Sunday, December 18, 2016

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:

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.

Friday, December 16, 2016

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.

Tuesday, December 13, 2016

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.

Wednesday, December 7, 2016

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.


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.


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.