Electric Cars are Toys for the Rich

Posted by PITHOCRATES - April 22nd, 2014

Week in Review

It turns out that the majority of electric car owners share something in common.  They’re rich (see Electric-Car Buyers Younger And Richer Than Hybrid Owners by Jim Gorzelany posted 4/22/2014 on Forbes).

Based on calendar-year 2013 sales, the study found that 55 percent of electric vehicle buyers are between 36 and 55 years old and have an average household income of $175,000 or more. By comparison, 45 percent of those driving hybrid-powered models off the lot are 56 years old or older (compared to just 26 percent of new EV owners), with only 12 percent having an annual income of $175,000 or higher.

So electric cars are toys for rich people.  Why?  Because working-class people can’t afford to throw money away.

This would more or less reinforce the popular wisdom that hybrids, which typically cost only nominally more than comparable conventionally powered models, appeal more to family minded penny-pinchers than do the pricier EVs, which pack more in the way of high-tech luster and are often purchased as rolling status symbols (they also require a certain infrastructure – i.e. a garage with an updated electrical system for charging – and because of their limited range are usually the second or third car in a family’s fleet)…

… buyers of both EVs and hybrids tend to reside in more affluent zipcodes than typical consumers, with most green-car buyers clustered in hip cities along the west coast.

A gasoline-powered car is utilitarian.  It’ll get you to and from work.  Day or night.  Rain or shine.  Hot or cold.  If you need heat, headlights, windshield wipers and an extra hour to get home because of slow rush-hour traffic the gasoline-powered car gives you these things.  Unlike an electric car.  Because all of these things drain the battery.  Making getting home in night, rain and cold a risky proposition.  Especially if you get stuck in rush-hour traffic.  Which is why electric cars are “usually the second or third car in a family’s fleet.”  And who can afford having 2-3 cars in a family?  People earning more than $175,000 a year.  People who take their electric car out for nice, short afternoon drives.  Then get into old reliable (gasoline-powered car 1 and/or 2 in the family’s fleet) when they really need to get somewhere.

But even having two other cars can’t do anything about the weather.  For rich people in Minnesota are probably not driving their electric car to work in a February blizzard.  Which is why the most popular places to own and drive an electric car are on the west coast.  Where it rarely is winter.  So the rich may take the electric car out of the stable for a pleasant afternoon drive.  But working class people who have to deal with night, rain and cold on a daily basis will be driving to work as they always have.  In their gasoline-powered car.  For after a hard day’s work there is nothing better than going home.  Which is why they drive gasoline-powered cars.  Because they will always get you home.



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Hot and Cold Weather reduce Range of Electric Cars

Posted by PITHOCRATES - March 22nd, 2014

Week in Review

AAA makes a lot of money during cold winters.  Because when the temperatures plummet a lot of batteries won’t start their cars.  A low cost service call for AAA.  For all it requires is about 5 minutes of time on site and a pair of jumper cables.  Connect the cables to the dead battery.  Give the AAA vehicle a little gas to increase alternator output and the car with the dead battery will start up like it’s a summer’s day.  And as soon as it does the driver can drive home.  She doesn’t have to wait for the battery to charge.  For it will trickle charge on the drive home.  While the car’s alternator will provide all the electric power needed to run the defroster blower on the windshield, the electric defroster on the rear window, the headlights, the turn signals, the stop lights, the radio, whatever.  Once the car starts gasoline will do the rest by providing the rotational motion that spins the alternator.  None of this could happen, though, with an all-electric car (see Electric car range fluctuates in extreme weather, reports AAA by Richard Read posted 3/21/2014 on The Christian Science Monitor).

We’ve known for some time that battery range in electric vehicles can fluctuate in response to temperature. However, studies and simulations have produced varying estimates of how much range owners can expect to lose…

To carry out its tests, AAA used a 2014 Ford Focus Electric Vehicle, a 2012 Mitsubishi iMIEV, and a 2013 Nissan Leaf…

When tested at the moderate temperature of 75 degrees Fahrenheit, AAA says the three vehicles averaged 105 miles per charge. After the thermostat was cranked up to 95 degrees, however, that range plummeted to just 69 miles.

The batteries performed even worse in cold weather. When the vehicles were tested at 20 degrees Fahrenheit, they averaged just 43 miles — a 57 percent reduction in range.

Imagine yourself driving home in a February blizzard after work.  With a 30 minute drive home on the expressway.  Which is crawling along at a slow speed due to the bad weather.  Your normal 30 minute drive home turns into an hour.  As you inch along in heavy traffic.  With your wipers running.  Your heat on.  Your headlights on.  Your windshield defroster blower running.  Your rear window defroster on.  And your stop lights blinking on and off as you ride your brake in stop and go traffic.  All of these things just sucking the charge out of your battery.  Imagine all of that and tell me which kind of car would you rather be in.  An all-electric car that has only 43 miles of charge in it?  Or a gasoline-powered car that can sit in that traffic for 3 hours (or longer) before getting you home with everything running while keeping you toasty warm inside?

