Which Slice To Eat First?


[ Source: Oregon Department of Environmental Quality and EPA ]

Via Sightline, the 2005 U.S. greenhouse gas (GHG) emissions chart above illustrates an alternative way cut the pie, emphasizing the importance of goods and materials, and suggesting we ought to look at ways to use less stuff. But to intelligently assign priorities, it’s also helpful to know how challenging and costly it would be to make a given GHG source reduction. Behold the most excellent diagram below, via Worldchanging:


[ Source: The McKinsey Quarterly ]

The bars going negative indicate that the GHG emissions abatement measure actually saves money overall — free lunches, so to speak, i.e. no-brainers, one would think.

Note that four of the five most cost-effective measures address energy use in buildings. And now take another look at the chart at the top of the post and mark the second biggest slice of pie. And while your at it, ponder this analysis that attributes an even higher portion of GHG emissions to buildings. Translation: buildings are low-hanging fruit and there’s a lot of that fruit, and thus should be a focus for cutting GHG emissions.

(Also note: Increased fuel efficiency in commercial vehicles could potentially help put a dent in the emissions related to the provision of goods and services.)

20 Responses to “Which Slice To Eat First?”

  1. dorian gray

    Lighting systems will be easy once we get LED’s out in force.Unlike traditional light bulbs they dont waste energy heating up the bulb uselessly (imagine not getting burnt when touching a light bulb) and hence require less energy to light the filament.

  2. Tony

    Not that I want to do too much to encourage your communist dream of stacking us on top of each other (joke), but do you have any data on the relative energy efficiency of large multifamily vs. detached single family structures? Of course we all know that density saves GHG on transportation, but wouldn’t it also be cheaper to heat a single dense structure rather than several detached ones? Wouldn’t it also take less energy to construct the same number of multifamily units due to economies of scale in energy? It’d be great if you could get some hard data on that, but this could be one more angle which you could use to beat the NIMBYs over the head. :-)

  3. Matt the Engineer

    [Tony] Here’s a aggregate data for housing energy use throughout the US by component load. It doesn’t get you all the way there, but you could certainly argue (for instance) that with 1/4 the window, wall, floor, and roof area you’d be saving 29% of your heating energy.

  4. Dan Staley

    I second Matt’s assertion. I have a number of texts that have savings figures that are close to this number. Takeaway: SFD homes are the biggest of the residential wasters, by far. And SFDs on big lots are even worse ecologically, contributing more to the urban heat island and goop runoff into receiving waters.

    And while your at it, ponder this analysis that attributes an even higher portion of GHG emissions to buildings.

    My rule of thumb is about half.

    Now look at the ‘food’ pie. And the recent studies that put transportation GHGs for food at about 1/5 of all emissions.

    In my mind, focusing on ‘locavores’ and finger-wagging about food miles is distracting away from the work to be done.

    Why? As soon as oil is steady at ~150/bbl, production will natually get differenter, as we eat so much oil, by way of fertilizers, machine planting and harvesting, etc.

  5. gw

    Dorain- LED’s show lots of promise, and while they are far more efficient than incandescents and cutting edge LED’s have overtaken modern fluorescents, they still emit lots of heat. In converting electricity to useable light, LED’s are only ROUGHLY (don’t quote me) 20% to 40% efficient. Where does the rest of the electricity go? HEAT. An LED array capable of lighting up a room (not your LED flashlight), can reach a skin blistering 160°F. Heat dissipation is a huge obstacle for mfg’s, heat sinks are huge and overheating significantly reduces output and shortens their life.
    -Greg the (electrical) Engineer

  6. Spencer

    Matt and Dan,

    Arguablly it would be a much larger savings when looking at the data by unit? With less exterior surface per unit there would be less solar gain, less infiltration and even less floor and roof area. The study to make those graphs does take into account multi-floor housing in addition to single family and townhouse. It even considered mobile homes too.

    Do you guys know of any good sources for energy usage for Multifamily buildings in the Pacific NW? I’m working on a analysis of multifamily development comparing non-LEED rated buildings to buildings constructed using LEED requirements.

  7. Matt the Engineer

    I don’t have a source for NW multifamily data. I know California has done some good studies, but the climate’s too different to use here.

    The LEED part is easy. Try the table on page 20 of this report (pdf), which compares LEED buildings to CBECS (a national survey) buildings. The energy used in multi-unit residential buildings with a LEED certification is 49% of the average multi-unit residential out there (though it isn’t broken down by location – maybe contact the authors?). The only large caveat is that average non-LEED housing stock has got to be much older than LEED building stock.

