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

Project Partners

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 Core Project Team

1.Optimize local thermophilic anaerobic microbial consortia 2.Implement a solar-biopower generation system 3.Evaluate the technical and economic performance 4.Establish an outreach program in Central America Project Objectives

Facts of solar energy From:  Advantages  Theoretical: 1.76 x 10 5 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. Central America 5

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

Agricultural residues available in Costa Rica 7 Residues Total amount (metric ton dry matter per year) Current treatment practices 2006Projection 2012 Cattle manure 1,530,0001,679,900 Only 20% of producers treat wastes, dried and composted Swine manure 95,000110, % for production of energy and rest in agriculture, fertilizer (45.5%) food animal (53.1%) or other uses (0.7%). Banana residues 158,000132,000 Not used as energy source,100% discarded or composted organic Coffee residues (pulp) 251,000 (husk) 25,000 (pulp) 262,000 (husk) 26,300 Pulp is used for composting, and husk is used for combustion Sugarcane bagasse 1,290,0001,518, % dried and used as combustion, 4.7% non energetic Pineapple residues 6,351,0008,452,000 Combusted and soil improvement  More than 600 MW electricity per year could be potentially generated from this amount of waste streams through anaerobic digestion technology.

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

9 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 Solar-biopower concept

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 a.The calculation of mass balance was based on the expected results that will be achieved by this project. b.A kg COD destroyed produces 350 L methane gas.

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

Construction site Solar Bio-Reactor Site Fabio Baudrit Experiment Station

16 – 2 m 2 flat-plate solar collector with support 22 m 3 anaerobic digester 50 m 3 gas bag 2 – 10 kW electric generators 4 – 144 m 2 wetland/sand filter cells Major system components Solar Bio-ReactorSand Filter / Wetland

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

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

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

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

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

Feedstock:  Beef manure (950+ kg/d)  Food waste  Chicken litter (20 kg/d) Temperature:  Currently 45 o C±2 o C  Target 50 o C±1 o C Biogas production: ≈ 20 m 3 /d Biogas quality: 60+% CH 4 Volatile solids destruction: 39% to 44% Solar-biopower system performance

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

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 Outcomes to date

Finalize microbial consortia papers Continue to operate pilot system until Sept 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 Next steps

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 : October 15 to 17 – Anaerobic Digester Operator Training (East Lansing, MI)  Highlights  System commissioning  Maintaining biological health  Safety  Operational troubleshooting  For information contact Other announcements

Questions? Dana M Kirk, Ph.D., P.E. Biosystems and Agricultural Engineering Anaerobic Digestion Research and Education Center E: P: