Tuesday, July 25, 2017

Fix it - don't toss it

 I have had this handy dual power (solar/battery) Radio Shack calculator for decades.  Recently it started producing weird results - reminding me of my series of artworks that deliberately satirize our implicit trust in electronically represented numbers.  Here's an example of a recent one:
"Digital Numeric Relevator Mk XXXIV - Hexadecimal Blues"
My "Relevator" series all look like Sharper Image products from the Twilight Zone and they just show senseless numbers that dance, fade, or de-construct in interesting ways.

It is disconcerting when a calculator shows wrong results!  So I opened it up to see what I could learn/do.  All it took was a miniature Phillips screwdriver:
... and there in the corner was a replaceable watch battery!  
It turned out I happened to have a spare battery laying around and "Presto!" it worked fine and the display was even more readable than it had been.

Being a geek, I always test a calculator by entering 22 / 7 since pi is a good exercise for the electronics and I happen to have memorized the first 5 digits.  So it's working fine now.

The point of my sharing this simple repair story is that it is often much simpler than you think to repair something.  So I saved this little item from the landfill and expect it to last a few more decades.  This is the essence of living sustainably.

Previous posts in this series showed:

How I repaired a broken torchiere lamp base

How I repaired my microwave oven

How I repaired my trash can lid

These repairs were simple and easy to do repairs, requiring minimal tools and basic ingenuity.  You can often find detailed help for repairing just about anything on the web and YouTube.

Monday, July 3, 2017

Mason Bees and bee houses

bee house
As many readers may be aware, bee colony collapse is a serious concern and the honey bee population is declining rapidly.  While there is still debate about the cause, the result is the loss of important pollinators.  I recently learned that honey bees are not native to the US and that solitary mason bees are.  These small bees are the hidden gems that help to pollinate our gardens and fruit trees.  They are not aggressive and their sting is mild - more like a mosquito bite.
mason bee
I read up on how to encourage and support them and found that you can easily make or buy simple "bee houses".  The simplest house is made from any block of wood.  You drill a bunch of 5/16" diameter holes 5" to 6" deep and the bees will lay their eggs in these holes along with some pollen. The bees then seal the hole with mud (hence the name Mason Bee).  The eggs hatch into larva and then then dig their way out as mature bees in the spring.  Click the image below for more info.
bee larva and cocoons

I built several bee houses from scrap 4X4" lumber with a small roof made from asphalt roofing shingle.  The roof is needed to keep the rain off and away from the sealed chambers and should protrude about 2".  

The houses need to be securely mounted so they face southeast or due east to catch the morning sun, this helps the bees warm up and get going in the spring. A good location for the bee house is under an overhang and out of direct weather, but they can also be mounted to trees.  Bee houses should also be located close to a source of mud, so near open water or very damp ground is ideal.  Solitary bees have a relatively small range of only 100ft or so, so they also need to be near blooms.  They are very active pollinators for fruit trees and only a dozen are needed to pollinate a fruit tree, whereas the same tree might need over 100 honey bees to do the same job.

Commercial bee houses often use paper tubes that can also be replaced.  There are many designs, here is one example that uses bamboo tubes:
While bamboo may work, I have learned that a 5/16" diameter hole is the size that Mason bees prefer.  If the hole is too small, they cant use it.  Too big and they expend a lot more work to fill the walls with mud to get their preferred size.

Ready-made bee houses are affordable at around $20 and can often be found at garden centers and big box hardware stores or on-line.  I don't recommend commercial plastic bee houses, apparently bees don't like them.  Stick with basic wood houses.

You can also purchase cardboard tubes separately in bulk and make your own house.  Holes or tubes can be lined with parchment paper to make them re-usable. 
Three weeks after installing my first bee house in June I found 3 holes plugged up and a bee working on another:

This is a simple and inexpensive way to support bees.  I have several fruit trees that I value and hope to encourage and expand my local bee population.

Some useful links:

Also a search YouTube shows many videos about keeping Mason Bees.

Tuesday, June 20, 2017

Quakers in Maine host a solar farm

I am a Quaker and was raised in England where the religion began.  We are properly called: "The Religious Society of Friends in Search of the Truth", or just Friends.  I am active member of the Midcoast Friends Meeting in rural Damariscotta, Maine and we recently decided to host a solar farm on our property.

The story begins in 2015 when Pope Francis released his encyclical entitled "Laudato Si".  The remarkable document is a call to action on climate change in which His Holiness lays out the issues clearly and concisely.  He talks knowledgeably about the science (he has a degree in science), but more importantly he chastises the world for placing capitalism ahead of the well being of humanity and all life on earth.  As he said once: “God always forgives; human beings sometimes forgive; but when nature is mistreated, she never forgives.” It is well worth reading and religious communities - Catholic and otherwise - have responded all over the world by taking action.  Some have divested their investments from fossil fuels, other have installed solar panels on their church roofs, and many other actions are being taken.

