1. 9.0 Energy Conservation & Efficiency Frank R. Leslie, B. S. E. E., M. S. Space Technology, LS IEEE 2/8/2009, Rev. 2.0.2 fleslie @fit.edu; (321) 674-7377 www.fit.edu/~fleslie Photo by EERE Crude oil, $71, 2/8/10 Retail Gasoline, $2.61 9 http://popup.lala.com/popup/432627077912420282

2. In Other News... Natural gas explosion kills 5 at Middletown CT Kleen Energy Station 2/10  Testing gas lines; 620MW; appears to be aero turbines with HRSG in two sections Iran’s Pres. Ahmadinejad orders enrichment of nuclear stockpile; Wants 20% U 235 (power 3.5%, weapons 93%) 2/10 Militants attack Nigerian oil pipelines to Bonny export terminal  Owned byRoyal Dutch Shell PLC 2/10 Obama’s Green Jobs effort competes against cheap labor in China (requires US subsidies to compete) “Feb. 4 (Bloomberg) -- President Barack Obama is spending $2.1 million to help Suntech Power Holdings Co. build a solar- panel plant in Arizona. It will hire 70 Americans to assemble components made by Suntech’s 11,000 Chinese workers.” http://www.bloomberg.com/apps/news?pid=20601072&sid=adIdrmtTtyw8Barack ObamaSuntech Power Holdings Co 100208 Ref.: Florida Today 2/8/10

3. 9 Overview of Conservation and Efficiency Avoiding waste of energy can compensate for diminishing supplies/sources, extending the time of depletion until other forms of energy may be developed and more widely employed Reducing energy requirements is effective, but implies “doing without” (not popular; hard to sell); lower usage rates may well be acceptable without much impact  Saving money for other things might sell the public Like to buy more electricity, or an iPod? Wasted energy, usually rejected as heat, can be captured and put to good use elsewhere through improved efficiency 070125

4. 9.0 About This Presentation 9.1 Conservation Issues 9.1.2 Depletion 9.1.3 Load Assessment 9.1.4 Reducing Loads 9.2.1 Source Efficiency 9.2.2 Transmission Efficiency 9.2.3 Distribution Efficiency 9.2.4 Load Efficiency 9.2.5 Transportation Efficiency 9.2.6 Impacts & Costs 5 Conclusion 060118

5. 9.1 Conservation Issues Unnecessary use of energy to over-cool or over-heat buildings is wasteful, especially if no one’s there Using cars and trucks with greater peak power than needed wastes liquid petroleum fuels that are needed elsewhere Matching the usage rate to the task effects brings about a balance that is effective in conserving energy  Some people normally drive small cars but rent a larger car for once-a-year long trips  Is a 10-mile-per-gallon, four-wheel-drive, SUV needed for a flat-road Florida trip to the grocery store?  Lowe’s and Home Depot rents trucks to customers to take large purchases home 100201

6. 9.1.1 Will “Conservation and Efficiency” save us from Fuel Depletion? Conservation implies not wasting energy as opposed to doing without  We need not “freeze to death in the dark” Efficiency means enhancing the productivity of energy production or use to gain as much usefulness as possible; effectiveness is doing the right thing!  Sizing a skillet to a stove burner more effectively cooks food without heating the room air so much  A combined-cycle power plant generates steam for a turbine with heat that would otherwise be wasted, raising the efficiency from ~33% up to ~67% Fuel depletion continues at a lesser rate with conservation & efficiency practices, but fuel will still “run out” (become very expensive) eventually 060126

7. 9.1.2 Value of Conservation: “Just a Virtue”? Conservation not only saves fuel for later use, but it saves money that may be used for other things; a low credit card balance means low interest payments Most choices are made on personal preferences based upon one’s beliefs and knowledge  Many (>51%) of the cars (light trucks) represent a psychological statement to the world (image)  On the other hand, is this choice morally “wrong”?  Europeans typically drive smaller cars and don’t feel deprived about it (so I’ve read) A current enviro-campaign to equate SUV drivers with supporters of terrorism alienates many people and is unproductive 080121

8. 9.1.2 Best Use of Limited Resources Choices are based upon individually perceived economics and results The definition of “best” varies with the user Petroleum, natural gas, and coal are valuable for many chemical compounds and products Aircraft need liquid fuel for distance coverage (high energy density on the plane) Time-of-use pricing reduces load energy demand peaks by charging customers more during peak load times than at low demand periods This use of the marketplace forces steers customer consumption habits towards saving money 100201

