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Sunday, January 7, 2018

Repairing the tankless propane boiler for my solar augmented heating system

4 solar collectors shown at right
When I moved to Maine in 2001 I converted the open barn on my property to a well insulated workshop.  I also designed and built a heating system that uses solar and propane to heat the radiant concrete slab on the ground floor and baseboard radiators on the 2nd floor office/lab spaces.

The system relies heavily on the Bosch Aquastar BS124 tankless propane boiler that has performed flawlessly since it was installed with only token maintenance.  (You can see a system diagram and live performance charts on my web site.)  Unfortunately it recently failed dramatically due to a prolonged period of extreme cold. 

In the images above you can see the storage tank that accumulates solar heated water during the sunny hours of the day.  Above left is the boiler that automatically brings the water temperature up to 140F when it is lower than that.  In the dead of winter I am lucky to get 140F in the tank so the propane boiler runs a lot.  To reduce the propane consumption, I use my wood stove.  The drawback to the wood stove is that when lit it pulls air into the building and that comes through the powered exhaust vent above the boiler.  Originally, the boiler vent had a flapper valve on the outside to prevent a back draft, but I had foolishly removed it.  So what happened this winter is we got a prolonged period of very low temperatures with night time temps dropping below zero a lot (see the red line below).
(lost data on Dec 28 for some reason)
So on December 30th when the wood stove was running and the heater was off - the cold back draft got down to -15F and eventually a pipe burst in the top of the heat exchanger:
Heater running AFTER repair - arrow shows location of the burst pipe
The arrow points to the section of pipe that blew open.  I immediately researched replacement parts and found a source for a complete replacement copper heat exchanger and in a panic - ordered one online for $350.  But then after calming down, I realized that the damage really wasn't that bad, and that I probably had the plumbing skills to repair it since I had plumbed the whole system myself!
Here is what the burst pipe looked like when I looked closely at it.  It was fairly simple for me to gently hammer the lips of the burst out section back together after draining the system down below the leak.  Then I carefully sanded the whole area around the cut to expose clean copper.  I wiped on a lot of paste flux and warmed it all up with a blow torch.  By gently applying solder, I was able to fill the crack and build a layer of solder over the whole area.  Problem solved and I canceled my order for a new heat exchanger!
There is no running water in the building so in order to re-fill and pressurise the system I had to drag a garden hose across the yard from the house.  This was challenging with 8" of snow on the ground and day time temperature peaking at 10F!  I had to pre-warm the 2 - 50ft lengths of hose in front of the wood stove to loosen them up first!  But it all worked out and it has been holding 50psi pressure for over a week now.  And of-course I made a new back draft flapper for the vent to prevent frigid air from being drawn in again.

Problem solved!  And I saved $350 in replacement parts!  Incidentally the whole building only uses about $200 gallons of propane a year at a cost of about $400 in a good year.  This is very inexpensive and due to the great insulation, interior storm windows and about 1 cord of firewood that I cut for free on my property.


Wednesday, September 13, 2017

Simple fix for a defective solar light


 Last June (2016) I wrote about these great solar yard lights with built in motion sensors.
 
I have them deployed all around my home and it is delightful to walk around and see them turn on from up to 20 feet away to light my way.  Each successive generation of these lights seems to have more LEDs and are brighter.

I recently ordered a 4 more from a different manufacturer and 1 of them did not work.  I had read in Amazon reviews that this had been an occasional problem.  Some manufacturers are friendly about replacing defective products, and some are not.  I decided to take matters into my own hands ad see what the issue was.  It was easy enough to remove the 4 screws from the back and here's what I found:


The battery clip had come out of its housing.  It was simple to slide it back in place and all was well!

I share this experience in the context of sustainability because many people would consider disposing the defective item in the trash since the expense of returning it would be more than the cost of the unit.  But these contain Lithium Polymer batteries that don't belong in the landfill.  So even if the electronics were defective, the battery should be recycled.  Lithium is a toxin that must be recycled safely and most hardware stores have a collection box for rechargeable batteries.  

It is important to note that these particular batteries are removable and replaceable, potentially extending the life of this product for many years!  The LEDs are typically rated for 50000 hours continuous use (about 5.7 YEARS!).  Since these are used only a minute or 2 a day, they should last indefinitely.  Same goes for solar panels that should last over 20 years.  These particular solar cells are embedded in plastic resin that eventually clouds over, but this does not seem to affect performance.

Monday, August 21, 2017

Partial solar eclipse and solar output



Maine photographer Mike Leonard drove to Illinois to capture the image above of the total eclipse today (August 21, 2017).  Here along the Maine coast we saw a partial (50-60%) eclipse.  It definitely got noticeably darker and cooler and impacted my solar power output.

The chart above came from my Weather Underground personal web page, there's a clear dip in solar Watts.

Looking at the past 5 days of the power output of my solar power system, you clearly see the correlation as the eclipse occurred today.

Zooming in it becomes even clearer.  Utilities that rely on large solar farms need to plan ahead for an eclipse by having their peaking generators on standby.  These are typically natural gas or hydro generators that are nimble enough to be able to ramp up their output rapidly.


I have a single 245W solar panel on the south wall of my house that also shows the power drop.



It was also interesting to feel the temperature drop.  The change was palpable when I was outside.

So that's how a solar energy geek experiences a solar eclipse!  The next full eclipse in the US will be on April 8, 2024 and we should get a nearly full eclipse in Maine.

Saturday, August 19, 2017

Maine blueberries and making jam

August in Maine is the time when my fruit trees and bushes produce a bounty.  I have 4 high bush blueberry bushes that are nearly 20 years old and well cared for.  I actively prune them in the spring and feed them coffee grounds and plenty of water in the summer.  This year I have been picking over a half gallon of berries almost daily.  Total crop will be well over 6 gallons I think.  They ripen so fast that I recruit friends and neighbors to come and help themselves.
I store them in the fridge and make small batches of 4-6 jars of jam every few nights.  So far I have made over 35 jars.  I am selling the jam to my airbnb guests and giving it to friends and neighbors.  It is really good!




My cherry tree produced a bumper crop this year, but I could only reach the proverbial "low hanging fruit" which was enough to give batches to 2 of my neighbors with baking skills.  They each made a great cherry pie!










The next crop will be from my large crabapple tree.  Last year I harvested over 7 gallons and made over 30 jars of crabapple butter and jelly.  This whole process is much more labor intensive and I'll have a friend help me.  First I spread a large tarp under the tree and then I shake the tree one branch at at a time using a long hooked stick.  We then sit on the tarp and sort the good fruit into 5 gallon buckets.  In the heat of the summer this can be really tiring.

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. 
It has been my personal experience that Mason bees don't like the cardboard tubes here in Maine and the houses I built by drilling holes in wood have been much more successful at attracting them. 

Three weeks after installing my first bee house in June I found 3 holes plugged up and a bee working on another:

And in early September 2017 one House has many holes filled in, and more being filled:

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:

https://insteading.com/blog/insect-hotel/

http://www.masonbeecentral.com/100-tubes-and-liners

http://www.foxleas.com/make-a-bee-hotel.asp

http://www.gardeners.com/how-to/instructions-mason-bee-house/8085.html

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 or plug in hybrid vehicles and 3 of us have electric vehicles (Chevy Volts and Bolt).

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.