tunnel of love

A key insight of the new rigs for digging tunnels, geothermal heat exchangers and deep-sea oil-well-drilling robots is the dramatic cost reduction obtained by a smaller tunnel. If you imagine a tunnel that will only allow for EVs (vehicles or sleds), you don’t have to deal with the massive air-handling pipes to evacuate toxic diesel exhausts. At the limit, I wonder if CO2 scrubbers, as used in submarines and spacecraft, could locally purify like a scuba rebreather.

“The current standard for a one-lane tunnel is approximately 28 feet. By placing vehicles on a stabilized electric skate, the diameter can be reduced to less than 14 feet. Reducing the diameter in half reduces tunneling costs by 3-4 times.”
— Boring FAQ