[GSBN] Embodied energy comparisons

Fri Feb 20 18:17:52 UTC 2009

Ah, and here I was about to dismiss transportation costs myself.  I have to
admit to getting a bit irritated when I see absolute limits put on how far a
material is "allowed" to be shipped in order to be "green."

Your example makes sense when you think about it--the piers are 1/20th the
material, even if the cement (1/100th) was sent by boat from Asia.

The figures are very interesting: a cubic yard of concrete is equivalent to
the fuel to send a freight truck 108 miles.

John

On Thu, Feb 19, 2009 at 2:45 PM, Bruce King Ecobuild <
bruce at ecobuildnetwork.org> wrote:

>
>
> A note on transportation energy, of which Andrew is a bit dismissive.
> I was also dismissive, until I did a calculation for a specific job (my
> report excerpted below in red after my signoff tag).  I had assumed that
> reinforced concrete was so energy intensive that any- and every-thing should
> be done to minimize its use (no easy task here in shaky California).
>
> What I found was that I was not only wrong, but VERY wrong.  Transportation
> energy was HUGE, at least when discussing the movement of heavy stuff (earth
> and rock) into and out of a dense urban area (ie, pretty far, and by truck).
>  My simplified conclusion is to confirm what is now enshrined in various
> green building standards such as LEED:  keep it local.  That axiom becomes
> more true the heavier the material is, and conversely less so with light
> materials.  If the best instant hot water heater happens to be made on the
> other side of the world, go ahead and get it, no big deal.  If, however,
> you're talking about moving dirt, or the heavy structural and finish
> materials, then localize vigorously.
>
> Here in the USA, we routinely ship framing lumber in great quantity over a
> thousand miles to its sales and use point, such as where Derek lives in New
> Mexico.  In San Francisco, we import gravel -- GRAVEL -- a thousand miles
> from British Columbia for our concrete.  The system, in other words, is
> massively dependent on cheap oil.  That maybe made sense for our parents'
> generation, but not for ours, and certainly not for all of those generations
> -- of all species -- yet to come.
>
> My two cents.  I really appreciate everyone's posts.  This is no simple
> subject, but we do need to think these things through.
>
> Thanks,
>
> Bruce "a still vigorous local" King
> (415) 987-7271
> bruce-king.com
> ************************************************************
>  . . . the foundation discussion of a drilled pier system or not resurfaced
> last week as excavation and site clearing began.  We have always shown
> drilled piers in the drawings where the structures are over an appreciable
> amount of fill, but decided -- after much deliberation -- to omit piers in
> the more stable, "cut" portions of the  foundation.  I had led the charge
> away from piers on the assumption that the saved concrete and rebar amounted
> to the greener way to go;  Mark Baumann and Andy Murray [geotechnical
> engineers] tentatively concurred, and we crafted a foundation that worked in
> every sense of the word, based on that assumption.  We were operating on
> instinct and judgement, as no one had ever (to our knowledge) ever even
> tried to make any sort of apples-to-apples comparison for something like
> this -- at least from an ecological perspective.   The resulting design, as
> is currently shown on the drawings, requires the overexcavation and export
> of a three foot layer under the cut areas, which volume must then be
> backfilled with imported, compacted baserock.
>
> Spurred by recent onsite discussions, Mark and I set out to put numbers to
> this.  Specifically, we worked with the excavator and concrete contractor to
> determine the dollar and carbon costs that would be associated with a switch
> to an all-piers/no-overexcavation foundation.
>
> We were very surprised.
>
> It turns out that eliminating the 800 cubic yards of
> overexcavation/backfilling, and adding about 40 short (eight feet deep)
> drilled piers (21 cubic yards of reinforced concrete), has the following
> effects:
>
> *1) Dollars*
> Save about $100,000 in excavation, export and import costs.  Spend an
> additional $35,000 for drilled piers.
> *Net savings $65,000*
>
> *2) Carbon emissions* (figures taken from multiple cross-checked sources,
> e.g., EPA)
> Save 70,000 pounds of carbon (!!!) associated with burnt diesel fuel for
> excavation, export and import costs (3120 gallons of fuel at 22+ pounds of
> carbon per gallon).  Spend (emit) an additional 8400 pounds of carbon for
> drilled piers (21 cubic yards at 400+ pounds carbon per cubic yard).
> *Net savings 61600 pounds of carbon*
> ************************************************************************
> On Feb 19, 2009, at 12:11 PM, Graeme North wrote:
>
> More from Andrew
>
> Interesting notion of Andrew's that local doe not matter - I think it
