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Saturday, December 19, 2015

Why I love paying my electric utility bill

I installed the first part of my solar power system in the fall of 2009 and immediately my power bills dropped considerably. 

The chart below shows the energy flows for my property over the last several years:
Take a moment to study this chart and look at how everything interacts.  The yellow line shows how much surplus energy I export back into the grid on a monthly basis from the solar array.  Clearly, in the summer I am exporting a lot more and this more than offsets my net energy for the month.  Whenever the green net energy line goes below zero, that is when I have a credit.

This chart shows my actual bottom line monthly electric bill:
Over the years I have scaled up my solar power system and now my electric bills flatline in the summer, bottoming out to the minimum connection fee.  This year I had a surplus  from May through October and the utility gave me a credit that carried forward until it was used up.  This electric bill covers both my house, workshop, and the electricity used to charge my Chevy Volt.  So, not only am I not paying for utility energy for months at a time, I am also driving up to 37 miles a day for free on solar power.

During the summer months the energy I am exporting into the grid reduces the load on the power lines feeding my immediate neighborhood.  As neighborhoods grow, the utility often needs to upgrade the infrastructure in order to deliver power to outlying areas.  If new housing developments were all to incorporate solar roofs on their houses, this would reduce the cost of deploying and maintaining power lines to those areas.  You would think that utility companies would appreciate this benefit, but in reality they are pushing back against it because of the lost revenue.  Some utilities are even trying to punish customers with solar power with a surcharge to cover maintenance costs on their power lines.  

My solar power system, like most systems installed in the last 5 to 6 years is utility inter-tied.  This means that there is no battery bank and surplus energy is returned to the grid rather than being stored in batteries.  However, battery technology is now reaching the point where it is beginning to become relatively affordable to pull the plug on the utility altogether and simply store that surplus energy in a battery for use overnight and on cloudy days etc.  This is referred to as "grid defection".  Renewable energy pundits are suggesting that entire communities could pull the plug in the future and that utility companies will need to figure out a new business model.

Friday, December 4, 2015

Safely disposing old paint


Paint cans accumulating in my utility room
Do you have a place in your home where old partly used paint cans have accumulated?  Have you thought about how to dispose of those cans of paint safely?  Until recently there were very few options that are environmentally benign.  You can leave an opened can of latex paint out in the open until it dries out completely and then safely dispose it in the trash.  For smaller amounts of water-based paint left in the bottom of a can you can wash out the can in the sink and then put the cleaned empty can in the trash or if it is really clean - in the recycling bin.  This is not recommended for septic tanks however.  And finally, for solvent paints the only responsible option is to take them to a hazardous waste disposal facility which is tedious.

http://www.paintcare.org/ 
There is now a new option offered through a nonprofit industry trade association called PaintCare that is setting up return/recycling centers where old paint can be turned in and recycled or disposed of properly.  This paint can now be collected for reuse, recycling, energy recovery, or safe disposal.  As of this writing, in December 2015 there are only eight states offering this service and you can use a map on their website to find a drop-off location near you.  These are typically hardware or paint stores or hazardous waste disposal sites.

According to their website: "The program is funded through fees on each container of architectural paint sold in states with paint stewardship programs. Budgets and fees are set on a state-by-state basis. So far these fees have been the same in each state with a program: 35 cents, 75 cents or $1.60 per container, depending on the container size."

I was very pleased to learn about this program and will be going through my collection of paint going back 15 years to decide what to recycle.


UPDATE - a few days later
drying out old paint residue
I just returned from the hardware store that participates in the program.  I took five  gallon cans with varying amounts of paint in them and the first thing the guy did in the paint department was to turn the lighter weight cans over and tap them on the bottom.  From this he was able to determine that there was a thin layer of congealed paint in the bottom that he could not use.  He told me that they are recycling the paint as useful paint and not as dried out material and that I should leave the cans open outside until the paint dries out and then just dispose of them in the trash.  Any can that is one third or more filled with liquid paint is useful to them.  

I asked him how often the paint was picked up and he said they cart off 250 gallons a WEEK!  This is just from one local Ace Hardware store in Maine.  Wow, talk about a successful program!

