Tired of petrol prices rising daily at the pump? A Japanese company has invented an electric-powered, and environmentally friendly, car that it says runs solely on water. Genepax unveiled the car in the western city of Osaka, saying that a liter (2.1 pints) of any kind of water -- rain, river or sea -- was all you needed to get the engine going for about an hour at a speed of 80 km (50 miles). The car will continue to run as long as you have a bottle of water to top up from time to time," Genepax CEO Kiyoshi Hirasawa told local broadcaster TV Tokyo. "It does not require you to build up an infrastructure to recharge your batteries, which is usually the case for most electric cars," he added. Once the water is poured into the tank at the back of the car, the a generator breaks it down and uses it to create electrical power, TV Tokyo said. Whether the car makes it into showrooms remains to be seen. Genepax said it had just applied for a patent and is hoping to collaborate with Japanese auto manufacturers in the future. Most big automakers, meanwhile, are working on fuel-cell cars that run on hydrogen and emit -- not consume -- water.