> really does matter for reasons of building local economies and resilience,
> and for shortening local feedback loops - using a distant PVC plant to make
> your stuff does not seem justifiable to me in any other terms expect those
> Andrew puts forward below - there's more to our choices than carbon storage
>
>
> By the way - trees are not nearly as good at carbon storage as healthy
> pasture which stores carbon in the soil - (which it seems is where most of
> the carbon in the world is stored).  So much for carbon guilt credits by
> asking someone somewhere to plant a tree for you - especially when good
> pasture is used for the plantings unless in a very integrated holistic
> system of husbandry.
>
> No easy answers
>
> Graeme
> Graeme North Architects
> 49 Matthew Road
> RD1
> Warkworth
> tel/fax +64 (0)9 4259305
>
> graeme at ecodesign.co.nz
> www.ecodesign.co.nz
>
>
> Begin forwarded message:
>
> *From: *Andrew Alcorn <jandrew.alcorn at gmail.com>
> *Date: *19 February 2009 8:14:41 PM
> *To: *Graeme North <graeme at ecodesign.co.nz>
> *Subject: **Re: [GSBN] Embodied energy comparisons: SB vs Stick-built*
>
> Hi Graeme
>
> Joining the list sound sensible... I did use to be on it, or it's
> ancient equivalent, over a decade ago.
>
> Andrew
>
> Hi Tim
>
> All good ideas - your list. Unfortunately, intuition isn't a reliable
> indicator of sustainability performance. Even after years of work in
> this field, mine's been seriously caught out more than once.
>
> Straw bale works, even with more concrete footing and more roof. Of
> course, a timber floor is better again.
>
> As a long-time embodied energy researcher, I feel entitled to proclaim
> that embodied energy is not the best way to measure sustainbility. It
> has its uses - its good in making comparisons. Actually, money is
> pretty good, but that requires more work to be able to say exactly how
> good. Money captures lots more aspects of the (damaging) human
> enterprise than energy does. Teddy Goldsmith (The Ecologist) captured
> this when he declared that the environment will not be saved until the
> economy collapses. But that all opens another, larger, can of worms...
>
> Measureing performance in a whole-wall way is a good idea. But,
> actually, you need to do it in whole-house way. That's when you find
> stuffing as much carbon-storing material in as possible is the best
> strategy.
>
> Small needs to be related to the number of occupants. If you go
> *slightly* bigger, but include another person into the household,
> that's better. Comparing houses on a per-capita annulised basis is the
> only reliable way I know of to make accurate comparisons.
>
> Longevity is important. If you can get each item in the house to last
> longer, then you use fewer resources to do repairs and maintenance
> over the life of the house. Hence, materials that don't need painting
> are good. The exception to this rule, curiously, is carbon based
> materials (timber and SB). If you replace them at more frequent
> intervals, and carefully bury the removed items, then over the life of
> the house you end up storing more carbon in the ground, which means
> there's less in the atmosphere.
>
> Another good strategy (which I know will generate a lot of indiganant
> hot air) is to use asa many plastic products as you can bear.
> (Personally I detest the stuff and don't use it for anything.) The
> reason is that plastic represents carbon fossil fuels that get turned
> into stuff, instead of being turned into transport fuel and burnt, and
> then re-buried. That is, the carbon comes out of the ground, then
> after a few years goes back into the ground, without having been
> turned into atmospheric CO2. Basically, its better for the oil-and-gas
> stream to be, as much as possible, diverted to solid objects that get
> re-buried. But, only use plastic things when you can't use wood. Using
> wood means a lower atmospheric CO2 level than using plastic does.
>
> Looking after people is a good idea, but, actually, the planet doesn't
> care if a few more people die from cancer because of poisonous
> materials, so its hard to rate low-toxicity materials as high as
> minimising climate change effects. Which brings us to another can of
> worms...what/who are we trying to be good sustainable citizens for -
> human beings, or other species? Humans are REALLY bad for
> bio-diversity, generally. (This is a question I put to my students.
> Often the answer I get isn't the same as the one I get from ordinary
> folk.)
>
> No. Don't adjust materials to what's locally available. Use what is
> going to give the best life-cycle performance for the house. Don't
> worry about transport distances - they're such a distant second as to
> be a total red-herring.
>
> Hope this helps.
>
> Andrew
>
> 2009/2/19 Graeme North <graeme at ecodesign.co.nz>:
>
>
> Graeme
> Graeme North Architects
> 49 Matthew Road
> RD1
> Warkworth
> tel/fax +64 (0)9 4259305
>
> graeme at ecodesign.co.nz
> www.ecodesign.co.nz
>
> Begin forwarded message:
>
