Emerado Public School: Energy Audit & Energy Conservation Alternatives Undergraduate Thesis Mechanical Engineering Kristin McKenzie March 15th, 2007

2 Purpose Conduct an energy audit of an existing school in Winkler Analyzing Manitoba Hydro data Modeling the building through a computer program Develop fossil fuel energy displacement strategy Incorporate renewable energy Implement in existing buildings

3 Procedure #1: Analyze Current Heating, Ventilation & Air Conditioning System (HVAC) #2: Computer Generated Building Model Electricity Consumption Natural Gas Consumption #3: Conduct Alternative Energy Analysis Electricity Consumption Natural Gas Consumption #4: Research Energy Efficient HVAC Alternatives Technical Analysis Cost Analysis

4 Procedure #5: Compare Electric & Natural Gas Consumption Results Computer Generated Actual Conservation Alternatives #6: Recommendation Reduce Costs Reduce Consumption Reduce Environmental Impact

Current Heating, Ventilation & Cooling Equipment Installed Heating Cooling Ventilation Heat Recovery Unit

6 Building Heating 2 Aerco Condensing Boilers –High Efficiency Maximum heat recovery from flue gases Heat contained in water vapor is released through condensing and re- directed into the boiler –Efficiency of approx. 95%-98% HHV –Low inlet water temperature <140F –1 MMBtu/hr

7 Building Cooling Evaporator Q out Compressor Hot refrigerant liquid Refrigerant liquid-vapor mixture Expand Compressed vapor Cold refrigerant Cold Water to School Hot Water from School CHILLER A Trane, 70 ton chiller is installed to provide building cooling Mechanical Work Q in

8 Building Ventilation Trane M-Series Climate Control AHU -Supply: 33,000 CFM -No pre-heat coil -Provides supply air for all school zones excluding the gym Trane M-Series Climate Control AHU -Supply: 5,000 CFM -No pre-heat coil -Provides supply air for only the gym

9 Exhausted Air (from Building) Heat Recovery Unit – Cycle #1 OUTSIDE Aluminum Cassettes Aluminum Cassettes Supply Air (to AHU) Damper

10 Exhausted Air (from Building) Supply Air (to AHU) Heat Recovery Unit – Cycle #2 OUTSIDE Heated Aluminum Cassettes Aluminum Cassettes Damper

Computer Building Modeling & Energy Simulation Procedure Results

12 eQUEST Procedure 1. Draft building floor plans in AutoCAD 2. Import floor plans into eQUEST 3. Create Building Shells 9 Shells required to model the Emerado School 4. Create building zones within all shells Multiple shells required within each shell to model the school Shell #1

13 eQUEST Procedure 5. Following procedure completed for all shells: Roof, wall, floor, window, door construction Building operation schedule Activity areas 6. Specify heating, ventilation and air conditioning equipment and parameters Shell #1: Main Level Shell #9: Upper Level Shell #2: Shell #3: Shell #4: Shell #5: Shell #6: Shell #7: Shell #8:

14 Simulation Results Heating Load Cooling Load (MBtu/hr) System # Main AHU System # Gym AHU System # Change Rooms TOTAL Actual Aerco Condensing Boiler Input: 1000 MBtu/hr * 2 = 2000 MBtu/hr eQUEST Calculated Required Input: 2049 MBtu/hr Actual Trane Chiller Input: 70 tons (840 MBtu/hr) eQUEST Calculated Required Input: 911 MBtu/hr

15 Simulation Results

Building Energy Conservation Alternatives Biomass BioFuel Boiler Absorption Chiller

17 Biomass Btu/lb Wheat Straw7528 Corn Cobs8070 Alfalfa6934 Sunflower Hulls 7474 Soybean Hulls 6660 Biomass –living or biological material that has recently been living, providing renewable energy Plant or animal matter Forest waste Municipal waste Food processing waste –Form of stored solar energy that is developed when sun is captured through the process of photosynthesis –Grown from: Hemp, corn, willow, sugarcane, switchgrass BioFuel Fuel derived from Biomass

18 Locally Produced BioFuel Local producer in Manitoba –Prairie BioEnergy Produces –Compressed biomass cubes made of a mixture of wood by products and flax –Energy Content 7900 Btu/lb –Density 33 pounds/ft² –Moisture Content Approx 5%-6%

19 Locally Produced BioFuel Product Handling –Product Displacement Conveyor Large screw auger –Storage hopper –Product must be kept dry Delivery System –Slow speed auger Combustion System –Ability to handle ash

20 Pelco Hot Water Boiler Locally distributed hot water boiler Solid fuel fired boiler Automatic feed auger Automatic ash removal system

21 Analysis Current Design New BioFuel Design Building Heating Requirements Approx 2,000,000 Btu/hr Aerco Condensing Boiler #1 1,000,000 Btu/hr Aerco Condensing Boiler #2 1,000,000 Btu/hr Pelco Hot Water Boiler 2,500,000 Btu/hr TOTAL2,000,000 Btu/hr 4,500,000 Btu/hr If required, condensing boilers will operate at part capacity Pelco HW boiler will run at near full capacity

22 Analysis 40 ton storage Prairie Fuel Cube Energy Content: –7900 Btu/lb Prairie Fuel Cube Moisture Content: –5%-6% of total mass BioFuel Boiler Input: –2.5 MMBtu/hour Required BioFuel: –2,500,000*6% + 2,000,000 = 2.6 MMBtu/hour Required biomass: –335.4 lb/hour –8,050 lb/day –Approx 4 tons/day

23 Cost Comparison NATURAL GAS –Blended Rate $0.3810/m³ –HHV.035GJ/m³ –Energy Input 2.5 MMBtu/hr = 2.6 GJ/hr –Required Volume NG m 3 /hr –Hourly Cost $29/hr BIOMASS –Cost $75/BDT –HHV 7.4GJ/m³ –Energy Input 2.5 MMBtu/hr = 2.6 GJ/hr –Required Biomass 0.14 tons/hr –Hourly Cost $11/hr

24 Cost Comparison

25 Absorption Chiller Evaporator Q in Compressor Hot refrigerant liquid Refrigerant liquid-vapor mixture Expand Compressed vapor Cold refrigerant Cold Water to School Hot Water from School ABSORPTION CHILLER Heat Input From Boiler **Trane 100 ton absorption chiller, approximately $155,000 Canadian Dollars

26 Is Biomass Feasible? Pelco Hot Water Boiler Prairie BioEnergy Displacement Equipment Absorption Chiller Potential Manitoba Hydro Chiller Incentives = Renewable energy Resource Eliminates fossil fuel Dependency Healthier for the Environment Reduced fuel costs

27 Conclusion Gained experience through studying and analyzing the current HVAC system installed Biomass provides an environmentally friendly, renewable resource, and readily available fuel is approx 1/3 of the cost of natural gas

28 Further Work Energy Conservation Alternative –BioFuel Boiler Cost Analysis –Solar Panels Technical Analysis Cost Analysis Design Recommendations

29 Acknowledgements Dr. E. Bibeau, P. Eng –Thesis Advisor Dr. P. Zanetel, P. Eng –Thesis Advisor Robert Bisson, P. Eng –Public Schools Finance Board –Mechanical Engineer George Marchildon, P.Eng –Public Schools Finance Board –Mechanical Engineer Terry Silcox –Manitoba Hydro Stephane Gauthier –Prairie BioEnergy Gerry Porter –Entropic Energy

Questions???