If you don’t want to wait for a tow truck standing next to your all-electric car in that blizzard to tow you home after it runs out of charge in that stop and go traffic I’m guessing you’ll probably choose the gasoline-powered car.  Which is why few people are buying these all-electric cars.  People don’t want a car that can only be driven in nice weather when there is little traffic on the road to slow your way home.  That’s why they choose gasoline-powered cars.  Because it will drive in anything and will always get you home as long as there is gasoline in the tank.



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Car Companies making more Electric Cars that people will not Buy

Posted by PITHOCRATES - March 9th, 2014

Week in Review

Auto makers are caving in to green paranoia.  Fooling themselves that electric cars are worth the investment (see Geneva Motor Show: Electric cars no longer the exception? by Theo Leggett posted 3/6/2014 on BBC News Business).

The Porsche Panamera S is quite a car. Sleek, powerful and aerodynamic, it’s capable of 167mph.

But that’s not all. The version on display here in Geneva is also able to travel for about 20 miles on nothing but battery power.

It is, of course, a hybrid. It has an electric motor sitting alongside a 3-litre petrol engine. It is fast, powerful and remarkably economical. Porsche claims it can drive for 91 miles on a single gallon of petrol.

Wow.  A whole 20 miles on battery.  A Ford Taurus with a full tank of gas will take you 522 miles on the expressway.  With heat or air conditioning.  In snow or rain.  Night or day.  That’s what the internal combustion engine gives you.  The ability to get into your car and drive.  Whenever.  Without worrying if you have enough charge in the battery.  Or whether you can risk running the heat or use the headlights when you’re running low on charge.   All you need is gasoline.  And when you’re low on gasoline you just have to spend about 10 minutes or so at a convenient gas station to refill your tank.  Something no battery can do.  For the fastest chargers (i.e., the highest voltage chargers) still require more than a half hour for a useful charge.

Now, under pressure from regulators around the world, carmakers have been working hard to reduce emissions and fuel consumption. So hybrids have become decidedly mainstream…

“There’s no doubt in our mind that it’s coming and it’s coming quickly and there is legislation supporting this in many cities.

“You can drive into London and pay zero congestion charge, for example. There are taxation incentives in the UK, but also in the US and Asia as well…

“We know our customers now,” he says, “and we remain totally convinced that electric cars have a strong, strong place in the market…”

Yet although sales of electric vehicles are growing rapidly, they remain a tiny fraction of the global total. For the moment, the internal combustion engine remains king.

The only thing causing electric cars to become mainstream is the coercion of government.  Legislation.  The only way you can make an electric car more attractive than a gasoline-powered car.  Also, just to get people to buy electric cars requires massive government subsidies.  No.  Hamburgers, fries and Coke are mainstream.  Because you don’t have to subsidize them or coerce people to buy them.  In fact they are so mainstream that some in government use legislation to try and stop people from buying them.

The internal combustion engine is king and will remain king until you can drive an electric car as carefree as a gasoline-powered car.  Until the electric car makers can give us the range and the ability to use our heaters and lights without sweating profusely as we sit in gridlock during a blizzard worrying whether we’ll ever make it home people just aren’t going to buy an electric car.  Because people want to know they will make it home safely.  And right now nothing does that better than the internal combustion engine.



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Engine Block Heaters and Battery Heaters

Posted by PITHOCRATES - February 19th, 2014

Technology 101

As Matter loses Heat it shrinks from a Gas to a Liquid to a Solid

There is no such thing as cold.  Cold is simply the absence of heat.  Which is a real thing.  Heat.  It’s a form of energy.  Warm things have a lot of energy.  Cold things have less energy.  The Kelvin scale is a measurement of temperature.  Like degrees used when measuring temperature in Celsius or Fahrenheit.  Where 32 degrees Fahrenheit equals 0 degrees Celsius.  And 0 degrees Celsius equals 273.15 kelvin.  Not ‘degrees’ kelvin.  Just kelvin.

When something cools it loses heat energy.  The molecular activity slows down.  Steam has a lot of molecular activity.  At 212 degrees Fahrenheit (100 degrees Celsius or 373.15 kelvin) the molecular activity decreases enough (i.e., loses energy) that steam changes to water.  At 32 degrees Fahrenheit (0 degrees Celsius or 273.15 kelvin) the molecular activity decreases enough (i.e., loses energy) that water turns into ice.

The more heat matter loses the less molecules move around.  At absolute zero (0 kelvin) there is no heat at all.  And no molecular movement.  Making 0 kelvin the ‘coldest’ anything can be.  For 0 kelvin represents the absence of all heat.  As matter loses heat it shrinks.  Gases become liquid.  And liquids becomes solid.  (Water, however, is an exception to that rule.  When water turns into ice it expands.  And cracks our roadways.)  They become less fluid.  Or more viscous.  Cold butter is harder to spread on a roll than warm butter.  Because warm butter has more heat energy than cold butter.  So warm butter is less viscous than cold butter.

Vehicles in Sub-Freezing Temperatures can Start Easily if Equipped with an Engine Block Heater

In a car’s internal combustion engine an air-fuel mixture enters the cylinder.  As the piston comes up it compresses this mixture.  And raises its temperature.  When the piston reaches the top the air-fuel mixture is at its maximum pressure and temperature.  The spark plug then provides an ignition source to cause combustion.  (A diesel engine operates at such a high compression that the temperature rise is so great the air-fuel mixture will combust without an ignition source).  Driving the piston down and creating rotational energy via the crank shaft.