> From: Tim Owen-Kennedy <timok33 at gmail.com>
> Date: 19 February 2009 12:12:08 PM
> To: "(private, with public archives) Global Straw Building Network"
> <GSBN at greenbuilder.com>
> Subject: Re: [GSBN] Embodied energy comparisons: SB vs Stick-built
> Reply-To: "(private, with public archives) Global Straw Building Network"
> <GSBN at greenbuilder.com>
> Hi All,
>
> I might be wrong but I'm reading the flurry of communication lately as a
> bit
> of a sign that we are all a bit slowed down work wise; economy or winter
> (for us northies) or both? but I must say I'm appreciating the quality.
> Anyway...
>
> I'm always a fan of the "it depends" answer and the recognition of the
> "flaws" in the questions (I've been averaging all the lengths of the string
> in the craft room and will have an answer for you by next lifetime), but as
> hard as it is to put out numbers that can be taken out of context later it
> seems like it would be nice to have data on the economic impacts, embodied
> energy, sequestered carbon and comparative thermal performance of four
> simple wall assemblies, maybe 12 ft long with the same 3ft x4ft window in
> each.  (Boy I sure love single sentence paragraphs, hope you all could
> follow the above).
>
> For us in California I would like to know: standard 2x6 title 24 (minimum
> energy performance compliant) wall, high performance 2x6 wall with best
> accepted thermal detailing, load bearing straw bale with floating window
> buck, and a post and beam straw bale with the window mounted to full height
> 2x framing.
>
> As I write this I'm swimming in the feeling of the futility of this
> exercise
> but my assumption is that we'll see that the conventional wall has far less
> economic (distilled net energy from previous and potentially ecologically
> disastrous efforts) and embodied energy. The added costs of the roof and
> foundation for the thickness of the bale wall and the extra cost in
> detailing the bale wall will be really significant economic and embodied
> energy "costs". And that it might not payback easily in the thermal
> performance unless the project is designed to last much longer than it's
> mortgage, factoring in the carbon sequestration could really tip the
> argument. My thinking would be to get numbers attached to the value of
> durable natural energy efficient design.
>
> Therefore Durability has always been high on my top ten list of ecological
> design priorities which go something like:
> 1. Build as small as you can for the activities you want to house.
> 2. Invest the savings from building smaller in quality and durability.
> 3. Make all of it as personally beautiful, inspiring, and soothing to live
> in as your understanding allows; so that the building will be loved and
> cared for as it evolves.
> 4. Use materials that are as close to how they occur in nature as can make
> them durably beautiful.
> 5. Organize the materials to serve the activities and health of the
> occupants as passively as possible.
> 6. Adjust materials use in proportion to their availability in your area.
> 7. Maximize the value to the occupants of materials that are scarce and/or
> require lots of manufacturing or transportation.
> 8. Design and build with the evolution, recycling, and decomposition of the
> building in mind.
> 9. Review the Design so that the costs/impacts can be recuperated and
> ideally overcome by the benefits.
> 10. Maximize the Labor vs. materials ratio in the project - investing the
> most in local economies (high economic multiplier) and minimizes the risks
> of unintended consequences in the manufacturing, and make good use of the
> most enjoyably renewable resource on the planet, people.
>
> This is my attempt to frame the statements non technically toward what to
> do
> instead of what not to do; and to hopefully guide us to doing the best we
> can with what we know now. (My greatest design question still is since the
> bulk of the negative impacts of our efforts seem to come from unintended
> consequences - How do we design for what we don't yet know - biomimicry has
> been the best answer that's come so far).
>
> But it sure would be great to be able to quantify some of these concepts
> and
> adjust the priorities accordingly. It's just not something I'm capable of
> or
> I probably would have tried it by now. I would love to have any input on
> these that you are willing to share. Especially with regards to how best to
> factor in the Carbon
>
> I think the Skilled John's list is great and I would group all of them in
> under different priorities above. The issue always seems to me to be once
> you've answered each question as to what degree (relative to what standard)
> it is more yes or no, how do you compare it's relative value to the other
> answers.
>
> I love Derek's question of highest value and I've tried to address that
> with
> items 1,2,3,7 & 9 but think it could be worked in more explicitly.
>
> Well, sorry so long. I hope this is as valuable for some of you as it is
