The population time bomb

I was a teenager in the 1970s and I had a poster from a lithograph (shown above) on my wall that was simply titled: "Overpopulation".  It was painted by John Pitre in 1973 and I remember spending hours looking at all the details of the thousands of nude or partly clothed humans in the ruins of this painting.  It is evocative of the third panel in Hieronymus Bosch's tryptych: "The Garden of Earthly Delights".  It presents a very dystopian view of the future of humanity and it affected my world view profoundly.

Population growth

In the 1970s the ecology movement was just getting started by the post-hippies and part of the dialogue centered around population growth and a concern for an unsustainable amount of people living on the planet.  What continues to surprise me is how rarely we talk about overpopulation in the context of Climate Change now.

The chart above dates from June 2010 and estimates that we will have more than 9 billion people on the planet by 2050.  There are various estimates as to how many people become unsustainable, and some say we have already passed that point.  What many of the estimates don't take into account is the potential crash of agriculture as a result of climate change.  This would make even our current population completely unsustainable.

Looking at the world population chart over the last two centuries, we see the classic hockey stick chart that evokes a similar chart representing CO2 in parts per million.  It's no accident that the two charts coincide.  Between 1999 and 2011, global population increased by a billion people.  Most of this population increase was in developing nations where individual carbon footprint is somewhat lower.  While population growth is likely to taper off eventually, we may already have crossed the tipping point.

Extinction versus population

Every twenty minutes, the human population grows by over 3000. That’s the same amount of time that it takes for another plant or animal species to become entirely extinct.  Yes, the sixth extinction has already begun!  From pollinating our crops, to purifying our water, providing fish to eat or fiber to weave, we are dependent on biodiveristy. Ecosystems can only continue to provide things for us if they continue to function in a harmonious balance.

Carrying Capacity

A 2014 study by the World Wildlife Fund found that the global human population exceeds the planet's biocapacity, and that it would take the equivalent of 1.5 Earths of biocapacity to meet our current demands.  So it comes down to a balance of population versus consumption, or more aptly put, over-consumption.  Studies would seem to indicate that the maximum carrying capacity for humanity is around 7.7 billion people, and as of this writing we are at 7.4 billion people.  But it's not just the birth rate that contributes to the issue, it's increased life expectancy.  People are living an average of 35 more years than they were 100 years ago.  So in essence we have already crossed the tipping point - or we will very shortly.  Here is a web page that tracks population and a lot of other relevant statistics: http://www.worldometers.info/world-population/.

Finite resources

By continuing to use up finite resources, extract and burn fossil fuels, and destroy wildlife habitat, we are moving inexorably towards a potential extinction for humanity.  

English economist Thomas Malthus (1766-1834) proposed that the world rate of population growth was exceeding the development of food supplies.  Malthus proposed that human population was growing exponentially, while food production was growing linearly.  Children born now will be growing up in a vastly changed world in which food scarcity is likely to become a significant issue as they become adults.  It is inevitable that wars will be fought over resources such as freshwater, arid land, and even dry land as the ocean levels rise.

There is a Chinese curse: "May you live in interesting times".  There is no question in my mind that there are interesting times ahead.   The real question is what can we do about it now to create a survivable scenario for humanity.  I'm doing what I can, but it often feels like I'm swimming alongside the Titanic trying to push it away from the iceberg.

Climate Change and the Carbon Bubble

Image links to Andrew C. Revkin's article for the NYT from May3, 2013

Readers of my blog and website understand that I am deeply concerned about climate change and its impacts on the future of humanity.  I have been struggling with a good way to frame all of this into the larger context of geopolitics when I came across this excellent article:

Trump, Putin and the Pipelines to Nowhere

You can’t understand what Trump’s doing to America without understanding the “Carbon Bubble”

I strongly encourage you to take a few minutes to sit down and read this article because it lays out the big picture very clearly.  For instance, here is what he has to say about the carbon bubble:

"This means we must limit the total amount of CO2 and other greenhouse pollution we put into the sky: we have to meet a “carbon budget.” To do meet that budget, we have to radically cut greenhouse gas emissions — burning way less oil, coal and gas — in the next two decades, and set the global economy on a steep path to zero emissions.