For this to happen a lot of things have to work together.  You need energy to spin the engine before the combustion process.  You need lubrication to allow the engine components to move without causing wear and tear.  And you need the air-fuel mixture to reach a temperature to burn cleanly and to extract as much energy from combustion as possible.  None of which works well in very cold temperatures.

Vehicles operating in sub-freezing temperatures need a little help.  Manufacturers equip many vehicles sold for these regions with engine block heaters.  These are heating elements in the engine core.  You’ll know a vehicle has one when you see an electrical cord coming out of the engine compartment.  When these engines aren’t running they ‘plug in’ to an electrical outlet.  A timer will cycle these heaters on and off.  Keeping the engine block warmer than the subfreezing temperatures.

The Internal Combustion Engine is Ideal for use in Cold Temperatures

At subfreezing temperatures engine oil because more viscous.  And more like tar.  This does not flow well through the engine.  So until it warms up the engine operates basically without any lubrication.  In ‘normal’ temperatures the oil heats up quickly and flows through the engine before there’s any damage.  At subfreezing temperatures oil needs a little help when starting.  So the oil sump is heated.  Like an engine block heater.  So when someone tries to start the engine the oil is more like oil and less like tar.

Of course, for any of this to help start an engine you have to be able to turn the engine over first.  And to do that you need a charged battery.  But even a charged battery needs help in sub-freezing temperatures.  For in these temperatures there is little molecular action in the battery.  And without molecular activity there will be little current available to power the engine’s starter.  So there are heaters for batteries, too.  Electric blankets or pads that sit under or wrap around a battery.  To warm the battery to let the chemicals inside move around more freely.  So they can produce the electric power it needs to turn an engine over on a cold day.

Once an engine block, the engine oil and battery are sufficiently warmed by external electric power the engine can start.  Once it warms up it can operate like it can at less frigid temperatures.  The engine alternator powers the electrical systems on the vehicle.  And recharges the battery.  The engine coolant heats up and provides heat for the passenger compartment.  And defrosts the windows.  Once the engine is warm it can shut down and start again an hour or so later with ease.  Making it ideal for use in cold temperatures.  Unlike an electric car.  For the colder it gets the less energy its batteries will have.  Making it a risky endeavor to drive to the store in the Midwest or the Northeast during a winter such as this.  Something people should think about before buying an all-electric car.



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The Ford Model T is probably a Safer Choice for a Cross-Country Trip than an All-Electric Car

Posted by PITHOCRATES - February 16th, 2014

Week in Review

The United States is no doubt tired of winter.  It’s been a long one.  Snow, ice and cold.  Especially cold.  With below-zero temperatures in northern states.  And freezing temperatures even in southern states.  In fact, it’s been such a brutal winter that every state in the United States but one has snow.  Florida.  It’s just been a long, cold winter.  But it’s been a good one for those in the snow removal business.  And for those in providing a jump-start for dead batteries.  For batteries just don’t like cold weather.  Which is another problem with all-electric cars.  In addition to finding a place and the time to charge them (see Tesla Model S Electric Car Versus … Ford Model T? A History Lesson by John Voelcker posted 2/14/2014 on Yahoo! Autos).

While the fast-expanding network of Tesla Supercharger DC quick-charging stations now permits both coast-to-coast and New York-to-Florida road trips by electric car, the magazine conducted its test last October…

And as it points out, in its area of the country (Ann Arbor, Michigan), there were no Supercharger stations last fall.

(There is now one, along I-94 in St. Joseph, Michigan, 26 miles north of the I-90 cross-country corridor–one of 76 operating U.S. Supercharger locations as of today.)

So it couched its Tesla-vs-Model T test as the equivalent, a century later, to the question it imagined potential buyers of the first automobiles may have pondered: How does this stack up against my old, familiar, predictable horse..?

In due course, small roadside businesses sprang up to sell gasoline for the newfangled contraptions, usually in the same place they could be repaired.

But travelers couldn’t be confident of finding gasoline until well into the 1920s, a result of the Model T turning the U.S. into a car-based nation almost by itself.

Imagine driving across a state the size of Michigan on a road trip.  From St. Joseph to Detroit on the other side of the state it’s about 200 miles.  Which it will take you over 3 hours to drive at posted speed limits.  Now imagine driving this with only one gas station to stop at.  One you’re not familiar with.  One that you will have to drive around a little to find.  While you’re running out of energy.  Now imagine you’re in an all-electric car.  And you find this one charging station and there are 4 cars ahead of you waiting for their 30-minute quick charge.  Which could increase your charging time from one half hour to two and a half hours.

Every gas station has electric power.  So every gas station could sell electricity for electric cars, too.  If someone had to wait a half hour to charge their car that is a lot of time they could be buying stuff from the mini mart all these gas stations have.  So why aren’t they building these things?  Is it that they don’t want the liability that might come from a faulty charger starting a battery fire?  Is it because there are so few all-electric cars to waste the investment on?  Is there a question of how to charge for electricity?  Or do they not want to turn their gas stations into parking lots with a bunch of cars waiting for their half hour of charge time?

