Why EV + PV is great

Posted as a blog on 02.15.2007

----------------------------------------------------
Original reason for this response:
"...In physics we learned that is takes a certain amount of energy
to move a mass from point A to point B. Has the Hybrid somehow
broken this law...I always thought you can't get something for
nothing. Are Hybrid owners actually getting something for nothing or
are they just getting good mileage because Hybrids are small cars?
Joey spoke recently of the electric car. I think that was a joke
when it came to solving air pollution because when you plug it in to
charge AES has to fire up the generators to produce the
electricity. That idea died for a good reason..."
-----------------------------------------------------

Our USA fleet mileage is about 20 miles per gallon ("mpg"). That
includes hummers, SUTs, SUV, Prius, etc. The average miles driven
per person per day is, let's say, 30.

A gallon of gasoline contains the equivalent of about 35 kilo-Watt-
hours ("kWh") of electric energy. A gallon of diesel contains the
equivalent of about 40 kWh of electric energy. That's why it is
often said that "diesel cars get better mpg than gasoline cars".
It's because there's more energy in diesel than gasoline, it's a
more energy-dense fuel. Also, diesel engines have a higher
compression ratio, mechanics find them easy to work on, and they are
generally better maintained than gasoline cars; but that's another
story. Tune-ups will increase your mpg.

The conclusion is that the average USA gasoline car goes about 20
miles on the energy equivalent of 35 kWh, which is enough energy to
keep a 1000 Watt hair dryer running for 35 hours (1000 x 35 = 35,000
Watt-hours which => 35 kWh).

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
breaking the power train. 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 up to 10 RPM of the engine for
each turn of the wheels at low speed, but 1, or less than one, at
highway speeds.

An electric traction motor does not have these problems; it has
maximum power at zero RPM, and handles speed ranges, reverse, and
hills with electronic switching. Regnerative braking, too, 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.

Hence, 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 energy, 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 number is borne out in the
everyday driving of EV drivers, from the 1997 lead EV1, NiMH Honda
EV-plus, Ford Ranger-EV, 1999 NiMH EV1, to hundreds of Toyota RAV4-
EV. The number is demonstrable; the RAV4-EV, for example, a small
SUV, can be seen and measured 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.

Thus, an EV goes 105 to 210 miles on the energy equivalent of a
gallon of gasoline (35 kWh). 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. Did you
know that, according the the California Energy Commission, the
LARGEST INDUSTRIAL USER of ELECTRIC and NATURAL GAS (not to mention
potable, subsidized water) is 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
refine gasoline.

These advantages pertain only to plug-in real EVs that don't use the
gas engine for anything but charging the batteries.

"PHONY" HYBRIDS ARE GAS CARS

The only "hybrids" you currently can buy are ALL "parallel" hybrids,
meaning that the gas engine is primary, and the electric motor just
serves as a 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 "phony" hybrids share the
characteristic that they CANNOT PLUG IN, and are therefore still
TIED TO THE GAS PUMP.

The "hybrid" gets its better mpg numbers from three sources, all of
which emulate advantages of the EV:

1. 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.

2. SMALLER ENGINE because it can get away with using the electric
motor for an occasional booster.

3. LIMITED REGENERATIVE BRAKING, limited because, unlike a real EV,
the "hybrid" battery is laughably small, only 1.3 kWh (.4 kWh is
usable). Hence, it can only recover a tiny percentage of the energy
of braking. When full, 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, loss of power
on long uphill runs.

A Prius fitted with a 9 kWh 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 other advantages to the "phony hybrid", such as use of the
Atkinson Cycle engine and the Continuously Variable Transmission 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, SCE still owes me over $200 in
excess electric I've produced this year -- plus my domestic
electric, of course.

Even a modest 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 are we
driving "for free", we are using some of the money that WOULD HAVE
GONE FOR GAS to pay for the payments on our solar system.

Driving more than 30,000 miles per year in two RAV4-EV currently
costs us NOTHING; if we had an average gas car, that would be 1,500
gallons of gasoline, or at least $4,000, not counting tune-up, oil
change, 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.

But there's more. Instead of being "nickeled and dimed" to death by
SCE, 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. The solar system is ours to keep;
instead of the money going away each month to feed the AES power
plant, it went 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 peak is the only time we
come close to peak capacity, and each solar system that goes in
lowers the chance of shortages. When a new 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 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 the 20% loss, this cheap off-peak power is about
12 times cheaper than daytime peak power from other sources. Hence,
our off-peak charging of the EVs actually is beneficial to the grid,
and that's why we, like other non-solar TOU-D1 users, get the
differential rates. It's a numbers thing.

Now there's even more, solar PV helps insulate 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.

We are also, moreover, protected from upward spikes in electric
rates at least for the next 25 years (the panels are guaranteed for
80% performance, but may last for decades longer), because 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 DMV employee was trying to verify that we were exempt, and
kept looking for a tailpipe, muffler, some sort of engine. It was
gratifying.

No oil changes. No more annoying "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 love the Electric car, 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 the HOV lane, just like a Natural Gas car
or a Prius; but Electric cars are always able to do so, 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. 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 in San Francisco.

It's clean. You never realize how dirty a gas car is, even for the
occupant, until you drive an Electric car. We are only now
beginning to do the studies that show much higher levels of lung
damage for freeway drivers, while they are on the freeway; and that
kids in close proximity to freeway pollution suffer permanent lung
damage. That doesn't mean that kids farther away are safe; it just
means that their lungs are stunted only slightly.

And the biggest thrill of driving an Electric car, 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.

You are invited to tour our solar PV home, view our two RAV4-EV,
take a test drive, view our TOU 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. It's not
for everyone, but those who taste the freedom, when that invisible
chain from the gas pump to the lock around your neck falls off, just
love that taste. Why not let others have the choice of driving
essentially "oil-free"?

Click for EVnut.com_home page