ENG/PHY160 May 10, 2011

1. ENG/PHY160 May 10, 2011 http://sexualsoul.tumblr.com/post/5436707155 I Carbon Sequestration II Conservation

2. ``First law of Economics:’’ TANSTAAFL There Ain’t No Such Thing As A Free Lunch The equivalent for economists of the Second Law of thermodynamics—always a cost no matter what. We will examine the costs and not present ``green technologies’’ as panaceas, but as subjects to study and consider for implementation.

3. Carbon Dioxide Sequestration • Capture the CO2 from production • Do one of the following: • Bury it in the ground • Bury it in the deep ocean • Induce increased uptake by biological sources

4. Generic cost estimates – common to all sequestration(based upon S. Holloway, Annu. Rev. Energy Environ. 2001, vol. 26, pp. 145-166) • Pretty hopeless to capture except at stationary sources (What are those?) • Have to capture carbon dioxide before it hits the flue – • cost is $18-72/tonne CO2-for a 500MW plant producing • 4.3 x 106 tonnes that gives added cost of 2-8 cents/kW-hr • Will lose efficiency to do work needed for capture – around • 15% or so, about 1 cent/kW-hr • Have to pipeline the CO2 at about $8/tonne, or another • 1 cent/kW-hr • Right off the bat, independent of sequestration method: • 4-10 cents/kW-hr

5. Where can you put this stuff underground? Caverns or mines – Not leakproof, not enough volume. Geological storage Cave source: www.cs.ualberta.ca/~mkan/Photography/ Mine source: www.mexicohorse.com/Lluvia_de_oro.htm

6. Pore spaces • Inject into porous rock at high pressure • Gas will rise to permeability cap • Some will dissolve into water (carbonic acid)

7. Concerns with porous rock storage • How much volume is available? • Global: 300-10000 Gtonnes (Annual emissions rise: ~8 • Gtonnes/yr from power plants- can store equivalent of between • 40-1500 yrs of CO2 from power plants ) • Rise in reservoir pressure (earthquakes?) • Conflicts with mineral/oil/gas extraction • Pollution of potable water • Escape of CO2gradual (Mammoth Lakes) or catastrophic (Lake Nyos, Cameroon – 1986 – 1700-1800 killed) • (Sources: Lake Nyos-http://en.wikipedia.org/wiki/Image:Lake_nyos.jpg; Mammoth Lakes: http://virtualguidebooks.com/SouthCalif/EastOfTheSierra/MammothLakes/MammothLakes_FSTOC.html) Mammoth Lakes Area (Gradual leak) Lake Nyos, roiled after Limnic Eruption

8. Depleted Oil/Gas Fields • Volume available: ~120 Gtonnes CO2 (about 60 years of power plant emissions) • Can enhance recovery of oil/gas from existing wells • Principal safety issue: leakage

9. Coal Beds • Adsorb onto nanometer scale fractures in the coal. High affinity, and displaces potentially recoverable methane.

10. Some food for thought • Food choices can reflect conservation

11. Passive Solar (Village homes in Davis)

12. Design Principles • Very simple and elegant idea, works in temperate and dry climates well. • Winter: windows face sun, house absorbs and traps heat, thermal mass releases at night. • Summer: Cool at night, close windows in day. No direct sunlight in house due to pitch of roof. Thermal mass slowly absorbs heat.

13. Practicalities: need insulation to make it work well in winter (little heating) and summer (little cooling) • Figure of Merit: R values—conventional commercial insulation at right. • R = d/k, d = thickness of wall, k = thermal conductivity. R is a measure of thermal resistance—conventional units are ft2-oF-hour/BTU

14. More on the physics of R values A1,R1,d1 A2,R2,d2 A3,R3,d3 Heat loss = Si AiDT/Ri A5,R5,d5 A6,R6,d6 A4,R4,d4

15. Note on polyurethane foam • Issues in production (frequently uses CFCs or HCFCs to make foam) • Polymers can presumably be made sustainably from biomass sources • In contrasting with straw bales, there is much less processing and use of straw bales correspond to an intrinsic recycling process vs. new manufacture (suspect cost is less per comparable insulation value, but have not found numbers)

16. So, what is good about straw bale? • Intrinsic recycling process—use waste straw from agriculture for insulation. • Cheap!!!! • Great R values • Did I mention cheap?

17. Straw Bale Housing Straw Bale House Dining Room Mattawa WA Library • Ugly and hippy-dippy right? • Unsuited for moist climates, right? • Worthless for other than houses, right? Straw bale in British Columbia Real Goods Store, Hopland CA Interior of Santa Fe Straw Bale House