Saturday, November 14, 2015

From tree trunks to bowls

A few years ago my friend Tom asked me if I would clear some trees from the field below his house.  I was delighted to discover that there were several cherry trees with trunks ranging from 6 to 8 inches in diameter.  Since I enjoy wood turning, I brought some of the logs back and made bowls from them on my lathe.  Turning fresh, green wood is very enjoyable because it is so soft and cuts easily.  Then, as the finished bowl dries it changes shape and curves up into a boat shape which adds a lot of charm to a handmade bowl.  

some of the bowls I made this year
The bowl on the right is cherry and the three small ones are made from a small plum tree that died on my property last winter.  The large salad bowl came from a piece of maple that my friend Topher gave me from a tree that he had felled on his property this spring.  It is beautiful spalted maple, and took me hours to turn because that wood is so very hard.  


Below is a picture of that bowl, along with the other half of the log that it came from.

I have sold a number of these bowls at a local craft gallery and branded them as "Green Nut Bowls".  This is a play on words since these are typically used as nut bowls and they are made by me, a "green nut" - because they were made entirely using solar power.  I harvested the trees using my cordless and corded electric chain saws that derive their power from my solar power system.  And since my home and workshop are solar powered my lathe is also powered by renewable energy.
turning a small bowl (chainsaws in the background)
My lathe is a "hot rodded" 1950s Rockwell that I have heavily modified to use as a bowl lathe.  I removed the original motor and dropped in a 1HP electronically speed controlled motor that I can also reverse as needed for sanding and finishing.

Recently, some of my Bed & Breakfast guests have seen the bowls and asked me to make one for them and I was able to make one right in front of them since a small bowl only takes 30 to 40 minutes to turn.  I charge $7.00 per inch diameter, so a 5" bowl goes for $35.00.  I use the bowls I have made daily and the people that I have made them for tell me that they cherish them.  

From a sustainability perspective, I feel that I am making optimal use of a local resource in much the same way as Native Americans would have.  In the process of making each bowl, I consciously honor the life of the tree and give thanks for the gift of its wood.

Saturday, October 31, 2015

Shopping at my local Farmers Market

Bath Farmer's Market on the riverfront
Now that I am renting out my guest room as a Bed and Breakfast (via airbnb), I have decided to feature local foods for breakfast.  So I go to the local farmers market in Bath every Saturday morning which is on the riverfront about 5 miles from my home.  It is late October here in Maine and today is the last day that it will be held outdoors and it was quite brisk with temperatures in the low 40s.  For the winter the market moves into a large boat shed further up the riverfront.

I offer my B&B guests a breakfast that includes eggs from free range chickens, locally made turkey or pork breakfast sausage and/or locally made bread with my homemade Crabapple jam or jelly.  I also offer them dinner if they wish and I prepare anything from burgers made from local grass fed beef to salmon cakes served with locally grown vegetables.  I often find home made pies or muffins to offer for dessert.  Blueberry pie is a local favorite.
Goranson Farm stand
It is always a pleasant experience to review all of the offerings at the market and bump into friends and neighbors who are also shopping.  Some of the local farmers are better known to me than others.  I have visited the Goranson family farm several times and have watched them processing maple syrup in the spring.  They are one of the biggest organic farmers in the region with a large variety of produce.  I am always pleased to be able to support my local farmers and my guests compliment me on the food I prepare for them.

Community Supported Agriculture is a growing and thriving industry here in Maine.  There is a Farm to School program that has become quite successful at bringing fresh foods into the schools.  It is encouraging to see this focus on natural and organic foods and the public response to it.  While natural food can be more expensive, I firmly believe in voting with my dollar for a more sustainable future for our planet while also the supporting local economy.

Sunday, October 25, 2015

Renewable energy Net Metering billing explained

I installed the first phase of my solar power system back in the summer of 2009 with the help of many friends and neighbors.  Once the system was commissioned and approved by my utility, I signed a Net Metering Agreement with them.  This contractual agreement stipulates that they give me full retail credit for every kilowatt hour of energy that I export from my property back into the grid.  Originally, I had a traditional old-style analog meter and this meter would simply turn backwards on a sunny day before they came out and installed a second meter as part of the Agreement.  From this point forward my bill indicates readings from both meters.  One meter indicates how much energy I have imported from the grid, and the other indicates how much energy I exported.  I am billed (or credited) for the NET difference.
My electric meters
In the image above, the top meter shows that I have imported 22476 kWh and exported 11017 kWh since these meters were installed in April 2011.  Essentially I have offset 50% of my energy over six years using solar power.  Since the system has grown over time that percentage is currently higher.  For instance, over the last 12 months I exported 3383 kWh, imported 5222 kWh with a net usage of only 1983 kWh