9. 9.1.2 Exponential Trend and Depletion Delay Energy use increases faster than population growth due to increased wants, desires, and even needs  Awareness of how others live may accelerate “wants” US CA Watts riots were said to be due to TV portrayal of huge TV set “homes filled with stuff”  Global television (CNN) spreads knowledge of others Population grows exponentially; war, disease, catastrophe, or famine, etc., may reduce that rate Shifting an exponential curve by conservation moves the end point for a given future year further away Changing energy usage can reduce or increase the slope of that curve indefinitely 100201

10. 9.1.2.1 Extending the Duration of Resources The best way to extend the resource life is to use less of the resource (cash for clunkers is the inverse)  Reuse Garage sales make products available to others rather than going to a landfill; “FreeCyclers” -  Free-cycling moves “used” things even faster Find a different use for it and avoid purchases  Recycle Paint is reblended for low-income housing dwellers Lead-acid batteries are ripped apart by a huge machine to recover the lead for new batteries Bottles and cans can be reprocessed with lower costs than starting with raw materials 050127

11. 9.1.3.1 Energy Load Assessment Various loads are in use for varying times, thus inventorying the energy consumption allows analysis of the principal energy uses A spreadsheet works well for this computation, and can be reused elsewhere (brain conservation!) List the load power in watts, time on in hours/day, and multiply to get the energy in watt-hours for each load Sum the energy, Wh per load to get total energy load Sort the rows to show the principal energy loads at the top of the worksheet for emphasis on what counts the most 090203

12. 9.1.3.2 Energy Load Assessment Site: Classroom 090203 LoadPower, WNo.Daily Use, hrEnergy, kWh/day Fluorescent Lamp 402*16 = 32810.24 PC & Monitor2001244.80 Projector600142.4 Laptop Computer 60120.12 Vacuum Cleaner 156010.0230.037 Peak Power156017.597 kWh/day Simultaneous Power 2460535.6 kWh/mo 6427 kWh/year Area = 25ft* 30ft = 750 ft 2 Energy Density = 23 Wh/day/ft 2 8766 hr/avg mo 730.5 hr/avg mo 30.4375 avg. day / avg mo

13. 9.1.3.3 Extrapolating Load Estimates 090203 BuildingFloorsApprox Ground Area, sq. ft Total Area sq. ft PSS3100x20060000 Olin Engrg.3100x20060000 Olin LS2100x20040000 Clemente2100x15030000 Tower560x10030000 Link3150x15067500 Library4150x15090000 Quad150x30015000 SUB280x8012800 Total405300 23 Wh/day/ft 2 x 405300 ft 2 = 9322 kWh/day x $0.07/day = $653/day; what’s left out?

14. 9.1.3.4 Using Waste Heat Utility plants can service nearby areas with metered hot water or steam, avoiding use of high quality electricity Geothermal energy in Iceland is collected to provide direct heat (hot water) to towns Iceland will develop hydrogen production from the abundant geothermal and hydro energy  Oh, but Iceland faces bankruptcy in 2009 Possibly an ammonia-cycle air conditioner running on waste engine heat could be used in cars  ROVAC in Rockledge worked on air-cooled compressors A home air conditioner could reject heat into a water-heater-intake- line heat-exchanger before reaching the condenser that rejects residual heat to outside air 090203

15. 9.1.4 Reducing Loads Variable speed motors on air heating/cooling systems reduce power requirements, matching energy used to the load Greater insulation in homes and refrigerators reduces heat gain/loss, and the HVAC compressor runs less New appliances incorporate “Energy Star” saving techniques  http://www.energystar.gov/ Compact Fluorescent Lamps (CFLs) use about ¼ to 1/3 the energy of incandescent lamps Motion detectors can shut off lights in an unoccupied room  My room was surveyed for this ~1/10/2007; no action yet Outside security lights come on when body heat is detected One could actually turn off an unneeded light by hand! 100201

16. 9.1.4 Lighting Conservation: Compact Fluorescent Lamps (CFL) vs. Incandescent In winter, waste heat from lamps warms a building and cuts other heating demand  Even body heat of the occupants heats the building ~100 watts per adult for shelter calculations  Some buildings have no fuel or electric heating source --- just body and lighting heat In summer, lamp heat increases A/C load Compact Fluorescent Lamps (CFLs) provide more light per watt than incandescent  More normal, white color temperatures are available  Prices have fallen to ~$1 to $3 per lamp  Outside CFL lamp fixtures are available; last longer  Downside: Harder to heat buildings or traffic lights with these (;-) 100201

