Battery as Service - to Quote the article - With the launch of the Windsor EV, MG has also introduced a Battery-as-a-Service (BaaS) ownership rental program. Through this, this electric crossover will become more accessible and customers will only pay for its usage as the upfront cost eliminates here. The Windsor EV will be available at Rs 3.5 per km (approx. 4 cents per km), which is 40 percent of the fuel costs of an ICE.