Saturday, March 26, 2016

2016 LED Lightbulb Review

While outfitting my house with 100% LED lighting, I have selected a few bulbs that stand out among the competition. 2016 saw some new bulbs as well as price reductions. It turns out that all the bulbs I'm recommending are Philips brand. They seem to get the color right, and in my 2 years of testing I'm happy to report a a 0% failure rate among my fleet of 51 Philips bulbs. I had at least 1 Cree bulb fail, as well as 1 Ikea bulb fail.

All of the bulbs tested have passed the spouse color review process - many bulbs had immediate rejections in this phase and had to be returned. Most stores will accept returns of an open package, so keep your receipts. If the packaging says "Daylight" anywhere on it, or the color number is above 2700K, leave it on the shelf.  The brightness is measured in Lumens. a "60W equivalent bulb" is a subjective term  may be rated anywhere between 650 and 850 lumens.

Also, all of the bulbs here are $15 each or less. I'll remind you not to be cheap about this. If you need to justify the expense, add up the total cost of ownership of an ordinary incandescent bulb (including electricity costs) and you'll find that your $10 LED bulb pays for itself within 1 year.  These LED bulbs will also last over 10 years, so add in the cost of 5 bulbs that last 2 years.  Also, if you don't like the color, you have to live with it for the 20-year life span of the bulb unless you toss it and get something better, but what a waste that would be.

A Note on Dimmable Bulbs
Any time you buy bulbs for a dimmable fixture, be sure to get LED bulbs that at least claim to be dimmable. better yet, get the Philips bulbs with the "Warm Glow" feature. This feature means that the bulb changes color to a warm red glow when dimmed all the way, mimicking the color of an incandescent bulb.

If your house is like mine, you have dozens of pot lights, which are recessed into the ceiling and require the BR30 shape bulb. The Philips WarmGlow dimmable BR30 bulb puts out plenty of light and looks great when dimmed. Many stores carry these for $10 - but at my local Home Depot, the price is about $5 since my local utility subsidizes a selection of efficient bulbs.

Home Depot $10 | Walmart $10

For sockets that are under lamp shades or otherwise hidden, the opaque white plastic bulbs are a little cheaper than the clear ones.

Dimmable A19:  Home Depot $7

If they do not need to be dimmable, you can get a 4-pack for $10 at
Home Depot

Exposed bulbs or bulbs in glass fixtures need to look have a clear dome - these look great in my ceiling fan.

Home Depot $7

Chandeliers usually require candelabra base bulbs. Philips finally came out with a candelabra base bulb that is a 60w equivalent and also has the WarmGlow feature.

Home Depot $10

3-way bulbs are for those lamps that you have to turn-click twice to turn on and off. This bulb cranks out 1620 lumens when you need it, or 470 / 840 lumens when you don't.   They are also very nearly indestructible. After a 3-year-old knocks over the lamp for the 20th time, you'll see how the bulb might outlast the lamp.

Home Depot $20

Friday, November 14, 2014

All incandescent bulbs must be destroyed

If you saw an investment opportunity where you were guaranteed 100% return per year, would you take it?  Incandescent bulbs (you know, the regular cheap kind) cost far more in electricity usage than the sticker price at the store. If you have them plugged in anywhere in your home, they are unnecessarily costing you more.  If the sticker price at the store included the cost for the electricity they will consume over their lifetimes, no one would buy them.

So now for the investment pitch: replace all lighting in your home with LED lighting, and throw away the incandescent bulbs so nobody plugs them in by accident.  The LED bulbs are at least 6 times more efficient, and will pay for themselves in savings in as little as 8 months.

(read in Jim Gaffigan  audience voice)  Throw away the incandescents? That's so wasteful!
 Nope. Plugging them in and having them waste energy ever again is way more wasteful. Send em to the landfill.

The bulbs will pay for themselves in savings - it's just a matter of time.  to calculate the savings from a bulb purchase, you will need to know:

  • C = Your electricity cost.  There is a standard rate on the bill, but don't forget to add in any taxes or per kwh fees. Mine works out to $0.14 after all taxes and fees.
  • H = How many hours per day the replaced bulb is used. for this example let;'s say 4 hours per day.
  • W = the old incandescent bulb wattage (usually 60)
  • N = the new wattage for the LED bulb (usually 9.5 for a 60W replacement)
The savings per month are (H*W - H*N)/1000 * C * 30 

So in our example, the monthly savings will be around $0.85 per month.  If I got the bulb for $5 (yes, $5, at Ikea), the payoff period will be under 6 months.  Every 6 months a little green leprechaun hands me $5.  And all I had to do was replace a light bulb.  Oh, and did I mention that these new bulbs will last 20 years?

