Wednesday, April 5, 2017


One of our criteria for our house design was to plan for solar panels.  That meant having an unobstructed south facing section of roof.  With an attached hangar, there is no shortage of roof.  It also helps that the south facing roof is in the back, so the neighbors are less likely to be bothered.

Although we always planned to install solar at some point, the "when" was not clear.  For one thing, our finances were a bit stretched when we moved in.  The price of solar panels is dropping steadily, which argued in favor of waiting.  When we moved in, Michigan's rules for net metering were unclear with proposals to replace or change net metering under debate in the legislature.  This spring, a few things fell into place.  The legislature passed new legislation that clarified the rules - somewhat.  Projects completed in the next year are expected to be grandfathered under the current net metering rules for ten years.  Although it is still unclear what the rules will be for future projects, it is pretty certain they will be less favorable.  A little research revealed that solar projects could be financed under a program called Michigan Saves.  We decided to pull the trigger.

Our solar array includes 28 SUNIVA panels.  Each is rated at 280 watts, for a total of 7.84 kW.  The system was installed by Homeland Solar.  The installer sized the system based on our electric bills since we moved in last September.  We reduced the size a bit from their estimate because we really do expect to do better on electric usage in the future.  For aesthetic reasons, we decided to go with the all black panels even though they produce slightly less power per panel than the silver panels.

The first step was to set up scaffolding to safely get up on the roof.  Then, the support rails are attached to the roof.

After the rails are in place, panels are installed.

All 28 panels in place.
DC wires run from the panels on the hangar roof, through the hangar attic and the hangar, into the basement.  The Solar Edge 7.6 kW inverter is installed in the utility room.  Although the inverter is a few feet away from the electrical panel, the AC wiring cannot take the direct route.  The utility requires an exterior shut-off switch near the electric meter.  In most homes, the electric meter is close to the electrical panel, but not in ours.  Fortunately, in anticipation of eventually installing a generator, we had the foresight to install a conduit from the utility room to the end of the house with the meter.  The installers were able to pull three sets of wires through the conduit: one from the inverter to the shutoff switch, one from the shutoff switch to the electrical panel, and one for the eventual natural gas standby generator.

In addition to the electric meter (left) and the gas meter (middle), we now have a solar disconnect switch on the end of the house.
The installed cost came out to $2.55 per watt ($1.79 after the 30% tax credit).  Our monthly payments under the Michigan Saves loan will be a little bit more than the expected reduction in our electric bill, so the project is not quite cash flow positive in the first year.  If electric prices go up, we will be ahead.  In ten years, the loan will be paid off, so we will be saving money even if the net metering terms are not as favorable.

Saturday, March 25, 2017

Central Vacuum

While our house was under construction, our vacuum cleaner gave up in the midst of cleaning the apartment.  It never did a great job.  Suddenly, it just made a lot of noise and unpleasant smells.  Tired of buying vacuum cleaners that don’t work well and break in a couple years, I went about researching higher quality vacuums.  Having learned a little about indoor air quality, I also wanted one that wouldn’t spew particulates into the room.

I concluded that the best solution would be a central vacuum.  The price tag is many times that of the ones we usually buy at the local store.  There are some high-end portable units that claim to be a big improvement, but the price tag on those is in the same ballpark as a central vacuum.  The manufacturers of both the high end portable units and the central vacuums advertised that their products would do a superior job of cleaning and would last many years.  I found those claims easier to believe for a central vacuum.  One feature that no portable unit could match is exhausting the fine dirt out of the house with no possibility of spewing it back into the indoor air.  Even after I was convinced that a central vacuum would be superior, it took awhile to get comfortable with the idea of spending that much on a vacuum.  Our house was at the ideal stage of construction for installing a central vacuum.  The house was framed but no drywall was installed.  Since that wouldn’t be true for much longer, we decided to pull the trigger.

One feature that we debated was the hide-a-hose system.  With this system, hoses are stored in the tubes so you don’t have to carry a bulky hose from a closet to the room you want to vacuum.  We decided that not having to carry the hose around and coil it back up afterwards didn’t justify the extra cost.