In the summer months I export more than I import and thanks to the Net Metering Agreement, the utility gives me a full retail credit for every kilowatt hour exported and this credit is carried forward.  They do not pay me directly but simply apply this credit to subsequent bills until such time as I use it up.  They do not carry a credit forward if it has run over 12 months.  I have had a very good year this year and have not paid my utility for electricity since May (it is now mid-October) and I am still carrying a credit that will apply to my next electric bill.  Here is the section of my bill indicating the most recent meter readings:
Section of my electric bill showing imported and exported energy.
Not long after commissioning my system, I installed a TED 5000 real-time energy monitor in my circuit breaker box.  This feeds information to a web page that I can view on my local network.  This helpful tool allows me to view energy consumption in great detail in various charts showing energy consumption by the second/hour/day/month.  Below is a screenshot showing monthly energy flow for the last couple of years:

Chart updated in July 2016
 Blue indicates energy imported yellow  indicates solar energy produced and  green  indicates the net energy per month.  I had a net energy surplus for 3 months each summer.


In a larger context, I am considered a micro generator that contributes power to the grid.  By doing this, I am reducing the load on the local grid which actually does the utility a favor.  However, the utilities do not see it this way due to the lost revenue and many utilities are beginning to fight back to prevent them having to give credit or payouts to people that provide renewable energy into the grid.  This is shortsighted thinking and they are going to have to adjust their business model as more renewable energy systems are brought online.

Thursday, October 22, 2015

Energy efficient motion sensing night lights

I am revisiting the topic of night lights.  Last month I wrote about "Low Cost to Operate Night Lights" and discussed electroluminescent and LED nightlights that provide a sufficient glow for navigating a dark home at night.  These lights stay on 24/7 and thus they are on in the daytime when they are not really needed, however since they only cost around $.02-$.10 per year to operate this is of little concern.
Motion sensing night light
Recently I decided to try out some motion sensing LED night lights that only illuminate when motion is detected in a darkened room.  These well-designed units are available in packs of two for about $20, and come in cool white and warm white options.  I placed one in my front hallway and another in the bathroom and have found that I now no longer need to turn on the lights when going to the bathroom at night or when coming into the house after dark since they provide sufficient illumination to see.  This is significantly more light than the always-on LED lights I reviewed recently.  It is quite pleasant to have a light come on automatically just when and where you need it.  They have an impressive range and turn on instantly when they detect someone moving around at night and remain on for 60 seconds.  If you stand or sit perfectly still, they will go off which can be sometimes disconcerting in the bathroom, but the moment you move again they come back on.  For this reason I wish there was a switch to enable them to stay on longer.


Motion sensing night light only activates in the dark

As an engineer I naturally needed to quantify how much energy these lights use compared to the LED lights I wrote about recently.   I found that they consume about 3 Watts in both the off and on state - about half the power of an old-style night light lamp.  I was actually a little surprised to find that the unit uses slightly less power when the light comes on!   Clearly the motion sensor is using power all the time to  detect motion and ambient light.  This means that their cost to operate if you are paying $.10 per kilowatt hour for electricity (which is the US national average) is around $.21 per month or $2.60 per year.  While this is more than the $.10/year cost to operate an always-on LED nightlight I find the trade-off quite amenable.

The sensor is a Passive Infrared Sensor (PIR) that works by detecting infrared light emitted by warm bodies.   The lens in the dome of these sensors focuses IR light onto a device that triggers when it sees warm objects passing across its field-of-view.  There is also a photocell that detects ambient light level and disables the light when the ambient light is above a certain threshold.

I am so pleased with these lights that I plan to order a couple more.  While they do use more energy than other types, I have enough surplus power from my solar array that I can spare a few Watts.  I have not paid for grid power since May (just payed my Sept-Oct bill and still have a credit on my account thanks to net metering).

Saturday, October 17, 2015

Charging up my solar heating system

South end of my workshop showing 4 solar collectors
It is mid October and we have had our first few frosts here in Maine and they had a few inches of snow in western Maine yesterday.  This means that it is time for me to fill the solar collectors on my workshop heating system with antifreeze.  The heating season lasts until mid-May here and in the winter temperatures rarely get above freezing for up to three months.  My workshop building is super insulated and I heat it with a combination of solar, propane and a wood stove.  I use a cord of wood that I cut and split myself from my backwoods to heat the downstairs area, keeping it around 60°F and higher if I am actively working in the space.  I use the solar/propane primarily to heat my second-floor office where I am more sedentary and set the temperature around 70°F or so during my working hours.


