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GM Volt: just another GM public relations ploy
GM is to be lauded for proposing the Serial Plug-In Hybrid EV ("SPI") configuration in their Volt concept
car. GM correctly points out
that most of our driving is done in short trips of less than 40 miles from home, but potentially at highway speeds, not golf-cart speeds. The SPI carries a
small gas engine-generator ("genset") used only to charge the battery for longer trips, or if the driver
forgot to charge the battery.
GM however is dissimulating when it claims that the batteries aren't ready.
The Toyota RAV4-EV goes up to 150 miles on a charge (120 miles normally) without help from any gas or diesel engine.
The Toyota RAV4-EV has regenerative braking, and recharges its batteries by braking hundreds of times per day.
ELECTRIC DRIVE INHERENTLY BETTER
An electric car is much more efficient than a gasoline car. The reason is simple: there is basically only
one moving part, the motor rotor, on an electric car, and it's going in the right direction -- same as the wheels.
A gas engine has pistons going in an up-and-down motion that has to be valve-regulated, with rings, wrist-pins,
rods and lots of other moving parts, and transformed into rotary motion by the crankshaft, with the help of grease,
oil, coolant, bearings, etc. There are muffler, EGR, catalytic converter, fuel and other systems that are
just not needed on an Electric car.
A gas engine runs most efficiently at a constant power range -- usually about 3,000 Revolutions Per Minute ("RPM").
The gas engine is not suited for stopping and starting; for this reason, locomotives, long ago, were redesigned
to use the diesel engine only for generating electric power, ALL traction power comes from the electric motor.
The rationale behind this is also simple:
- Stopping the vehicle requires either turning off the engine, or interrupting
the connection between the engine and the wheels. Usually, this is done with a friction or hydraulic-fluid
clutch, which loses energy and wears out.
- The power range is poor for starting out; hence, a gas engine car must have
gearing, so that it has about 10 RPM of the engine for each turn of the wheels at low speed, but 1, or less than
one, at highway speeds.
Two Toyota RAV4-EV plug-in Electric cars charging
directly from a solar portico in Culver City.
An electric traction motor does not have these issues; it has maximum torque
at zero RPM, and handles speed ranges, reverse, and hills with electronic switching. Any substitution of "fly-by-wire"
for mechanical connection is inherently preferred. Regenerative braking, also, can be used to suck the energy of
motion back into the batteries; surprisingly, diesel-electric locomotives don't store this energy, because historically
diesel was so cheap. With the rise in energy costs, now, some do, and it's now practical to use the same
thrifty energy recovery in all vehicles.
An EV goes 3 to 6 miles on each kWh
of stored electric power. Going up hills, and accelerating in traffic, does not really use up much more energy
than driving on flat ground, because you get it back when going down hills or braking. This "3 to 6
miles per kWh" number is a theoretical limit, derived from the aerodynamics of any car, and from the fact
that the most energy lost in an EV is by air resistance, not the much lower coefficient of rolling resistance.
This efficiency is borne out in the everyday experience of EV drivers, from the 1997 lead battery GM EV1 (110 miles
with Panasonic Lead batteries), 1997 Nickel Metal Hydride ("NiMH") battery-powered Honda EV-plus (120
miles with Panasonic NiMH), 1998 NiMH Ford Ranger-EV (NiMH), 1999 NiMH GM EV1 (160 miles with Ovonics NiMH), to
hundreds of 2001 and 2002 NiMH Toyota RAV4-EV (120 miles on Panasonic NiMH).
The RAV4-EV, for example, a small SUV, can be measured on any day to hold at most 28 kWh. On that power,
it goes 80 miles at 80 mph (high wind resistance), 100 miles at 65 mph, 120 miles at 55 mph, and up to 150 miles
at 35 mph. Thus, from 3 miles per kWh up to 6 miles per kWh. The EV1, much more aerodynamic, went 4
to 6 miles per kWh.
An EV, then, goes 105 to 210 miles on the energy equivalent of a gallon of gasoline (35 kWh); but WITHOUT
the gasoline. Thus, without the high cost of oil diplomacy,
oil wars, armed forces, foreign aid to oil dictators, oil spills, oil transport, and so on. According to
the California Energy Commission, the LARGEST INDUSTRIAL USERS of ELECTRIC and NATURAL GAS (not to mention potable, subsidized water) are
the OIL EXTRACTION and REFINING industries. It's difficult to claim that electric used to charge up EVs is "dirty"
and "comes from coal", but "clean" when used to pump oil and refine gasoline.
