nor do any revenues, or debts, from the estate accrue to him. Instead, the Crown Estate is owned by the monarch in right of the Crown, a corporation sole representing the legal embodiment of the state. It is held in trust and governed by Act of Parliament, to which it makes an annual report. Revenue from the Crown Estate has been predicted to double in real terms between 2010 and 2020 with additional lease revenues deriving from the development of offshore wind farms within Britain's Renewable Energy Zone, the rights of which were granted to the Crown Estate by the Energy Act 2004. The Duchies of Lancaster and Cornwall are Crown entities holding land and other assets to produce an income for, respectively, the British Sovereign (now King Charles III) and the monarch's eldest son (if he is next in line to the throne). The revenue profits of the Duchy of Lancaster are presented to the Sovereign each year and form part of the Privy Purse, providing income for both the official and private expenses of the monarch. The Duke of Cornwall receives revenue for charitable work and official activities. These financial arrangements also cover the official expenditure of some members of his immediate family. The occupied official royal residences such as Buckingham Palace, Holyrood Palace and Windsor Castle are held in trust by the sovereign, as is the Palace of Westminster. The Royal Household is expected to use the Sovereign Grant to maintain the residences. In May 2009 the Queen requested an extra £4 million annually from the government to carry out a backlog of repairs to Buckingham Palace. In 2010, the Royal Household requested an additional grant from the Department for Culture, Media and Sport but were refused on the basis that the scheme was "aimed at schools, hospitals, councils and housing associations for heating programmes which benefit low-income families". Over a third of the Royal estate was in disrepair by 2012–13 according to a report by the Public Accounts Committee. The cost of restoration was estimated to be £50 million, but the Reserve Fund was at a historic low of £1m. The monarch is also responsible for using the Sovereign Grant to pay the wages of 431 of the approximately 1,200 Royal Household staff, amounting to £18.2 million in 2014–15. In 2013, the Guardian newspaper reported that Buckingham Palace was using zero-hour contracts for its summer staff.