How to calculate the CO2 emissions of an industrial machine
written June 06 2024
Determining the CO2 emissions of an industrial machine requires a series of steps and measurements. Here is a general process that can be followed:
1. Identifying sources of emission
- Fuel combustion: if the machinery uses fossil fuels, such as natural gas, diesel or coal.
- Power consumption: if the machinery is electric-powered, emissions can be attributed to the production of electricity, which often involves the combustion of fossil fuels.
- Chemical processes: some machinery may emit CO2 directly through chemical processes, such as cement or steel production.
2. Data gathering
- Fuel consumption: quantity of fuel used in a given period of time (litres, kg, m³).
- Power consumption: amount of electrical energy consumed (kWh).
- Production of CO2 from chemical processes: Quantity of processed chemical or product.
3. Calculating fuel combustion emissions
Use the specific emission factors for each fuel type. The emission factors indicate the amount of CO2 emitted per unit of fuel burned. For example, for natural gas, the emission factor can be expressed in kg CO2/m³.
\[ \text{CO2 emissions} = \text{Fuel consumption} \times \text{Output factor} \]
4. Calculating electricity consumption emissions
Determine emissions based on the energy mix of the local electricity grid. This mix can vary greatly by region and country.
\[ \text{CO2 emissions} = \text{Power consumption (kWh)} \times \text{Grid emission factor} \]
The emission factor of the grid can be obtained from local energy authorities or environmental agencies.
5. Calculating the emissions from chemical processes
Determine emissions based on the specific chemical reactions taking place in the machinery.
\[ \text{CO2 emissions} = \text{Product quantity} \times \text{Process output factor} \]
6. Sum of the emissions
Sum the emissions from the different sources to get the total CO2 emissions of the machinery.
7. Verification and constant monitoring
- Periodic check: ensure that calculations are accurate and up-to-date with any changes in consumption data or emission factors.
- Constant monitoring: implement monitoring systems to track the consumption of fuel, electricity and other sources in real time.
Practical example
Let's suppose an industrial machine uses 1000 litres of diesel and 5000 kWh of electricity in a month. If the emission factor of the diesel is 2.68 kg CO2/litre and the emission factor of the electricity grid is 0.5 kg CO2/kWh, the calculation will be:
\[ \text{CO2 emissions from diesel fuel} = 1000 \, \text{litres} \times 2.68 \, \text{kg CO2/litre} = 2680 \, \text{kg CO2} \]
\[ \text{CO2 emissions from electricity} = 5000 \, \text{kWh} \times 0.5 \, \text{kg CO2/kWh} = 2500 \, \text{kg CO2} \]
\[ \text{Total CO2 emissions} = 2680 \, \text{kg CO2} + 2500 \, \text{kg CO2} = 5180 \, \text{kg CO2} \]
By following these steps, it is possible to accurately determine the CO2 emissions of an industrial machine and take the necessary measures to reduce them.
Obtaining the emission factor from the electricity bill is not directly possible as electricity bills generally do not provide this specific figure. However, you can follow these steps to estimate the emission factor using other sources of information:
1. Consult the energy provider
Some electricity suppliers provide information on the energy mix used to produce the electricity they sell and the associated CO2 emissions. Contact your supplier and ask for this information. The energy mix is the percentage of energy produced from different sources (wind, solar, coal, natural gas, etc.).
2. Using national or regional Data
If your supplier does not provide this information, you can use national or regional data. In many countries, government agencies publish the average emission factor for electricity produced in the country or region. In Italy, for example, the GSE (Gestore dei Servizi Energetici) publishes the national energy mix and emission factors.
3. Calculating the Emission Factor
The emission factor can be calculated using the energy mix and the specific emission factors for each energy source. Here is a simplified example:
Steps for calculating the emission factor:
1. Getting the energy mix
Suppose the energy mix is as follows:
- 40% Natural gas
- 30% Carbon
- 20% Hydroelectric power
- 10% Wind power
2. Emission factors for each source (hypothetical values)
- Natural gas: 0.5 kg CO2/kWh
- Carbon: 0.9 kg CO2/kWh
- Hydroelectric power: 0 kg CO2/kWh
- Wind power: 0 kg CO2/kWh
3. Calculating the average emission factor
- Average emission factor = (40% * 0.5) + (30% * 0.9) + (20% * 0) + (10% * 0)
- Average emission factor = 0.2 + 0.27 = 0.47 kg CO2/kWh
4. Using the emission factor
Once you have the emission factor, you can use it to calculate the CO2 emissions associated with your electricity consumption. For example, if you consumed 1000 kWh in a month, your CO2 emissions would be:
\[ \text{CO2 emissions} = \text{Power consumption (kWh)} \times \text{Output factor (kg CO2/kWh)} \]
\[ \text{CO2 emissions} = 1000 \, \text{kWh} \times 0.47 \, \text{kg CO2/kWh} = 470 \, \text{kg CO2} \]
Helpful resources
- Environment agencies: many countries have agencies that publish reports on greenhouse gas emissions and average emission factors.
- Energy providers: can provide specific data for the energy sold.
Consulting these resources will enable you to obtain an accurate and up-to-date emission factor for your calculations.
The installation of a photovoltaic system can significantly reduce the overall emission factor associated with electricity consumption, as solar energy is a renewable source with virtually no CO2 emissions during its operation. Here is how you can consider the impact of the photovoltaic system on the emission factor:
1. Determining your personal energy mix
You have to calculate the amount of electricity you use from the grid and that produced by your photovoltaic system.
For example:
- Total power consumption: 1000 kWh
- Energy generated by the photovoltaic system: 400 kWh
- Energy taken from the grid: 600 kWh
2. Calculating associated emissions
Calculate the emissions associated with energy taken from the grid separately and consider that photovoltaic energy has zero emissions.
Grid emission factor:
Let us assume that the grid emission factor is 0.47 kg CO2/kWh (as calculated above).
Emissions from grid energy:
\( \text{Emissions from grid energy} = 600 \, \text{kWh} \times 0.47 \, \text{kg CO2/kWh} = 282 \, \text{kg CO2} \)
Emissioni da Energia Fotovoltaica:
\( \text{Emissions from photovoltaic energy} = 400 \, \text{kWh} \times 0 \, \text{kg CO2/kWh} = 0 \, \text{kg CO2} \)
3. Calculating total emissions
Sum the emissions from grid and photovoltaic energy to get the total emissions.
\( \text{Total emissions} = 282 \, \text{kg CO2} + 0 \, \text{kg CO2} = 282 \, \text{kg CO2} \)
4. Calculation of the modified average emission factor
Now, calculate the overall average emission factor taking into account the total energy used.
\( \text{Average emission factor} = \frac{\text{Total emissions}}{\text{Total consumption of electricity}} \)
\( \text{Average emission factor} = \frac{282 \, \text{kg CO2}}{1000 \, \text{kWh}} = 0.282 \, \text{kg CO2/kWh} \)
5. Applying the new emission factor
The new emission factor of 0.282 kg CO2/kWh can now be used to calculate CO2 emissions for total energy consumption that includes both energy from the grid and energy produced by your photovoltaic system.