( picture: borrowed from: Agent Bob) …
Well, then, what is a circular road? was a question that was asked , after the previous article. To answer, lets first analyze what happens when constructing a highway with current approach. Then somewhere in the world , a mountain is dismantled, like for cement production. Somewhere the soil is dig up for resources, like gravel, and the depth is left and fills with water, ending as lost land. Somewhere the land sinks, since fossil fuels are extracted, and the land soil above is collapsing ( like in Groningen in The Netherlands). In the mean time, the waste is dumped in China, and the climate warms by all the energy exhausted.
So that’s our reference and starting point for determining what a circular road should look like. If you want to avoid all these open ends in cycles, you have to find solutions that close those cycles. As before argued, circularity is not about a building or a road, but about resource cycles. The road is a temporary stock pile, within a constant flow in the system, slow or fast.
And this is only about the road. A road only exists since there is need for driving at that point. So the transport on top of the road is part of the impact of constructing a road as well. Its an integrated system, in a total circular approach. And transport is a lot of energy , which again causes earthquakes due to collapsing soil, as well as climate warming. Not to speak of the material resources that went into the vehicles, with more excavated mountains and sinks.
Which are by the way only impacts of the 1st order. There are also second and third order impacts, like the factories, the machinery etc.
So here we have our system we want to turn into a circular approach. The approach is similar with that of buildings of course: linear delaying of the flow of resources, and circular restoring for the part that exceeds natural flows. Both in the end can be compared with renewable energy as the common denominator, for which a time-space (land) relation can be developed. 
When discussing a circular road, the road is usually taken as a given fact, with the properties like size and such already fixed. From there in a reductionist way each element is analyzed and slightly improved. But there is more of course: its the systems function that should be analyzed, at all scale levels. Since what is the meaning of the road? Its going from A to B. If that is the only requirement, there is not so much at stake. That could be provided with a semi-hardend, or gravel road. Which makes a huge difference in impact. And yes, the transport is slowed down that way, but is there any law that states that there is a minimum speed of transportation required? The fact that that transport can be fast , does not imply it should be fast…. , or that fast should be facilitated…
The faster we want from A to B, the higher the impact. Which requires the roads to meet high standards, and the vehicles to be more heavy , which in turn requires more fuel, etc etc.
If we regard a system of say 1 km of highway, the highest reduction in impact can come from a speed reduction. Which leaves us with two options: either take the road as a given design, and improve bits an pieces here and there ( small steps in linear delaying) , or take a wider perspective and look at the optimal speed from a resource point of view. Its a balancing act: where is the optimum?
With 80 as the maximum speed, compared to 130, or more like in Germany, you can do with less wide lanes, and skip the emergency side lanes. Which adds up to at least 30 % resource reduction. Maybe even more, while avoiding fly overs to be constructed. While cars can be much lighter, with a much lower fuel consumption, even if the transport would or will be electric: See this article by Kris De Decker .
And all is related to time: If less resources needed, less time is needed to restore stocks. Let us take the example given by De Decker to illustrate this: He writes: “ at a speed of 80 kilometers an hour, a (electric) car over a distance of 1000 km, will use 187 kWh ( 12,5 hours times 15 kilowatt). When driving with 160 km/h, this becomes 750 kWh ( 6,25 hours times 120 kilowatts), 4 times more .
Which of course should be compared in terms of Solar panels generated energy, since we are, and want, a transition to renewable energy, especially for electric cars.
In the example the voyage with reduced speed takes 12,5 hour in stead of 6,25 , however generating the energy for this trip, takes 4 times as long compared to the 80 km/h trip: Suppose you have 1,5 m2 Solar panel at home, which provides 187,5 kWh per year. Which is sufficient for the 1000 km trip at 80 an hour. To provide the energy to make the trip at 160 an hour, you will have to wait 4 years before you have gathered enough kWh’s! That time is not available, at least we don’t want to wait 4 years, therefore we need 4 times as much solar panels installed, to stay in balance ( regarding energy) . Which of course requires more land use as well, 4 times as much. Which also requires 4 times more financial investments in the transition to renewable energy. ( even excluding he resource impacts for the panels ). Thats the difference between driving 80 and 160.
Now these are a few simple explorations, but what it shows is that there is a direct relation in space time between speed on one side and energy demand on the other side. ( and the same is true for the -4 times- more resources involved-for heavier cars road and more PV panels) , though I have not yet made the calculations).
In other words: you may want to choose higher speeds, but this backfires in terms of much more time needed for restoring resources, if only by the higher volume. And though I don’t think money is a good indicator, since a fantasy constructed unit, but in this case the relation between Time and money seems to be there: to gain six hours of travel time, requires 4 times more investments in energy generation and materials , for the same distance traveled.
Another aspect of the system ‘1 km highway’ , is that the impact s directly related to the amount of people per vehicle. The more individual the transport, the higher the impact. Which shows the relation with analyzing at different scale levels: if the speed is reduced, going from A to B , a bicycle may become an option : and the disadvantage of individual transport has been overcome. ( and its more healthy as well) . Or consider a scale step the other way: with mass public transport , like buses and trains.
Another element is that you could take into account in a systems analyses, the activities around and near the road: In a recent project analyzing impact reduction from a university building, one of the most effective solutions turned out to be the change to distant learning, No buildings needed, and hardly any displacements required ( of students and teachers to and from the building) . ( and in the Netherlands the open university, with distant learning programs, is among the highest rankings) . Which reduces the need for roads as well. These are all options that have a direct relation with the road, and should be studied to make a circular function possible; reduce volume speed and energy involved in resource cycles, until it fits into the natural flow..
The question for a circular road , which is currently one of struggling with small technological improvements to reduce the impact of constructing, is in fact a question with very limited perspective, which only addresses the business as usual option, only somewhat improved ( if we are lucky) . It does not address the transport question nor the activity surrounding question. , how that is organized. Which could lead to a much more effective solution, as to look at what can be done to reduce marginally the huge impact of resources.
To make a first step myself: I could live with a political decision that in the Netherlands the maximum speed overall will become 80 km an hour. Which should be possible, if in the near future, we have only self driving cars? There is no (travel-) time loss at all in that case, since we can work during the driving hours, even if that takes a bit longer… In stead of rushing to the office to start working….
picture: borrowed from: Toyota Rav 4 – After