The need for affordable and environmentally friendly sources of electrical energy is becoming increasingly urgent in line with the rising energy consumption and growing awareness of the harmful impacts of fossil fuel use. This research aims to design and build a prototype of an electricity generator utilizing a motorcycle coil as a source of mechanical energy, which is then converted into electrical energy to serve as a backup during household-scale power outages. The method employed is Experimental and Quantitative, producing environmentally friendly energy. The test results using three types of test media and a CT 1A (Step-up) transformer with an 8W LED lamp load showed the highest output of 82V from the initial 12V + 12V input, with a current of 0.10A and power of 8.23W. For a 5W incandescent lamp load, the highest output reached 136.5V, with a current of 0.27A and power of 36.8W. Meanwhile, using a 12W mobile phone charger load, the highest output voltage achieved was 176V, with a current of 0.97A and power of 17W. The energy-saving efficiency of the electricity generator using a motorcycle coil compared to electricity from the state power grid (PLN) amounted to Rp 29,650 per year, or about 28% of the total cost if household lighting relies solely on PLN electricity