If we can’t burn oil, it’s not worth very much. If we can’t defend coastal real estate from rising seas (or even insure it, for that matter), it’s not worth very much. If the industrial process a company owns exposes them to future climate litigation, it’s not worth very much. The value of those assets is going to plummet, inevitably… and likely, soon."

From my perspective, if Trump's oil oligarchy cabinet of horrors fails to slow our use of fossil fuel, he will be directly responsible for more Climate Change related deaths than Hitler or any other major world war.

Revised charging strategy for the 2017 Volt

I am still discovering differences between the 2012 Chevy Volt and the new 2017 model that I leased a few weeks ago.  Previously, I wrote a detailed comparison of the two vehicles, but now I want to delve into the difference in the way these two vehicles utilize power from the charging station.

The first difference I noticed is that the new one draws 500 W more power in order to charge the 15% larger capacity battery more quickly from my level II charging station.

I am currently using a 240 V JuiceBox charging station that I installed myself and it can fully charge the new Volt in about 4.5 hours.  This is convenient when I have to make multiple long trips within any given day.  Years ago, I installed a live-to-the web energy monitoring system that show charts of the last 24 hours of energy drawn from the charging station on my web page.  

With the 2012 model, I noticed that the vehicle would draw power in brief bursts even after the vehicle was fully charged.  It would only do this during the winter after temperatures got below freezing.  In fact the further the temperature dropped below 20°F the more often it would draw power.  My assumption is that this was all about keeping the battery warm.  As I understand it if a lithium polymer chemistry battery is below freezing when you draw significant power from it, the battery can be damaged.  So GM engineers have implemented systems to ensure that the battery does not freeze.  A warm battery is a happy battery!  The combined chart above shows this clear correlation between temperature and these short energy draws.

click the image to see current charts at the bottom of my Chevy Volt web page

The 2017 model seems to draw power on a consistent basis in short bursts irrespectful of temperature.  The charts above (from mid December) show that the temperature dropped down to around 7°F and peaked around 35°F while the maintenance charge intervals remain the same.  Note that there is a full charging cycle at the left edge of the chart and two short vehicle charging cycles to the right.

The resolution of my data monitor is not fine enough to resolve details of the brief energy draws because it only takes a reading every 10 minutes, so I hooked up a data logger to do a deep dive on exactly what is going on.  The chart above shows a 12 hour period sampling power every second with a fully charged vehicle and temperatures hovering around freezing.

Zooming in on the left side of the chart above I discovered that the 2017 Volt often starts out by drawing 4000 W and then tapers off.

Zooming in even more to the center of the top chart you can see a single cycle that starts at 4 kW, drops out briefly and then holds at about 4 kW for just over nine minutes, eventually tapering off a little.  This dropout and tapering off varies from cycle to cycle for reasons not yet apparent to me.


I am seeing around 9 of these 9+ minute cycles every 12 hours, so a fully charged vehicle is drawing 4 kW for a combined total of around 180 minutes every 24 hours.  That adds up to around 81 kWh per month!  (For reference, the 2012 Volt needs about 13 kWh for a full charge, and the 2017 needs around 15 kWh.)

Looking at a 4 day data log of charging Watts vs temperature, there is no clear correlation between temperature and charging power used for battery maintenance.  In fact energy draws seem less frequent as temperature increases which is odd.


The average cost per kilowatt hour in the US is $.10, so this battery maintenance energy is costing around $8 per month if it remains very cold.  Here in Maine I pay around $.13 per kilowatt hour for energy that is 30% renewable so I'm paying about $10.50 per month to maintain the battery.  (Actually for most of the year my electrical energy comes entirely from my 5 kW solar array, so there is no cost to me).

Another way GM engineers are squeezing more range out of the new, 15% larger battery is that they are using more of its capacity.  Based on readings taken from my DashDAQ-XL performance monitor I learned that the 2012 utilized from 22% to 87% state of charge, while the 2017 uses from 14% to 90% state of charge.  So the new Volt is using about 11% more capacity from the battery.  When I met the GM battery engineers back in 2011, they sounded quite paranoid about not abusing the battery in order to give it plenty of life.  I'm guess that they learned a lot from the 2012 battery and applied those lessons to a different battery management strategy for the 2017 model.

