The Solar Road is the world's first bike path made from solar panels, and is a prototype project testing the feasibility of various proposals for smart highways. The 72-metre (236 ft) path opened in the week of 21 October 2014, and was designed by a consortium of organizations, which built the pathway in Krommenie, Netherlands.
The path was formally opened in November 2014 by the Dutch Minister of Energy Henk Kamp. On 26 December 2014, a 1-square-metre section of the top-layer coating detached from the glass layer, and that portion of the bike path had to be repaired. In October 2015 the top-layer coating was in such poor condition that it was replaced. Critics of the technology see several problems: First, the panels might get dirty, because they are lying flat. Mud, snow, etc. might accumulate on the surface. The panels cannot be tilted for highest efficiency, which can be done in a roof installation. Cyclists will block the sunlight when passing.
Second, the costs are considered high (3–4 times solar panels on a roof and a conventional pavement layer; about $1000–1400 per 1-square-metre (11 sq ft))($90–125 sq ft). This will result in a payback time of over 50 years. With a price of $1,200 per sqm, a yield of 70 kWh per sqm / year and a lifetime of 20 years a kWh price of $0.86 can be calculated. Compared to an offshore windfarm the cost are 4x higher (average kWh price $0.19). As comparison conventional electricity costs are around $0.05 per kWh. High costs for grid connection, which has to be (over) dimensioned for peak loads only in the summer. Total environmental impact during the lifetime (LCA) is expected to be negative, because of the negative contribution of the reinforced concrete slabs and the epoxy top coating layer in combination with the relatively small amount of produced electricity. Solar Roadcould put environmental progress in the slow lane, because of the high costs of this invention.