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demonstrates this. A project and location specific review of
carbon emission reduction opportunities is required.
CONCLUSION
The reduced impact for CO2e emissions from electric
rather than conventional heating in a gold circuit can be
significant where grid connection to a very low carbon
grid is available. For grids with higher emission factors,
an assessment of the options from both an emissions and
cost perspective is required. Technical challenges around
shutdown and startup philosophy for these circuits require
additional consideration, however, practical approaches
have been defined to address risks. As momentum increases
with decarbonisation, electrification of more process heat
application is an area of opportunity in certain locations.
Table 2. Comparison of CO2e emissions impact of conventional and electric heating design for a range of grid scenarios
Design Case Energy source Qty/annum Carbon intensity tCO
2 e/ annum
Conventional heating Natural Gas 44,300 GJ/ annum 53.1 kgCO2e/GJ* 2350
Electric heating Grid power (BC Integrated
Grid)
27.4 GWh† (3400kw ×
8060hrs/ annum)
11.5 tCO2e/GWH 315
Electric heating Grid power (high Example
predominantly coal grid)
27.4 GWh 850 tCO2e/GWH 23,300
Electric heating Grid power (Example coal
plus renewables grid)
27.4 GWh 250 tCO2e/GWH 6850
*Note: Scope 1 -Natural gas emission factor does not include emissions associated with extraction and delivery of the gas.
† Note: This calculation is for scope 2 emissions for power predicted to be used by the electrified circuits highlighted green in
Figure 1 only (elution heating, electric kiln and electric smelting), and using published grid intensity data.
demonstrates this. A project and location specific review of
carbon emission reduction opportunities is required.
CONCLUSION
The reduced impact for CO2e emissions from electric
rather than conventional heating in a gold circuit can be
significant where grid connection to a very low carbon
grid is available. For grids with higher emission factors,
an assessment of the options from both an emissions and
cost perspective is required. Technical challenges around
shutdown and startup philosophy for these circuits require
additional consideration, however, practical approaches
have been defined to address risks. As momentum increases
with decarbonisation, electrification of more process heat
application is an area of opportunity in certain locations.
Table 2. Comparison of CO2e emissions impact of conventional and electric heating design for a range of grid scenarios
Design Case Energy source Qty/annum Carbon intensity tCO
2 e/ annum
Conventional heating Natural Gas 44,300 GJ/ annum 53.1 kgCO2e/GJ* 2350
Electric heating Grid power (BC Integrated
Grid)
27.4 GWh† (3400kw ×
8060hrs/ annum)
11.5 tCO2e/GWH 315
Electric heating Grid power (high Example
predominantly coal grid)
27.4 GWh 850 tCO2e/GWH 23,300
Electric heating Grid power (Example coal
plus renewables grid)
27.4 GWh 250 tCO2e/GWH 6850
*Note: Scope 1 -Natural gas emission factor does not include emissions associated with extraction and delivery of the gas.
† Note: This calculation is for scope 2 emissions for power predicted to be used by the electrified circuits highlighted green in
Figure 1 only (elution heating, electric kiln and electric smelting), and using published grid intensity data.