Perhaps the reason Michigan only has one Supercharger station is because Michigan has long, cold winters.  Limiting electric car traveling to the summer months.  In fact, if you live in a northern state look for the charging stations some big stores have installed to show how green they are.  Chances are you won’t see a single car at them during the winter.  For when it comes to cold winters gasoline has it all over batteries.  Gasoline provides far greater range.  You can jump-start a gasoline engine in the coldest of winters and then drive home.  And if it’s cold you can crank the heat up to make it feel like summer inside that car.  Something you can’t do in an electric car without sacrificing further range.

The Model T was an improvement over the horse.  But the electric car is just not an improvement over the Model T.  Because a gasoline-powered car is superior to an all-electric car.  For if one was going to travel across a state the Model T would have better odds of getting you where you were going before running out of energy.  And even if you ran out of gas someone could bring a can of gasoline to you so you could drive to the next gas station.  Whereas an electric car would require a tow truck to the next charging station.



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Uninterruptible Power Supply

Posted by PITHOCRATES - February 12th, 2014

Technology 101

The Battery in a Laptop is basically an Uninterruptible Power Supply (UPS)

When working on a personal computer (PC) you’ve probably learned to save your work.  Often.  So if something happens you won’t lose your data.  For there is nothing more frustrating than writing a report off the top of your head without notes only to suffer a power interruption.  And if you didn’t save your work often everything you typed after the last time you did save your work will be lost.  Forever.

Of course if you were working on a laptop you wouldn’t have to worry about losing your work.  Even if you didn’t save it.  Why?  Because of the battery.  Laptops are portable.  We use them often times where there are no power outlets.  Running them, instead, on the internal battery.  Some models even let you change a battery with a low charge to a freshly charged battery without shutting down your laptop.  Which extends the time you can work without being plugged in.

The battery in a laptop is basically an uninterruptible power supply (UPS).  You can work on a laptop while plugged into an AC outlet.  But if someone trips over the cord and pulls it out of the outlet the laptop will switch over to the battery.  And the only way you would know there was a power interruption is if it was yanked off your lap when the person tripped on the cord.  Because thanks to that battery the computer itself never knew there was a power interruption.

The Main Components of an Offline/Standby UPS are a Charger, a Battery and an Inverter

A PC doesn’t come with a built in battery like the laptop.  But we can add one externally.  Which a lot of people have done.  Not only to prevent the loss of data.  But to protect the electronics inside their PC and other sensitive electronic equipment.  Like a monitor.  A cable modem.  A router.  Even a big screen television.  As sensitive electronic equipment can only operate safely in a narrow band of voltages.  And really don’t like things like surges and spikes coming in on the electrical utility line from a lightning strike.  Or under-voltages on hot summer days when everyone in the neighborhood is running their air conditioners.

A UPS can provide a battery backup.  And it can protect your sensitive electronic equipment from surges, spikes and under-voltages.  Which can cause great harm.  Something those surge protected plug-strips can’t protect you from.  They may take a spike or two.  But they are passive devices.  And can do nothing to protect you from an under-voltage (i.e., a brownout).  Only a UPS can.  Of which there are three major types.  Offline/standby.  Line-interactive.  And Online/double-conversion.

An offline/standby UPS is the least expensive and simplest.  The main components inside the UPS are a charger, a battery and an inverter.  It plugs into an AC outlet.  And the devices you want to protect with it plug into the UPS.  If the input voltage (the voltage at the AC outlet) is within a safe range the AC outlet powers your devices.  Also, the UPS controls circuit will monitor the battery voltage.  If it is too low the controls will turn on the charger and it will charge the battery.  When the voltage on the battery is at the level it should be the controls disconnect the charger.  If the UPS controls detect an over-voltage, an under-voltage or a power loss an internal switch disconnects the AC outlet from your devices.  And connects them to the inverter.  A device that converts the DC voltage from the battery into an AC voltage for your equipment.  It will power your devices from a few minutes to up to a half hour (or more) depending on the power requirements of your devices and the battery size.  If the voltage at the AC outlet returns to normal the internal switch will disconnect the devices from the inverter.  And reconnect them to the AC outlet.  If there is a complete power loss you will have time to save your work and safely power down.

The Online/Double-Conversion provides the Best Power Protection for your most Sensitive Electronics

An offline/standby UPS is an efficient unit as it only consumes power when it charges or switches to the battery.  However, switching to the battery every time there is an over-voltage or under-voltage can shorten the battery life.  A problem the line-interactive UPS doesn’t have.  Because it doesn’t switch to the battery every time there is a power fluctuation in the input power.  The line-interactive UPS is basically an offline/standby UPS with an additional component.  An autotransformer.  Which is basically a transformer with a single winding and multiple secondary taps.  If the input power is within the safe range the voltage in equals the voltage out of the autotransformer.  If the input voltage is too high the controls will switch the output to a different secondary tap that will lower the voltage back to the safe range.  If there is an under-voltage the controls will switch the output to a tap that will raise the voltage back to a safe range.  So that these over and under voltages will be corrected by the autotransformer and not the battery.  Which will remain disconnect from the load devices during these autotransformer corrections.  Thus increasing battery life.