These advantages pertain only to plug-in, real EVs that don't use the gas engine for anything but charging the
batteries.
"PARALLEL" HYBRIDS ARE GAS CARS
SPI hybrids are not currently offered for sale. In fact, of
all the hundreds of car models and millions of cars produced each year, not one is a plug-in of any sort. Remarkably,
the only "hybrids" currently offered for sale are all "parallel" hybrids, meaning that the
gas engine is primary, and the electric motor serves as a mere booster for power to achieve a higher mpg number.
These hybrids are ALL GASOLINE CARS, because they cannot plug-in. They get ALL of their
energy, ultimately, from the GASOLINE PUMP. They are NOT "half and half", they are NOT electric cars.
They are gas-burning cars with an electric booster that runs on batteries too small to plug in. Thus, ALL
"parallel" hybrids share the characteristic that they CANNOT PLUG IN, and are therefore still TIED TO
THE GAS PUMP.
The parallel hybrid gets its better mpg numbers from three
sources, all of which emulate advantages inherent to the Electric car, and absent from other Internal Combustion
("IC") cars:
- STOPPING THE ENGINE while the car is stopped in traffic, and
using complicated computer controls to open and close valves, etc., to start off. This saves idling in traffic,
which of course, real EVs never do, since real EVs don't idle and don't have emissions.
- SMALLER ENGINE because it can get away with using the electric
motor for an occasional booster.
- LIMITED REGENERATIVE BRAKING, limited because, unlike a real
EV, the "hybrid" battery is extremely small, only 1.3 kWh of which only a small fraction is useable by
the vehicle. Hence, it can only recover a tiny percentage of the energy of braking, by our rule of thumb, less
than 3 miles of all-electric range at very low speed. When the battery is full, moreover, these hybrids must
rely on mechanical braking, and are subject to the same problems as gas cars: excessive brake wear, burning brakes
on long downhill stretches. In addition, the tiny battery may mean a certain loss of power on long uphill runs
that need more torque than it can supply.
A Prius fitted with a 9 kWh or larger battery can achieve 90 mpg (more of the energy of braking is recaptured)
and if you can plug it in, it gets up to 180 mpg.
There are advantages to the "parallel hybrid", such as use of the Atkinson Cycle engine and the Continuously
Variable Transmission, both made possible by the electric motor boost at low and critical engine speeds.
AN EV IS VERY EFFICIENT; BUT THAT'S ONLY PART OF THE STORY.
Now let's look at the energy consumption of an EV, and examine why, even with charging up TWO RAV4-EV, our local
utility, SCE, still owes me over $200 in excess electric I've produced this year -- plus getting all my domestic
electric at no additional cost, of course.
Even our modest 4.2 kilo-Watt ("kW") solar rooftop system can produce up to 30 kWh of electric energy
in the summer peak period per day. This, via Time of Use ("TOU-D1") pricing, can yield up to 120 kWh
of electric CREDITS for off-peak charging.
These carry over, they are zeroed out at the end of the year, but meanwhile, we get to use them for off-peak charging
and for domestic electric.
Credits of 120 kWh per day, or about 3600 per Summer month, give me the ability to drive for more than 10,800 miles
per month in my RAV4-EV (3,600 times 3). Hence, as you can see, not only am I driving "for free",
I am using some of the money that WOULD HAVE GONE FOR GAS to pay for the payments on my solar system.
Driving more than 30,000 miles per year in two RAV4-EV currently costs my family NOTHING; if we had an average
gas car, that would be 1,500 gallons of gasoline, or at least $4,000, not counting tune-ups, oil changes, engine
repairs, smog checks, brake jobs, etc. Three years of that, plus our $100/month domestic electric, and we
have more than paid for our solar system. And it will go on producing for the next few decades, mostly without
maintenance or cost.