The main lesson to be learned for those of us driving this amazing vehicle is that it is essential to leave it plugged into the charging station if you live in a cold climate to protect the battery.  If it is not plugged into the charging station it will draw down battery energy, and even resort to starting the gasoline engine in order to utilize heat from the coolant to maintain a safe battery temperature.

Climate change has crossed the tipping point

The greatest threat to humanity

I am very committed to living sustainably, and this commitment arises from my deep concern about the future of humanity in the face of accelerating climate change.  To put it simply, there is no greater threat to humanity.  Mainstream media and even the better web sources that report responsibly on climate change are not covering the rapidly changing news.  It is quite clear to me that humanity has already passed the tipping point this summer when CO2 in the atmosphere exceeded 400 ppm and that global climate change is accelerating, and will continue to do so at a very rapid rate.  Yes, I mean that the rate of change is increasing.  Climate scientist's predictions are generally  conservative, but there are a few who have been sounding the alarm in recent years.

Arctic Science

I have been following the blogs of several climate science researchers (see below) who have written posts about how the warming planet is melting the Arctic ice caps and causing accelerated feedbacks resulting in massive releases of methane (known as the Methane Time Bomb) from the Arctic Ocean and tundra.  Methane is 30 times more potent as a greenhouse gas than CO2.  But now new science has discovered that as the Arctic soil warms, microbes in the soil are now beginning to release massive amounts of CO2 creating yet another feedback that accelerates global warming.  This has been an unanticipated source of CO2 not used in calculations and climate change models to date.

Agriculture

Bloggers are suggesting that agriculture throughout the world could crash within 20 years due to extreme drought and other effects thus beginning the start of a huge human die off.  Even if these guys are off by 20 or even 40 years, the situation is dire, humanity may well be on a path to extinction.  And it's not just us: since 1900, birds, mammals, reptiles, amphibians and fish died 72 times faster than normal.

Species Extinction

Nearly half the species on the planet are failing to cope with global warming the world has already experienced, according to an alarming new study that suggests the sixth mass extinction of animal life in the Earth’s history could take place in as little as 50 years.

Knowledge is power

Many of us older folks (I'm 61 as I write this in 2016) will not live long enough to see the worst outcome of this crisis, but future generations will.  So I feel it is important for us to be aware and knowledgeable about the situation so that we can advise those who come after us and suggest that they now begin preparing for the worst.  Anyone alive now who is less than 40 years old may be living in a vastly changed world in which food will eventually become extremely expensive and/or largely unavailable.  Life as we know it will be fundamentally changed.

Ocean level rise

Consider for example that most climate scientists agree that the ocean levels will rise by at least 6 feet by the end of the century.  As our understanding of climate feedbacks increases this estimate may be considered quite conservative.  This is sufficient to completely submerge much of Bangladesh to the point where it becomes uninhabitable.  And of course many coastal cities and island nations will need to be abandoned and that point.  This will affect millions of people and force them to being climate refugees.  For example more than 1 million Syrians are now refugees due to drought triggered by climate change and these large droughts are going to get bigger and worse in the future.  Thousands of people are already dying as a direct result of climate change.
 

What can we do? 

Well, some of us are already doing the best we can by living sustainably, modeling the change we want to see in the world, and acting socially and politically to raise awareness and affect change.  It is important not to be paralyzed by this concern and to continue to do as much as we can - especially in the face of the current political climate.  Addressing climate change needs to be part of our daily dialogue.  I recall a bumper sticker from the 1970s that said: "If you're not part of the solution, you're part of the problem".  Everything that we can do today no matter how large or small will have an impact on the future.  I have heard that Native Americans always made major decisions with a view to seven subsequent generations.  I hope that humanity has the luxury to survive for another seven generations.  I am an irrepressible optimist and certainly hope that we will figure this out, but it will take the concerted action of all of humanity to wake up and affect change as soon as possible.  We cannot continue with business as usual.  If I were a young person today, I would be giving very serious thought about whether it would be wise to bring a child into this changing world.  Population is a big contributor to the problem.