The offline/standby UPS is a little more costly but it will have a longer battery life.  And it will also be efficient as it will take minimum power for the controls to switch the taps on the autotransformer.  But if you want the best power protection for your most sensitive electronic equipment you will get that with the more costly and less efficient online/double-conversion UPS.  This UPS is different.  It takes the power from the AC outlet and converts it into DC voltage.  It then takes this DC voltage and produces a pure AC voltage from it.  Free from any voltage irregularities.  Completely isolating your sensitive electronic equipment from the dangers on the electric grid.  For the electrical loads are not normally connected directly to the AC outlet.  They are always connected to the AC output of the inverter.  Which makes this unit the least efficient of the three as it is always consuming power to power the connected loads.

The battery is always connected in the online/double-conversion UPS.  So in a blackout there is no switching required to transfer the loads to the battery. Making for a seamless transition to battery backup.  Of course, sometimes the electrical components inside the UPS malfunction or fail.  In that case the UPS can switch the loads directly to the AC outlet.  Should imperfect power be better than no power.  They will also have an isolation bypass switch.  So you can switch these units directly to the AC source to service the UPS components.  Which may be necessary due to one drawback of the online/double-conversion UPS.  Because the components are always consuming power they generate more heat than the other two types.  Requiring additional cooling to keep these units operating safely.  But they can overheat and breakdown.  Which makes an isolation bypass switch handy to service these while still powering the connected loads.



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Girl sits on Phone in Back Pocket and starts Fire just as Damaged Batteries start Fires in Electric Cars

Posted by PITHOCRATES - February 2nd, 2014

Week in Review

Lithium-ion batteries are a wonder.  But they can be temperamental.  Which you can expect when you put highly reactive chemicals together.  Which is the price of higher energy storage densities.  Danger.  To make that charge last longer in the batteries powering our electronic devices.  And they can only do that by a chemical reaction that produces heat.  Boeing had a problem with their lithium-ion batteries that nearly caught a couple of their new Dreamliners on fire.  Resulting in an FAA grounding of the entire fleet until they found a way to make their batteries safer.  But it’s not just big lithium-ion batteries that can burst into flames (see iPhone catches fire, teen girl burned by Chris Matyszczyk posted 2/1/2014 on CNET).

An eighth-grader in Maine is sitting in class when she hears a pop. Then she notices smoke coming from her back pocket…

The culprit is said to have been her iPhone. Images suggest it had caught fire…

The division chief of the local emergency medical services, Andrew Palmeri, told Seacoast Online that the phone’s battery had “shorted out.” He suggested that the phone had been crushed in the teen’s back pocket. Local fire services are investigating…

Cell phones of whatever brand do catch fire. iPhones have caught fire on planes, just as Droids have exploded in ears.

So lithium-ion batteries can be dangerous.  Despite being the wonders they are.  For these chemical reactions are powerful.  And need to be confined perfectly.  But if you sit on a cell phone you can damage the confinement of those chemicals.  Causing a fire.  Just as accidents in electric cars have resulted in battery fires that have totaled these cars.  Or a faulty charging circuit started a fire overnight while charging in an attached garage.  Starting the house on fire.  Or nearly started a plane on fire.

The greatest hindrance to electric car sales is a thing called range anxiety.  Will I have enough charge to get home?  The answer to this problem is, of course, increasing the charge available in these cars.  Typically with bigger and more powerful batteries.  Which can burn the car to a crisp after an accident damages the battery.  Or debris on the roadway is thrown up by a tire into the battery.  Things that won’t total a gasoline-powered car if they happen.  Because gas is a high-density energy source.  Like these lithium-ion batters.  But it takes a lot more abuse to the gas tank to get it to start a fire.  Which is why electric cars will not replace the gasoline-powered car.  As they provide a far greater range and are safer.  And until the electric car can out do the gasoline-powered car on these two points the electric car will remain a novelty.



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Tesla has made it Possible to drive Cross-Country in an Electric Car

Posted by PITHOCRATES - February 1st, 2014

Week in Review

Tesla has installed charging stations across the country.  You can now drive from Los Angeles to New York City.  As long as you want to take the scenic route and are in no hurry (see Tesla’s 800-mile cross-country detour by Chris Isidore posted 1/30/2014 on CNN Money).

Tesla owners can now drive across the country using the company’s network of charging stations to power their batteries — as long as they don’t mind going about 800 miles out of their way…

Tesla says the route…is…3,400 miles long…

The superchargers provide enough juice in 30 minutes to take a Tesla about 170 miles. There are 32 stations on the route between downtown Los Angeles and New York City, and more than 40 others mostly up and down both coasts.

The Model S, which starts at about $69,000, needs to be charged every 244 to 306 miles, depending on the battery size.