Pumping a bucket full of antifreeze into the collectors
To fill the collectors, it takes around 6 gallons of 50% Dow Frost antifreeze.  I use a small electric pump and hoses to pump this fluid into the system and pressurize it to 10 psi.  It takes a while to eliminate all the air bubbles from the system so I leave the pump circulating for a while to push the bubbles out of the plumbing and collectors.
DTC-D Solar Differential Temperature Controller
Once the system is filled, I connect the 3 small solar panels on the roof to the Differential Temperature Controller that I designed and manufacture (shown above).  This device monitors the temperature of the collectors and the storage tank and only activates DC circulation pumps when the collector is hotter than the storage tank by at least 10°F.  Powering the circulation pumps directly from solar panels guarantees an efficient and reliable heating system.

You can see live performance charts and gauges of my heating system on this page of my website.  On a good sunny day in the winter the system can raise the 80 gallon storage tank temperature by over 40°F.  The stored heat is then fed to baseboard radiators at night as needed.  If the stored water temperature drops below 140°F a Bosch Aquastar boiler automatically makes up the difference to ensure that heating water is always delivered to the radiators at 140°F.

Tuesday, September 29, 2015

Unsustainable tech product packaging


Linx evaluation kit - case not to scale
For the last 40 years or so I have been designing and developing electronic products.  Many of these products incorporate short range radio controls, and this has become a specialty of mine.  For the last 20 years or so I have been working with a company called Linx Technologies that make a broad line of miniature radio chips and antennas that are ideal for small products.  When they introduce a new product I sometimes order an evaluation kit from them that typically costs around $100.  These kits include battery-powered demonstration circuits that help to familiarize you with how they work.  

Linx have just released an exciting new radio product that I plan to use in a project I am currently developing so I ordered the relevant evaluation kit (see their promotional image above).  In the past, these kits were shipped in small custom fitted cardboard containers and it was quite simple to recycle the cardboard materials.  Not so with this newest kit that came in an aluminum case that weighs almost 3 pounds and measures 14" x 10" x 4".  I was stunned when the package arrived because it was so huge and heavy.  The distributor (Digi-Key Corp.) packed it in sustainably sourced paper packing material that can be recycled, but I have no idea what I am supposed to do with this large metal case.  I do not need to clutter my home office with this albatross, and will simply store the components on a shelf.  Here are is a picture of the relatively tiny (and not very fragile) parts inside the case:
Kit with all parts visible
I find the idea of shipping small items weighing only a few ounces in a 3 pound case to be completely offensive to my sensibilities as someone committed to living sustainably.  From my perspective this is a 1950s style Mad Men style promotional concept that has no place in today's world and it made me angry.  I also have to question the 1 pound stack of documentation that came in the kit.  While it is convenient to have paper manuals, technology companies do not commonly send any paper documentation with their samples since everything an engineer needs to know about their products is available from their website.  15+ years ago I used to have bookshelves filled with thick technical manuals, but they have all disappeared in favor of PDF documents readily available on corporate websites.

My small rural town recently switched to a Pay As You Throw (PAYT) program which requires our trash to be placed in specially purchased orange trash bags that cost $1 for a small bag and $2 for a large bag.  The purpose of this program is to incentivize increased recycling in our town and I am hoping it will have the desired effect.  Currently the town recycles around 20% of its waste stream, while I am averaging 60%.  The impact of the new program on me is that I resent companies that send me products packaged in bulky non-recyclable materials.  I have conveyed my displeasure to the sales person I work with, and he says he will talk to the marketing department at his company about my concern.

There are so many companies that are embracing social responsibility on so many levels that it makes me sad to see a good company that ignores the realities of a planet with finite resources.

After seeing this blog post, the Linx salesman that I work with offered to pay for return shipping of the offending metal case via FedEx.  I appreciate his thoughtful response to my displeasure.

A friend saw my blog and has asked if he can have the case.  Giving it to him has a lower carbon footprint than shipping it back across the country.  Everybody wins!