One undeniable drawback of the central vacuum is that it was absolutely useless for cleaning the apartment in the meantime.  Fortunately, my parents had an extra unit sitting around.  Apparently, some people buy new vacuums before the old one fills the home with smoke.

After living with it for a few months, we are happy with the choice.  Mainly, we are thrilled that it does a very good job picking up the pet hair and other stuff from our floors.  Convenience is pretty much a wash compared to a portable.  You still need to get something out of a closet, carry it to the dirty room, and plug it in (although you plug in a hose instead of a cord).

This is the central unit, which is installed in the basement.

This shows the tube to one of the wall ports before drywall installation.
Here is what the wall ports look like after the walls are finished.
Under the laundry room sink, we have a Vroom unit.  This has a relatively short hose coiled up in the unit which can be pulled out quickly for little messes without getting the hose out of the closet.  When we decided to put this unit in the laundry room, we planned to have the cat litter in that room.  We ended up putting the litter box elsewhere and we don't use this unit as often as we anticipated.
In the kitchen, we have a dustpan unit.  When we sweep, the pile of dust is sucked into the central vacuum system.  We have discovered that we rarely sweep with a broom anymore.  Vacuuming is easier.

Sunday, January 1, 2017

Home Automation

Enthusiast of “the internet of things” imagine a world in which all or our devices seamlessly communicate with one another, anticipating our wants and needs, and satisfying them with little need for direct commands from us.  The reality is not quite there yet.

I didn’t set out to make our house a “smart home” filled with a bunch of devices communicating with each other.  One device at a time, I find myself sliding in that direction.  Some of my devices communicate with one another, although often not so seamlessly.  Sometimes they do what I want without an explicit command.  I am enjoying playing with the technology.  However, I couldn’t point to enough convenience to justify the effort and expense if I wasn’t enjoying the process.

Let there be controllable light

My first step into home automation came when I was tasked with procuring light bulbs for all of the light fixtures in the house.  I knew we wanted LEDs in most fixtures.  Like most other seemingly simple choices, I decided to complicate it by reading about the differences between various light bulbs.  It turns out that LEDs are not only available in different intensities, but also in different light temperatures.  Some light temperatures provide more soothing ambient light while others are more suitable for task lighting.  Then I read about Hue light bulbs.  These come in three types: white lights that have adjustable brightness, white ambiance lights that have adjustable brightness and temperature, and color lights that have adjustable brightness, temperature, and even color.  I bought these for many of the fixtures.  I also bought the Hue Hub.  The hub communicates with the bulbs through a radio protocol called Zigbee.  The hub also communicates with cell phones via wifi or the Internet.

This is a Hue Dimmer Switch.
It comes with a wall plate that makes it more or less
blend in with Decora wall switches.
However, we prefer just setting it on a countertop.
The On button cycles through pre-defined scenes.
The middle buttons brighten or dim the lights.
The Off button, not surprisingly, turns the lights off.
One feature I like is using the lamp on the night stand to wake me up.  The lights come on, at a low intensity, at a programmed time.  Then, they gradually increase in intensity.  I find it a much more pleasant way to wake up than a buzzing alarm clock.

After setting this all up, we discovered that the lights go back to a default each time they are turned off and then on again at the wall switch.  If the default was not what we wanted, we had to get a phone out and adjust it via the Hue app.  Nobody wants to go through that each time they want to turn a light on.  In order to take advantage of the Hue features, you need to leave the wall switch on and control the lights via Hue.  For some areas of the house, we invested in switches from Hue.  For other areas of the house, we ended up just not taking advantage of the light bulb features.  The light bulbs are grouped into rooms and each switch is associated with a room.  For each room, there are a few predefined scenes with different light temperatures and intensities, such as “Relax”, “Read”, and “Concentrate.”  Defining additional scenes is straight forward.  When you push the On button of the Hue switch, it comes on at the last selected scene.  Pressing the On button additional times cycles through other scenes.

