Monday, October 27, 2008

Motion sensing

Don't get me wrong, I'm all for using motion sensing to improve lighting. At my previous office we installed motion sensor switches most everywhere, and the lights definitely were off a lot more. Bathroom lights tended to get left on all night and weekend, and the lights in out of the way places that people were too lazy to turn off also benefited from the motion sensor switches. However some of them would repeatedly get set back to manual. The motion sensor wasn't always good enough (so that when you were behind the server rack it didn't see you and turned off the lights and the delay was set too short). I recall that we paid about $30 for the drop in switch replacements like these
though amazon seems to have some cheaper options like this
Current cons include: jerkiness of on and off, having to wait for lights to flicker on (esp. fluorescents), extra costs of the sensor switch, sensor switch getting blocked by furniture, sensor switches getting turned on by pets or breezes outdoors. Also the first one I link to, a certain percentage will die after some amount of time and require replacement.

Note that the replacement switches are the most unobtrusive, but they don't always lend to ideal placement for the sensor. Also you need an electrician to do the replacement (though certain electrical engineers I know have done the replacements yourself, though I don't recommend it as death or hair standing on it's end can occur -- remember once you let the smoke out of your electrical system it's very hard to get it back)

My motion sensor dream:
Switch would have off, auto, 10% auto, and on.
Auto would leave the light off until motion is detected, it would quickly ramp the light from 0 to 100%.
10% auto would leave the light at 10% (so you can vaguely see and not trip) and quickly ramp to 100% when motion is detected.
When leaving a room it would gradually lower the light from 100% to either 10 or 0% depending on the setting.

I think these features would eliminate a lot of the issues that people have with motion sensors lights.

Also, a lot of houses have motion sensors already for alarms, can we build off that somehow? For that matter the alarms also know when you enter and leave a house, that could tie in to a turn off all the lights when you leave sort of scenario.

For those with incandescent sockets: screw in motion sensor

or those with plug in lamps: pluggable motion sensor

Please note that I didn't do extensive searching on amazon for the best, I just found the ones I originally bought and amazon recommended the other 3.

Note, there are cheaper generic versions of these sensors findable on google products results, though they are from unknown suppliers and unknown stores, but please report back with your findings and let us know good ones that are cheap!

Battery powered light turn-er off-er

So um yeahhhhh. While I agree with the goal of this thing, making a battery power motor that physically flips switches for you doesn't seem to be the best way to go about doing things. How much more resources does this take than a standard motion sensor switch combo? However for those that are unwilling/unable to replace their existing switches I guess that you could over come the battery power requirement and construction requirement to save net energy. I'm sure this will be available soon in skymall.
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Well, actually it's quite a neat gizmo—it's battery powered, and simply mounts directly over a light switch, which it then throws for you if it doesn't detect movement in front of its sensor. Plus it turns the lights on when you enter.
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Friday, October 24, 2008

Boeing 767 - 60 gallons to london

Ok, I know the comparison isn't totally valid (because you wouldn't be able to drive your car to london), but I still think it's fun. Though this is probably assuming a 100% full flight, and you have to compare the trip to not going at all but... my gut says pretty fuel efficient and those people blaming the aviation industry for global warming should be looking elsewhere!
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  • It takes approximately 60 gallons of fuel per passenger to get from New York to London on board a 767-400ER. The same volume of gasoline would propel an economy car about half of that distance!
  • The noise level of a Boeing 767 taking off from a 1.5 mile long runway is about the same as the average street corner’s traffic noise.
  • Here are some interesting facts about Boeing 767s:
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    Tuesday, October 21, 2008

    Fiat introduces usb drive and software for improving your lead foot

    This is *so* in the spirit of this blog. Collecting data to help you improve how you do things so reduce our resource consumption.
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    The program will measure a driver's fuel consumption, speed, braking style, and even how efficiently he or she shifts gears with their manual transmission. It seems very similar in functionality to the PLX Kiwi from PLX Devices that plugs in to a car's diagnostics port.

    Blue&Me is an onboard computer system currently offered in some Fiats and Alfa Romeos, and possibly soon, in Ford cars, as well. It enables drivers to listen to their MP3 player, make calls on their cell phone, and have text messages read aloud to them. The system includes a USB port, which Fiat has announced could be the key to a 15 percent reduction in a car's CO2 emissions.

    But exactly how bad are drivers when it comes to abruptly starting and stopping? And are they really shifting their manual transmission car correctly for optimizing fuel?

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    Tuesday, July 15, 2008

    Cheap programmable thermostat

    Techbargains links to a sale on a already cheap programmable thermostat. If you don't have one already this is one of the fastest ROI (return on investment) eco friendly products out there. Drop the temp at night in winter and during the day when you are at work. Raise it during the summer.

