The boring company includes the idea of ~140MPH electric sleds that carry cars. This is part of their goal for 1/10th the price. It may or may not be implemented long term, but it is a novel concept and they are actually digging right now to gain expertise.
I would call it similar to Space X before they started landing the rockets. Just making digging cheaper much like making rockets cheaper is a basis for a profitable company. A long term goal of 1/10th the price really would be game changing.
PS: Picture even a one way toll road that goes 20 miles under I-66 into DC they could easily charge 10$/ trip an get 100,000+ riders each way per day. So, the real question is how much that tunnel costs. At 20 billion $ that's 20 billion * 6% ~= 1.2 billion per year vs 2 * 10 * 100,000 * 5 * 48 = 480 million so not a win. But, at 1/10th the price or 2 billion that's ~120 million per year break-even vs 480 million and highly profitable. How many places could a 5 mile segment be able to charge say 3 dollars and have 100,000 people per workday?
Consider this comparison: buses carrying 50 people each on I-66 going 60mph. Which is going to carry more people into DC, at what cost? Think of the station wagon filled with hard drives vs. gigabit internet.
Cars, unless going ungodly fast (140mph is not enough), are inefficient at throughput.
You can design a bus for these tunnels fairly easily. However, 140mph under a city vs 3 mph at street level and buses lose unless they have 47+ passengers but a 50 passenger bus costs 2-3 car slots easily so it's a wash.
PS: I-66 really does have 3mph traffic as it will take 30+ minutes to travel 10 miles. As in I was happy if that part was under 30 minutes, and not surprised if it took 40 minutes as the average was well over 30.
I would call it similar to Space X before they started landing the rockets. Just making digging cheaper much like making rockets cheaper is a basis for a profitable company. A long term goal of 1/10th the price really would be game changing.
PS: Picture even a one way toll road that goes 20 miles under I-66 into DC they could easily charge 10$/ trip an get 100,000+ riders each way per day. So, the real question is how much that tunnel costs. At 20 billion $ that's 20 billion * 6% ~= 1.2 billion per year vs 2 * 10 * 100,000 * 5 * 48 = 480 million so not a win. But, at 1/10th the price or 2 billion that's ~120 million per year break-even vs 480 million and highly profitable. How many places could a 5 mile segment be able to charge say 3 dollars and have 100,000 people per workday?