one of the key methods making their extraction economically viable. The multi-stage fracturing technique has facilitated the development of shale gas and light tight oil production in the United States and is believed to do so in the other countries with unconventional hydrocarbon resources. A large majority of studies indicate that hydraulic fracturing in the United States has had a strong positive economic benefit so far. The Brookings Institution estimates that the benefits of Shale Gas alone has led to a net economic benefit of $48 billion per year. Most of this benefit is within the consumer and industrial sectors due to the significantly reduced prices for natural gas. Other studies have suggested that the economic benefits are outweighed by the externalities and that the levelized cost of electricity (LCOE) from less carbon and water intensive sources is lower. The primary benefit of hydraulic fracturing is to offset imports of natural gas and oil, where the cost paid to producers otherwise exits the domestic economy. However, shale oil and gas is highly subsidised in the US, and has not yet covered production costs – meaning that the cost of hydraulic fracturing is paid for in income taxes, and in many cases is up to double the cost paid at the pump. Research suggests that hydraulic fracturing wells have an adverse effect on agricultural productivity in the vicinity of the wells. One paper found "that productivity of an irrigated crop decreases by 5.7% when a well is drilled during the agriculturally active months within 11–20 km radius of a producing township. This effect becomes smaller and weaker as the distance between township and wells increases." The findings imply that the introduction of hydraulic fracturing wells to Alberta cost the province $14.8 million in 2014 due to the decline in the crop productivity, The Energy Information Administration of the US Department of Energy estimates that 45% of US gas supply will come from shale gas by 2035 (with the vast majority of this replacing conventional gas, which has a lower greenhouse-gas footprint). Public debate Politics and public policy Popular movement and civil society organizations An anti-fracking movement has emerged both internationally with involvement of international environmental organizations and nations such as France and locally in affected areas such as Balcombe in Sussex where the Balcombe drilling protest was in progress during mid-2013. The considerable opposition against hydraulic fracturing activities in local townships