In this essay, I am going to attempt to put some numbers on some of the more relevant logistics and costs associated with transforming our transportation system to one that is automated and powered with wind and solar energy. This is a difficult topic to put into narrative but important to get a grasp of in order to have any gauge of the possibility of undertaking such a massive project. If anyone thinks they have better numbers for anything mentioned herein, I would be happy to hear about them since good information about much of this is difficult to find.
As I have mentioned previously, prefabrication will be one of the innovations that make this system better than our current roads. The question then becomes; how big can the pieces be? Current standards for one direction of travel on interstate highways call for two 12 foot lanes, 10 feet of paved right shoulder and 4 feet of paved left shoulder for a total of 38 feet. I am going to use 39 feet total for purposes of easier calculation. Other assumptions i will make are; 100 foot length, 3 ft. depth, and concrete materials. Concrete and reinforcing weighs a little over 2 tons per square yard but since there will be grooves for utilities in the sections we will call it two tons. All told this comes out to around 2,600 tons per section, well within the capacity of todays biggest cranes, some of which are capable of lifting over 14,000 tons. The larger problem will be transporting the sections. The largest weight I can find a source for having been transported on the highway is about half the 2600 tons cited above. Structural considerations will also come into play, so it may be that 50′ sections are more practical anyway. At any rate, the larger the sections of road, the less leveling and aligning that will be needed. This is important because every piece that needs aligned and leveled adds time to construction.
Materials for the above mentioned sections will be said to be 100′ in length for easy math. Numbers can be halved if 50′ lengths are required. If we say concrete is $100/cu. yd. (most contractors pay less but we are talking about the government here, besides it makes the math easy) and you have about 1300 cubic yards per section, each will cost $13,000. I figure it will be a wash between the lesser actual amount of concrete and cost for reinforcement materials (5% is usual extra cost). The current interstate system is a little under 50,000 miles so I will use that number to come up with $3.43 billion for materials for the bottom half of the system. The top half of the system that will enclose the roadway will not need to be as robust as the travel half and therefore should not be as expensive. However, any project of this scale will likely drive up prices at least to the point that we can more than double the $3.43 billion to about $7 billion. According to the Congressional Budget Office labor costs for road building varies from about $70,000 to a bit over $100,000 per mile. I think we can do much better with laying prefabricated sections but will take near the high end at $100,000 per mile to be conservative and to make easier math and come up with about $5 billion in labor costs. If we throw in another billion dollars for special equipment for handling sections of road, the total for the systems initial phase infrastructure comes to about $13 billion. Even if that figure goes up several times, it shows that the cost is well within the ability of our government to support and compares very favorably with the inadequate $50 billion a year of federal highway spending slated for the next couple of years.
Perhaps the largest expense will be vehicles to operate on the new system. To arrive at a reasonable figure I will assume that vehicles for the automated system will cost no more than cars do today and use $20,000 per vehicle as a ballpark estimate. Certain technology to be available in the new vehicles will likely offset much of the savings from economy of scale but it should be possible to keep costs nearer the low end of what new cars now cost. Depending on the specifics of the vehicles and system, it may be necessary to build as many as 250 million of them when the system is completed but for the part I am estimating at present will only consider 150 million, which I still consider to be a very conservative estimate. Now we are talking some real money at $3 trillion but let’s put it into perspective. Right now households in America already spend a trillion dollars every year on a very dangerous form of land transportation that not everyone is even able to use. The new system would travel up to four times the speed of current interstate roadways, so if the USDoT figure of 500 million hours per week in vehicles is close to correct, half a trillion dollars or more could be saved every year by cutting that time in half.
The current fastest computers in the world do as many calculations per second as if every human in the world sat at their computers 24/7 entering data for 46 years. The Cray Jaguar or IBM Roadrunner are a relative bargain at $100 million and either should be able to handle the information load necessary for a good control system. Even if 2 or 3 of them is required to have the redundancy required for such a system, the total costs for the controls should not exceed several billion dollars with hardware included. Just to put a number in it I will say $20 billion including labor, again being fairly conservative. This still leaves total cost for the system at just a little over $3 trillion or about two years of what our present system costs, which I believe is still a pretty good bargain.
In order to run the system off wind and solar energy, it will be necessary to incorporate some kind of grid into the network and it would be a good thing to make it robust enough to become the nationwide grid we need so badly to maximize efficiency of these power sources. In America, we use about 100 quadrillion BTU’s of energy per year, about a quarter of which is used for transportation. This translates to about 75 billion kilowatt hours or 800 megawatts of generating capacity. I am going to disregard solar for the purposes of this exercise and assume that windmills only generate 1/4 of their capacity so that 3,200 MW of generating capacity is required, an unreasonably high number but one that should give an idea of what the costs are. There are wind generators that can produce 6 MW of electricity but we will only consider 500 KW size since I have seen them listed for $50,000 (heck, they had 12 KW generators back in the 1880′s) and it makes for easy math once again. It would take 6400 such generators to supply the power stated above or cost about $320 million. Even if the cables and other equipment cost many times what the generators do, we are still talking a couple of billion dollars, not a large part of the system’s total cost. Just building the grid to what we need is estimated to cost many times this amount if done alone.
Adding networks like wi-fi, potable water, gas or anything else will increase cost but I would argue not by as much as any would cost to do alone. Many of the estimates above are ridiculously conservative but I believe the approximation of three trillion dollars is a fair figure for comparison purposes. One valid comparison I believe is that the federal government has spent half of that total for economic stimulus in just the past two years with very little concrete results to show for it. This is mainly meant to show that this project is well within our means to accomplish once we decide that operating dangerous 19th century design machines on roads that are technologically 2,000+ years old is not good enough for the 21st century.