|Fig. 1: Prototype of solar panel driveway, similar to Solar Roadways technology. (Source: Wikimedia Commons)|
The formation of roadways throughout history has been a testament to people's culture, way of living, and interconnectedness with greater civilization's at large. Whether trading route or expressway, roadways have formed the basis of human existence and survival. Despite this prominence of roadways in society's everyday ability to function, there has been little innovation or evolution to creating better - more technologically-advanced, environmentally friendly, adaptable - surfaces. While the vehicles that travel them have gone from human-powered carts to horse-drawn carriages to "horsepower" driven cars, roadways have seen only basic improvements from tracks to smoothly paved roads. A new innovation lies in the works that could revolutionize roadways, from driveways (prototype pictured right) to expressways. 
The Forever Open Road project aims to address the lack of innovation in roadway technology, attacking the problems with a complex and multi-faceted approach. The Forever Open Road would solve issues on a comprehensive scale with three main goals: to create a road that is adaptable, automated, climate change resilient. 
The adaptable road is a much needed overhaul over the current asphalt and cement highways we're accustomed to driving on. The new pavement structure would provide the ability to upgrade and change infrastructural services and provide an adaptable future for guidance systems and electrically powered vehicles. The adaptability is perhaps the most important aspect of the three goals, as it gives support to the automation and resiliency of the Forever Open Road project. 
The automated road uses an integrated approach between the on-board programs within the vehicles and the technologically advanced roadway systems. The use of "sensory and communications technology" allow the "deployment of advanced (e.g. dynamic) guidance and management systems...in effect improving reliability and efficiency of the network management." Many features tailor to a future of self-driving cars, allowing for "comprehensive, interoperable" connectedness between the vehicles and to the integrated road computing system. 
The climate change resilient road helps solve extreme weather related issue, including temperature fluctuations and precipitation, as well as helping to lessen the consequences of construction relating to pollution (both air and noise). With the energy collected and embedded in the road's structure, it would allow for the roads to be either heated or cooled depending on the climate needs. Further, this technology would be able to heat roadways more susceptible to freezing (such as bridges, colder climate areas) as well as prevent issues in areas with hotter climates (such as rutting, heat islands). 
Solar Roadways: The Solar Roadways Project was created in Idaho, USA, and begun with the inventors attempting to take on the problem of global warming and fossil fuel dependency, both within the United States and eventually abroad. Solar Roadways' ultimate goal is to help the United States lessen its use of internal combustion engines, which would further help the country lessen its foreign oil dependency.  With this data in mind, the idea of a roadway made entirely of connected solar panels - much like those we see on rooftops or in solar fields - was born. The Solar Roadway contributes well to the main goals, giving the Forever Open Road engineers the ability to make the roads adaptable and resilient to climate change (with the eventual goal to allow for induction charging of electrical vehicles as they use the roadway, i.e. Automated Road). It has currently been prototyped for driveways (see Fig. 1) as well as longer, more public stretches of road. 
|Fig. 2: OLEV bus developed by KAIST. (Source: Wikimedia Commons)|
Rollpave: Dubbed the "road on a roll", Rollpave was invented by a Dutch innovation program, "Road to the Future", and is a "prefabricated asphalt mat" that is nearly 30 mm thick, and applied directly to already existing pavement with enough structural strength to support the road's needs. It provides advantages over normal asphalt in that it repairs can be completed up to 50% quicker, and also is claimed to drastically reduce noise pollution by about 6 dBA from normal asphalt. 
Inductive Charging: The Korean Advanced Institute for Science and Technology (KAIST) developed an on-line electric vehicle program that allows electric vehicles to draw power from cables lying below the road surface through a "non-contact magnetic charging method." As seen with KAIST's electric buses (Fig. 2), it could provide a new means for public transportation as well as for the common consumer. This would help to solve the current problem with electric vehicles, in that the cars don't have the range nor do many people feel that they have enough access to charging facilities to make electric vehicles a practical purchase. 
The Forever Open Road project, as well as the many relevant innovations and programs that are involved with it, still need quite a bit of development before they can be considered a viable solution. Another obstacle that the project may face would be the high costs to engineer, install, and maintain the roadways. In 2001, it was estimated that there is 43,478.96 square miles (±4,913.15 square miles) of paved roadway.  The cost of paving with asphalt can be anywhere between $3 and $16 dollars per square foot, giving the overall cost to pave all of this with asphalt as a range between $3.23 × 1012 and $2.16 × 1013 with the actual price likely lying closer to the latter value, given that highways claim more of the square footage of the totals. The solar roadways project, while not yet at the development stage to have a cost feasible panel, estimated using a comparably priced solar panel that the cost of the panels would be about $287.50 per 13.4 square feet. This equates to a range between $2.31 × 1013 and $2.89 × 1013.  It is important to note that this figure solely covers the cost of the solar panel, excluding all delivery, installation, and production costs.
With that said, should the project reach the level of development and refinement necessary to bring this product to the nation, it would provide a comprehensive solution for many of the global warming and fossil fuel related issues that the United States currently faces. From driveways to expressways, the Forever Open Road could create a new normal for transportation and fuel usage within the United States.
© Alana Cook. The author warrants that the work is the author's own and that Stanford University provided no input other than typesetting and referencing guidelines. The author grants permission to copy, distribute and display this work in unaltered form, with attribution to the author, for noncommercial purposes only. All other rights, including commercial rights, are reserved to the author.
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