Sounds good.  But for those of us comfortable with ease of traveling with gasoline will not experience that same ease driving from one charging station to another.  Let’s look at this by first looking at a full-size sedan powered by a gasoline-engine.  Like a Ford Taurus.  They can get about 29 miles per gallon on the highway and have an 18 gallon gas tank.  Crunching the numbers for that 3,400 mile trip it will take about 117 gallons of gasoline (3,400/29).  With an 18 gallon gas tank it will take 7 fueling stops to complete the trip (117/18).  Assuming 5 minutes to refuel and another 10 minutes for incidentals (pulling in, pulling out, paying at the pump, waiting for a fuel pump to become available, etc.) that’s 105 minutes (7 X 15).  Or 1.75 hours (105/60).  Adding just under 2 hours to the trip for fueling.

For 32 charging stations to cover that 3,400 miles means they are on average 106.25 miles apart.  So a half-hour quick charge will take you to the next charging station with 170 miles of charge available on your battery.  Assuming 30 minutes to charge and another 15 minutes for incidentals (pulling in, pulling out, waiting for another car to complete their 30 minute charge, etc.) that’s 1,440 minutes (32 X 45).  Or 24 hours (1,440/60).  Adding 24 hours to the trip for charging.  Or a full day.  Or 2 days if you only drive 12 hours a day.  Or 3 days if you only drive 8 hours a day.

Now imagine a world where everyone is driving electric cars.  And there are three cars ahead of you at the charging station waiting for a charge.  Adding an hour and half waiting time in addition to your 45 minute charging stop.  If it was like this at every charging station and you drove 12 hours a day that would add 6 days of traveling to that trip.  Whereas the odds are less likely that you will have to wait for 3 cars ahead of you at a gas station.  Because there are so many more gas stations to go to.

Driving cross-country in an electric car could add 6 days to a 4-day trip.  Making the electric car a novelty at best.  Unless your vacation is all about getting there.  And not about being there.  Where you drive there, turn around and return home.  Because you have no time to spend there due to the time it took to get there.  You could do that.  Or drive a gasoline-powered car.  And do more than just drive on your vacation.



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Magnets, Magnetic Field, Electromagnet, Electromechanical Solenoid, Stator, Armature, DC Electric Motor and Automobile Starter Motor

Posted by PITHOCRATES - January 1st, 2014

Technology 101

(Originally published April 18th, 2012)

Electric Current flowing through a Wire can Induce Magnetic Fields Similar to those Magnets Create

We’ve all played with magnets as children.  And even as children we’ve observed things.  If you placed a bar magnet on a table and approached it with another one in your hand one of two things would happen.  As the magnets approached each other the one on the table would either move towards the other magnet.  Or away from the other magnet.  That’s because all magnets are dipoles.  That is, they have two poles.  A north pole.  And a south pole.

These poles produce a magnetic field.  Outside of the magnet this field ‘flows’ from north to south.  Inside the magnet it ‘flows’ from south to north.  So imagine this magnetic force traveling through the magnet from south to north and right out of the north pole of the magnet.  Where it then bends around and heads back to the south pole.  Something most of us saw as children.  When we placed a piece of paper with iron filings over a bar magnet.  As we placed the paper over the magnet the iron filings moved.  They formed in lines.  That followed the magnetic field created by the magnetic dipole.  You can’t see the direction of the field but it only ‘flows’ in one direction.  As noted above.  If the north pole of one magnet is placed near the south pole of another the magnetic field ‘flows’ from the north pole of one magnet to the south pole of the other magnet.  Pulling them together.  If both north poles or both south poles are placed near each other they will repulse each other.  Because the magnetic field is ‘flowing’ out from each north pole.  Or into each south pole.  The magnets repulse each other because the magnetic field is trying to flow from north to south.  If one magnet was able to rotate this repulsion would rotate the magnet about 90 degrees.  To try and align one north pole with one south pole.  As the momentum pushed the magnet past the 90 degree point the force would reverse to attraction.  Rotating the magnet about another 90 degrees.  Where it will then stop.  Having aligned a north and a south pole.

It turns out this ability to move things with magnetic fields is very useful.  Both in linear motion.  And rotational motion.  Especially after we observed we could create magnetic fields by passing an electric current through a wire.  When you do a magnetic field circles the wire.  To determine which direction you simply use the right-hand rule.  Point your thumb in the direction of the current flow and wrap your fingers around the wire.  Your fingers point in the direction of the magnetic field.  Fascinating, yes?  Well, okay, maybe not.  But this is.  You can wrap that wire around a metal rod.  Creating a solenoid.  And all those induced magnetic fields add up.  The more coils the greater the magnetic field.  That ‘flows’ in the same direction in that metal rod.  Creating an electromagnet out of that metal rod.  If you ever saw a crane in a junk yard picking up scrap metal with a magnet this is what’s happening.  The crane operator turns on an electromagnet to attract and hold that scrap metal.  And turns off the electromagnet to release that scrap metal.

A DC Electric Motor is Basically a Fixed Magnet Interacting with a Rotating Magnet

If that metal rod was free to move you get something completely different.  For when you pass a current through that coiled wire the magnetic force it creates will move that metal rod.  If it’s not restrained it will fly right out of the coil.  Which is interesting to see but not very useful.  But the ability to move a restrained metal rod at the flick of a switch can be very useful.  For we can use a solenoid to convert electrical energy into linear mechanical movement.  As in a transducer.  An electromechanical solenoid.  That takes an electrical input to generate a mechanical output.  Which we use in many things.  Like in a high-speed conveyor system that sorts things.  Like a baggage handling system at an airport.  Or in an order fulfillment center.  Where things fly down a conveyor belt while diverter gates move to route things to their ultimate destination.  If the gate is not activated the product stays on the main belt.  When a gate is activated a gate moves across the path of the main conveyor belt and diverts the product to a new conveyor line or a drop off.  And the things that operate those gates are electromechanical solenoids.  Or transducers.  Things that convert an electrical input to a mechanical output.  To produce a linear mechanical motion.  To move that gate.

