrid systems is that each motor operates in it's most efficient range.
The Kia Optima PHEV illustrates this quite clearly.
Compare the hybrid version to the stock GDI.
https://www.fueleconomy.gov/feg/noframes/39783.shtml
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Small engine that's just producing electric power generation...same way the Chevy Volt was set up. You do burn fuel, but the engine is small and sips compared to an ICE engine that's actually providing direct motive power to the drivetrain.
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The most expensive tool is the one you buy "cheaply" and often...
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I never said I had any doubt that Amazon is buying electric delivery vehicles. What I said is an vehicle converted to electric is probably not going to save any money over the lifecycle of the vehicle versus an ICE vehicle.
Rivian is making fully electric vehicles from the ground up that will likely sell for less than a vehicle that is converted to electric. These vehicles will also likely cost less over the lifecycle of the vehicle. Electric transit buses are very expensive to purchase up front, but over the twelve year life of the vehicle they save money. The big money savings is in repairs and maintenance. Of course, most taxpayers don't like electric buses because all they see is the upfront cost is several hundred thousand dollars higher.
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Amazon has never had a problem with losing money in pursuit of a long-term goal (in this case zero-emissions.) So much of it is driven by Jeff Bezos’ vision (and yes, I am an investor.)
Hmm, I wonder if his space operations’ “losses” could be written off, or would the IRS disallow it, given that it’s clearly a hobby. ;^)
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I'll never pretend to understand how US tax regulations work. I always thought a business had to make money in something like three out of seven years to deduct business expenses from income. The intent of the law is to stop people from running a "business" simply as a tax shelter. There are plenty of large businesses that lost money for many years yet were still treated as a regular business by the IRS.
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Don't see how the size of the engine makes a difference, in the end you are doing x amount of work based on how far and fast the car moved and how fast it accelerated. I think it must be because the engine runs at a constant (optimum) speed and regenerative braking converts lost energy from braking into stored energy in the battery. Don't understand how the size of the engine makes that much of a difference if the work done is the same.
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