    HUNTER 44260 Programmable Digital Thermostat $28.54, Jul. 15 10 AM

    $3 less on top of sale price amazon has the HUNTER 44260 Set and Save Programmable Digital Thermostat for a low $28.54. Free shipping. Tax in KS, KY, ND, WA, NY.

    Compare Prices | Email Deal | Similar Deals | amazon Coupons | Comment

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    Thursday, July 10, 2008

    Streetlights with motion sensors!!

    Ecogeek reports sharp is coming out with streetlights with motion sensors, but wait before you join me in my hallejulahs, the motion sensors, wait for it..........don't seem to be used to turn the lights off! They seem to be used to sense earthquakes to turn the lights on when there is no power (I guess a normal power outage isn't enough to qualify for turning on)

    Please somebody be less lazy than me and read the original article and tell me I'm wrong and these turn off when nobody is moving around them...

    UPDATE looking at the page translated by google for the product it doesn't seem like they turn off the lights when no motion. Booo.

    Still though, it's nice that they are touting the low energy consumption

    Wednesday, July 9, 2008

    speed vs. mpg (aka 55 in the left lane?)

    I have been more and more people saying they are driving slower to reduce their gas usage. Further evidence that market economics work, (insert rant here on why we don't include all the market costs like future environmental cleanup and to build mass transit to reduce demand so that money goes to infrastructure rather than exxon)

    However, as always, I say make the changes that make the most sense.
    When I heard a friend describe a relative as complaining about the 55mph minimum speed limit being too high because he wanted to drive his prius slower, I had to address mpg vs. speed here.

    Each car has it's own mileage to speed continuum. However, for most cars it looks something like the graph below from fueleconomy where it starts to go down after a certain point.
    A large factor in this is wind resistance, so cars that are like big air dams (pickup trucks cough cough) are going to have a lower speed at which mileage begins to decrease rapidly. More aerodynamic cars like the prius are going to have a higher point. A forum poster graphed his mileage in the prius here and claims that the speed of diminishing fuel savings is around 70mph.

    So yes, you get better fuel mileage driving more slowly, but it really depends on the speed. So slowing down from 75 to 70 will save in just about any car. Slowing down from 65-60 in some cars, and 55 to 45 will not save nearly as much) Wind resistance goes up as the square of the speed so the higher the speed you'll use significantly more. This is why race cars are so intent on drafting (though I don't recommend drafting on semis, you don't get very good gas mileage when they have to slam on their brakes and you end up smashed, though I guess if you survive and are attached to their truck and your back wheels still work and you are going where they are...)

    Plus as always here at "tha metric" we have to consider the other external costs. What about the drivers with road rage behind you that have to make an extra trip to the hospital for their blood pressure? c.f. Denis Leary's song lyrics: "I drive really slow in the ultra fast lane
    While people behind me are going insane"

    and would you do more for the environment by getting there 10 minutes earlier and spending those ten minutes planting a tree?

    Answer due in homework bin by friday.

    PS to clarify any agenda you may think I have or do not have, I generally drive the speed limit, as I think speed differential is dangerous but I also want to get there today and not use too much gas.
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    While each vehicle reaches its optimal fuel economy at a different speed (or range of speeds), gas mileage usually decreases rapidly at speeds above 60 mph.

    You can assume that each 5 mph you drive over 60 mph is like paying an additional $0.30 per gallon for gas.

    Graph showing MPG VS speed MPG decreases rapidly at speeds above 60 mph

    Eco-feedback for better gas mileage

    An interesting new device (at least interesting to those of us who are interested in measuring power consumption of lamps in hotel rooms we visit) comes across the rss reader of electrimetric headquarters.

    It uses the principles of biofeedback (which in my mind are: that which we can measure we can learn to control) to try to get us to save gas. It tells us our current mpg, logs it and records it in novel ways to give us driving challenges.

    I have found my own little obsessive game with my trip odometer which tells me average mileage, which I have stopped resetting so that I have less control over the mileage so I don't spend my whole drive worrying (little changes with large divisor make littler changes).
    An even simpler game comes with the "eco mode" light. a little green indicator that tells me my car is using only 3 of it's cylinders. I recall that toyota has decided to put "eco mode" lights in all their cars (saying when you are using small amounts of gas) as they have found people drive better when they are reminded they are doing well. question of the day: compliment people when they are eating a little and they will lose weight?

    Anyway, this new product provides even more encouragement for you to lose weight on the foot pedal (metaphorically speaking).
    However it will lose weight in your wallet as well.
    At $299 (cnet offers an alternative product that does less for $169) I would have to save 10% of my gas mileage in order to pay back the $299 in a year (assuming 10000 miles driven and 32mpg, your mileage may vary )
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    By plugging into a vehicle's diagnostic port, it can display miles per gallon as well as trip information and even the cause of engine problems.

