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I watched some of it last night.
It certainly seems like certain groups have an agenda that is very short sighted to say the least.
One lone of my trips to Virginia Tech I saw an EV1 at their school of engineering. One of the students involved in investigating my idea told me it was a piece of junk.
I was leaving and had a schedule to keep with a one day 577 mile drive, so I did not have a lot of time to ask why he thought it was junk, but he was a pretty smart fellow and I had been around him enough to know he had no agenda in his statement.
Even in the thread I started on this forum about hydraulic hybrids, there seems to be a most basic misunderstanding about what is necessary to actually build a better mousetrap, as far as vehicles go.
Maybe I have fallen into the agenda trap like everyone else, but.
To me the missing link is short term high energy capacitive storage, that allows engine operation to be limited to highest BSFC levels.
It's also the capability of having a very high efficiency in power conversion into wheel torque, while maintaining that short term high capacity storage.
In that respect batteries will not do the job, because they can not recover energy as fast as they can apply energy. Maybe if you add capacitors you could build a system, but the problem there is every transformation of the state of energy invokes losses.
The ultimate bean counter is physics. Even when you build a system that is functional, it HAS to be highly efficient and competitive with the best single directional systems.
Power train efficiencies must be close to 90% for direct transmission of energy and better than 83% on regeneration of energy to make the Pulse and Glide as well as regeneration strategies effective enough to allow limiting engine operation to best BSFC.
That assumes you are using some form of IC.
Here is where I think many do not understand the most basic issue.
You must think of two separate systems in vehicles.
First is the system that consumes energy to provide motion. That is basically a one way street and typical of all non hybrid cars. Once your fuel is gone you never get it back.
The second is the system that recovers energy lost in deceleration when you have no choice, such as forced stops or steep downhill runs. In this respect electric drives fail miserably, returning only about 30% of the energy to the wheels.
Hydraulics are at 78% right now, with the threshold of success only about 5% better at 83%. It's not really engineering unless it passes the test of energy accounting. You have to get almost every bean (unit of energy) back to achieve the threshold of a truly efficient vehicle.
When you reach that threshold with SHORT term capacitive storage of energy, then you have a vehicle that will accomplish a revolutionary improvement in mileage. This is because you can Pulse and Glide the first system and use the second system to apply energy to the wheels regardless of the source of energy used in the first system.
To clarify. We use P&G to make our vehicles more efficient, but it's a lot of additional work load that is boring, repetitive, and IN MY OPINION unnecessary.
Energy accounting demands that P&G is incorporated into the vehicles operational systems, NOT IN THE DRIVERS EFFORTS.
This requires and INFINITELY VARIABLE TRANSMISSION, as well as short term capacitive storage to allow engine operation to be limited to either best BSFC or not running at all, and it does not exclude electrical operation. It's sad to see those who advocate electrical drives opposing hydraulic power trains, when the combination of both systems may actually make electric drives practical.
The simplicity of a regenerative in wheel hydraulic drive, and the resulting weight savings would allow more battery capacity and may actually be the solution to electric vehicles with the power train accomplishing regeneration above and beyond the battery as well as incorporating the battery to the extent it can absorb regeneration energy.
Electric vehicle advocates try to tell you you do not need a transmission. This is like saying just put a 1000 hp engine in your car and you don't need a transmission either.
Both statements are true in a most basic sense, but transmissions are necessary in either vehicle type to allow for reasonable acceleration without a giant gasoline engine or electric motor.
Now you may want to argue the last statement, but it does seem to be where the electric car is evolving, where some form of gearing will allow engine size to be reduced.
With the number of energy conversions in recovering linear inertia in an electric vehicle, it is doubtful it will ever reach the 83% threshold of effective P&G operation. Simply downsizing the engine or motor will not accomplish this because you must have the ability to climb sustained grades in any practical vehicle. This requires a larger engine or motor to be capable of providing a fairly high level of sustained power output.
Sadly it seems to not be well understood that that same requirement does not condemn us to driving grossly inefficient vehicles forever.
regards
Mech
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