But there's more. Instead of being "nickeled and dimed" to death by SCE, our electric utility,
we saved over $20,000 in AFTER-TAX dollars JUST IN THREE YEARS. Depending on your tax bracket, that frees
up more than $25,000 in PRE-TAX earnings, money which could go into an IRA, for charitable donations, into a before-tax
Health Savings Plan, or other use. It's a fine feeling that this "free money" comes to us by avoiding
trips to the gas station, and avoids pumping money to overseas oil suppliers.
The solar system is ours to keep; instead of the money going away each month to feed the nearby AES power plant,
it went into hardware that now sits on our roof and is worth more now than when we bought it. Meanwhile,
it just keeps on producing more "free" electric energy.
And there's even more. Each kWh we produce helps meet daytime peak demand, which heads off brownouts and reduces
any argument for building more steam plants. The daytime 4-hour summer peak period is the only time we come
within 8% of peak electric generating capacity, and each solar system that goes in lowers the chance of shortages.
When a new power plant goes in, it sits idle 20 hours per day, because it's only needed for peaking; on the other
hand, if you just build a "peaker" unit, it's very dirty, and very expensive.
The night-time charging of the EVs actually helps the grid "balance loads", because otherwise, there's
too much electric, and generators must be ramped down to "warm start", an expensive and dirty process.
At California's Lake Castaic, and a dozen other sites, 6 powerful pumps use off-peak electric transmitted down
the Western States Power Grid, the largest DC power grid in the world, to pump water UP TO LAKE CASTAIC AT NIGHT.
The next day, the pumps turn into generators, and the "stored" off-peak electric is used to meet on-peak
critical usage. Even with a transmission loss of perhaps 20%, this cheap off-peak power is about 12 times cheaper
than daytime peak power from other sources.
The combination of SPI off-peak charging paid for by on-peak distributed electric
generation, which is referred to as "PV-EV", emulates and extends this valuable load-balancing function.
Ironically, plug-in cars charging off-peak help the grid run cleaner and more efficiently, while on-peak PV production
helps the grid avoid overloading the high-voltage transmission lines.
Hence, our off-peak charging of the EVs actually is beneficial to the grid, and
that's why electric utility companies were the only major supporter of Electric cars.
There's even more. Solar PV helps insulate and preserves the roof, because it transforms some of the sun's energy
into electric, and the air gap actually cools the home and helps protect the roof. But nothing can match
the carefree feeling of watching your electric meter go backward, knowing that you are a visible part of the solution
to the problem of global warming.
Each gallon of gas we don't burn avoids more than 20 pounds of CO2 gas being
emitted into the air (one eight-pound gallon of gasoline is mostly Carbon, atomic weight of 12; burning it takes
two atoms of Oxygen from the air and adds atomic weight of 32, so the result is almost 5 times the weight of the
gasoline fuel).
We are also, moreover, protected from upward spikes in electric rates at least for the next 25 years (the panels
are guaranteed that long at 80% of their rated output, and may last for decades longer). We have effectively paid
up-front for our electric power for the foreseeable future. If prices rise, we sell at that same price, and
our system becomes even more valuable.
With the freedom of the Electric car, assuming you can get one, you save much more money; but more importantly,
you don't need to get a smog check at all. Electric cars are exempt from that annoyance. Once, a government
emissions employee was trying to verify that we were exempt, and kept looking for a tailpipe, muffler, some sort
of engine. It was gratifying.
The Volt, as a SPI, does have a small IC engine and would be subject to some
of these regulations, especially if the genset were used much. However, many SPI drivers would just unplug and
remove the genset, replacing it with enough batteries to go 100 or more miles, and remain exempt. Even if the genset
were left in for occasional use, it would not require anything like the maintenance of an IC car; running it at
constant speed, on only isolated occasions, means much less wear and much longer IC life. Even if you leave the
IC in the EV. Some EV drivers add a "Long Ranger" trailer containing the genset, so that they can hook
it up only when they need it. In the VOLT, you could probably just plug it back in on those occasions when you
need it for a long trip.
No oil changes. No more nagging "Jiffy Lube" commercials. No engine repairs, no greasy, ill-tempered
mechanic laying some strange problem on you, "...I wouldn't let you drive that home tonight, with a third-member
like that, not to mention the receiving cylinders...it can be finished in a week, not much more than a thousand
dollars...". Mechanics, ironically, love working on an Electric car, even though there's not much
to go wrong, because there's no grease, and not much to do other than check fluids, rotate tires, maybe do a data
readout or replace a fuse.
