Outside home, Holland is doing its bit to meet the increasing demand for fuel by promoting algae farming, says a report. Algae, which can grow in fresh, polluted, sea or farm waste-water, can be used to purify the city’s sewage while feeding on the nitrogen and phosphates in night soil. Algae produce oxygen while using carbon dioxide – the most common greenhouse gas discharged by vehicles, power plants and heavy industries. Such algae farming can go a long way in producing biofuel and energy which could answer the alarming issue of global warming.