CRM Sample Questions 1. What are the CO 2 emissions for a facility in Miami that uses 1,000,000 kwh/year? 2. What are the CO 2 e emissions for the facility in question 1? 3. You install a solar PV panel on a carport that generates 1,000,000 kwh per year. If Renewable Energy Credits (RECs) are trading for $8 per REC, what are the RECs worth? (Assume you live in an area where you can do this, and ignore administrative/trading costs). a. $ 800 b. $ 8,000,000 c. $ 0 d. $ 8,000 4. In a Carbon Audit, which emissions should you always report? a. Scope III Emissions because they encompass the factors from Scopes I and II b. Scope I and Scope II Emissions c. Scope II and Scope III Emissions, because Scope I emissions can be estimated if you have the other data d. Scope I and Direct Emissions e. Scope I and Scope III Emissions (consistent with the WRI/WBCSD Protocol Initiative) 5. What are the CO 2 savings for switching a fleet from regular Diesel Fuel to Biodiesel (B20). The fleet currently consumes 50,000 gallons of diesel fuel per year 6. Are calculation-based estimation methods (which are more cost-effective than measurement-based methods) acceptable to most Reporting agencies? 7. Consider an office building in Arizona. Annually, if you purchase 1,000,000 kwh for electricity and 5,000 MMBTU of natural gas (for space heating), what are your Scope I CO 2 emissions? 8. Consider a process that requires 10,000 MMBtu/year and this energy is supplied by an old, oil-fired boiler (uses residual fuel oil #6) that is only 50% efficient. You retrofit to a natural gas fired boiler that is 80% efficient, what are the CO 2 emission savings? 9. Which of the following is the most cost-effective when aiming to offset your carbon footprint? a. Buy RECs from a windmill in Oklahoma at $10 per REC b. Buy CERs at $15/metric ton CO 2 e 10. Which has the greatest NPV assuming a 25 year planning horizon and MARR = 12%:
Install a $20,000 solar system that will last 25 years, and generate 38,000 kwh/year at $.10/kWh. Install a $25,000 Ground-Source Heat pump that will last 50 years and save $3,500/year. Ignore the value of RECs. Answers: 1. Lookup the CO 2 Emission Factor for Florida: CO 2 : 1,176.61 lbs/mwh (From EPA Emissions Tables or other relevant source) If we are consuming 1,000,000 kwh, then that is 1,000 MWh, and the CO 2 Emissions are = (1,000 MWh)(1,176.61 lbs/mwh) = 1,176,610 lbs of CO 2 Emissions, which we should convert to metric tonnes: = (1,176,610 lbs) (1 metric tonne/2,204.62 lbs) = 533.7 metric tonnes of CO 2 Emissions 2. Lookup the CH 4 and N 2 O Emission Factors for Florida: CH 4 : 0.03924 lbs/mwh (From EPA Emissions Tables or other relevant source) N 2 O: 0.01353 lbs/mwh (From EPA Emissions Tables or other relevant source) If we are consuming 1,000,000 kwh, then that is 1,000 MWh, and the CH 4 Emissions are = (1,000 MWh)(0.03924 lbs/mwh) = 39.24 lbs of CH 4 Emissions, which we should convert to metric tonnes: = (39.24 lbs) (1 metric tonne/2,204.62 lbs) = 0.0178 metric tonnes of CH 4 Emissions but now, we must multiply by the Global Warming Potential factor for CH 4, which is 21, thus: (21 mt of CO 2 e /metric tonne of CH 4 Emissions)( 0.0178 metric tonnes of CH 4 Emissions) = 0.37 metric tonnes of CO 2 e Emissions If we are consuming 1,000,000 kwh, then that is 1,000 MWh, and the N 2 O Emissions are = (1,000 MWh)(0. 0.01353 lbs/mwh) = 13.53 lbs of N 2 O Emissions, which we should convert to metric tonnes: = (13.53 lbs) (1 metric tonne/2,204.62 lbs) = 0.00613 metric tonnes of N 2 O Emissions
but now, we must multiply by the Global Warming Potential factor for N 2 O, which is 310, thus: (310 mt of CO 2 e/metric tonne of CH 4 Emissions)( 0.00613 metric tonnes of CH 4 Emissions) = 1.9 metric tonne of CO 2 e Emissions Now adding up the CO2 and the CO2e numbers provides the answer: = 533.7 metric tonnes of CO2 Emissions + 0.37 metric tonnes of CO2e Emissions (from Methane Emissions) + 1.9 metric tonnes of CO2e Emissions (from Nitrous Oxide Emissions) = 535.97 metric tonnes of CO 2 e Emissions 3. Answer = D. Because 1 REC = 1 MWh produced from a renewable source, the 1,000,000 kwh are only equivalent to 1,000 MWh and thus only 1,000 RECs. Thus the value is: =($8/REC)(1,000 RECs) =$8,000 4. Answer = B. Because Scope I and II Emissions are required by Kyoto and a minimum expectation if you are claiming to report a carbon footprint. 5. To determine the savings, we need to compare the emissions before and after the retrofit to B20, which by volume is 20% pure biogenic origin and 80% regular fossil fuel diesel. Lookup the CO 2 Emission Factor for Regular Diesel: CO 2 : 10.21 kg of CO 2 emissions per gallon of regular diesel fuel (From Emissions Tables) Before the retrofit, if we are consuming 50,000 gallons, then the CO 2 Emissions are = (50,000 gallons)(10.21 kg/gallon) = 510,500 kg of CO 2 Emissions, which we should convert to metric tonnes: = (510,500 kg of CO 2 Emissions) (1 metric tonne/1,000 kg) = 510.5 metric tonnes of CO 2 Emissions After the retrofit, we would only be consuming ~80% of the previous volume of fossilfuel diesel, and the remaining 20% would be biogenic content (which is reported separately from fossil fuel emissions). Therefore, the fossil-fuel diesel emissions would be: = (50,000 gallons)(10.21 kg/gallon) (.8) = 408,400 kg of CO 2 Emissions, which we should convert to metric tonnes: = (408,400 kg of CO 2 Emissions) (1 metric tonne/1,000 kg) = 408.4 metric tonnes of CO 2 Emissions The fossil fuel emission savings would be: 510.5 408.4 = 102.1 metric tonnes of CO 2 Emissions.