This is a Hue Tap Switch.
It costs twice as much as the Hue Dimmer Switch
and is actually less capable.  Pressing the single
dot turns the lights off.  Pressing any of the three
buttons selects a scene.
My wife ordered an Amazon Echo for the family room/kitchen area.  Her motivation was the ability to stream music.  I discovered that, with a little setup, the Echo provides an alternate way to control the lights.  For example, if I say “Alexa, turn kitchen lights off,” the lights turn off.

The universe of possibilities

Many devices are now designed to be controlled via the internet using a cell phone app.  However, the cell phone app that is specific to the device isn’t the only one that can control it.  A web service called IFTTT (IF This Then That) allows you to control devices based on information from other devices and from outside services.  IFTTT has partnered with many manufacturers so that devices can accept commands to do things from the IFTTT service and can send signals to the IFTTT service to trigger actions.  This allows you to have one device trigger another device to do something.  For example, your garage door being opened can trigger your thermostat to go from away mode to home mode.  There are also a bunch of potential triggers from sources other than your devices, such as The Weather Channel and ESPN.  The possibilities are vast.  The useful possibilities are much less vast.  My first experiment with IFTTT was to make some of my Hue light bulbs turn to red whenever a Detroit Red Wings game started.  I made it work.  After it happened a few times, I turned it off because it was annoying.

In search of utility

I decided I was approaching this wrong.  Instead of going through the millions of ways I could automate things looking for something that would be useful, maybe I should start with something I actually wanted to automate.  I wanted the porch lights to come on near sunset and go off near sunrise.  If our porch lights took Hue bulbs, that would be pretty straight forward to accomplish.  But they don’t take bulbs, they have the LEDs built into the fixture.  They are controlled by three-way wall switches, one near the front door and one near the door to the garage.

This is our Wink Relay.  The little screen lets you do the things you would
normally do through the Wink App without getting out your phone.
It is installed in place of a single or double wall switch.
At least one of the two buttons controls whatever was previously
controlled by the wall switch.  It is also capable of doing some of what
a Wink Hub does, although that is pretty limited.
As I said at the beginning of this post, I didn’t set out to create a “smart home.”  By this time, however, I was interested in this home automation stuff.  I found some replacement switches with built in timers that would probably have been the simplest solution.  That is not what I did.  Unable to find replacement switches that interact directly with IFTTT, I decided to obtain a home automation hub and switches that would communicate with the hub.  The fact that the existing switches were 3-way switches limited my choices.  I decided to go with switches from GE that support 3-way switches.  For a home automation hub, I decided to go with a Wink Relay.  The Wink system supports two different radio protocols that are common for home automation: Zigbee and Z-wave.  The GE switches are available for either protocol.  Since I already had a bunch of Zigbee devices, I selected the Zigbee version.  The Wink Relay replaces one or two wall switches.  There are a number of limitations, though.  It cannot go where you have a gang of three switches.  It also cannot replace any 3-way switches.  The best place I could find was the switch in the master bedroom controlling the light on the balcony.  I installed the Relay and the GE switches and tried to get everything to communicate.

It turns out I had a few misconceptions.  The Wink Relay could not do what I wanted.  I needed a Wink Hub.  Wink had recently released a new hub product, so I ordered one of those.  Next, I learned that, although Wink supports both the Zigbee and Z-wave protocols, it only supports the Z-wave version of the GE switches.  So I ordered one of those and replaced the Zigbee version.

Now, at sunset, IFTTT sends a message to Wink, which then sends a message to my GE switch, which turns the porch light on.  We used to ask “how many people does it take to change a light bulb?”  In home automation, we should ask “how many products and services does it take to turn on a light?”


The Wink Relay has two buttons.  If you use it to replace a single wall switch, one of the buttons can be used for something else.  Since the Hue switch for the nightstand lamps always seems to be on my wife’s side of the bed, I decided to use it to turn off the nightstand lamps.  When you turn off a Hue light using Wink, it takes at least a few seconds to happen and sometimes MUCH longer.  People used to joke about being so tired that they could turn off the light switch and be asleep before it got dark.  In my house, that is literally a realistic possibility.

The Foobot and the Furnace

What other things might be useful to automate?  I have an air quality monitor called a foobot.  Among other things, it detects the level of particulates in the air.  If the level of particulates gets higher than desired, one suitable response is to turn the furnace fan on so the MERV 13 filter can remove particulates.  Could that be automated?