    But really it's designed to make your driving habits more energy-efficient.

    The PLX Kiwi shows off feedback on how you're doing in that regard and gives you a "kiwi score." It's also programmed with 20 increasingly difficult challenges to optimize your score.

    Tuesday, June 3, 2008

    LED street lamps

    According to tree hugger Dusseldorf Germany has decided to replace 10000 of their gas street lamps with LEDs. They bring up the excellent point LEDs are more directional which will save on light pollution as well as energy. I still don't understand lack of motion sensors though!
    Especially with LEDs that are quick to turn on and off (unlike high pressure sodium vapor) and LEDs are dimmable (when no motion only use 1 in 10 LEDs)
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    Of course, LED are still kind of expensive, so there's a capital cost. But once they are in place, their operating costs are lower and they can last for a very long time. Another benefit is that you can direct light much more easily, so you can avoid sending light in all directions (people with a street light across the street from their bedroom window will understand...). The first bump in the road for LED street lights was that some people thought their white light was too cold compared to the red-ish glow of the old lamps, but that can easily be fixed by using colored LEDs. ::Replacing gas lamps with LEDs

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    Saturday, May 31, 2008

    FedEx hybrids

    Spotted in San Francisco in May

    I recall reading somewhere they have purchased 200 or so (a small percentage of their fleet anyway).

    But certainly it seems like local delivery trucks are an area where hybrids would be more resource conserving than highway driving

    Friday, May 30, 2008

    Quantitative eco statement of the day - Flying versus driving

    <b>$15,000 for a Airbus A320 to fly from New York to Long Beach.</b> The article cites $3.50/gallon for aviation fuel => 4285 gallons of gas. Google maps says it would be 2827 miles driving => 1.5 gallons of avgas per car mile. A car can hold 4 people where as an a320 can hold 150 people in a typical us carrier configuration. So to equate to the same efficiency as driving in a theoretical 30mpg car, you'd have to have 80 people on board that A320. Given that load factors are in the 70-80% these days, you could easily exceed that.

    Of course that's assuming people would be driving if they weren't flying and ignores the fact that google says it's 42 hours driving time so there would most likely be some rest stops, hotel stays, food etc.
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    Any kind of cost savings is vitally important at a time when the cost in fuel of flying from New York's John F. Kennedy International Airport to Long Beach has jumped to $15,000 a flight from $9,600 last year, according to Baldwin. That change makes adding Los Angeles International service unaffordable, Baldwin said.

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    Quantitative eco statement of the day

    I am going to start posting a series of quantitative statements about resource consumption that I've run across. I haven't fact checked them at all, so take them as they are intended to be: an interesting look at the different numbers being used on the web to discuss resource consumption.
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    You think you hate sitting on the runway couped up in a plane that seems to be going nowhere. Well, the airlines (and the planet) hates it too. In 2007 $1.6 billion of jet fuel was burned by planes waiting in line to take off at airports. That's 740 million gallons of fuel.

    And from the perspective of climate change 7.1 million metric tons of CO2.

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    Tuesday, May 6, 2008

    View of Eath Lights at night

    In my last post I mentioned lights at night. Long time readers know I've whined about streetlights and their waste of electricity (and their lack of motion sensors). This incredibly beautiful poster (composite image of earth taken at light exposed for the lights and merged with landforms, clouds removed) definitely influences my opinion on street lights, as do the plight of the astronomers dealing with light pollution or merely sitting on my back porch unable to see the stars most nights.

    However on the flip side, I have enjoyed flying over our beautiful country staring out the window, and the shapes of our cities outlined by lights is as entertaining as the view of all the landforms (and both are more than the in flight movie that has been very edited for objectionable content)!

    I often try to take pictures of the lights of the city as we are landing but the exposures are so slow that the lights blur (though that can be a cool effect -- see images at left )
    Anyway, I have seen cities that look like neuronal cells, cities that are very grid based, cities that clearly illustrate the underlying geographic forms and cities that outline new development by the color temperature of the newer streetlights. But I haven't been able to capture these images to share. However NASA seems to have figured out a stable platform from which to take these pictures (they are a bit higher orbit than united airlines flies!)

    My pics:

    Note: images are copyright bryn forbes 2007

    Map of just roads

    Here's a very interesting image made from drawing all the maps in the US on the map. It has a similar effect potraying how much of the natural habitats we have made an impact on, as the nighttime view showing all the lights. Of course in this case the rural areas with a road around 40 acre plots is a lot less of an effect than the dense areas.

    Thursday, May 1, 2008

    Another giant yellow hybrid
    Speaking of giant sized hybrids that are yellow, GE is making hybrid dump trucks. Now that's what I need for the trips to the grocery store!

    Wednesday, April 30, 2008

    Hybrid school buses!

    I found out a friend works for a company that make hybrid school buses!
    Check em out here

    they claim 70% improvement!!!