Note that you would report the biogenic CO 2 emissions separately, and they would be calculated as follows: Lookup the CO 2 Emission Factor for B100 fuel (100% pure biogenic material): CO 2 : 9.45 kg of CO 2 emissions per gallon of B100 fuel (From Emissions Tables) After the retrofit, 20% of the fuel volume will be pure biogenic (B100), so the biogenic CO 2 Emissions would be: = (50,000 gallons)(9.45 kg/gallon)(.2) = 94,500 kg of Biogenic CO 2 Emissions, which we should convert to metric tonnes: = (94,500 kg of Biogenic CO 2 Emissions) (1 metric tonne/1,000 kg) = 94.5 metric tonnes of Biogenic CO 2 Emissions 6. Answer = True 7. Scope I emissions originate from assets you own. Because an office building wouldn t own the electric generation station from which it buys kwh, the Scope I emissions would only involve the natural gas fuel that is used for space heating. Lookup the CO 2 Emission Factor for Natural Gas: CO 2 : 53.02 kg/mmbtu (From EPA Emissions Tables or other relevant source) If we are consuming 5,000 MMBtu then the CO 2 Emissions are = (5,000 MMBTU)( 53.02 kg/mmbtu) = 265,100 kg of CO 2 Emissions, which we should convert to metric tonnes: = (265,100 kg) (1 metric tonne/1,000 kg) = 265.1 metric tonnes of CO 2 Emissions (Scope I Emissions) 8. To determine the savings, we need to compare the emissions before and after the retrofit. Lookup the CO 2 Emission Factor for Residual Fuel Oil #6: CO 2 : 75.1 kg of CO 2 emissions per MMBtu (From Emissions Tables) Before the retrofit, if the boiler is only 50% efficient, then the fuel supplied to the boiler will be more than the 10,000 MMBtu needed for the process. Thus, the fuel input will be 10,000/.5 = 20,000 MMBtu. So, if we are consuming 20,000 MMBtu of fuel, the emissions would be: = (20,000 MMBTU)( 75.1 kg/mmbtu) = 1,502,000 kg of CO 2 Emissions, which we should convert to metric tonnes: = (1,502,000 kg) (1 metric tonne/1,000 kg) = 1,502 metric tonnes of CO 2 Emissions After the retrofit, we are using a different fuel, so we must lookup the CO 2 Emission Factor for Natural Gas: CO 2 : 53.02 kg/mmbtu (From EPA Emissions Tables or other relevant source)
After the retrofit, the new boiler is 80% efficient and the fuel input will be 10,000/.8 = 12,500 MMBtu. So, if we are consuming 12,500 MMBtu of fuel, the emissions would be: = (12,500 MMBTU)( 53.02 kg/mmbtu) = 662,750 kg of CO 2 Emissions, which we should convert to metric tonnes: = (662,750 kg) (1 metric tonne/1,000 kg) = 662.75 metric tonnes of CO 2 Emissions The CO 2 emission savings would be: = 1,502 662.75 = 839.25 metric tonnes of CO 2 Emissions. 9. To compare the economics, we need to get the options expressed in terms of $/mt of CO 2 e. To do that, we must convert the RECs into $/mt. Lookup the CO 2 Emission Factor for Oklahoma (for a quick comparison, we can ignore the impact of the Methane and Nitrous Oxide trace gases as they are a miniscule contribution to the CO 2 e emissions value): CO 2 : 1,599.02 lbs/mwh (From EPA Emissions Tables or other relevant source) Because 1 REC = 1 MWh produced from a renewable source, then that means that 1 MWh would not have been produced from the OK grid, thereby saving 1,599.02 lbs CO 2, which we can convert to metric tons by dividing by 2,204.62 lbs/mt, which yields 0.7253 metric tonnes. Thus, the value of the OK REC in terms of metric tonnes of CO 2 : =($10/REC)(1 RECs/0.7253 metric tonnes) =$13.787 per metric tonne of CO 2 Therefore, the Answer is A. Because on a cost per metric tonne basis, the RECs would be less expensive than buying the CERs. 10. To compare the economics, it is normal to think that we could use Annual Value because the projects have different lives. However, the problem states that the planning horizon is only 25 years, so in that case, we should use NPV. The savings from the solar system would be $3,800/year. PV of the Annual Savings from the Solar System: = $3,800/year (P/AIN Factor) = $3,800/year (7.8431) = $29,803 NPV of Solar System: = $29,803 - $20,000 = $ 9,803. PV of the Annual Savings from the Ground Source Heat Pump: = $3,500/year (P/AIN Factor)
= $3,500/year (7.8431) = $27,451 NPV of Ground Source Heat Pump: = $27,451 - $25,000 = $ 2,451 Therefore, the Solar System would have the highest NPV.