Abstract Summary
A recently proposed approach for cooling underground tunnel substations using tunnel airflow is investigated across four different cities around the world, finding up to 21 kW of available cooling per pipe loop over 20 years of operation. The temperature of the air flowing in the tunnels is crucial to the amount of cooling that can be provided, while the farfield ground temperature is also impactful, to a lesser extent. The incorporated pipe length is varied, finding a logarithmic relationship to the amount of cooling energy provided, concluding that a leg length of 150-200 m is most resource efficient.
