The Government are committed to meeting the costs of decommissioning the existing civil nuclear legacy sites by the Nuclear Decommissioning Authority (NDA). This is funded through a mixture of grant in aid and the NDA's commercial income. Over time the contribution from commercial income will decline as the NDA's operational units enter their decommissioning phase. The discounted lifetime cost of delivering the NDA's decommissioning and clean up programme, which is expected to take over 100 years to complete, is estimated at £40.7 billion. With regard to the costs of future nuclear power stations, it will be for energy companies to fund, develop and build new nuclear power stations in the UK, including meeting the full costs of decommissioning.