There is a foobot interface for IFTTT, but not for Wink.  My thermostat is an Emerson Sensi which has an interface with Wink but doesn’t have one with IFTTT.  (Wink, IFTTT, and all of the other players in this field are continuously adding new interfaces, so this information may rapidly become obsolete.)  However, there is a Wink interface to IFTTT.  So, having already installed the Wink hub for the porch light issue, I didn’t have to buy anything new.  A little programming set it up.  When the particulate level exceeds a threshold, foobot sends a signal to IFTTT which sends a signal to Wink which sends a signal to the thermostat to turn the fan on.  When the particulate level drops below a lower threshold, foobot sends a signal to IFTTT which sends a signal to Wink which sends a signal to the thermostat to set the fan back to Auto.

One flaw in this setup is that Wink cannot just change the fan setting.  Instead, it also sets the heating/cooling mode and temperature setpoint.  So, these other parameters get hard-coded into the automation.  If we decide to change the setpoint on the thermostat for some other reason, then Wink will set it back to the hard-coded value whenever the rule runs.  I sent a question about this to Wink technical support.  The response was that Wink programmers envisioned people doing all of their thermostat control via Wink.  I don’t want to go that far.  If this technology takes off, there will be battles over which products gets to be in control of what.

Excuse me – your door is open

The main part of the door sensor mounts on the door frame.
A little magnet mounts on the door.
The sensor senses proximity of the magnet
(except when it doesn't for some reason).
The next challenge involved our doors.  Several times since we have lived in the house, we have found that exterior doors have been accidentally left open.  (The real solution turns out to be door knobs that the dog cannot open, but that is a different story.)  Could we use this technology to get a notification when that happens so that we can go close the door?  Toward this end, I purchased a GoControl Home Security Suite that came with three door sensors.  I installed one on each of our exterior doors.  Then I set it up to send me a notification if the door stays open for more than 5 minutes.  I tested it.  It worked.  However, since then, I have gotten about ten false alarms for every time that the door has actually been left open.  Maybe I will eventually discover a way to make it reliable enough to be useful.  In the meantime, this application is a failure.

The security kit also included a motion detector and a siren.  To my wife’s relief, I haven’t hooked up the siren.  I have attempted to use the motion detector to control the kitchen lights.  The lights are programmed to go on when there is motion in the kitchen.  That works most of the time, but with enough delay that you are usually reaching for the switch by the time the lights come on.  The lights are programmed to go off when there has been no motion for 20 minutes.  That works sometimes.

What else can we automate?

There are a lot of other devices that we could add to our home automation system.  Many of our appliances can be connected to the internet and to IFTTT or Wink.  We could replace our door locks with smart locks that use Bluetooth signals to unlock when an authorized person approaches.   At the moment, we have no plans to add any additional devices until we have some clear idea of what useful functionality it will provide.


Before you choose a home automation hub such as Wink or SmartThings, look for explicit statements that the devices you have are supported.  Similarly, after you have chosen a hub, look for explicit statement that any new device you are considering is supported before you buy it.

Don’t count on home automation for anything mission critical.

If you are building new and plan to use Hue or some other type of smart light bulbs, minimize the number of wall switches.  Don’t use 3-way switches.  Whenever possible, use a single switch to control a bunch of lights.  Plan on controlling the lights through switches that work with the automation.

Plan on having lots of hubs.  In the closet where my home automation stuff resides, I have a Wink hub, a Hue hub, a hub for the garage door opener, and a hub for my weather station (which doesn't yet interface with either IFTTT or Wink).  That is in addition to the cable modem, the wifi router, and a backup drive. 

One unintended consequence of my experiments in home automation is that I have much more information about what occupants of the house do.  I have a record of what time various doors were opened and closed.  I have a record of when people walked through the kitchen.  If I chose to look, I could tell what time people turn out their lights at night.  The foobot’s air quality readings sometimes indicate activities that are outside our norms.  I have no desire to spy on my family and they trust me not to use the data against them.  For some families, this level of data gathering may cause issues.