18. How to put it together-a straw bale wall

19. Putting one up in Iowa

20. Moisture? Keep it below about ~20% to keep out bugs (percolation!)

21. Materials? Can get away with less.

22. Are straw-bale buildings a fire hazard? The National Research Council of Canada tested plastered straw bales for fire safety and found them to perform better than conventional building materials. In fact, the plaster surface withstood temperatures of about 1,850� F for two hours before any cracks developed. According to the Canada Mortgage and Housing Corporation, "The straw-bales/mortar structure wall has proven to be exceptionally resistant to fire. The straw bales hold enough air to provide good insulation value, but because they are compacted firmly, they don't hold enough air to permit combustion." (Source: http://www.eere.energy.gov/buildings/info/components/envelope/framing/strawbale.html) Table 4. Life cycle cost estimate for conventional vs straw-bale houses Conventional(Construction)$82,500   (Finance)396,000(Energy)120,000   (Total)532,500(Savings)------Straw bale(Construction)$78,375   (Finance)376,000(Energy)60,000   (Total)451,675(Savings)83,875Straw Bale* (Construction)$40,000   (Finance)192,000(Energy)60,000   (Total)260,000(Savings)272,500*owner-built walls, finishing, roofingNotes: Life cycle = 100 years. Finance cost = construction cost minus down payment of twenty percent at an annual interest rate of six percent over the one hundred year life cycle (does not include closing costs when the house is sold). Energy = the average cost for heating and cooling a conventional home for this analysis to be $100 per month. Total = Amount of down payment plus energy and finance. Source: Working Group Reports, Plastered Straw Bale Conference, "Roots and Revival," Arthur Nebraska, September, 1993. Source: http://www.eere.energy.gov/buildings/info/components/envelope/framing/strawbale.html Additional benefits • Cost: 2/3-full cost of construction of traditional home (depends upon how much you use contractors) • Great for fire safety • Likely good for earthquake safety (see http://www.sfgate.com/cgi-bin/article.cgi?file=/chronicle/archive/2002/02/03/CM28488.DTL and http://www.harrisondocumentary.com/ )

23. What about ``Cob’’? From http://www.cobcottage.com/whatis What is Cob? Earth is probably still the world's commonest building material. The word cob comes from an old English root meaning a lump or rounded mass. Cob building uses hands and feet to form lumps of earth mixed with sand and straw, a sensory and aesthetic experience similar to sculpting with clay. Cob is easy to learn and inexpensive to build. Because there are no forms, ramming, cement or rectilinear bricks, cob lends itself to organic shapes: curved walls, arches and niches. Earth homes are cool in summer, warm in winter. Cob's resistance to rain and cold makes it ideally suited to cold climates like the Pacific Northwest, and to desert conditions. Cob has been used for millennia even in the harsh climates of coastal Britain, at the latitude of the Aleutians. Thousands of comfortable and picturesque cob homes in England have been continuously occupied for many centuries and now command very high market values. With recent rises in the price of lumber and increasing interest in natural and environmentally safe building practices, cob is enjoying a renaissance. This ancient technology doesn't contribute to deforestation, pollution or mining nor depend on manufactured materials or power tools. Earth is non-toxic and completely recyclable. In this age of environmental degradation, dwindling natural resources, and chemical toxins hidden in our homes, doesn't it make sense to return to nature's most abundant, cheap and healthy building material?

24. Pictures of Cob Cob House in New Zealand Cob house in Russia Shaping Cob by Hand Cob Mud Pit Dance

25. Conservation Future: White Light Diodes? • Energy efficiency of commercially available: 2-6% • Efficiency of prototypes: 9-15% • 60W Incandescent: 2% • Compact Fluorescent:7-9%

26. Some numbers here • At peak efficiency, a 15% efficient diode light implies  replace 60W incandescent by ~8-10 W diode (replace 60W incandescent by ~15-20 watt fluorescent) and get same lighting intensity. • Diodes (and fluorescents) are more durable. • Aesthetics are an issue (incandescents have black body spectrum more like sunlight; diodes and fluorescents don’t….).

27. Photo credits • Iowa straw bale house: http://www.greenhomesforsale.com/listing.php?id=17581 • Santa Fe straw bale: http://www.greenhomesforsale.com/listing.php?id=17612 • British Columbia Straw Bale: http://www.greenhomesforsale.com/listing.php?id=17731 • Arizona Straw Bale: http://www.greenhomesforsale.com/listing.php?id=17768 • Straw Bale Moisture vs Relative Humidity: http://www.greenhomesforsale.com/listing.php?id=17768 • WA Straw Bale Library: http://www.newsdata.com/enernet/conweb/graphics/mattawa.jpg • Straw vs Stick wood use: http://oikos.com/news/2002/straw_table.gif • Straw Wall Schematic: http://radio.weblogs.com/0119080/images/Gallery/straw4.gif • Santa Fe Straw Bale Interior and Straw Bale Map: http://www.spiritdove.com/sf_strawbale.htm • Straw Bale House dining room: http://www.nemmar.com/images/re-photos-182w/re-182w-0174.jpg • Cob House Image from Russia: http://www.1-sovetnik.com/Pictures/houses/Cob-houses/Page-1/cob-house-18-i.jpg • Cob House Image from New Zealand: http://www.peak.org/~deatech/cobcottage/pics/cb1-4-2.low.jpg • Cob pit dance: http://www.cobcottage.com/node/148 • Making cobs: http://www.cobcottage.com/node/143 • White light diode: http://www.eere.energy.gov/news/news_detail.cfm/news_id=9322 • Village Homes: http://www.lgc.org, www.rmi.org/sitepages/pid209.php • Passive solar design: http://www.eere.energy.gov/de/images/illust_passive_solar_d1.gif • Straw bale R: http://solstice.crest.org/efficiency/straw_insulation/results.html • Commercial R: http://www.iowacoolers.com • Polyurethane schematics: http://www.pslc.ws/macrog/uresyn.htm