Small-Scale Solar-Biopower Generation For Rural Central America

1. Small-Scale Solar-Biopower Generation For Rural Central America Project support from: US Department of State, Western Hemisphere Affairs Energy & Climate Partnership of the Americas (ECPA) Dana Kirk, Ph.D., P.E. Michigan State University Biosystems and Agricultural Engineering kirkdana@anr.msu.edu

2. Project Partners

3. Core Project Team • PI – Ajit Srivastava, MSU BAE • Co PI – Wei Liao, MSU BAE • Co PI – Dawn Reinhold, MSU BAE • Educational coordinator – Luke Reese, MSU BAE • Project manager – Dana Kirk, MSU BAE • Francisco Aguilar – UCR AE • Daniel Baudrit – UCR AE • Alberto Miranda – UCR AE • Lorena Lorio – UCR Micro • Lidieth Uribe – UCR Micro

4. Project Objectives • Optimize local thermophilic anaerobic microbial consortia • Implement a solar-biopower generation system • Evaluate the technical and economic performance • Establish an outreach program in Central America

5. Facts of solar energy Central America • Advantages • Theoretical: 1.76 x 105 TW striking Earth, Practical: 600 TW • It is the cleanest energy source on the Earth. • Solar energy reaching the earth is abundant. • Disadvantages • Sun does not shine consistently. • Solar energy is a diffuse source. • It is difficult to collect, covert, and store solar energy. From: http://www.global-greenhouse-warming.com/solar.html

6. Facts of Biogas Energy from Wastes • Advantages • A biological process • Reducing greenhouse gas emission • Enhancing nutrient management • Disadvantages • Low efficiency of organic matter degradation • Difficulty of power generation for small-medium operations Completely Stirred Tank Reactor (CSTR) Anaerobic Sequence Batch Reactor (ASBR) Plug-flow digester

7. Agricultural residues available in Costa Rica • More than 600 MW electricity per year could be potentially generated from this amount of waste streams through anaerobic digestion technology.

8. Solar-biopower concept Integrating wastes utilization with solar and biological technologies will create a novel self-sustainable clean energy generations system for small-medium scale operations Solar Energy Bioenergy Animal Manure Fertilizers Anaerobic Digestion Post- treatment Other Organic Wastes Reduced GHG Clean Water

9. Solar-biopower concept Benefits of system integration • Overcome the disadvantages of individual technologies • Unsteady energy flow for solar power generation • Low efficiency of mesophilic anaerobic digestion on degradation of organic matter • Higher energy requirement of thermophilic aerobic digestion • Provide sufficient and stable energy for small-medium sized rural community • Solar energy utilization • Improved efficiency of anaerobic digestion on degradation of organic matter • Biogas energy as chemical storage – steady energy flow

10. Mass balance Predicted mass balance for the integrated solar-bio system on 1,000 kg of mixed sludge and food wastes • Generating 66 kWh electricity per day • Producing 5 gasoline gallon equivalent (GGE) renewable fuel per day • The calculation of mass balance was based on the expected results that will be achieved by this project. • A kg COD destroyed produces 350 L methane gas.

11. Solar-biopower system Power unit Solar unit Bioreactor Post-treatment

12. Construction site Solar Bio-Reactor Site Fabio Baudrit Experiment Station

13. Major system components • 16 – 2 m2flat-plate solar collector with support • 22 m3 anaerobic digester • 50 m3 gas bag • 2 – 10 kW electric generators • 4 – 144 m2wetland/sand filter cells Solar Bio-Reactor Sand Filter / Wetland

14. Solar thermal system Solar collectors, hot water tank (white), & hot water storage (green)

15. Anaerobic digester Poly tank anaerobic digester Official ribbon (digester in background clad in tin) Field engineering

16. Feedstock & digestate handling Digestate solid-liquid separator Feedstock grinder, auger & mix tank (pump not shown)

17. Biogas storage Gas bag, foam interceptor, & scrubber Full gas bag, May 2, 2013 Biogas sampling

18. Sand filter & wetlands Sandfilter 1 Vertical wetland (sand filter 2) Surface wetland 2 Surface wetland 1

19. Solar-biopower system performance • Feedstock: • Beef manure (950+ kg/d) • Food waste • Chicken litter (20 kg/d) • Temperature: • Currently 45oC±2oC • Target 50oC±1oC • Biogas production: ≈20 m3/d • Biogas quality: 60+% CH4 • Volatile solids destruction: 39% to 44%

20. Water reclamation Organic waste Anaerobic digester Sand filter No. 1 Sand filter No. 2 Reclaimed water Original waste stream The effluent from solar-bioreactor The water from the 1st cell of post-treatment The water from the 2nd cell of post-treatment May 2013

21. Outcomes to date • Pilot system • Biogas production at 70% of goal • Biogas quality and solids destruction have achieved goals • Install biogas flow meter • Connect electrical generators to the experiment station power • Begin sand filter/wetland research • Bioenergy support lab at UCR – capable of carrying out BMP’s and other analysis • Utilization of local manufacturing – coffee equipment & solar panels • Study abroad “Ecological Engineering in the Tropics” completed in December of 2012

22. Next steps • Finalize microbial consortia papers • Continue to operate pilot system until Sept. 2014 • Operate portable unit at second location – wastewater or food processor • Complete economic and policy evaluation • 2013 study abroad planned for December • Expand bioenergy capabilities to address commercial needs

23. Other announcements • August 13, 2013 – MSU Waste to Resource Field Day • Highlights: • South Campus Anaerobic Digester (500 kW from 130 cows) • Research digester, compost facility, student organic farm, recycling center, power plant, ADREC • For more information go to :http://events.anr.msu.edu/adrec/ • October 15 to 17 – Anaerobic Digester Operator Training (East Lansing, MI) • Highlights • System commissioning • Maintaining biological health • Safety • Operational troubleshooting • For information contact kirkdana@anr.msu.edu

24. Questions? Dana M Kirk, Ph.D., P.E. Biosystems and Agricultural Engineering Anaerobic Digestion Research and Education Center E: kirkdana@anr.msu.edu P: 517.432.6530