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Hybrids Go Multi-Platinum

Astro the Prius in Olympia Wa, parked in front of a "Performance" Truck
Toyota is the name that comes to the minds of many when they think of hybrid vehicles. The Prius family is now a range of vehicles that give excellent fuel economy and emissions reductions with lots of practical interior space and utility. The Prius are not "fast" but they have plenty of power for commuting in traffic, going over mountain passes and cruising along at 70+ MPH on the freeway.
O-G or original Prius 1997-2003 gets 43MPG's in the real world

2nd Gen Prius 2004-2009 gets 46MPG's in the real world

3rd Gen Prius 2010-present gets 48MPG's in the real world

Prius C (city) compact (Aqua in Japan) 2011-present gets 50MPG's in the real world

Prius V (mini-van) 2012-present gets 45MPG's in the real world

Prius Plug in Hybrid 2012-present gets between 50 and 75MPG's depending on who is driving, how far they are driving, how often they plug it in, and other variables. The majority are averaging 63ish MPG's in the real world.

All the Prius except the Plug-in Prius use NiMH Nickel Metal Hydride batteries. The battery in my 2nd Gen Prius is a 201.6v 6.5ah battery composed of 28 modules of 7.2v (each of which is made of 6 cells of 1.2v each). Each module has a charge/ discharge controller and a relay. Together in the pack, a battery management system converts the 1.3kWh of storage into about 450Wh of usable storage. When the vehicle slows down it captures energy, when the vehicle speeds up it uses the energy it captured when slowing down to accelerate. When the Prius comes to a stop, the engine shuts off, and in many instances the engine shuts off before you come to a stop. The electric motors MG1 and MG2 in the Prius give out lots of useful torque. A throttle by wire control pedal request power from a computer that decides how to blend output from the MG1, the Gasoline motor and MG2 in the power split orbital gear device that translates power to the final drive and ultimately the wheels. There is no transmission/ the power split device is able to blend power from the two electric motors and the gasoline engine in a continuously variable way so that any combination of gas or electric power can be used to propel the Prius. Notice that all of these NiMH Prius achieve similar real world fuel economy numbers? There is a reason. The NiMH battery can only capture a small amount of energy, it cannot get energy from the grid, and the way it is managed by the computer (to optimize long term cycle life) means that very little of its total capacity is available for use by the power-train.

The Plug-in Prius uses a Lithium Ion battery approximately 4 times larger in terms of energy storage capacity 4.4kWh than the 1.3kWh NiMH batteries in the standard Prius. The Lithium battery is extremely light weight, and with more electrical energy storage, the Plug in Prius can operate in electric "stealth mode" more of the time, thus conserving fuel. The real trick to the much greater fuel economy here is replacing gasoline with stored grid power. With more grid electrons in the power train, the Plug-in Prius relies less on its on board gasoline engine for power. The gasoline engine in the Plug-in Prius works less often and less hard, and thus fuel is conserved. The electric motors in the Plug-in Prius are highly refined versions of the ones developed in the early generations of Toyota's hybrid drive technologies.

This family of Prius's gives consumers lots of real world options for a fuel efficient vehicle that runs on regular gasoline in its most affordable grade. No special low sulfur diesel engine here, but a diesel hybrid is on the way from VW in the form of a niche low volume XL1 that will get north of 200MPG's in the real world. With sleek aerodynamics and ultralight materials, the plug-in hybrid diesel drivetrain of the XL1 gives us all something to marvel at. But why should such a vehicle exist at the fringe rather than as part of the mainstream offerings of the automakers. Fear not, super-efficient ultra-light vehicles like the XL1 will come to the market.

As fuel prices continue to stay elevated globally, the economics of operating highly fuel efficient vehicle seems to make $ense to more people in industrialized countries. Toyota has sold more than 4 million vehicles that make use of their Hybrid Synergy Drive technology portfolio. We are going to see more hybrid action from all of the automakers. ACG alternators for example that combine the alternator and starter into a single device are an example of electromotive technology optimizations that make vehicles cleaner and more fuel efficient, while also making them quieter and smoother.