    I hesitate to mention this in case people buying hummers think they can be green (or in this case yellow) and have a hybrid SUV (schoolbus utility vehice)

    Tuesday, April 29, 2008

    Lower mercury CFL bulbs

    Don't count CFLs out you scrappy LED upstart you!

    New CFLs have less than 1.5 milligrams of mercury (normal have 5mg). (There's a snide remark about tuna having more in here somewhere -- though I'm refraining since I don't have data for fish bulbs)

    Though you have to worry when technology starts to integrate other gadgets (alarm clock/golf bag anyone?) so maybe CFL manufacturers are starting to worry since one is making a CFL that makes your room less smelly (sure to be sold at sharper image if it wasn't bankrupt)

    13W LED bulb
    Treehugger reports on a 13W LED bulb as replacement for incancdescents.

    It's interesting that it so much more efficient than an incandescent (which wastes most energy as heat) but has a fan inside of it to reduce heat.

    They also tout other features of LED long life bulb, less mercury than cfl, etc.
    But cost cost cost cost cost?

    How many watts hours of solar electricity could you buy for the cost of this bulb?

    Thursday, April 24, 2008

    Motion sensor lighting

    Posted by ShoZu

    This was a cameraphone pic I shot in the hallway of a very very large apartment building in mid town manhattan. Every other light fixture was motion sensitive. Most of the lights near the elevators were constantly on but the ones near the ends would definitely be off most of the time.

    Wednesday, April 23, 2008

    Plug in hybrids better for the environment despite being coal powered?

    I've often snidely remarked that plugin hybrids are coal powered, but it seems I will have to change that. Here is a link to an article by EcoGeek with some data claiming that they end up being better for the enviroment overall despite the eletrical transmissions losses.

    Thursday, April 17, 2008

    Per capita CO2 emissions

    Check out this map of per capita CO2 emissions.

    UPDATE: I showed my texas geography ignorance and slandered houston, my apologies!

    Wednesday, April 16, 2008

    how much energy is your city consuming?

    Infosthetics notes a idea to project how much energy a city is using on the plume of a coal power plant for all to see.

    Electrimetric was created with the idea that if we know how much energy we use, and see feedback based on changes, we will reduce our resource consumption. The question is would this help because it reminds people how much energy they are using? or hurt because they see turning off their light is just a cigarette amongst the coal power plants pollution.

    It seems like you could do this via a web page reporting how much energy your city is using, and I'm sure there are things like this out there. Avid readers, send those links in!

    Monday, April 7, 2008

    Dark Vader

    A friend was telling me about her father who would proclaim himself "Dark Vader" with an innovative power saving technique. If she or her family left the lights on, he would unscrew and take the lightbulb. Certainly solves the problem of leaving the lights on from then on out! I guess you'd learn pretty quick or else you would leave the switch on all the time but not use any energy (hope you ate your carrots!)

    Apologies to the folks at Buy Star Wars Costumes for the bastardization of their image.
    Also the artists at
    Star Warped

    Tuesday, February 5, 2008

    Concept home power monitoring system

    I've wanted something like this for a long time. It's just a concept, but would be very cool. I would want to make sure that the monitors don't end up using more power than you'd be able to save by having the information, but for a quantitative data geek like me, cooooool. The Greener Grass via

    Wednesday, January 30, 2008

    Playstation 3 measurements revisited

    erac3rX (who is working on a killer gaming setup -- site coming soon at
    writes with measurements of the older revision of the playstation 3 to compare to the new revision in the 40GB PS3 posted here

    Note the interesting difference between cold start and hot start on booting. Are there really 15 watts or more of fans running? Wow!

    PS3 (60GB, one of the latest manufactured)
    Off: 1
    Booting (cold): 140-145, max 156
    Booting (hot): 158-160
    Menu (XMB) (cold): 156 at login screen, 163 after logged in and ticker tape running.
    Menu (XMB) (hot): 167-169 waiting to login, 175 after logged in w ticker tape running.
    Resistance Fall of Man: Cut Scenes: 163-164
    Playing first level of RFOM: 180-185, peak 190
    RFOM paused: 158-159
    Loading Bluray/Menu: 169
    play Bluray (House of Flying Daggers ch 14): 169-172
    30x Fast Forward: 167-169
    Paused bluray: 166-167
    Running Folding @ Home: 191 w/ active visualization, 175 screensaved
    Web page loading sony store page: 167-169

    Friday, January 25, 2008

    Time Lapse energy video

    Check out this time lapse video It's not very quantitative, but it's quite cool. Even if you don't appreciate the message (it's similar to inconvenient truth in it's message) there is very cool imagery in there. The photographer made the video using still photos taken at intervals to make time lapse sequences in black and white.

    Thursday, January 10, 2008