Now that you are sold on this investment, you have the task of selecting the brand and type of bulb. Here are the standard ratings that differentiate what type of light the bulb you are getting:

  • Brightness: All bulbs are measured in lumens. A 60W bulb from the dark ages puts out around 800 lumens. Anything from 700 to 900 will look similar in brightness.
  • Color:  The color of the light (or yellowness) is measured as a temperature, corresponding to the blackbody radiation spectra of a material heated to that temperature measured in Kelvin, or K for short.  Soft white is the most common at 2700K.  Bright white will be some higher number.
  • Color Rendering Index: This is the accuracy of the bulbs attempt to replicate an incandescent bulb. A score of 100 would be perfect and no one could tell the difference. Some brands advertise this number, which is a good sign that they have done some engineering to get the bulb to put off good light.
  • Dimmable: If you have a dimmer switch, make sure it says "dimmable" without the "not" in front of it somewhere on the package.
  • Enclosed fixtures: If you are installing in a closed fixture, be sure that the packaging is marked as being rated for enclosed fixtures.  The reason some bulbs will not work in enclosed fixtures is due to the heat being dissipated from the bulb. Although this is much less heat than an incandescent, it is enough to damage the bulb if it builds up in the fixture.
Here are a few bulbs that I have purchased and tested, and have found to have acceptable light color and brightness:
  • IKEA - yes, IKEA has 700 lumen LED bulbs at $4.50.  Some have a transparent case and look nice in exposed fixtures.  They have a few different styles to choose from.  Good light color and are dimmable too.
  • Phillips - In my opinion the best brand for bulbs, but not cheap.  I have Phillips for all my overhead recessed lighting.  $12 to $20 each.  Home depot stores in minnesota have some bulbs at reduced prices, thanks to subsidies from XCEL energy.
  • Feit - $6 - $12 each - Costco had a deal on these last month.  Feit bulbs were among the best rated on consumer reports.
While typing this I have completely forgotten to mention the real reason I am typing this blog, which is the fact that with each incandescent bulb that gets replaced by something more efficient, the ice caps will melt at least a little less fast.  But even if you don't believe "science", there's no denying your wallet.  

Thursday, May 16, 2013

Personal Raspberry Pi Web Server

Hasta la vista, hosting fees!  If you have a crappy website that maybe gets a couple visits per day, and you are paying more than $0.50/month for hosting, this project is for you.  The Raspberry Pi is a small computer that can run a linux web server.

Based on some power consumption measurements seen online, this device should cost less than $3 per year in electricity, assuming $0.06 per kWH

My site, is currently running in this manner, although it is a pretty light-weight on the php end, only using php include commands.  Joomla and wordpress page load times would be longer, although there are ways around this using built-in caching.

Step 1, buy a Raspberry Pi (unless your brother got you one for your birthday - thanks Eric!)

Step 2, download the latest raspbian release, and burn it to an SD flash card - you will need a card reader and software that can write an image to a flash card.  Most laptops have built-in card readers now days.  Some good instructions here on creating the SD card image.

Boot up your pi.  you can use a keyboard/mouse to do initial configuration, or you can wait for it to get a dhcp address from your router or firewall, and connect via telnet (I prefer to use PuTTY for this).
The default login details:

user: pi
password: raspberry
sudo passwd pi   
It will then prompt for a new password.

Give it a static IP.  note this IP for when you configure port forwarding on your firewall.

Next, you can run the usual debian commands to get apache or whichever web server you want to use..
sudo apt-get install apache2 php5 libapache2-mod-php5
sudo apt-get install mysql-server mysql-client php5-mysql

sudo apt-get install vsftpd

Next, take ownership of the web root:

sudo chown -R pi /var/www

Connect your ftp client to the PI, and transfer the files.  The default directory is /var/www

Now for the DNS tricks to get this to work:
Log in to your firewall - forward ports 80 and 443 to the Pi IP address.  This makes it public, but you need DNS to let people find the Pi.
Go to and set up an account.  Set up a free subdomain ( like - it will default  to use your IP address.  If your ip address changes, you will need to go back to the site to update it there, although it is a pretty easy process.  There may be a way to automate this using a cron job... or you can also install the client for windows to update the address automatically (when the computer is running)

Next, log in to your registrar (godaddy, netsol...) and forward the domain with masking to your new dynamic dns address.  The masking feature keeps the original address in the address bar, so users are not confused by your dnsdynamic address.

The change may take some time as dns changes sometimes do.  make a small change to your old hosted location so that you can tell when it is loading from the pi.  Or better yet, add a raspberry icon to the new site!