> for
> me, thanks for all your input on the refinement of "what we know now."
>
> Tim "caring and trying" O-K
>
> On Tue, Feb 17, 2009 at 8:26 AM, Joyce Coppinger <jc10508 at alltel.net>
> wrote:
>
>
> Count me as in favor of adding Andrew.
>
> Joyce
>
>
> on 2/16/09 4:00 PM, David Eisenberg at strawnet at aol.com wrote:
>
> Good idea!
>
> David
>
>
> -----Original Message-----
> From: Graeme North <graeme at ecodesign.co.nz>
> To: (private, with public archives) Global Straw Building Network
> <GSBN at greenbuilder.com>
> Cc: Andrew Alcorn <jandrew.alcorn at gmail.com>
> Sent: Mon, 16 Feb 2009 2:53 pm
> Subject: Re: [GSBN] Embodied energy comparisons: SB vs Stick-built
>
> Dear all
>
> I suggest that Andrew Alcorn be added to this list - he has been involved
> in earth and strawbale building research and design for many years and is
> one of the few researchers I know of who is delving deeply into this
> embodied and related  energy stuff in buildings
>
> In addition it will save me forwarding on loads of emails to him, and his
> replies to you
>
>
> cheers
>
>
>
> Graeme
> Graeme North Architects
> 49 Matthew Road
> RD1
> Warkworth
> tel/fax +64 (0)9 4259305
>
> graeme at ecodesign.co.nz
> www.ecodesign.co.nz <http://www.ecodesign.co.nz>
>
>
>
> On 17/02/2009, at 8:39 AM, Derek Roff wrote:
>
> How about a more abstract one:
>
> Is this the best use of this material?
> Are we diverting/consuming a material from some other more important use?
>
> This is sort of the flip side of recycling- removing things from the
> market that have other uses.  The poster child for this kind of dilemma is
> crude oil.  Oil pundits like to say it has a million different uses, from
> pharmaceuticals to fertilizers to building materials.  Instead, we burn 99%
> of it, getting the lowest possible use from an amazing material.
>
> Right now, I look on ethanol this way.  To produce a marginal (perhaps
> negative) energy source, we have impacted food supply and general wealth
> and
> health in Mexico among other places.
>
> I don't have an example in mind for this kind of misuse of a material as
> it relates to the building industry.  Perhaps others can suggest one.
>
> Derelict
>
>
> --On Monday, February 16, 2009 11:01 AM -0800 John Swearingen
> <jswearingen at skillful-means.com> wrote:
>
>
>
> Ok, since we've decided that embodied energy is of less or equal
> significance as life-cycle energy use, I would suggest that any
> materials or forms of construction be evaluated on at least these
> areas:
>
>
>   ? Does the material contribute structurally
>   ? Does the material contribute thermally (insulation)
>   ? Does the material provide thermal storage (mass)
>   ? Does the material provide fire safety
>   ? Does the material contribute to the local economy
>   ? What are the manufacturing environmental costs
>   ? What are the transportation and wastage environmental costs
>   ? Is the material a by-product, waste-product, or recycled
>   ? Is the material bio-degradable, recyclable or land-fill
>   ? Is the material toxic in manufacture, use or disposal
>   ? What is the expected life-span of the system (resistance to
> environmental damage)
> Feel free to add.
>
> John
>
>
>
>
> Derek Roff
> Language Learning Center
> Ortega Hall 129, MSC03-2100
> University of New Mexico
> Albuquerque, NM 87131-0001
> 505/277-7368, fax 505/277-3885
> Internet: derek at unm.edu
>
> _______________________________________________
> GSBN mailing list
> GSBN at greenbuilder.com
> http://greenbuilder.com/mailman/listinfo/GSBN
>
>
> =
>
> _______________________________________________
>
> GSBN mailing list
>
> GSBN at greenbuilder.com
>
> http://greenbuilder.com/mailman/listinfo/GSBN
>
>
>
> ________________________________
> A Good Credit Score is 700 or Above.  See yours in just 2 easy steps!
> <
> http://pr.atwola.com/promoclk/100126575x1218822736x1201267884/aol?redir=http://www.freecreditreport.com/pm/default.aspx?sc=668072%26hmpgID=62%26bcd=febemailfooterNO62
> >
>
> ________________________________
> _______________________________________________
> GSBN mailing list
> GSBN at greenbuilder.com
> http://greenbuilder.com/mailman/listinfo/GSBN
>
>
> _______________________________________________
> GSBN mailing list
> GSBN at greenbuilder.com
> http://greenbuilder.com/mailman/listinfo/GSBN
>
>
> _______________________________________________
> GSBN mailing list
> GSBN at greenbuilder.com
> http://greenbuilder.com/mailman/listinfo/GSBN
>
>
> _______________________________________________
> GSBN mailing list
> GSBN at greenbuilder.com
> http://greenbuilder.com/mailman/listinfo/GSBN
>
>
>
> _______________________________________________
> GSBN mailing list
> GSBN at greenbuilder.com
> http://greenbuilder.com/mailman/listinfo/GSBN
>
>

-- 
John Swearingen

Skillful Means
www.skillful-means.com
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.sustainablesources.com/pipermail/gsbn/attachments/20090220/d94a08fb/attachment.htm>