SolaRoad

File:Solaroad7.JPG

SolaRoad

The SolaRoad is the world's first bike path made from solar panels, and is a prototype project testing the feasibility of various proposal 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.

Consortium

The technology was developed by a consortium consisting of Netherlands Organisation for Applied Scientific Research (TNO), Imtech and Ooms Civiel, with a grant of € 1.5 million from the province (county) North Holland as owner of the path. The total cost of the pilot project were € 3.5 million. In addition to the € 1.5 million from the province North Holland were that contributions from TNO, Ooms Civil, Imtech and the European PV-Sin project (partly subsidized by the Dutch government).

Technology

The road surface consists of prefabricated panels with a surface of 1 centimetre (0.39 in) thick hardened glass. Beneath the glass solar cells are installed. TNO states that this energy can be used for lighting of the road, traffic lights and road signs. The energy is also delivered to local dwellings. TNO thinks in future electrical vehicles might be driven by the road itself. This prototype will be studied over the next three years.

In the first month, the path delivered enough energy to sustain one family.

Problems and critics

On 26 December 2014, a 1-square-metre (11 sq ft) 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:

• 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.
• 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.
• 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 Roadways could put environmental progress in the slow lane, because of the high costs of this invention.

Results of trial

After a 6-month test engineers report results are "better than expected". "If we translate this to an annual yield, we expect more than the 70kwh per square metre per year," Sten de Wit, spokesman for SolaRoad, the company that put it in.

The EEVblog compared the 6 and 12 months trial results from SolaRoad with data from 3 rooftop solar systems within a few kilometers of the prototype road. The data showed that rooftop solar systems produced twice the output of the SolaRoad per square meter over the same period.

In November 2015 it was announced that the path has produced 9800 kWh of electricity in one year.

Comparable initiatives

• Solar Roadways
• Wattway
• Smart highway

An innovative cycle lane in South Korea has a solar powered roof, providing shelter from sun and rain for cyclists while generating electricity. In this concept the solar panels are directed in the most profitable position for optimal efficiency.

The 32 km (20 mile) path between Daejeon and Sejong runs down the middle of a six-lane motorway.