Friends found his message deeply moving and several of us formed a discussion group in late 2015 to explore his message and called it the "Climate Justice Group".  We met monthly and after talking about the encyclical for a while, we felt called to take action.

3 175W solar panels installed on Meeting House roof in 2008
Over the years we had already taken many steps to "green" the building by installing 3 solar panels on the roof (back when they were very pricey).  They offset a portion of the buildings needs. We also replaced all the lights with CFLs, and more recently LEDs as they burn out.  We switched the heating oil to a blend of bio-fuel and installed interior storm windows in the winter.  Many Friends drive hybrid vehicles and 2 of us have electric vehicles (Chevy Volts).

We were aware of a solar farm that been installed nearby.  This consists of over 170 solar panels that produce up to 50kW.  9 co-op owners get to use that energy to offset their electric bill.  Each member purchases as many panels as they need to offset as much of their energy as they choose.  The co-op leases the land from a landowner with open property to spare.

After some discussion the Meeting approved the idea of hosting a solar farm on our property and approached ReVision Energy - the largest solar installer in Maine to let them know we had a site available.  ReVision staff were very enthusiastic and actively supported and promoted the solar farm.  By the winter of 2016 the farm was fully subscribed with 9 owners and we signed papers leasing the land at the bottom of our field.  The Meeting House will get over $600 per year for the lease.

On Thursday, June 22, 2017 I got approval to turn the whole solar farm on.  Here's a picture of me activating one of the 5 inverters:
The solar array was producing 44.6kW after it was all powered up!

Here is an article in the local paper about the farm in the local Lincoln County News.

A web page for the Midcoast Friends Community Solar Farm show performance metrics. 

Here are some images showing the ReVision Energy crew installing the equipment:
installing posts and racking

rails installed

sturdy steel post with aluminum brackets

half the panels installed

5 inverters and controls

completed Midcoast Friends Community Solar Farm

Utility connecting the farm to the grid
View from the Meeting House
A few Friends were dismayed by the impact of the sight lines as seen from the front porch of the building.  So we have planted 2 dozen shrubs and bushes along the back to form a screen so we won't see the less attractive back side of the solar array once they grow in.
planting miniature arbor vitae trees
Quakers have made this statement concerning our perspective:

"Our faith as Quakers is inseparable from our care for the health of our planet Earth. We see that our misuse of the Earth’s resources creates inequality, destroys community, affects health and well-being, leads to war and erodes our integrity. We are all responsible for stewardship of our natural world. We love this world as God’s gift to us all. Our hearts are crying for our beloved mother Earth, who is sick and in need of our care."

For the whole document, click below:
Living Sustainably and Sustaining Life on Earth – The Minute from the Plenary
February 20, 2016

Hopefully our small contribution in support of renewable energy will help slow the impact of climate change.

Thursday, June 8, 2017

Replacing a failed solar microinverter

A few weeks ago I checked the Enphase Enlighten web portal (see it here on my web site) that shows the real-time performance of my solar power system and noticed that the top-left solar panel was not producing power.  The numbers showing Watts per panel are updated every 10 minutes, and you can play back data from previous days/weeks etc.

So I contacted Enphase and they confirmed that the M190 microinverter had failed and authorized an RMA for a warranty replacement.  These products are warrantied for 15 years and this is the 2nd one I have replaced so far.  (Microinverters convert DC solar power to 240VAC that feeds power into the building).  I received the replacement unit a week later and asked my friend John if he could come over and help replace it, John is a retired builder and enjoys climbing around on buildings!  We borrowed my other neighbor's ladders and climbed up to the roof.

It was a relatively simple matter to replace.  First I turned off the main breaker for the array, then climbed up and covered the panel with cardboard to prevent it from generating power while disconnecting and re-connecting it.  We unbolted the panel and moved it over to access the microinverter underneath.

It was quick work to remove and replace the new one which came with detailed instructions for safely performing the procedure:

I shot a time-lapse video of the process:

Once it was installed, I had to press a button on the Envoy web interface box so it could "find" the new inverter.  

Then a quick call to Enphase so they could update the web page that shows the array performance in real time.
This was a quick an painless process, and I'm grateful for good friends/neighbors and a great warranty on the products.

For more information about the process of installing my solar array, click here to see the detailed blog.

Monday, June 5, 2017

Solving mysteries with my new IR vision "super power"

Something has been bothering me recently.  When I drive home at night in my Chevy Volt and pull into my drive, the motion sensing lights come on.  Since I was driving in EV mode, the 1.4L gas engine/generator was not running - so there should not be sufficient heat signature for the IR motion sensors to "see".  (PIR - Passive Infrared Motion sensors have a white lens that focuses IR wavelength emissions onto a sensor that is able to distinguish warm moving objects moving against a cooler background).

