Biomass Energy: A Crash Course

1. Biomass Energy: A Crash Course Peter Flynn Poole Chair in Management for Engineers Dept. of Mechanical Engineering University of Alberta

2. Opening Thoughts • Society will likely have limits on its willingness to spend given that the problem is in the future. • What we get for the dollar spent varies widely. • The head needs to help the heart get the most environmental benefit per dollar spent. U of A Energy Club: February 2009

3. 1. Biomass is Carbon Neutral • The carbon it emits is taken up in regrowth of the plant. • If the biomass was not converted, it would rot and make CO2 anyway. • Hence, it displaces coal or oil. U of A Energy Club: February 2009

4. 2. Alberta Has Lots of It • Straw and forest harvest residues are annual crops. • Straw alone could supply the next 25% of Alberta’s total power usage. U of A Energy Club: February 2009

5. 2A. And May Have Much More U of A Energy Club: February 2009

6. 3. The Technology Exists Today: Power at Large Scale U of A Energy Club: February 2009

7. 3. The Technology Exists Today: Ethanol at Commercial Scale • Grain to ethanol is long established: • Whiskey • Corn to fuel grade ethanol • Barley and wheat in Alberta • Six commercial scale lignocellulosic ethanol plants announced in the US, including Iogen U of A Energy Club: February 2009

8. 3A. Whole Grain to Ethanol is a Poor Choice • Competition between food and fuel impacts the whole world. • Poor energy yield, high impact on soil and water quality. U of A Energy Club: February 2009

9. 3A. Lignocellulosic Ethanol • Lignocelluosic residues (straw/ stover and wood) are available waste products. • Purpose grown crops on marginal lands are also possible. U of A Energy Club: February 2009

10. 4. Research Isn’t the Correct Prime Focus • Research can be misused as a tool to postpone difficult choices. • Technologies exist today. • Alberta has a particular need for action. U of A Energy Club: February 2009

11. 5. Renewable Energy is not and never will be “Competitive” • We have used fossil fuels because they are cheaper. • Competitiveness isn’t the key question: we are paying more for an environmental gain. Someone must pay. The key objective is to buy the most greenhouse gas out of the atmosphere at the lowest extra cost. U of A Energy Club: February 2009

12. 6. Technologies are Not Equal.. • The cost per unit of energy output and per tonne of avoided CO2eq varies widely with technology and plant size. • Power from straw: ~$75 per MWh • Power from manure: ~$200 per MWh The minimum screen for any technology is “how much grant per tonne of CO2 avoided? U of A Energy Club: February 2009

13. And Can Be Studied in Detail • For each technology: • What is the appropriate size of plant? • How much CO2 equivalent is avoided? • Life cycle analysis need not be the complicated barrier it has morphed into. • How much extra does someone pay compared to a business as usual case. Minimizing extra $ per tonne of avoided emission is the right metric. U of A Energy Club: February 2009

14. 7. There is an Optimum Size; it is Large • Three elements to producing useful energy from biomass: • Get the biomass • Move it to site • Process it • Processing cost decreases with size, transport cost increases. U of A Energy Club: February 2009

15. Cost Per Unit Output Cost per Unit Output, e.g. $/MWh Can be positive (purchased) or negative (avoided cost) First Cost of Biomass Plant Size, e.g. MW U of A Energy Club: February 2009

16. Biomass Transportation by Truck • Costs include: • Loading and unloading: distance fixed. • Shipping: distance (scale) variable. • Typical values are $5 per tonne (distance fixed) and $0.09 per tonne km (one way) (distance variable). • Increases ~ with (scale)1/2. U of A Energy Club: February 2009

17. Distance Fixed vs. Distance Variable Costs Only DVC affects scale U of A Energy Club: February 2009

18. Cost Per Unit Output Cost per Unit Output, e.g. $/MWh Total delivered cost of biomass Transportation cost Field cost of biomass Plant Size, e.g. MW U of A Energy Club: February 2009

19. Other Modes are Available: • Pipeline (for liquid based processing only): high economy of scale, economic at sizes greater than 1 M Dry T/yr. • Rail: fixed cost of trans-shipment requires minimum economic shipping distance. U of A Energy Club: February 2009

20. Trans-Shipment: the Concept U of A Energy Club: February 2009

21. Trans-shipment: Alberta Based Straw Power Plant Minimum economic rail shipping distance exceeds draw area: rail is not economic. U of A Energy Club: February 2009

22. Biomass Processing: Use It • Economy of scale in capital equipment and operating costs, typical scale factors in the range of 0.6 to 0.8. • All evidence is that scale factor is valid up to very large processing sizes (>500 MW); road congestion limit is the prior constraint if delivery by truck. U of A Energy Club: February 2009

