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Today in Paris, CO2GeoNet, the European Network of Excellence on geological storage of carbon dioxide, is organising an international training and dialogue workshop aimed at providing information and generating discussion about the technical aspects of geological CO2 storage.

Capturing CO2 at large industrial units, particularly fossil fuel based power plants, and storing it underground is one of the strategies being used in the race to significantly reduce atmospheric emissions of greenhouse gases and thus help mitigate climate change and ocean acidification. The technology has now reached a transition stage between research and worldwide deployment. By storing CO2 underground, the carbon released from burning coal, oil and gas is returned to where it was extracted from, rather than releasing it into the atmosphere.

Dr. Nick Riley MBE, Head of Science for Energy at the British Geological Survey and co-ordinator of CO2GeoNet said:
"The vision is to store CO2, captured from large single point emission sources such as coal-fired power plants, within old oil and gas fields or other geological formations beneath the seabed. In January 2007, the European Commission stated that by 2020 all new coal-fired plants should include CO2 capture and storage (CCS) technology and existing plants should also follow.

"In the Energy White Paper 2007, the UK Government announced its intention to hold a competition to develop the UK's first commercial-scale demonstration of CCS. A fundamental step for CO2GeoNet is to ensure that key stakeholders understand what is involved. This workshop will provide a very useful opportunity to gain greater understanding and for any questions to be answered."

Capturing Wind Power
Meanwhile, across the pond in Iowa, a company is tackling the issue of intermitent flows of wind at the wind farm.  The big issue with wind is that it doesn't always blow when people need it most, or it blows too much when they don't need it.  So at the Iowa Stored Energy Park (ISEP) they have decided to store the wind for when they do need it, using a method called Compressed Air Energy Storage (CAES).

There are many ways to effectively store natural energy, batteries being the most obvious (just last month E.ON started a battery project with the storage capacity of 10million AA batteries). At the Stored Energy Park they are using the wind energy to store compressed air in deep underground chambers.  The air is compressed using low-cost, off-peak electricity, and wind that is not being sold on the grid at that time.

When demand outstrips what the wind turbines can produce, the compressed air can then be released, heated and used to drive generating turbines with natural gas.  Whilst it is not as pure green as wind alone, using this techniques means that the gas turbine is up to 40% more efficient than a standard gas turbine. This is because, unlike conventional gas turbines, that consume about 2/3 of their input fuel to compress air at the time of generation, this system pre-compresses air using the off-peak electricity and uses that energy later along with some gas fuel to generate electricity as needed.

Michael McGill of Electricity and Air Storage Enterprises, LLC, a consultant for the ISEP project, said:
"It's a good location. The reservoir is deep enough and wide enough, with good geology. ISEP offers the best means to assure full utilisation of wind energy, whether that power is created by ISEP or purchased."

McGill estimated that CAES plus wind energy from ISEP could account for 20 percent of the energy used in a year at a typical Iowa municipal utility, and could save the cities and their utilities as much as $5 million per year in purchased energy.