2 1 M a y , 2 0 1 3 C o l i n M u r p h y M . S .

P h D C a n d i d a t e , I n s t i t u t e o f T r a n s p o r t a t i o n

S t u d i e s , U C D a v i s

Current Research on Air Pollutant Emissions from Bioenergy

1 . CURRENT STA TUS OF BIOENERGY IN CA

2 . A DVA NCED TECHNOLOGY

3 . MULTI-OUTPUT SYSTEMS

4 . MODELING COST EFFECTS A T NA TIONAL SCA LE

Overview

5.8 TWh of in-state biopower production 17% of in-state renewable power 2% of full California power mix SB 1122 adds FIT for 250 MW, SB 489, 594 improve net-metering

Current Biopower Capacity in California

* Includes: (a) LFG: 12 direct-use or CNG/LNG facilities; (b) WWTF: 8 heat or pipeline application; (c) AD: 12 Direct-use heat or fuel

Biopower Facilities

Facility Type Net (MW)

Facilities

Solid Fuel (forest, urban & ag) 574.6 27 LFG Projects (a) 371.3 79

Waste Water Treatment Facilities (b) 87.8 56

Farm AD (c) 3.8 11 Food Process/Urban AD (c) 0.7 3-5 Totals 1038 175

Solid Fuel (MSW) (mass burn facilities / organic fraction only) 63 3

Current Bioenergy Facilities

Current Solid Fuel Biomass Power

Like politics, all biomass is local. Feedstock and technology combinations reflect local conditions.

Many existing facilities idled or inoperative.

May be opportunities to repower or increase output through improved efficiency.

Mayhead G, Tittmann P. 2012. Outlook:

Uncertain future for California's biomass power plants. Calif Agr 66(1):6. DOI: 10.3733/ca.v066n01p6

Advanced Technology

Overview

No silver bullets for exhaust aftertreatment.

Focus generally on combustion technology, to reduce

pollutants entering gaseous phase

Lots of interest in integrating CCS or biofuel/bioproduct production

SCR Still the Standard

Orange County Sanitation District Using SCR on biogas from WWTP, achieving ~7-8 ppmv NOx,

some reliability problems. http://www.casaweb.org/documents/2013/03-ocsd_rothbart.pdf

Fresno Dept of Public Utilities Gas turbines burning 60/40 DG/NG, achieving ~3 ppmv NOx. http://www.casaweb.org/documents/2013/05-fresno_scr_turbine_hogg.pdf

Activated Carbon w/ Microwave Regen

CHA Corporation – SMUD Testing / Demo project on dairy digester biogas.

http://www.epa.gov/region9/organics/symposium/2010/5Lemes2010-PorsPres.pdf

Gasifier Project Examples

Phoenix Energy Authority to Construct (SJVAPCD)

Emission Limits NOx

(ppm) CO

(ppm) VOC (ppm)

PM10 (g/hp-hr)

SOx (g/hp-hr)

9 75 25 0.05 0.03

NOx (ppm)

CO (ppm)

VOC (ppm)

PM10 (gr/dscf)

SO2 (ppm)

Permit 98.8 2823 14.1 0.012 28.2 Source

Test 58 362 ND 0.0005 <0.4

CPC 50 kW at Dixon Ridge Farms (Winters, CA) [Yolo-Solano AQMD]

Emission Limits and Test Results

New 3-way Catalytic converter just prior to source test

Ankur derivative downdraft gasifier, gas scrubbing/filtering, recip. engine-generator (~500 kWe)

Downdraft gasifier, gas filtering, automotive V-8 engine-generator (~50 kWe)

UC Test Platform

Partial-Oxidation Gas Turbine

Partially oxidize NG at high pressure to generate excess H2, which allows ICE operation under ultra-lean conditions, to minimize NOx, <20ppm.

Demonstration project at San Bernadino WWTP. http://www.casaweb.org/documents/2013/07-san_bernardino_mwd_-_claus.pdf

Oxy-Fuel Combustion

Use gas or gasified biomass in pure-oxygen environement to produce highly-efficient combustion and minimal NOx formation.

CO2 can be recovered for EOR or CCS

Clean Energy Systems demonstration plants at Kimberlina and Placerita http://www.westcarb.org/pdfs_Lodi/Devanna.pdf

Multi-Output Systems

Biomass is Not Just Energy

Current research often emphasizes integrating systems to take advantage of local synergies CHP Nutrient Reovery Bio-Product Production

Biomass systems often struggle to be cost competitive on a purely energy basis, coproducts may be key to economic viability

Example – Dixon Ridge Farms

50 kW gasifier utilizing walnut shells (adding another 100kW)

50 kW gasifier displaces: 20% of facility electricity demand 15% of propane demand for heaters

Biochar is incorporated into soil Nutrient management Carbon sequestration N2O reduction?

Dixon Ridge

Dairy Digesters

Currently in limited deployment for energy purposes NOx permitting difficult Some reliability concerns Opportunities to better capture nutrients (N, P, K)

from effluent Reduce burden on surface water Displace fertilizer produced elsewhere Additional revenue

Digester Energy / Nutrient Recovery Concept

Modeling the Effects of Air Pollution Regulation on Biofuel

Industry Development

Geospatial Bioenergy Systems Model

Nationwide technoeconomic model Feedstock: Forest residue, MSW, corn stover, energy crops Biofuel demand: Based on county-level VMT Scope: Nation wide, county-by-county basis Biomass transport: Network model of road, rail and barge Conversion technology: Multiple biochemical and

thermochemical pathways

Produces spatial model of where conversion facilities locate and which feedstock sources they utilize

Produces cost curves for biofuel supply under various market conditions

Spatial Results

Supply Curves

Next Steps

Improve site selection heuristic Incorporate existing environmental policy Improve feedstock production model Competition with existing crops

Anecdotally – Air pollutant emission regulations

major obstacle to successfully developing a project

Cost Estimates

Cost factors for SCR and ESP systems on biochemical and thermochemical conversion facilities. All costs are in thousands of 2002 dollars

• Costs modeled on EPA guidance document for various technologies. • Costs are intended to be reasonable proxies for actual costs of achieving BACT or equivalent, rather than technological proscriptions.

• Typical capital cost for a biorefinery of this size: $400-500 million.

Effect of Air Quality Costs – High Ethanol Case

Effect of Air Quality Costs – Low Ethanol Case

Preliminary Results

About 1 cent/gge difference in average ethanol cost. Less than that in California Generally, very little response to the costs of air

quality Most facilities are outside of nonattainment zones Those that are, are uniquely positioned close to a market or

feedstock supply

Current model may be too location-agnostic Next generation – adding state-by-state cost factors

For more information:

California Biomass Collaborative Biomass.ucdavis.edu

UC Davis Policy Institute for Energy, Environment and the Economy

Policyinstitute.ucdavis.edu

Colin Murphy cwmurphy@ucdavis.edu Twitter: @Scianalysis

Rob Williams rbwilliams@ucdavis.edu

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CO NOx SO2 PM THC

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Chowchilla-Permit Chowchilla-Actual

El Nido-Permit El Nido-Actual

Madera-Permit Madera-Actual

Woodland-Permit Woodland-Actual

Ely,UK-Permit Ely,UK-Actual

Permitted and actual emissions for several solid fuel biomass plants.

Williams, R.B. (2005). Technology assessment for advanced biomass power generation - Final Report for SMUD ReGen program. University of California, Davis. CEC PIER Contract 500-00-034.