Dial up your site, and if it works, cancel the old hosting plan.  Then just wait 1 year to recoup investment in time and money.

Special thanks to others who have done this already;

Wednesday, October 13, 2010

P.S.A. that can be viewed from Outer Space!

This is what my front lawn currently looks like from across the street. A giant reminder of every citezen's civic duty. (I'm hoping that those americans on the Mir space station have a way to mail their ballots, since online voting will not be available anytime soon. )

Supplies for the project:
  1. x-mas lights
  2. extension cords
  3. a light-sensetive power switch
  4. Coat hangers

I found it helpful to start with a scale drawing, and some quick estimaions on how many lights you need. The coat hangers will be turned into cord-steaks, to keep the lettering in place. Cut off the hook, and cut the middle of the flat bottom to end up with something resembling a mini croquet hoop. If you do not have enough coat hangers, go to the local cleaners and buy a dozen for a couple bucks. I used sheet-metal snips to cut the wire, but pliers would work too. The light-sensetive power switch costs $20 or so at your local hardware store - mine has options to turn on at dusk, and stay on for 2,4,6,8 hours, or until dawn. Be sure to pay attention to how many light strings you connect in series - this maximum should be listed on the packaging. Hopefully people will not try to steal/vandalize this rig. I have a Kieth Ellison sign, and so far have caught one potential thief red handed, have put it up after having it knocked over, and had to retrive it from the alley down the street after it was stolen.

Remember; Vote aerly, and vote often!

Wednesday, September 29, 2010

Turn your Computer into an Electric Space Heater

Need a little extra heat in your house? Want to solve all of the worlds problems with minimal effort? Try leaving your desktop computer on all the time, while donating the would be wasted processor cycles to scientific research.

Go to Progress through processors to download the app and get started. The BOINC program automatically downloads and executes smaller pieces of a larger problem, and sends the results back to the lab. The program can be run with lowered security credentials, and has features that will suspend the projects when the computer is active (have it run as a screen saver). Be sure to turn off hibernation or auto-suspend.

And while you are saving the world, try signing up for WindSource (or similar program), to balance out any carbon guilt you might experience.

Note: you can only use the "house heating" argument if you live in a cold climate, and at that, only half the year. If you live in a hot climate, chances are you are paying twice as much to do the same number of calculations. Although, you may find some of these projects worth the cost and donate the energy anyway.

The waste heat from computers escapes into the room, and is just as energy efficient as any space heater. If you have the AC running, the waste heat will just make your AC run longer.

I live in Minnesota, so this is a win-win for 10 months out of the year!

Sunday, August 22, 2010

DIY Baby Toy Suspension

So, I got this baby, and she likes to reach for things, but my arm gets tired of holding toys over her, so I built this toy holder thing. I've seen these at Target for $40, but you could build this for $11 (cloth cover not included).

I purchased 2 6ft rectangular steel stock: 1/2" x 1/8" for $4.69 each.
Also, a #6 bolt , washer and wing nut for $1 .

JC sewed these green cloth covers, and secured them with bows.

The toy suspender collapses for easy storage.

The steel needs to be bent into a smooth arc, for which you will need a jig. I used a workbench with a couple of bearings bolted to it. I made the mistake of trying to bend this by hand, which put a couple of kinks in the metal. Once the jig was set up, I fed the metal through the 2 bottom rollers (pictured left) and bent it to the left of the top roller. When feeding it into the jig, The first bend made a kink in the metal, but at least it is the same for all 4 legs. The result was having 4 sections of straight metal on the ends, with the center sections having a smooth arc.
Steel will retain a camber with a curvature less than that of the jig you feed it through. If you can, increase the curvature with multiple runs. (I was not able to do this with my setup... since the adjustment knobs were maxed out with the exact curvature I needed.)

Here is the center bolt+wing nut. Use a drill bit with the same gauge as the bolt for a snug fit.

I wrapped the feet in electrical tape for safety.
If you plan on using this on wood floor, you will need to tie the opposite ends of the rods together. The downward pressure from gravity and baby grabs will cause the legs to spread out. Putting this on carpet creates enough friction on the feet.

Now for hours of baby overstimulation!

Saturday, April 24, 2010

Power your bike lights with Faraday's law!

Is this a UFO? Why do the lights blink so consistently as a function of distance? Why not just get a battery?