Friday, September 25, 2015

Sustainably sourced dining room chairs

My wife and I have separated after 20 good years and she has moved back to California where we first met.  It is an amicable separation but nonetheless she ended up taking a lot of furniture and other essentials with her.  This left me without a set of dining chairs.  Ideally I wanted chairs that were sustainably sourced in some way.  My original thought was to approach my friend and neighbor, John who is a skilled furniture maker because he had recently made a really stunning set of craftsman style chairs for his home.  But he explained that it would take up to a week per chair to make them even if I was helping and I realized I had neither the time or the money to invest.

My next step was to go to a local furniture store that represents Amish furniture makers.  They had a variety of samples that I found quite suitable for my needs at prices ranging from $230-$265 per chair and this was the upper limit for my budget.  The problem was that it would take 6 to 8 weeks to have the chairs made.  At this point it occurred to me that I really do not need heirloom quality furniture since I have no children or heirs who may wish to inherit furniture from me.  Also I did not want to wait that long because I had decided to convert the guest room in my house to a B&B using airbnb and wanted to get that set up pretty quickly.  Click here to see my listing, I have already had a few guests and I am getting reservations for the fall color season here in Maine which peaks in mid October. (We refer to the out-of-state visitors who come for the fall as "leaf peepers"). 

So finally I resorted to searching for chairs on the web and found a nice set of chairs from Sears.com on sale for under $50 each.  While I was not particularly comfortable with the idea of chairs that are made in Malasia, I did learn that they were made from "sustainable rubber wood".  In doing my research I learned that rubber wood has come into usage in the last few decades as a secondary use for trees from rubber plantations.  When these trees reach the age of around 30 years, their production diminishes and they  are harvested for their wood and the plantation is replanted.  The wood itself is prone to infestations from beetles, but when treated properly and dried correctly it can look somewhat like mahogany.  It is an attractive hardwood that takes stain and finish very nicely.

The chairs arrived at the local Sears store in a few days partially assembled in flat boxes.  Assembly was surprisingly simple and easy and I was impressed with the quality of the finish and the engineering of the joinery that makes for a very sturdy chair.
Chair parts
First chair assembled

The chairs did not take long to assemble, and look good with my family heirloom Jacobean reproduction oak table from England.
Whenever I need to purchase anything, I recognize that I am voting with my dollars for - or against - a sustainable future for humanity.  I take every decision quite seriously, particularly when dealing with large items.  But this also scales down to purchasing food at the local grocery store, natural food stores, and farmers market.  I make every effort to support local agriculture or acquire foods that are not shipped in from another country.

Thursday, September 10, 2015

Low cost to operate night lights

Here in rural Maine there are no streetlights or reflected city light at night so it gets DARK at night.  This means that when the lights are out inside the house it can be difficult to navigate to the bathroom or kitchen.  So for this reason I have liberally sprinkled nightlights throughout the house to make it easy to get around without having to turn on  lights.  
7 W night light
The classic old-style standard 7 W light bulb style nightlight has been obsolete for several years and I personally have never used them but I did the math and calculated that if you are paying $.10 per kilowatt hour (which is about average) for electricity, each one of those old light lights would cost over six dollars a year to operate which is more than many of them cost to purchase new off-the-shelf!  if you happen to have one of these dinosaurs in your home, I encourage you to discard it immediately and upgrade to the newer technologies.

In the past I have purchased three packs of electroluminescent nightlights for around $10-$12 and they tend to last several years before they eventually grow dim and become relatively useless.  I tested one of these lights and found that it draws .033 W for an estimated cost of about 2.5 cents/year.  A few days ago I was in the hardware store and saw a two pack of blue LED nightlights selling for under nine dollars and thought I would try them out.  LEDs draw a little more power at .125 W for an operating cost of around $.10/year.  LEDs are typically rated to last 30,000 to 50,000 hours so I expect these to last 3 to 5 years.

Here are some comparison images of LED (top) and electroluminescent (bottom)  with ambient lighting and lights out:
LED vs electroluminescent night light in ambient light

LED vs electroluminescent night light in the dark
The LED is significantly brighter and cast a visible pool of light in a dark hallway, while electroluminescent ones are just enough to see by, similar to moonlight coming through a window.

There are other types of night lights that contain light sensors and motion sensors so they turn off when they are not needed.  I suspect that those that use a motion sensor consume a fair amount of power even when they are off just to maintain the motion sensor.  (they do, see this blog post).  I leave mine on all the time since their cost to operate is so trivial.