Innowattech Energy Harvesting Systems based in Israel specialises in the development of custom piezoelectric generators for specific purposes such as harvesting mechanical energy imparted to roadways from passing vehicles. Innowattech has also developed an efficient storage system to collect and store the electricity produced by these generators. The accumulated energy can be used to power traffic lights or street lamps and in the future could be routed into the grid.
Innowattech has conducted trials to demonstrate this energy at the Technion Institute of Technology in Haifa where a vehicle travelled over a road under which IPEG (Innowattech Piezoelectric Electric Generators) had been planted 6cm under the road level and at a distance of 30cm apart. The IPEGs are piezoelectric crystals that can harvest mechanical energy created by changes in weight, motion, vibration and temperature, and convert it to electrical current. The energy harvested was stored in the electronic capacitors of the storage system. Innowattech has also implemented several small projects on a highway near Ben Gurion International Airport.
According to Innowattech, IPEGs are easy and inexpensive to install. Embedded between a road's layers, they are mounted with electronic cards to store traffic-generated energy. The system is usually covered with a layer of asphalt, but concrete or composite concrete and asphalt can also be used. Because systems can be installed when new roads are laid or when regular maintenance work is performed on existing surfaces, installation costs are substantially less than those incurred with either wind or solar systems.
Professor Haim Abramovich, CEO of Innowattech and an associate professor of aerospace engineering at the Technion Institute of Technology heads the project. One truck can generate 2,000 volts, but to create useful electricity will require many IPEGs over hundreds of metres and a high volume of traffic. The power harvesting system can also be used on railways or airline runways.
IDTechex observes that the payback claimed is only 6-12 years but this approach is extremely versatile. These piezoelectric assemblies have unique abilities to harvest energy from weight, motion, vibration and temperature changes. Life has been an issue with some piezoelectric harvesting however. The company observes that, "Innowattech's solution is capable of producing significant amounts of electricity, about 400 kWh from a 1 km stretch of generators along the dual carriageway (assuming 600 vehicles go through the road segment in an hour), enough energy to power 600-800 homes. In Israel alone there are sufficient roads to produce 160 MWh of energy using Innowattech's solution (thus, the roads can provide about 2% of the country's electric energy consumption)." However, IDTechEx sees better potential in providing local harvesting for road furniture, roadside advertising, railway station and airport signage, and the like. Here the installation cost is much less and the benefits go beyond cost to involve such things as energy independence for safety information etc. Many companies are now landing orders for this application of harvesting, some using electrodynamic and some using piezoelectric harvesting.
Credit: Innowattech Energy Harvesting Systems
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