Now that I have a "Super Power" - I can see in infrared thanks to my new FLIR One IR camera that I keep in my pocket. 

I just plug it into my phone and voila I can take still, video and time-lapse IR images.  It's so small - about the size of a keyfob that I now carry it everywhere in its protective case.

So I decided to "see" what was hot.  First I took a picture of the Volt in the 55F ambient weather:

Then I used the remote to turn on the vehicle and pre-warm the cabin to 76F - a luxury that I have always enjoyed in the Volt!  So here it is warmed up 10 minutes later:
You can see a little heat on the hood and driver side window but nothing really hot. (The camera scales the color palette to the whole image, so minor differences are accentuated).

So I drove into town and back, a round trip of about 14 miles in light drizzle. And here is an image taken right after I parked:
The noticeable difference is the tires!  They are 15-20F warmer than ambient now.  If it had not been a cool wet day, they might have been much warmer.  This is enough of a heat signature to trigger a motion sensor.  Mystery solved!

Here's a closer look at the tire:
Parts of the tire read over 75F which is 20F warmer than ambient!  Also the disk brake rotors were up above 85F

It's cool having this amazing IR camera in my pocket (along with my Moto Droid).

Saturday, April 15, 2017

Improving refrigerator efficiency

I live alone, and my kitchen has a typical refrigerator designed for a full household.   I am not one of those people who needs to keep a lot of food in the refrigerator, so it sits largely empty most of the time. One of the drawbacks of a lot of empty space in a refrigerator is that it becomes inefficient.   Every time you open the door all of that cold air falls out.  If your refrigerator is filled, there is less air to fall out, but more importantly there is more thermal mass storing the cold inside.  My solution to an increase the efficiency of my refrigerator is to store gallons of water in old milk containers.  This is a simple, easy solution that seems to reduce the run time of my refrigerator.  If you have empty space in your refrigerator, I suggest you save some milk containers and rinse them out thoroughly and store water in them, it's always handy to have some cold water around anyway.

Tuesday, March 14, 2017

Trash Talk

I live in the small town of Woolwich, Maine with a population of around 3000 people.  Our town is managed by half a dozen selectmen and women, and we meet annually in the school gym to vote on the annual budget for the town.  In recent years our town has been hotly debating how to manage waste and recycling.  Since our town is equally divided between what can best be described as ignorant rednecks and liberal progressives, the debate can be quite lively.

The issue of how to encourage more recycling has been on the table for years.  Our recycle to waste ratio is about 25% recycled which is pathetic compared to most other local towns that recycle 50 to 60% of their waste.  A few years ago we voted to institute a Pay As You Throw program in which you had to buy bright orange labeled bags from the town in order to be able to put trash out at the curb for pickup.  The bags sold for $1 each and this so thoroughly pissed off one local that he petitioned for a special town vote to repeal this program because he felt it was punitive to those with low incomes.  His shortsighted thinking did not acknowledge that this program would save the town over $80,000 a year and thus reduce our property taxes.  However his petition passed due to a very vocal minority at the meeting and the program was canceled after three months.  The program was wildly successful during the three months that it operated and our recycling rate went from 25% to over 45%.  The moment the town stopped using the bags again recycling dropped back down to below 30%.  I am often embarrassed to be a resident of this town for reasons like this.

On the bright side, we do have mixed stream curbside recycling.  This means that we can dump anything recyclable into a bin and leave it at the curb.  It is picked up and sent to EcoMaine - a nonprofit facility that is co-owned by several local towns.  There they sort and separate the plastic, glass, paper, cardboard etc. into bundles that can be sold.  My personal ratio is about 60% recycling 40% trash by weight, and I believe my ratio is improving this year but I stopped weighing my trash bins at the end of 2016.

EcoMaine furnace
The good news is that we have now opted to send our trash to a Waste-to-Energy furnace that is also operated by EcoMaine.  The furnace produces steam to drive an electric generator.  The power produced is sold to offset some of EcoMaine operating costs.  The ash from the furnace is screened for metals and is then sent to a landfill owned by EcoMaine.  So ultimately the amount of waste that is landfilled from our town is very small.  The problem is that a lot of recyclable materials are being burned due to the laziness of our local rednecks.  

I remember touring a recycling sorting facility in Massachusetts many years ago and noticed that all of the glass no matter what color was crushed and dumped into a bin.  I asked the plant operators what happened to that glass.  They said that the aggregate color is a light brown and it is sent to a local Coors bottling plant where they reuse the glass to make beer bottles.  This is just one of the many ways in which recycling operates in a successful way regionally.

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.