A project of mine for a while has been to set up a lighting system for my bike that did not require batteries. You have seen the old-fashioned Schwinns with the generator on the back wheel going to the headlight. This is the same idea, except the entire back wheel becomes the generator. As the magnets pass by the coils, the changing field generates a (small) current, in quantities defined by Faraday's law

The materials needed for this setup:

4 cheap guitar pickups
8 neodymium bar magnets (I got mine here)
8 x Nylon 1/4" bolts w/ nuts
8 nuts and 8 bolts (bolts must have high iron content.)
2 Aluminum bars 1/8" x 1/2" X 5" long to attach the guitar pickups
20' of cheap speaker cable
16 rectifier diodes
1 box of LED color christmas lights
1 x 6000uF - 15000uF 20V Capacitor (axe-man)
1x 50uF 50V capacitor
1 x magnetic reed switch
6 x 800 - 1500 ohm resistors
1 x 100 ohm resistor
soldering iron / solder
wire strippers
a breadboard for testing configurations
a volt meter
lots of spare time
I have mounted neodymium magnets on the spokes, and mounted 4 cheap guitar pickups on the rear horizontal fork. The rusty bolts seen to the left were selected for their high iron content, which helps to conduct the field to the coils (a little wd-40 would have helped stop the rust). The other side has 2 aluminum support bars, with 2 copper pipe holders to attach it to the bike frame. Aluminum was not the best choice, since the field-effect will slow down the wheels. If you find a strong plastic, use that instead.
Believe it or not, the hardest part of this whole operation was getting the magnets to stay on the spokes while riding. I used nylon bolts, since I could saw them in half and put the nut on the other side of the spoke to clamp on to the spoke. The head of the bolt is mighty-puttied to the magnet. The ones that did not fall off within a week have lasted 2 years , and I have 4 of 8 left. The wheels get jerked around when you ride, so what ever method you use to attach these has to be good. If you use glue or putty, be sure to score the magnet and bolt surface before gluing.

The other consideration is the distance from the magnet to the coil as it passes by. The closer the better, but you will find that the wheel flexes when you turn, which will change that distance and maybe even cause the parts to collide. I keep mine about 5-8mm away.
Once the coils and magnets are mounted in place, the next step is to start on the circuitry.

Step 1: build a rectifier circuit that will take the AC pulses from the coils, and smooth them out with a low-pass filter to a safe DC voltage for that mega-capacitor you bought. Here is a crude circuit diagram (anyone have a good free circuit-drawing tool that runs on xp?)

The squiggles are the coils (there are 4, but I only drew 2...), representing an AC voltage source.

The arrows with the lines are the rectifier diodes. Each wire from a coil gets 2 diodes opposing in polarity. match all the diodes of 1 polarity together to form 2 main leads coming from the coils (a + and a -)
Step 2: the low-pass filter
The 1st capacitor on the left is the 50V/50uF - make sure this has a rating of 50V or more, since the coils can produce spikes that will short out smaller caps. The 100ohm resistor drains the voltage to the main cap between spikes.
Step 3: charge the main capacitor:
The Main cap should have a rating of 20V or more, with 6000uF of capacitance (for those confused while shopping, MFD is the same as uF ) Get the capacitors attached to the breadboard , and get the polarity figured before you solder anything.
Step 4: the magnetic reed switch:
Attach the magnetic reed switch on the rear fork somewhere in the vicinity of a passing magnet. This will be the strobe driver for the lights. As you can see on the left, electrical tape works just fine to secure this light-weight component. When in the presence of the magnetic field, the switch is pulled to the closed position.
Step 5: testing out the lights:
This next photo shows the breadboard in use. You can mix-and-match to a certain degree with LED's, but using only the LEDs from the xmas lights will allow you to assume that all of the lights have the same voltage drop and current draw. The 6 800-Ohm resistors are for equally dividing the current between all the LEDs, and keeping the lights from draining the capacitor right away. To organize this, I soldered a collection of 5 resistors to the positive lead of the main capacitor, and attached the wires going to the diodes from there. The advantage here is that a pair of diodes can share a negative lead, requiring only 3 wires for 2 led's. I put 2 LEDs in the back, 2 in the middle, and 1 in the front.

Step 6:
Solder the connections and manage the wires. - Be sure that the wires do not interfere with the break or shifting cables. Electrical tape works well. Get the wires in place and taped before soldering. wires that ware twisted together will not stay that way (and the oxidize too), so soldering is mandatory.

  • The LEDs are polar, so be sure to keep track of this when soldering.
  • mark the polarity on the wires to save time. (often I will use copper for positive, and steel for negative)
  • If people start conversations with you about how this is "green", inform them that far more energy went into the manufacturing these components than will ever be generated by them. My computer has even surpassed the amout generated while writing this blog. If your friends want to be green, have them all write a letter to our delegates urging them to cover Minnesota in windmills and solar panels, and to pay for it by taxing carbon.
  • don't try to look at the lights while riding, as this can be distracting and cause accidents.
  • have someone take a long exposure photo of you going by at different speeds.