Mild-hybrid technologies that enable "Start Stop" or "smart stop" enable vehicles to shut off the engine when the vehicle is stopped for more than a few seconds, and with the powerful ACG starter to instantly restart the engine when the brake pedal is released. Start-stop is a lower cost hybrid technology that automakers can use to improve conventional vehicles without adding a lot of technology costs and complexity.

Even Howard my scooter is available with Start-Stop in Europe. DOT regulations and safety concerns caused Honda to omit the Start stop technology on the US version of the PCX150. The proof is already out there and widespread that adding a larger battery and powerful electric motor to the drive train of a vehicle can make it substantially better from the point of view of fuel economy, emissions reduction, torque curve improvements, smooth power delivery, and energy efficiency.

Toyota has proved that even vintage stayed battery technology like NiMH can make a hybrid vehicle great. We did not need Lithium Iron Phosphate to get really cool hybrids, but they are coming. Hybrid vehicles with LFP batteries are being developed as I post this editorial.

Why do I care so much about vehicle fuel economy ?

1. Economic Importance
2. National Security
3. Emissions Reduction
4. Improved Technology
5. Common Sense

1. The US economy and the economy of many developed net oil importing countries are negatively affected by the widespread use of inefficient vehicles that waste the imported fuel.

2. The US is forced to import oil from countries that sponsor terrorist acts against the US.

3. Hybrid vehicles release up to 95% fewer emissions than conventional vehicles. Better for public health, and thus they help to reduce the rising health care costs.

4. The technology used in hybrid vehicles is a nice contrast to the boring repeated regurgitated internal combustion suck squeeze bang blow mantra of conventional vehicles. "Stealth mode" offers a glimpse of how awesome electric vehicles can be, without any range anxiety. The Hybrids offer a good mix of improvements without sacrifices other than increased upfront costs in exchange for long terms savings.

5. Does it really make sense to waste fuel and needlessly create pollution that harms other people while fouling the environment and contributing to unpredictable climate change.

Why should an engine idle if the driver is not requesting any motive power from the pedal? Because the alternator has to keep up with the electrical loads and hydraulic loads. To liberate the engine from the toil of always running, electric motors can be integrated into the drive train that help or replace the function of the gasoline motor where the gasoline engine would be least optimal to use, such as in low speed conditions where very low power is required, or when stopped at a traffic signal.

Hybrid FTW

I dont care how fast my Prius can accelerate, most of the time I am obeying the speed limit or stuck in traffic congestion anyway ? I see no value in operating a high performance vehicle in these conditions. I traded my over-powered super-sport in for a scooter with the same thinking in mind.

Yes, the Prius will fly over a mountain pass at 90+ mph and does so without much fuss I might add. I am not admitting to the breaking of any laws, but I can personally confirm that a Toyota Prius can go faster than 100MPH and glides down a mountain pass at high speeds beautifully. No, the Prius does not handle like a go-kart, and if you want to take corners at full speeds then look to a Mazda Miata or Lotus Elise. If you need to haul 10 people and lots of gear at the same time regularly, the Prius is not the car for you. If you regularly haul lots of plywood and gravel or tow a large boat or trailer, the Prius will not do it.

For commuting, grocery shopping and running errands, and road trips and other things that normal sedans can do, the Prius does well and in many cases it does so better, with less noise, lower emissions, and at a lower cost per mile via less fuel consumed. I tend to keep Astro under 55MPH on the highways and freeways, where the aerodynamic cross over point gives superior fuel economy. It seems that 50MPH is a good minimum speed for the freeways where I drive Astro regularly.

I chuckling thinking back to 2005 when I first obtained my prius. My mother refused to ride in my car because she thought the electric motor would not give it enough power for it to be a safe car... boy how times have changed. Public perceptions about the Prius had to align with reality, and for some people that took a long time. Toyota had to sell millions of Prii before the anti-hybrid banter faded to a murmur and ultimately silence. Some people just dislike non-performance cars and think of the Prius as an eco-dork vehicle that does not compel their emotions, aside from ones of critical condemnation. I get a lot of bashing on Autoblog when I post something about hybrids in a non-hybrid discussion thread. Oh people love to bash the PriusBlack for posting obtuse truths about the virtues of electric drive technology. LOL as if I gave two mouse farts what those ignorant trolls had to say in response to my comments.. the Jokes on them..

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