References

Arctic News blog
This one is written by Sam Carana in plain easy-to-read language with beautifully prepared graphics that explain everything very clearly.  I urge you to sit and take the time to read through this blog and share it with others.  Sam ends every blog post with this line:  "The situation is dire and calls for comprehensive and effective action as described in the Climate Plan."
Robert's Scribblers blog
Robert quotes a number of climate scientists who are all saying that we have passed the point of no return.  He goes on to explain in considerable detail in clear easy-to-read language what is going on.  The final line in his most recent blog is: "In other words, even the optimists at this time think that we are on the cusp of runaway catastrophic global warming. That the time to urgently act is now."


Arctic Sea Ice Collapse
Blog post on Weather Underground summarizing the issue and predicting a complete loss of all Arctic sea ice in the foreseeable future.  The impacts of losing the polar icecap are truly frightening.

NASA Global Climate Change

The scientific consensus updated frequently.

Learn more and share

Thank you for taking the time to read this, and if you want to dig deeper please follow the links embedded throughout my text.  If you have read this far please consider sharing this with your friends - particularly young people.

LED brake + turn light upgrade for my 2017 Chevy Volt

When a friend of mine bought a used Prius several years ago, he told me that the first upgrade he did was to replace the incandescent brake lights with LEDs.  His reasoning was that LEDs light up a lot faster than filament lamps providing an earlier warning to someone behind that he is braking.

I was surprised to find that my new 2017 Chevy Volt still had old-style incandescent lamps, so I decided an upgrade was in order.  But first some geekery!

I wanted to quantify exactly how much quicker LEDs light up than incandescent lamps so I set up a bench test to compare the two.  

I connected each style of lamp to a 12 V battery with a switch and then used my oscilloscope to look at the switched power (yellow) and the amount of light as measured using a photocell (blue trace).  What I learned was that incandescent taillights take 80-100 ms to reach full brightness whereas LEDs come on almost instantaneously (50 µs = 0.05mS).  If you are traveling at 60MPH (88ft/sec.), 80mS is equal to about 7 feet.  Clearly this could be a life-saving difference at speed on a freeway.

brake and turn lamps original vs LED

My go-to source for all things LED is superbrightLEDs.com because they have excellent selection tools to help you find exactly the lamp you need for your vehicle or any other application.  I quickly found the LEDs I was looking for and decided to also get some turn indicator lamps as well.  So for less than $40 I was able to replace all four lamps in the rear of the vehicle.

The 2017 Chevy Volt manual clearly shows (on p.261) how to access the lamps by removing two Torx screws and one Philips screw.  Then you have to pull the tail lamp assembly forcefully back until it snaps free.  

Each lamp is accessed by twisting counterclockwise to pull the socket out.  The lamps simply pull out of the socket and the new ones push in, although the new lamps required a lot of force to get into the socket.

Here is the new LED in the socket ready to be inserted in the assembly.  Unfortunately, the new lamp was very slightly larger than the old one and would not go in the hole in the housing.  So I used my Dremel tool to open up the hole very slightly and it went in just fine.

After I had installed both lamps on one side It was easy to see the difference and how quickly the lamp switches on and off in the turn signals. unfortunately, the turn signal started to hyper flash.  This is a condition where the vehicle responds to the lower power draw of the LED light and starts to blink very quickly.  The solution is to install a Load Resistor Kit from superbrightLEDs.com to trick the vehicle into thinking there is a higher load on the circuit. 

Hopefully I'm never in a situation where I am braking hard on a freeway with someone following closely behind, but I feel that this simple upgrade is a nice performance and safety improvement for the vehicle.

If you are considering a similar upgrade, be advised that all third taillights utilize LEDs, so they illuminate almost immediately compared to the two other brake lights, so you do have the advantage of at least one LED brake light in place in recent model vehicles.  I just like the enhanced response time and visibility.

Why I live as sustainably as I can

Since 2001, I have been doing my best to live as sustainably as I can.  There are several reasons for my commitment.

1.

