Science

These are all instructions and Explanations associated with this assignment.

During this tutorial you will:

1. Calculate the electricity demand for a household
2. Calculate the amount of fuel consumed to generate this electricity using non-renewable sources of energy
3. Calculate the greenhouse gas emissions for each fuel type and generation method

Instructions and explanations:

1. On the Energy Demand Sheet
   
   • fill in the number of units for each item you have
   • and the average number of hours of use per day.

   Keep in mind how your use may change through the year, and factor this into your daily use. Constantly-running units have typical hours of use already filled in (fridge, water heater, furnace). You may enter fractions of hours (ie. 15 minutes is 0.25 (one quarter) hour).

2. Calculate daily energy demand (in units of Watt-hours)
   
   • Multiply the number of units by the number of hours of use, then by the power demand.
   • At the bottom of the table add all of these together to calculate the total daily electricity consumption.
3. Complete the conversions at the bottom of the table. Transfer the individual annual electricity demand to the Fuel Consumption Worksheet
4. Non-renewable fuels are a form of potential energy. Each fuel type has its own energy density, or the amount of energy available to be released for a certain quantity of fuel. The energy densities of Fuels are given on this worksheet.

   (Notes: 1. m^3 = cubic metre, a measure of volume. 2. CANDU is the type of nuclear generating facility designed and used in Canada.)

5. Conversion of energy from one form to another always results in some energy being dissipated (or lost), usually as heat. The efficiency of this conversion of energy depends mostly on the technology employed. The table on this page shows the efficiency of generation as a proportion of the total potential energy. For example, if the efficiency of generation is 0.35, this means that 35% of the energy of the fuel is transformed into electricity (or 65% of the energy of the fuel is lost).
   
   • To adjust the energy density of the different fuels for the efficiency of electricity generation, multiply the energy density by the efficiency of generation.

     (Note: In combined cycle generating facilities, a gas turbine uses the hot gases released from burning natural gas to turn a turbine and generate electricity. The waste heat from the gas-turbine process is used to generate steam, which is then used to generate electricity.

6. To calculate the amount of fuel required to satisfy your annual household energy demand
   
   • divide your household energy demand (MJ) by the energy density adjusted for efficiency. (demand/density=fuel required)

Step 7. Calculating the GHG

1. • Use the GHG emissions worksheet 2016- Take the fuel required from each liquid or solid fuel type (e.g. Diesel (steam driven)) and multiply it by the emission factor. This will give you the emission in grams.- Then multiply this by the CO2 equivalent factor (CH4 has more warming potential than CO2).- (Co2 = 1, CH4 = 23, N20 = 317)- There are different values in the literature for these equivalent factors so if you used different one that is ok. I have included them in the version 2 of the GHG worksheet. This will give you the CO2 Eq in grams.- Add up the three CO2 Eq values for a total of CO2 Eq (g)- Divide this value by 1,000,000 to give you the value in tonnes.