17. 9.1.4.1 Building Energy Conservation The Florida Solar Energy Center (FSEC) in Cocoa studies building efficiency Note the relative balance of the heat leaks (right)  This makes insulation more difficult, since there isn’t just one type to insulate  Any one approach would help, perhaps ceilings first 070125 http://www.fsec.ucf.edu/bldg/fyh/ratings/images/HeatLoad.gif

18. 9.1.4.2 Building Infrared Heat Loss http://www.imaging1.com/images/energy-audit-home.jpg This infrared image shows the heat leak locations and the relative amount Work on the worst leaks first for the best payoff 100209

19. 9.1.4.2 Heat Loss & Gain Insulation is rated by resistance to heat flow, R, and conductance of heat, U, where U=1/R The R n for each of the materials are additive The heat flow is k A ΔT, where k is the heat conductivity, A is area, and ΔT is the temperature difference across the insulating barrier Units are ft 2 °F/(Btu/hr) or m 2 °C/W Some conductivity examples: air, 1.44 ft 2 °F/(Btu/hr)/inch; Fiberglass (batt), 3.16/in; pine wood, 1.28/in; wallboard, 1.0/in; brick, 0.11/in; glass, 7.2/in (Handbook of Chem. and Physics) 100211

20. 9.1.4.3 Heat Loss & Gain Example A wall has a layer of 4-inch brick outside, an air space of 0.5 inch, a batt (a pad) of 3-inch fiberglass, and ½-inch wallboard as the inside wall R total = (4”*0.11) + (0.5”*1.44) + (3”*3.16) + (0.5”*1.0) = 11.14 R-value total; the U conductance value is 1/R = 1/11.14 = 0.090 Btu/hr/ft 2 /°F or Btu/(hr-ft 2 -°F) Assume the outside temperature is 40°F and the inside temperature is 70°F, a difference is 30°F, and the wall area is 8 ft high by 10 ft long = 80 ft 2 The wall heat flow rate is 0.090Btu/hr/ft 2 /°F * 80ft 2 * 30°F = 216 Btu/hr The inside temperature can be kept stable by supplying 216 BTU/hr How would you decrease the loss rate? Fiberglass has the highest R, is inexpensive, and increases total R the most The best wall is a heavy concrete mass with insulation outside, covered to protect it from weather; stabilizes temperature changes 060126

21. 9.2 Energy Efficiency Efficiency is the amount of wanted energy converted divided by the total energy into the conversion process These efficiencies can be computed for the source or utility process, the transmission process, and the distribution process Typically, a coal-burning plant requires three times the chemical energy in for the electrical energy going out!  The extra “two times” is lost in heating the air This leads to notations like MW h for heat energy and MW e for electrical energy -- they’re 3:1 Increasing utility plant energy efficiency saves fossil fuel for later use 060126

22. 9.2.1 Source Efficiency A utility is rated by burn rate of amount of fuel/kWh Parasitic loads (lights, pumps, motors, blowers inside the plant) reduce the deliverable external power Combined-cycle power plants have a second stage of steam generation running on first-stage heat loss to drive an additional turbine Utility plants can also capture excess heat to sell steam or hot water through special meters 060126 http://www.bhpi.com.ph/Products/arrange-hrsg.gif Heat Recovery Steam Generator

23. 9.2.2 Transmission Efficiency Electrical transmission lines lose power in heat due to wire resistance; typical loss is designed to be ~3% to 5% Cost of increasing line conductance must not exceed value of power lost : Example: solid gold conductors one meter in diameter have low loss but are too expensive to use Higher voltages reduce current for a given power level  P loss = E 2 /R or I 2 *R, where P is power, E is voltage, R is resistance, and I is current More or longer insulators reduce leakage current from the lines to the grounded tower  The high voltage lines along the coast are pressure- sprayed with fresh water from a special insulated truck to remove salt from the insulators, reducing leakage 090203

24. 9.2.3 Distribution Efficiency Local distribution is from the ~275 kilovolt or so transmission line step-down transformer at a large substation to the homes and industry, etc. The high voltage in the following street distribution lines may be about 7200 V, thus a much smaller transformer is used to service 4 to 8 homes at 120/240V (overseas countries use different standards such as 240V, 50 Hz) The cost of higher efficiency is traded against the delivery of adequate power Service-limiting telemetry switches can reduce peak demands in hot or cold weather to share the service load; the customer gets a small credit for the interruption 090203