I'm an engineer dammit!  I enjoy the challenge of using technology to reduce my carbon footprint.  This includes increasing the efficiency of my home and workshop, installing renewable energy systems such as solar power, water heating and building heating and driving a state-of-the-art electric vehicle.  And as a geeky engineer, I choose to monitor and share data from all of the energy efficiency and renewable energy systems that I have installed on  my website. Here are some links to various pages on my site with live data feeds
●Solar electric power system - live performance

●Solar domestic water heater - live temperatures

●Solar building heating system for my workshop - live temperatures

●Heat recovery ventilation system - live temperatures

●And much more on my Living Sustainably page

I also designed and manufacture a line of products designed to improve the performance of solar thermal heating systems.

2.

I'm also an artist and cultural creative.  As such I tend to see outside the box and live a life unconstrained by convention.  As an avid reader of science fiction, I tend to view the world through the lens of an imaginary alien anthropologist and this perspective informs many of my opinions and decisions.  An alien visiting planet Earth for the first time would be truly appalled at the massive scale of devastation we are wreaking on our ecosystem.

3.

Last, but by no means least, I am deeply concerned about the impact of climate change.  I hope that by modeling a sustainable lifestyle that I am demonstrating a viable low carbon footprint existence for humanity.  I look at young people today and have great concern for their future and all generations to come.  I have heard that Native Americans always made decisions with a view to the following seven generations, and that is the way that I choose to operate as well.

Wake-up time.

It is clear to me that the earth has already crossed the tipping point and climate change is accelerating so rapidly that the impacts are already being felt all over the world.  All we can do it this point is to try to slow things down.  It is only going to get worse and all the international climate accords are too little and too late.  Anyone who chooses to pay attention will see climate related news almost every day:
increased severe weather events
shrinking Arctic ice cover
Climate change in general
epic droughts
raging wildfires
frequent coastal flooding due to ocean level rise
plant and animal species extinctions
coral reefs dying


The thing that most surprises me is how few people are truly acting to avert this disaster in a daily conscious way.  I am both saddened and angered by the failures of the family of humankind.  It appalls me that there are people who "don't believe in climate change", this is like saying that you don't believe the sky is blue.  It is not a matter of opinion, the facts are plain and clear.  We are all in this together regardless of nation, race, ideology, religion or identity.  This is the greatest crisis ever to face humanity and we all need to wake the heck up and contribute.  It is not enough to do the token gestures of recycling and composting etc.  It is time to reach deep into our hearts and wallets and make commitments to reduce our carbon footprints at every opportunity.  Almost every time you make a purchase, you are voting for or against a sustainable future for humanity.

For myself, I have found the whole process of implementing renewable energy and technology to be rewarding.  For example,I actually look forward to getting my electric bill which usually shows an energy surplus for 6 or 7 months of the year for which I am later credited.  I am also enjoying driving my 2017 Chevy Volt electric vehicle which is powered largely from free solar energy.  It is an amazing and fun vehicle to own and operate and I use less than 60 gallons of gas per YEAR to drive in "range extended" mode at over 40 miles per gallon. 

Perspective.

Every single astronaut who has had the opportunity to look down at our little blue marble is profoundly impacted by the experience.  They all describe it as a spiritual transformation in which they see the whole world as one without boundaries.  They talk about being overwhelmed by a feeling of love as if the whole planet were their own child.  Click here or on the image above to see a live video feed from the International Space Station and just sit with it for a while. We live on the surface of a beautiful and unique planet.  Humanity cannot survive without a viable ecosytem, but the planet will continue with or without us.

Upgrading from 2012 to 2017 Chevy Volt

I have been wildly enthusiastic about the Chevy Volt since before it went into production and acquired my 2012 model as soon as I could afford to.  I have been completely thrilled with the car and believe that it is the ideal electric vehicle since it cleverly addresses the "range anxiety" issue with its internal gas powered "range extender" generator that allows you to keep driving at 43mpg once the electric battery has been used up.

My dealer (GoodwinsChevrolet) here in Brunswick, Maine made me an offer I could not refuse which was to trade in my old Volt for a very affordable three-year lease on the all new redesigned 2017 model (base price US$33,170).  They graciously allowed me to park both vehicles side-by-side so I could do a detailed comparison review.  GM have redesigned the vehicle from the ground up, and while there is a strong family resemblance, there are fundamental differences that make for significant improvements in performance, functionality and styling.  Personally, I find the new exterior style lines to be much improved.  The GEN 1 design ran from 2012 through 2016.

