The harder Rob Devereux works out on the elliptical skiing machine, the brighter the light above him shines and the more sweat forms on his brow. Beside him on the floor is a transparent plastic box containing a bewildering array of red wires and brown transformers and transistors, and a gauge that monitors how much energy he is using. The energy generated by his workout would normally be transformed into heat, but with inventor Lucien Gambarota's specially built technology, it is turned into electricity. The equipment beside the ski machine instantly converts the energy into power that illuminates the strip lighting above. That machine and 17 others in the gym are also connected to an AC/DC converter, a charger and two large batteries tucked away in a cupboard in an upstairs office. The batteries can store energy to be used to power lights, and possibly air-conditioning and other electrical equipment throughout the gym. Gym members were pedalling hard yesterday to light up three bulbs fitted in the upstairs workout area - the harder they cycled, the brighter the bulbs shone. Downstairs, five elliptical skiing machines have been linked to overhead lights, while eight stepping machines will soon come online to power the lights. Mr Devereux said the equipment had been welcomed by club members who were more than happy to combine their workouts with saving the world.