In accordance with ANSI and IEEE standards, medium voltage is defined as ranging between 600V and 69 kV. This range effectively encompasses most manufacturing industries. However, when manufacturing units utilize renewable energy sources, a challenge arises because most relevant Ecoinvent data points pertain to high voltage, causing discrepancies.
Solution: Addressing the Voltage Discrepancy
There are two primary solutions to this issue:
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Incorporate Electricity Transformation Data: Add the data point “Electricity transformation from high to medium voltage” in addition to the high voltage data point. This adjustment accounts for the voltage conversion process.
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Adjust for Transmission and Distribution Losses: Instead of adding the transformation data point, identify a reference for transmission and distribution losses during the data collection period. Then, scale up the total electricity consumption to account for these losses. The loss should be specific to the region where the manufacturing unit operates, with sources cited for accuracy. One potential source is the 2nd CEER Report on Power Losses. CEER Report on Power Losses.
Example:
Consider a wood sawmill in Austria that exclusively uses renewable electricity, consuming 1 kWh per declared unit. According to the referenced CEER report, the total losses in 2018 were approximately 2.9%. To account for these losses, you would adjust the emissions calculation by adding 2.9% to the renewable electricity data points (such as biogas, wind, hydro) in A3. This means changing the amount of used electricity from 1 kWh to 1.029 kWh. This adjustment includes both transformation and transmission losses of electricity.