Sadly GM have discontinued production of the Volt as of March 2019.

The 2012 was really fun to drive and the new model is even more fun with it's crazy fast acceleration and ground hugging performance.  It is also very comfortable on long trips.

Driving Experience

Overall, the GEN 2 vehicle is 250 pounds lighter which translates into a more nimble feel which dramatically increases the 0 to 30 acceleration feel.  The 0 to 30MPH acceleration time has been reduced from 3.1 to 2.6 seconds while 0 to 60 mph performance has improved from 9 to 8.3 seconds.  From a performance standpoint, the low-end acceleration is quite thrilling, the vehicle burns rubber from a standing start if you floor it even in "normal" mode.  This was not even possible in the GEN 1 design.   But more useful is that the EPA rated range has been extended from a maximum of 37 to 53 miles, and I am hearing that  people are getting a range up in the mid-60s with careful driving.  Using MAX climate control in cold weather, I'm seeing a range in the mid 40's.  For someone like me who does mostly local driving to towns up to 15 miles away, this means I will be using gas much less.  In previous years I have used  between 40 and 60 gallons per year - mostly for longer trips.

 

The Gen 2 is noticeably quieter, road and tire noise is much lower due to quieter tires and an improved transmission that is 15% more efficient.  It also makes a lot less funny little mechanical pump noises because the hydraulic brakes pressurize on demand rather than at randomized intervals and the climate control and charging coolant systems seem to be quieter too.  

One does not notice it as a driver, but they have added an electronically generated "Pedestrian Safety Signal" that activates only under 20 mph to warn nearby pedestrians that the vehicle is running.  It is a peculiar sound that is hard to describe - it's kind of a hissing sound - and it is just noticeable enough to be audible without being annoying.  They have removed the "annunciator" button on the left stalk - when pressed the horn would emit a "bip-bip-bip" sound and I rather liked that feature because it was a pleasant way to advise neighbors that I was sneaking up on them on my quiet country road.

regen on-demand paddle

Something I am just beginning to get use to is the new Regen on Demand™ paddle on the left side of the steering wheel.  While I normally drive in "L" mode to optimize regeneration while slowing ("D" mode completely disables regenerative braking via the accelerator pedal), this paddle adds a whole another layer.  (To be clear for the uninitiated "L" mode is NOT a gear, it simply engages the regenerative braking function). Basically you learn to use it as if it were a brake pedal and the vehicle slows much more dramatically when you pull the paddle towards the steering wheel.  It's difficult to convey the difference in experience, but suffice it to say I am using the paddle in place of braking when coming to a stop as often as possible to gain the regenerated energy and increase driving range.   Incidentally the paddle does engage the brake lights.

This feature is a mixed blessing because it means that the rear disc brakes are almost never used.  I had to replace the rear brake discs on my 2012 Volt after only 40,000 miles because they had rusted to the point where they would not pass inspection.  The dealer's service tech explained that I should get the vehicle up to 50 mph or so on a quiet road, drop it in neutral and brake very hard at least once a week to make sure the disc brakes operate forcefully enough to clean out any rust build up.  I also ride the brake when driving very slowly down my road for the first 100ft and I can hear the brakes getting quieter as I do this as the rust buildup cleans off.

 

Tech details

charging data from my old and new vehicle

In order to charge the larger battery in less time the vehicle is drawing an additional 500 W from my 240 V JuiceBox EV charging station.  A full charge takes a nominal 4.5 hours to top up the 18.4 kWh battery (upgraded from 16 kWh).  Charging from 120 V is expected to take 13 hours at 12 Amps.

 

The new battery has 15% more power while weighing 30lb less due to battery chemistry improvements, an 8% decrease in weight.  Battery technology keeps improving, and the new battery cells are 20% more efficient allowing GM to reduce the number of cells in the battery by 96.

It seems that another way they are getting more power out of the battery is by using more of its capacity.  Based on readings taken from my DashDAQ-XL performance monitor I learned that the GEN 1 utilized from 22% to 87% state of charge, while the GEN 2 uses from 14% to 90% state of charge.  So the new Volt is using 11% more capacity from the battery.