25. 9.2.4 Load Efficiency Improved appliance motor efficiency reduces demand Better lighting with CFLs  Lower power and longer life; less maintenance Use natural gas heat directly on site rather than burning gas to make electricity to get heat at distant location Use timers and occupancy sensors to reduce loads Air conditioners with larger (more) condenser fins transfer more Btu per watt of electrical power, resulting in a higher Seasonal Energy Efficiency Rating (SEER)  Better A/Cs are ~12 to 14 to 18 SEER  Takes more cooling fin area but saves money 070125

26. 9.2.5 Transportation Efficiency ~51% of US vehicles sold are SUVs (2008) Typical SUV gasoline mileage is ~18 mpg due to weight and peak engine power Average fleet mileage fell as more SUVs were chosen over sedans, and pickup trucks were chosen as cheaper Increasing mileage to 20 mpg would extend distance between fill-ups by 33%; use smaller gas tanks Perhaps maximum acceleration in g should be legislated to indirectly restrict engine power and fuel consumption  Spec: “Full-throttle-acceleration must be greater than 10 seconds for 0-to-60 mph” ??? Steel wheels on steel rails provide the most efficient land transportation, yet railroad passenger service has declined due to lower airfare and driving costs 100209

27. 9.2.6 Enhanced Efficiency Impacts & Costs Lighting areas can be better partitioned with more light switches in new construction; leave off lights in places  All of our classrooms should have switches to darken projection screens; I asked for E250 to have one Bright lighting is needed in work places in small spots rather than hallways or general room lighting Power plants should be incentivized by tax credits to seek higher efficiency Continuously variable ratio transmissions in vehicles improve engine efficiency Hybrid vehicles get strong electrical acceleration and thus allow for smaller internal combustion engines (ICE) Operating costs are reduced when efficiency is high 090203

28. 9.0 Conclusion Conservation by reducing loads or shortening duration of use will save money, reduce emission pollution, and extend the time that fossil fuels last Greater efficiency in generating, transmitting, and using energy will yield greater utility for cost Energy not used reduces the need for (puts off) utility plant construction and doesn’t cost $$$ Efficient use of fuels will save still more money and prolong their economical use While conservation and efficiency are valuable practices, they only delay the depletion of fossil fuels Eventually, rising costs will drive the change to alternative fuels --- start early to change over in time 090203

29. Olin Engineering Complex 4.7 kW Solar PV Roof Array 080116 Questions?

30. References: Books Anon. Handbook of Chemistry and Physics, 32nd ed. Boca Raton: CRC Press, Inc., 1950 Brower, Michael. Cool Energy. Cambridge MA: The MIT Press, 1992. 0-262-02349-0, TJ807.9.U6B76, 333.79’4’0973. Duffie, John and William A. Beckman. Solar Engineering of Thermal Processes. NY: John Wiley & Sons, Inc., 920 pp., 1991 Gipe, Paul. Wind Energy for Home & Business. White River Junction, VT: Chelsea Green Pub. Co., 1993. 0-930031-64-4, TJ820.G57, 621.4’5 Patel, Mukund R. Wind and Solar Power Systems. Boca Raton: CRC Press, 1999, 351 pp. ISBN 0-8493-1605-7, TK1541.P38 1999, 621.31’2136 Sørensen, Bent. Renewable Energy, Second Edition. San Diego: Academic Press, 2000, 911 pp. ISBN 0-12-656152-4. Revised 030120

31. References: Websites, etc. 070125 www.fsec.ucf.eduwww.fsec.ucf.edu Florida Solar Energy Center in Cocoa FL, Clearlake Road at BCC campus www.steab.org http://www.energy.gov/HQPress/releases01/maypr/chapter4.pdfhttp://www.energy.gov/HQPress/releases01/maypr/chapter4.pdf Energy efficiency http://www.energystar.gov/ ______________________________ awea-windnet@yahoogroups.com. Wind Energy elist awea-wind-home@yahoogroups.com. Wind energy home powersite elist geothermal.marin.org/ on geothermal energy mailto:energyresources@egroups.com rredc.nrel.gov/wind/pubs/atlas/maps/chap2/2-01m.html PNNL wind energy map of CONUS windenergyexperimenter@yahoogroups.com. Elist for wind energy experimenters www.dieoff.org. Site devoted to the decline of energy and effects upon population www.ferc.gov/ Federal Energy Regulatory Commission www.hawaii.gov/dbedt/ert/otec_hi.html#anchor349152 on OTEC systems telosnet.com/wind/20th.html www.google.com/search?q=%22renewable+energy+course%22 solstice.crest.org/ dataweb.usbr.gov/html/powerplant_selection.html

32. Slide stockpile follows! Older slides follow this one. Look at these if you have interest or time. It’s difficult to decide what to leave out of the lecture to save time!