Last month the town of Uralla, New South Wales, population of 2754, won a tender to be used as a model for Australia’s first Zero Net Energy Town Project. ZNET will work with the town to investigate opportunities to switch to 100% renewable energy. Some 1300 kilometres south-west, the smaller Victorian town of Newstead plans to switch to 100% solar power by 2017, a pledge backed by the Victorian Labor Party. But is 100% renewable an achievable goal for larger populations, or is it a gimmick for tiny towns that has no real-world impact? Professor Anthony Vassallo, director of the Centre for Sustainable Energy Development at the University of Sydney, says the towns’ ambitions are achievable -- with proper planning. “For towns the size of Uralla, you could envisage having enough storage to ride through the night or days of low sun.” “You can buy as much energy storage as you want, but every extra hour of storage costs money,” he said. “You really have to plan it.” But is such an initiative scalable? The City of Sydney also has plans to have the capacity to generate its electricity from renewable sources by 2030, but Vassallo doubts that it will ever disconnect from the grid. “There will always be times where you’re going to have to rely on grid supply … and the grid mix is still predominately fossil fuels.” He says towns made up of residential homes and small businesses could transition more easily than towns with larger industrial loads, which require more electricity. Both Uralla and Newstead are inspired by community-led initiatives around the world, particularly in Europe. Where has this been done before, and what can Uralla and Newstead learn from other efforts? The towns on this list are just some examples of towns and communities that have made the transition to renewable energy. Feldheim, Germany Population: 145 Energy: wind, solar, biogas from wood chips Feldheim began its transition to renewable energy in 1995, becoming independent from the main grid in 2010. Residents of the town contributed the funds to build a wind farm, which now has 47 wind turbines and produces much more electricity than the town needs. Feldheim is able to sell 99% of the energy from the wind farm back to the grid. Feldheim is also home to a solar park, and the power it generates is also sent back to the main grid. The town has also replaced heating oil with biogas, which is generated from wood chips. The biogas also covers electricity supply when the wind turbines are not working. The town is also investing in battery storage systems to help with consistency of supply. Rock Port, Missouri, United States Population: 1266 Energy: wind This small American town has four wind turbines, capable of producing 16 million kWh of energy per year. For them to work, the wind needs to be blowing at about 9 miles per hour, and they achieve their maximum output at 14 miles per hour. For most of the year, the wind speeds in Rock Port are easily sufficient, but in September the monthly average speed dips to 2 miles per hour. Rock Port is still connected to the grid, so residents can access electricity all year round. Still, the town says it can meet 123% of its energy needs from the wind farm and sells the excess back to the grid. Isle of Eigg, Scotland Population: 87 Energy: hydro, wind, solar This Isle of Eigg, off the west coast of Scotland, used to be powered by diesel generators. In 2008, the island was able to generate enough power from renewable sources to cover residents' needs 24/7.  The island has three hydroelectric generators, four wind turbines and a photovoltaic array, in addition to backup generators. Each household is limited to using 5kW at a time, while businesses are allowed to use 10kW. This is enough for 50 100w lightbulbs, or a kettle and a washing machine. Although residents have to be cautious, there are times when the island produces excess electricity. Dharnai Village, Bihar, India Population: 2400 Energy: solar In 2011, according to Indian census data, 83% of households in the state of Bihar could not access electricity. In July this year, Greenpeace teamed up with financial services organisation BASIX and the Indian Centre for Environment and Energy Development to assist Dharnai Village to install a solar micro-grid and deliver power to residents. However, according to some reports, the villagers were not happy with their deal. When former chief minister Nitish Kumar visited the village in August, residents asked him for “real electricity". At present, BASIX says the initiative needs to monitor how much electricity the grid generates before residents will be allowed to use it for “luxury items” like televisions. Greenpeace says the grid produced 2450 kWh of energy this week. A four-person home in Brunswick, Melbourne, uses 19.5kWh per day in winter. If residents of Dharnai Village were to use electricity as Melburnians do, the micro-grid would need to produce a lot more electricity. Juhnde, Lower Saxony, Germany Population: 1000 Energy: biogas The small village of Juhnde was developed as a model “bioenergy village”. The town has a biogas plant, which supplies power generated from methane from cow manure as well as maize, wheat and barley. It produces 500MWh of energy per year, which is twice the amount of power the village needs. This also generates 6500 MWh of heat from a wood chip boiler to help meet the increased demand for energy in winter months. Like Feldheim, Juhnde sells the excess back to the grid. Juhnde is being used as a model for other bioenergy villages throughout Germany. Critics of bioenergy say that it puts a strain on land resources. In Juhnde, 25% of the village’s farmland and 10% of its forests are used to supply the biogas plant.