I have also noticed that the GEN 2 draws power from the charging station in frequent brief bursts, presumably to maintain the battery within a safe operating temperature range.  The chart above shows two days of energy from my charging station while temperatures varied from just below freezing  to the mid-40s Fahrenheit.  Those brief spikes represent periods of less than 10 minutes with an energy draw ranging from a few hundred Watts to about 2300 W.

The old 1.4 L gas engine (originally from one of their other models) has been replaced with a new 1.5 L engine.  This allows it to generate 75 kW, a 33% increase over the old 50 kW generator making the engine much more efficient.  This is why the "range extender" mode has increased from an EPA rated 37 mpg to 42 mpg or so.  The new engine can also use regular gas rather than premium which is a nice bonus.  In practice I used to get a nominal 40 mpg in the GEN 1 on long trips, and I'm seeing closer to 43 mpg in the 2017 model.  The engine seems to surge to high RPMs of 4000RPM more often in the Gen2 which is slightly annoying and very noticeable when leaving a stop in city traffic.

The transmission in the Volt is a very complicated affair incorporating planetary gears and clutches to connect the two electric motors (known as the MGA and MGB) and the gas engine to the drive train.  Click here if you really want to know more.  It has been completely redesigned to be 12% more efficient and also noticeably quieter.  In my 2012, I used to notice a slight whirring sound at slow speeds with the window open, and that is no longer as noticeable.

The stock low rolling resistance Goodyear tires from the GEN 1 have been replaced with slightly less efficient Michelin tires with a net reduction in road noise and no noticeable trade-off in performance.  The recommended tire pressure is 36 lb, but I'm inflating them to 38 lb to try and improve efficiency slightly.  My stock 2012 tires wore out after about 30,000 miles which was very disappointing.  I upgraded to Continental low rolling resistance tires that are rated for 70,000 miles, but as they aged in they seemed to become louder and louder to the point where it was almost like I was driving with heavy snow tires.  In a vehicle this quiet you really notice road noise.

Exterior

The funky rubber air dam is scaled down and tucked underneath  in the new model and the front grill looks a lot more attractive.

The rear spoiler is much better integrated into the visual aesthetic.  The original spoiler felt like a cheap plastic add-on and road grime would build up underneath of it.  I also think the taillight design is much more attractive.

The headlight design is a little more attractive.  But the significant improvement is in the quality and brightness of the headlights. 

The GEN 1 used a single relatively dim halogen light with a beam that was not wide enough to light the sides of the road.  Driving on rural blacktops at night was not a good experience.  A mechanical shutter blocked the light for the low-beam.  The 2017 model uses very bright white LEDs with a much wider light pattern and the high-beam adds in a bright (warmer toned) halogen.  Overall, the headlights are a vast improvement.

The backup light in the GEN 1 was a single light down in the bumper for European compliance.  There are now two normally placed backup lights in the GEN 2.  

Surprisingly, all of the rear lights including turn and taillights are still incandescent, I would have expected LEDs by now.  I like the swooping curves in the new model though.

The charge port no longer requires that you unlock it by pressing a button on the armrest, you just press it in to click release like a standard gas tank.  This requires a small behavior change because with the GEN 1 Volt one got use to automatically turning the power off and then pressing the button to open the charge port when coming home to connect it to your home charger.  Now you just turn off the vehicle then step outside and click open the port and connect the charge plug.

I like the chrome detailing on the door handles and note that the mechanical key slot has been moved to the bottom surface where it is not visible, and the key must be inserted vertically into the concealed slot in the absence of a functioning remote. 

The key can be completely removed from the keyfob in the new design - The GEN 1 keyfob key flipped out like a switchblade.

I had replaced the original factory wire antenna with a Stubby Antenna because it stuck up too high when I used my Rhino Racks to carry my canoe.  The new shark fin style antenna is a nice design refinement and also stays low enough to stay below the roof rack.

 Interior

The most noticeable difference in the 2017 model is the interior.  Everything has changed  on the dashboard.