  8. Dan Staley

    Do you guys know of any good sources for energy usage for Multifamily buildings in the Pacific NW? I’m working on a analysis of multifamily development comparing non-LEED rated buildings to buildings constructed using LEED requirements.

    Spencer:

    I’d contact Eric or Clark over at Daily Score or Cascadia Scorecard or whatever they call themselves these days.

    Anyway, a graphic I like to use is found on pg 148 of Sustainable Residential Development by Avi Friedman. KWh estimated heat loss for SFD: 11754, duplex 11291 (34% reduction), rowhouse 10761 (26% reduction).

    Another good text is Cities as Sustainable Ecosystems by Newman and Jennings.

  9. dan bertolet

    Spencer @5: I am working on a similar energy analysis and there is very little data available on multifamily buildings in the Pacific NW. I’d like to talk to you about what you’re doing. Send me email at hugeasscity@noisetank.com with your contact info.

    gw @4: Whether it’s a fluorescent or an LED, any input energy that isn’t converted to light is lost as heat. True that LED output and life drops when they get hot, but my guess is that a typical fixture can absorb enough heat so that it’s not an issue.

  10. Dan Staley

    There’s also an interesting general overview in the new CNU Green Council Report, pp 15-16. Not region-specific, but not bad for understandable context either.

  11. gw

    RE: Dan@9: Yes, LED overheating isn’t an issue, but this is only because they were designed that way. So, in a way, it is an issue. No?

    I was fascinated by the most excellent bar graph above, but I’m still confused. Are there two different measurements occurring on the horizontal axis? What are they? Regarding the zero line on the vertical axis- Dan are you saying/as I read it- items below the line pay for themselves and items above the line would require, say, a government subsidy to realize their abatement potential?

  12. Matt the Engineer

    It looks like the y-axis is cost to remove a ton of carbon dioxide, and the x-axis is abatement potential in giga-tons of carbon dioxide. We actually make money on anything under the zero line, and it will cost money over that line (could be subsidy, or we could fairly price carbon). What I like about this chart is that you can easily see how much it will cost to get to carbon dioxide goals (the 550ppm and 450ppm), including an estimate to get to 400ppm (though we don’t know how yet).

  13. gw

    So- On the x-axis, the total cost to reach a goal is found by summing the cost per abatement item (area of the bar- cost/ton*gigatons = cost) for each bar to the left of that goal. No?
    The y-axis is a net cost to the whole economy? Spend money on building insulation and save even more on energy costs. Conversely, throw enough money at Biodiesel to make it sustainable and save only CO2.
    So with all these “freebies”, what’s the holdup?

    This graph caught my attention b/c my own research in alt energies/conservation for my 850sf SFD have repeatedly let me back to the same three strategies: insulation, insulation and more insulation. I am really interested in supporting the burgeoning solar thermal industry with a purchase (taking advantage of the expiring tax credit), but recently I’m having second thoughts- and the graph reinforces that. Maybe all that money is best spent on plain-old boring insulation?

  14. Dan Staley

    Maybe all that money is best spent on plain-old boring insulation?

    Yes.

    Spend some time in a straw bale home or one that is well-insulated (say, R-30 walls) and designed for passive solar (OK, not the best idea in western WA state, but still) and you’ll see why.

  15. Matt the Engineer

    Insulation will get you pretty far in our climate. Don’t forget about your windows – you lose a lot of heat through them. Go Low-E and consider triple pane for new construction. Blocking air infiltration is another energy saver (I wonder if SIPs are catching on here), but at some point you’ll have a problem with ventilation – the solution there is a heat exchanger on your toilet exhaust to makeup air.

  16. gw

    I wish I knew someone who owns a house actually insulated at or above code minimum!

    Insulated glass, major infiltration remediation and a heat recovery ventilator are all on my list.

    I wish you could remodel with SIP’s. The thought of how much easier it would be to just build a new house the way I want it just kills me. It’s frustrating to see new construction in my neighborhood going up pretty much like it did, well, 100 years ago. OK so you weren’t required to have insulation back then, but if you did it would have looked the same. Does anyone else think that not much has really changed?

  17. gw

    “I wonder if SIPs are catching on here” Interesting you should pose that question Matt. You included a link to sips.org, which as it turns out is based in Gig Harbor.

  18. fruit machine jenny

    the comments here are having a laugh – i’ve added your blog to my netvibes account, keep up the good work :)

  19. Master Spa Parts

    I enjoy keeping up to date on everything different so I’ll unquestionably be bookmarking this site.

  20. Culver City Chiropractor

    Culver City Chiropractor…

    Which Slice To Eat First? | hugeasscity…

Leave a Reply