Solenoids are useful.  A lot of things work because of them.  But there is only so much this linear motion can do.  Basically alternating between two states.  Open and closed.   In or out.
On or off.  Again, useful.  But of limited use.  However, we can use these same principles and create rotational motion.  Which is far more useful.  Because we can make electric motors with the rotational motion created by magnetic fields.  The first electric motors were direct current (DC).  And included two basic parts.  The stator.  And the rotor (or armature).  The stator creates a fixed magnetic field.  With permanent magnates.  Or one created with current passing through coiled wiring.  The armature is made up of multiple coils.  Each coil insulated and separate from the next one.  When an electric current goes through one of these rotor coils it creates an electromagnet.

So a DC electric motor is basically a fixed magnet interacting with a rotating magnet.  Current passes to the rotor winding through brushes in contact with the armature.  Like closing a switch.  Current flows in through one brush.  And out through another.  When current goes through one of these rotor coils it creates an electromagnet.  With a north and south pole.  As this magnetic field interacts with the fixed magnetic field produced by the stator there are forces of attraction and repulsion.  As the ‘like’ poles repel each other.  And the ‘unlike’ poles attract each other.  Causing the armature to turn.  After it turns the brushes ‘disconnect’ from that rotor wiring and ‘connect’ to the next rotor winding in the armature.  Creating a new electromagnet.  And new forces of repulsion and attraction.  Causing the armature to continue to turn.  And so on to produce useful rotational mechanical motion.

An Automobile Starter Motor combines an Electromechanical Solenoid and a DC Electric Motor

Everyone who has ever driven a car is thoroughly familiar with electromechanical solenoids and DC electric motors.  Because unlike our forefathers who had to use hand-cranks to start their cars we don’t.  All we have to do is turn a key.  Or press a button.  And that internal combustion engine starts turning.  Fuel begins to flow to the cylinders.  And electricity flows to the spark plugs.  Igniting that compressed fuel-air mixture in the cylinder.  Bringing that engine to life.

So what starts this process?  An electromechanical solenoid.  And a DC motor.  Packaged together in an automobile starter motor.  The other components that make this work are the starter ring gear on the flywheel (mounted to the engine to smooth out the rotation created by the reciprocating pistons) and the car battery.  When you turn the ignition key current flows from the battery to the electromechanical solenoid.  This linear motion operates a lever that moves a drive pinion out of the starter (while compressing a spring inside the starter), engaging it with the starter ring gear.  Current also flows into a DC motor inside the starter.  As this motor spins it rotates the starter ring gear on the flywheel.  As combustion takes place in the cylinders the pistons start reciprocating, turning the crankshaft.  At which time you let go of the ignition key.  Stopping the current flow through both the solenoid and the DC motor.  The starter stops spinning.  And that compressed spring retracts the drive pinion from the starter ring gear.  All happening in a matter of seconds.  So quick and convenient you don’t give it a second thought.  You just put the car in gear and head out on the highway.  And enjoy the open road.  Wherever it may take you.  For getting there is half the fun.  Or more.

Electric motors have come a long way since our first DC motors.  Thanks to the advent of AC power distribution and polyphase motors.  Brought to us by the great Nikola Tesla.  While working for the great George Westinghouse.  Pretty much any electric motor today is based on a Tesla design.  But little has changed on the automotive starter motor.  Because batteries are still DC.  And before a car starts that’s all there is.  Once it’s running, though, a polyphase AC generator produces all the electricity used after that.  A bridge rectifier converts the three phase AC current into DC.  Providing all the electric power the car needs.  Even charging the battery.  So it’s ready to spin that starter motor the next time you get into your car.



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Leyden Jar, Electric Charge, Galvanic Cell, Voltaic Pile, Anions, Cations, Daniell Cell, Zinc-Carbon Battery and Alkaline Battery

Posted by PITHOCRATES - December 25th, 2013

Technology 101

(Originally published December 19th, 2012)

Luigi Galvani made a Dead Frog’s Leg Twitch when he hit it with the Electric Discharge Shock from a Leyden Jar

The field of electricity took off with friction generators.  Dragging something across another substance to produce an electrical charge.  Like sliding out of your car on a dry winter day.  Producing an electric discharge shock just before your hand touches the metal door to close it.  Atoms in materials are electrically neutral.  There are an equal number of positive particles (protons) and negative particles (electrons).  Friction can transfer some of those electrons from one surface to another.  Leaving one surface with a net positive charge.  And the other with a net negative charge.  These charges equalize after that electric discharge shock.  Returning the atoms in these materials to an electrically neutral state.