GM engineers wisely decided to remove the "sexy" center console with touch activated buttons and went with a more contemporary styled user interface with separate manual climate controls and a touchscreen above.  It was far too easy to accidentally bump one of those pretty touch buttons on the old white center console.

power outlet and 2 USB inputs for media
plus a 3.5 mm audio input jack

Some of the  the features I have come to enjoy already include the Wi-Fi hotspot, and voice command for the entertainment system.  For instance I can press a button on the screen to enable voice-recognition and then simply say: "play Adele 25" and it will begin playing the first song on the album.  I have plugged in a thumb drive with all of my favorite music to one of the two USB jacks in a small lighted cubby in front of the shifter.  There is a slot to the right of the shifter for a phone or music player, I leave my phone there whenever I'm driving both to charge it and for Android Auto navigation.  The Android system puts live Google maps on the center console screen.  It also allows hands free phone and texting by voice.

 

A major improvement is the re-positioning of the POWER and MODE buttons.  More than one driver has inadvertently turned off their vehicle while driving because they intended to change modes (normal, sport, mountain) but hit the POWER button accidentally in the Gen 1.  I had a terrifying experience at night doing just that at high speed on a two-lane blacktop.  Now the power button is logically located near where an ignition key would be in a conventional vehicle, while the MODE button is down near the shifter where it should be.

The shifter location and layout now make a lot more sense with the parking brake located at the left, hazard lights at lower left, and MODE and TRACTION control buttons at the bottom.  I never understood  the strange placement of these controls in the GEN 1 design.

The new armrest controls slope towards the driver, making them more accessible.  And the gas filler release button is now placed in a much more visible location.  In the Gen 1 it was hidden from view.

Above the mirror, the OnStar controls have been moved forward and simplified.  The large black button in the center of the GEN 1 image on the left was the traction control button.  A very odd place for it, and it makes perfect sense that they would move it down next to the shifter.

The new keyfob is slightly sexier and the same remote control features have been retained.  If you press the lock button briefly and then press and hold the power button for 3+ seconds, you can power up the vehicle for 10 minutes and it will utilize the last temperature setting of the climate control system to heat or cool the vehicle as needed.  The substantial difference in the GEN 2 model is that the heater is much more effective.  On recent days when temperatures dropped below 0°F, I was able to preheat the vehicle for 10 minutes and get into a comfortably warm car with a cabin temperature around 70°F.  The GEN 1 heating system was lame by comparison.

The rear seats now include a center seat with a fold-down armrest. rather than two separate seats.  It functions more like a bench seat with a 60/40 split fold-down.  While the center seat would not be comfortable for anyone other than a child, I'm sure it adds some value to those with children.

The rear cargo area is much the same, except for the gap between the seats which was convenient for loading 8 foot lengths of lumber for me.  Yes, you can fit 8 foot 2X4s inside the vehicle by sliding them all the way into the front passenger foot well.

With the rear seats folded down  one notices the absence of the window in the rear hatch reducing visibility even more.

Due to the reduced visibility, GM have wisely incorporated a rear camera in the base model.  Previously this option was only available as an upgrade, but without the rear window it is now essential.  And notice that it shows guidelines indicating where the vehicle will be as you backup - they interactively curve as you turn the steering wheel.  I'm sure that children, dogs, and toys will be much safer now.  The camera is located just above the rear license plate.  In rainy weather I make a point of wiping off the lens before getting in the vehicle as it gets covered in road grime.

The GEN 1 charge cord was originally stored under the rear hatch, but I never left it there because it was too inaccessible.  The new cord storage location is more readily accessible, but there is nothing to wrap the cord around, so it is a loose 20 foot cable which becomes awkward to handle in snow and bad weather.  I think I prefer the original charge cord, but in both vehicles I just leave the cord out in the rear rather than bothering to stow it.

Everything under the hood has changed completely.  The large orange high voltage wires to the electric motor are tucked inside somewhere, and I hear that the new four-cylinder gas generator engine is smaller and lighter.  But it's all black box stuff.  There be magic!

Overall I am thoroughly impressed.  It seems that GM were paying attention to all of the observations, pet peeves, and complaints about the original design.  They totally got it right this time!

Too bad they stopped making this amazing vehicle in March 2019.