Water in the context of Energy and Net Energy

Transcription

1 Water in the context of Energy and Net Energy GCEP/Stanford Net Energy Analysis Workshop Carey W. King

2 Water-Energy Nexus Did we just discover this idea? No Harte and El- Gassier, Science, 1978 Fossil fuels reduced the need for water for energy production Agriculture was 1 st energy sector Science, 1978 Carey W. King Net Energy Workshop April 31,

3 Water for Energy: Electricity Generation

4 Capacity Factor Cumulative Net Capacity (MW) U.S. hydropower exemplifies water constraining energy US Hydropower Performance and Capacity , , Capacity Factor 80, Hydro Capacity (MW) 60, , , EIA Annual Energy Review Carey W. King Net Energy Workshop April 31,

5 Different thermal power plant cooling technologies have different water needs, benefits, and impacts King, C.W., et al., Natural Resources Journal, 53 (1), 2013, Water consumption for power in U.S. (& Texas ) ~ 3-4% of total consumption Dr. Carey W. King 4/2/2015 Carey W. King Net Energy Workshop April 31,

6 Does anyone consider net energy in water policy? But they [state regulators] gave cities and power plants along the Brazos a pass, concluding that public health and safety overrode the farmers own water rights. (emphasis added) Carey W. King Net Energy Workshop April 31,

7 Can State of Texas take farmers water rights for electricity & green lawns? Travis Co. (Texas) court said TCEQ did not have the authority to exempt customers like cities and electricity generators from the water cuts based on how they used the water. Carey W. King Net Energy Workshop April 31,

8 Can State of Texas take farmers water rights for electricity & green lawns? Travis Co. (Texas) court said TCEQ did not have the authority to exempt customers like cities and electricity generators from the water cuts based on how they used the water. Carey W. King Net Energy Workshop April 31,

9 What amount of water and electricity are needed for public health and safety? Water Hospitals, municipal supplies (fire hydrants) Industrial facilities? Food production? Electricity Meet full peak summer power? Meet air-conditioning load + city services? Commercial and industrial power? Carey W. King Net Energy Workshop April 31,

10 Dissertation level economic analysis ERCOT Dispatch model with all power plants simulated for 1 year Charged power plants water fees up to $1000/ac-ft of consumption Conserves water at >240,000 $/Mgal (80,000 $/ac-ft) Kelly Sanders et al. (2014), Env. Sci. & Tech 48(12). Carey W. King Net Energy Workshop April 31,

11 Back of the envelope analysis Texas agriculture: 2,000 $/ac-ft (revenue/water) 2012 cash receipts $20 Billion/yr 1 10 M ac-ft for irrigation ERCOT electricity: 20,000-40,000 $/ac-ft (revenue/water) Wholesale prices ~ $/MWh; 325 TWh in 2012 $10 $16 Billion/yr 400, ,000 ac-ft/yr water consumption NOTE: Dry cooling incentivized at 1,000-2,000 $/ac-ft Dow Chemical (Freeport, TX): ~130,000 $/ac-ft (revenue/water) $18 Billion/yr (21% Dow s global production) 2 ~140,000 ac-ft/yr water consumption Tim Finley, Dow Chemical Company. Carey W. King Net Energy Workshop April 31,

12 Dry cooling systems do work: Increased cost increased water resiliency Australia, South Africa, and Western US examples Queensland, Australia: Air-cooled condenser on supercritical coal Kogan Creek ~ 45% power efficiency (LHV) South Africa: air-cooled condenser at Matimba Power Station South Africa (photo: courtesy of Eskom) NER decreases due to Lower efficiency Higher capital investment Carey W. King Net Energy Workshop April 31,

13 Dry cooling tends to be employed based on non-economic constraints Net energy likely not more informative Breakeven cost of designing for dry cooling 1,000-2,000 $/ac-ft (3-6 $/kgal) The price of water is rarely the deciding factor Water is present and available, or it isn t Water costs either < 3 $/kgal or > 6 $/kgal (infinite) No precedent for retrofitting to dry cooling Carey W. King Net Energy Workshop April 31,

14 Water for Energy: Transportation Fuels

15 Technological advances enable multiple future transportation fuels money.cnn.com odec.ca frontpagemag.com pixmac.com treehugger.com sulangaenergy.com Carey W. King theszencorpbuilding.com Net Energy Workshop April 31,

16 Water Consumption Intensity from Near Zero to > 100 gal H 2 O/mile King & Webber (2008). Env. Sci. & Tech. 42 (21), Carey W. King Net Energy Workshop April 31,

17 Water Consumption Intensity from Near Zero to > 100 gal H 2 O/mile King & Webber (2008). Env. Sci. & Tech. 42 (21), Carey W. King Net Energy Workshop April 31,

18 Even algal biofuels in a closed bioreactor Irrigated Not Irrigated Experimental Ideal production Corn ethanol (irrigated) Corn ethanol Algae biodiesel + methane Carey W. King Net Energy Workshop April 31, (not irrigated) Soy biodiesel

19 The world becomes more coupled every day we can call this the Water-X-Y-Z Nexus? Carey W. King Net Energy Workshop April 31,

20 The world becomes more coupled every day we can call this the Water-X-Y-Z Nexus? Carey W. King Net Energy Workshop April 31,

21 Just subtract water and exacerbate any existing conflict FRAC IT of my water. from my land. etc. anytime. anyplace. etc. Carey W. King Net Energy Workshop April 31,

22 Just subtract water and exacerbate any existing conflict FRAC IT not in a college town. anytime. anyplace. etc. Carey W. King Net Energy Workshop April 31,

23 Food = energy; Food + energy costs up since 2002 (U.S.) = Recession Water ~ $0 CO 2 = 0$ Water > $0 CO 2 > 0$ Carey W. King Net Energy Workshop April 31,

24 World energy expenditures + water for energy Water is largely in prices via the supply chain E.g. water for hydraulic fracturing, steam injection Externalities on biodiversity perhaps not included Cooling or hydropower reservoirs evaporating water and altering flows and temperatures Fish migration Water not flowing into bays Carey W. King Net Energy Workshop April 31,

25 World energy expenditures + water for energy Water is largely in prices via the supply chain E.g. water for hydraulic fracturing, steam injection Externalities on biodiversity perhaps not included Cooling or hydropower reservoirs evaporating water and altering flows and temperatures Fish migration Water not flowing into bays Carey W. King Net Energy Workshop April 31,

26 Carey W. King Assistant Director, Energy Institute Research Associate, Jackson School of Geosciences Lecturer, McCombs School of Business careyking.com Available from ASME Press