Having identified their total annual CO2 emissions, participating organisations will have to purchase carbon allowances at a fixed price of £12 per tonne during the first two years. The initial two-year introductory phase of the CRC will run from the beginning of April 2010 to the end of March 2013. However, allowances will not be sold until the end of the second year. If a participant does not purchase enough allowances during April, it can purchase additional allowances through the secondary market and safety valve, which will have a minimum price of £14 per tonne.