No catalytic converter replacement. That's an expensive one.
You get to drive single in California's HOV lane, just like a Natural Gas car or a Prius; but Electric cars are
always exempt, always permitted an HOV sticker. There's no quota on the number of Electric cars in the HOV lanes,
as there are quotas for "hybrids".
Less brake wear, because of regenerative braking. The Honda EV-plus mechanic, after 60,000 miles, asked,
"...don't you use those brakes at all?". Less tire wear, more stability in an accident (the batteries
are carried under the Electric car, in a tray, providing stability; it won't turn over!).
You can drive it into your home, if you wish, or leave it on in your garage. No embarrassing oil leaks, no
exhaust, no danger.
To drive, it's easy. Nothing to start, no roaring, no coordination of clutch and engine, no stalling out;
you cannot flood the engine. New drivers can just concentrate on the fun stuff, driving. Hill climbing is
fun, and starting on a hill is a breeze, unlike the terrifying startup in a gas car on huge hills such as San Francisco.
It takes off smoothly, like an airplane, an efficient, direct transmission of power to the wheels. No slipping
on mud, snow or ice; not much need for tire chains when we drove to the ski resort.
It's clean. You never realize how dirty a gas car is, even for the occupant, until you drive an Electric
car.
One recent USC study validates other studies, and common sense, that show much higher levels of lung damage for
freeway drivers, while they are on the freeway; and that kids in close proximity (.3 mile) to freeway pollution
suffer permanent lung damage. That doesn't mean that kids farther away (1 mile) are safe; it just means that
their lungs are stunted slightly less badly than those suffering the worst damage. This affects urban design,
it is said: but so long as freeways contain IC cars spewing emissions into the air, there will never be a safe
place to live in L.A.
The biggest thrill of driving an Electric car is that you are making a visible statement that you are not part
of the war for oil. It's the most powerful political statement you can make, even more than voting, some
say.
We invite others to tour our solar PV home, view our two RAV4-EV, take a test drive, view our SCE electric bill
that shows we contributed excess electric each year the last two years ($98 and $89) and are ahead over $200 so
far this year. This is reality; we never visit gas stations except for occasional drives in our last gas
car or a rental car or truck. Our family has driven over 470,000 miles in oil-free Electric cars over the
last 9 years, 3 RAV4-EV alone are 70,000, 75,000 and 95,000 miles each, and still running strong.
Who needs gas? Not us. Don't bomb Iraq, Iran or hold hands with Saudi oil dictators on OUR account.
And we're not the only ones. There are over 300 individual, and hundreds more fleet, RAV4-EV drivers still
driving 2001 and 2002 Toyota RAV4-EV, most of which have rooftop solar systems.
One facetious argument against solar PV rooftop systems is that not everyone
has a roof over their heads, or maybe not one that they own. But not everyone has to have one, in order for PV
to make a big difference. We need to use PV where we can, and use SPI to develop innovative strategies that help
leverage solar PV power for a wider economic band of solar homeowners. Moving some of the energy we use from gasoline
to electric surprisingly also allows using some of the money saved to help pay for the up-front cost of the solar
system, and so, it's a self-financing improvement. It need not be for everyone, but once people see how it works,
they all seem to want to join up and live essentially "oil-free". Those who taste the freedom of PV-EV
feel that invisible chain from the gas pump to the lock around our necks fall off, never realizing how free you
feel never having to dread looking at the price of gasoline or risk getting smelly gas on your good clothes. People
love that taste of freedom: why not let them have the choice of PV-EV?
Ralph Vartabedian's recent story in the L.A. Times about how many families have more than one car also renders
false one major argument against Electric cars. Detractors claim that Electric cars, to be practical, must
be capable of 600 miles range and fast-charging in 10 minutes to be able to compete with gasoline or diesel IC
cars on long trips.
But most people don't rely on only one car for all uses, and, if they do, it's for driving to work, not long distance.
Most driving trips are short-, not long-distance. For long trips, it's no longer cool to tour the USA in
an IC car. Taking the plane, or, where available, train or bus, is a more likely alternative to escaping
your troubles, pulling stakes, and fleeing "to Chicago or bust".
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