Scientists at the Gujarat Energy Research and Management Institute (GERMI) have proposed to use major roads in the country as solar power generators. A paper published by Tirumalachetty Harinarayana, director of GERMI and Pragya Sharma, a co-worker, in the International Journal of Energy, Environment and Engineering, outlines the concept of generating solar power by laying a roof of photovoltaic panels over the roads. While the cost of photovoltaic cells has been decreasing over a period of time, the land needed to lay out the array of cells has been becoming increasingly scarce and expensive. The only investment required is the one-time cost in constructing a simple elevated structure covering the roads. The paper is based on case studies done using computer simulation carried out by the duo on two highways passing through Gujarat. The studies concluded that a PV roof cover over the four-lane 205km-long Ahmedabad-Rajkot highway could generate 104MW of power while the Ahmedabad-Vadodara national highway, 93km long, could generate 61MW. The researchers have also outlined other side benefits of the project such as the shade provided by the over-head solar panels would result in improved vehicle efficiency and longer tyre life, besides reduction in road maintenance costs and rainwater harvesting at selected locations.