23. Scale factor for Manure AD Plants U of A Energy Club: February 2009

24. Data Consistency Varies Direct Combustion to power has been widely applied including very large scale plants. U of A Energy Club: February 2009

25. Hence Good Fit for Processing Cost Estimate: Direct Combustion U of A Energy Club: February 2009

26. Wide Scatter in Other Processes Fischer Tropsch estimates show wide scatter only partly due to configuration options U of A Energy Club: February 2009

27. Cost Per Unit Output Total plant processing cost Operating cost Cost per Unit Output, e.g. $/MWh Total delivered cost of biomass Capital cost Transportation cost Field cost of biomass Plant Size, e.g. MW U of A Energy Club: February 2009

28. Cost Per Unit Output Total unit output cost Total plant processing cost Operating cost Cost per Unit Output, e.g. $/MWh Total delivered cost of biomass Capital cost Transportation cost Field cost of biomass Plant Size, e.g. MW U of A Energy Club: February 2009

29. Power from Field Sourced Biomass in Alberta U of A Energy Club: February 2009

30. Optimum Size • Increases with increasing processing cost • Increases with increasing biomass availability • Is neutral to the field cost of biomass U of A Energy Club: February 2009

31. Optimum Size Depends on Biomass Gross Yield and Processing Cost U of A Energy Club: February 2009

32. The Optimum is “Flat” A 3% relaxation in the criterion of minimum cost drops plant size sharply. U of A Energy Club: February 2009

33. 50% of Optimum Size Has Minimal Impact, But the Cost Climbs Sharply Thereafter • Power from straw in Alberta: • $75 per MWh at optimum (330 MW net) • $77 per MWh at 50% of optimum • $100 per MWh at 25% of optimum • $125 per MWh at 10% of optimum • $145 per MWh at 5% of optimum U of A Energy Club: February 2009

34. Power from Field Sourced Biomass in Alberta • Straw to Power: >150 MW • FHR to Power: >100 MW • Lignocellulosic Ethanol: >3000 TPD • Power from Manure: county wide plant. U of A Energy Club: February 2009

35. 8.Life Cycle Analysis of Emissions • For most biomass plants the replacement of fossil fuel is the overwhelming contributor. • Processing related emissions tend to equalize. • Transport and refining are relatively small and estimates vary widely. U of A Energy Club: February 2009

36. LCA Values, CO2eq • Base load power vs. coal: 830 g/hWh, 1350 g/dry tonne of biomass. • Ethanol or diesel: 2000 – 2400 g/l, 600 g/dry tonne of biomass. • Power from manure (methane avoidance a factor): 900 g/kWh. U of A Energy Club: February 2009

37. 9. Put Cost and Avoided Emissions Together • How much extra does someone (the consumer or taxpayer) pay? • How much emission is avoided. • Pick the most cost effective process. U of A Energy Club: February 2009

38. Two key technology questions • For a given end form of energy, e.g. power or transportation fuel, what is the most efficient technology. (This will depend on the abundance of biomass, since low availability = higher delivered cost). • Between two end forms of energy, what should I pick. U of A Energy Club: February 2009

39. Gasification vs. Direct Combustion ~ Current power price in Alberta As straw availability drops, the required carbon credit increases faster for direct combustion than BIGCC. The crossover is beyond any point of real interest. U of A Energy Club: February 2009

40. Ethanol vs. FT Diesel Oil price range, 2008 to 2009 As straw availability drops, the required carbon credit increases faster for ethanol than FT diesel. U of A Energy Club: February 2009

41. Picking the End Energy Form U of A Energy Club: February 2009

42. Some Cautions • Some technologies are far better demonstrated than others, hence more confidence in cost. • All cost estimates rely on pre 2006 references, and hence miss the upswing in equipment and labor cost. The future of these costs is uncertain. U of A Energy Club: February 2009

43. 10. Policy Comes in Good and Bad Flavors • Jurisdictions around the world are wrestling with how to integrate a more expensive form of energy into an existing energy economy. • Some do it better than others. U of A Energy Club: February 2009

44. Bad Policy • “Man on the moon” targets obscure social costs. • Short term “up front” payments. • Higher payment to small scale projects. • Doing everything with every source (makes as much sense as making electricity from gasoline). U of A Energy Club: February 2009

45. Good Policy • Does not, for a global warming target, specify the end product of bioenergy. • Is long term • Allows competition between projects to meet a social goal at the lowest cost. • Identifies the cost per tonne of avoided CO2eq. U of A Energy Club: February 2009

46. For Biomass Energy to Grow: Drayton Valley, AB: 12 MW Alholmens, Finland: 240 MW U of A Energy Club: February 2009