Further exploration of static electric charge led to the development of the Leyden jar.  A precursor to the modern capacitor.  A glass jar with metal foil on the inside and outside of a glass bottle.  The foil sheets act as plates.  The glass as a dielectric.  An electrode attached to one plate received an electric charge from a friction generator.  The other plate was grounded.  The dielectric helped the plates hold an electric charge.  Benjamin Franklin did a lot of experiments with the Leyden jar.  He noted how multiple Leyden jars could hold a greater charge.  Commenting that it was like a battery of cannons.  Giving us the word battery for an electrical storage device.

Luigi Galvani made a dead frog’s leg twitch when he zapped it with the electric discharge shock from a Leyden jar.  Furthering his experiments Galvani found that he could reproduce the twitching by placing the frog’s leg between two different types of metals.  Creating a galvanic cell.  Which created an electric current.  Alessandro Volta recreated this experiment while substituting the frog tissue with cardboard soaked in salt water (an electrolyte).  Creating the voltaic cell.  Piling one voltaic cell onto another created a Voltaic Pile.  Or as we call it today, a battery.

A Daniell Cell created a Current by Stripping away Electrons from one Electrode and Recombining them on Another

What Galvani and Volta discovered was a chemical reaction that caused an electric current.  The Voltaic Pile, though, had a limited life.  To improve on it John F. Daniell added a second electrolyte.  Creating the Daniell Cell.  Which extended the life of a battery charge.  Allowing it to do useful work.  Becoming the first commercially successful battery.  Powering our first telegraphs and telephones.  Even finding their way into our homes operating our doorbells for a century or so before Nikola Tesla brought alternating current electric power to our homes.

The chemical reaction in a Daniell Cell created an electric current by stripping away electrons from one metal electrode in a solution (anode oxidation).  And recombining electrons onto another electrode of a different metal in a different solution (cathode reduction).  Each electrode is in an electrolyte solution.  In a copper-zinc Daniell Cell the anode is typically in a solution of zinc sulfate.  And the cathode is in a copper sulfate solution.  A salt bridge or porous membrane connects the different electrolytes.  When an electric load is connected across the ‘battery’ electrodes it completes the electrochemical system.

Each electrolyte contains ions.  Atoms with a net positive or negative charge.  Positive ions are cations.  Negative ions are anions.  The cathode attracts cations.  Where they combine with free electrons to return to a neutral state.  The anode attracts anions.   Where they give up their extra electrons to return to a neutral state.  This chemical activity dissolves the zinc electrode.  And deposits copper on the copper electrode.  (This electrolysis is the basis for the metal plating industry.)  It is the dissolving of the anode that gives up electrons that travel from one electrode through the electric load to the other electrode.  Doing work for us.  By lighting our flashlights.  Or powering our portable radio.  When the anode dissolves to the point that it cannot give up anymore electrons the chemical reaction stops.  And we have to replace our batteries.

An Alkaline Battery will produce more Useable Power and have a longer Shelf Life than a Zinc-Carbon Battery

Of course, the zinc-carbon batteries we use for our flashlights and radios are not wet cells.  They’re dry cells.  Instead of an electrolyte solution the common battery is made up of dry components.  The zinc anode is the battery casing.  Just inside the battery zinc casing is a paper layer impregnated with a moist paste of acidic ammonium chloride.  This separates the zinc can from a mixture of graphite powder and manganese (IV) oxide (pyrolusite).  In the center of the battery is a carbon rod.  The zinc casing is the negative electrode (anode) and the carbon rod is the positive electrode (the cathode).  The chemical reactions are the
same as they are with the wet cell.  The zinc casing (the anode) becomes thinner over time.  When holes begin to appear the battery will leak creating a sticky mess.  As you no doubt experienced when taking an old set of batteries out of a flashlight that hasn’t been used in years.

An alkaline battery looks similar to a zinc-carbon battery.  But there are many differences.  Instead of an acidic ammonium chloride electrolyte an alkaline battery uses an alkaline potassium hydroxide electrolyte.  The little nub (positive terminal) on top of the battery does not connect to a carbon rod in the center of the battery.  It connects to the outer casing.  Inside this casing is a mixture of graphite powder and manganese (IV) oxide (pyrolusite).  Then a barrier to keep the anode and cathode materials from coming into contact with each other.  But lets ions pass through.  On the other side of the barrier is the anode.  A gel of the alkaline potassium hydroxide electrolyte containing a dispersion of zinc powder.  In the middle of the battery is a metal rod that acts as a current pickup that connects to the bottom of the battery (the negative terminal).

Alkaline batteries are the most popular batteries today.  Because they have a higher energy density than a zinc-carbon battery.  Meaning that an alkaline battery will produce more useable power than a comparable sized zinc-carbon battery.  And they have a longer shelf life.  But with these benefits comes costs.  They can leak a caustic potassium hydroxide.  An irritant to your eyes and skin.  As well as your respiratory system.  As they age they can produce hydrogen gas.  Which can rupture the casing.  If a battery leaks potassium carbonate (a crystalline structure) can grow.  If this crystalline structure reaches the copper tracks of a circuit board it will oxidize the copper and metallic components.  Damaging electronic devices.  But the benefits clearly outweigh the risks.  As about 80% of all batteries sold in the U.S. are alkaline batteries.




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