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image PLATFORM/OIL RIG DUNLIN IN THE NORTH SEA SHOWING OIL POLLUTION. image ON A LINFEN STREET, TWO MEN LOAD UP A CART WITH COAL THAT WILL BE USED FOR COOKING. LINFEN, A CITY OF ABOUT 4.3 MILLION, IS ONE OF THE MOST POLLUTED CITIES IN THE WORLD. CHINA’S INCREASINGLY POLLUTED ENVIRONMENT IS LARGELY A RESULT OF THE COUNTRY’S RAPID DEVELOPMENT AND CONSEQUENTLY A LARGE INCREASE IN PRIMARY ENERGY CONSUMPTION, WHICH IS ALMOST ENTIRELY PRODUCED BY BURNING COAL.
A large share of the world’s remaining oil resources is classified as ‘non-conventional’. Potential fuel sources such as oil sands, extra heavy oil and oil shale are generally more costly to exploit and their recovery involves enormous environmental damage. The reserves of oil sands and extra heavy oil in existence worldwide are estimated to amount to around 6 trillion barrels, of which between 1 and 2 trillion barrels are believed to be recoverable if the oil price is high enough and the environmental standards low enough.
Natural gas production, especially in the United States, has recently involved a growing contribution from non-conventional gas supplies such as shale gas. Conventional natural gas deposits have a well-defined geographical area, the reservoirs are porous and permeable, the gas is produced easily through a wellbore and does not generally require artificial stimulation.
One of the worst examples of environmental degradation resulting from the exploitation of unconventional oil reserves is the oil sands that lie beneath the Canadian province of Alberta and form the world’s second-largest proven oil reserves after Saudi Arabia.
Natural gas has been the fastest growing fossil energy source over the last two decades, boosted by its increasing share in the electricity generation mix. Gas is generally regarded as an abundant resource and there is lower public concern about depletion than for oil, even though few in-depth studies address the subject. Gas resources are more concentrated and a few massive fields make up most of the reserves. The largest gas field in the world holds 15% of the Ultimate Recoverable Resources (URR), compared to 6% for oil. Unfortunately, information about gas resources suffers from the same bad practices as oil data because gas mostly comes from the same geological formations, and the same stakeholders are involved. Most reserves are initially understated and then gradually revised upwards, giving an optimistic impression of growth. By contrast, Russia’s reserves, the largest in the world, are considered to have been overestimated by about 30%. Owing to geological similarities, gas follows the same depletion dynamic as oil, and thus the same discovery and production cycles. In fact, existing data for gas is of worse quality than for oil, with ambiguities arising over the amount produced, partly because flared and vented gas is not always accounted for. As opposed to published reserves, the technical ones have been almost constant since 1980 because discoveries have roughly matched production.
Greenpeace is opposed to the exploitation of unconventional gas reserves and these resources are not needed to guarantee the needed gas supply under the Energy [R]evolution scenario. 8.3coal Coal was the world’s largest source of primary energy until it was overtaken by oil in the 1960s. Today, coal supplies almost one quarter of the world’s energy. Despite being the most abundant of fossil fuels, coal’s development is currently threatened by environmental concerns; hence its future will unfold in the context of both energy security and global warming. Coal is abundant and more equally distributed throughout the world than oil and gas. Global recoverable reserves are the largest of all fossil fuels, and most countries have at least some. Moreover, existing and prospective big energy consumers like the US, China and India are self-sufficient in coal and will be for the foreseeable future. Coal has been exploited on a large scale for two centuries, so both the product and the available resources are well known; no substantial new deposits are expected to be discovered. Extrapolating the demand forecast forward, the world will consume 20% of its current reserves by 2030 and 40% by 2050. Hence, if current trends are maintained, coal would still last several hundred years.
references 45 THE INDEPENDENT, 10 DECEMBER 2007. 46 INTERSTATE NATURAL GAS ASSOCIATION OF AMERICA (INGAA), “AVAILABILITY, ECONOMICS AND PRODUCTION POTENTIAL OF NORTH AMERICAN UNCONVENTIONAL NATURAL GAS SUPPLIES”, NOVEMBER 2008.
Research and investment in non-conventional gas resources has increased significantly in recent years due to the rising price of conventional natural gas. In some areas the technologies for economic production have already been developed, in others it is still at the research stage. Extracting shale gas, however, usually goes hand in hand with environmentally hazardous processes. Even so, it is expected to increase.
The ‘tar sands’ are a heavy mixture of bitumen, water, sand and clay found beneath more than 54,000 square miles45 of prime forest in northern Alberta, an area the size of England and Wales. Producing crude oil from this resource generates up to four times more carbon dioxide, the principal global warming gas, than conventional drilling. The booming oil sands industry will produce 100 million tonnes of CO2 a year (equivalent to a fifth of the UK’s entire annual emissions) by 2012, ensuring that Canada will miss its emission targets under the Kyoto treaty. The oil rush is also scarring a wilderness landscape: millions of tonnes of plant life and top soil are scooped away in vast opencast mines and millions of litres of water diverted from rivers. Up to five barrels of water are needed to produce a single barrel of crude and the process requires huge amounts of natural gas. It takes two tonnes of the raw sands to produce a single barrel of oil.
Natural gas obtained from unconventional reserves (known as “shale gas” or “tight gas”) requires the reservoir rock to be fractured using a process known as hydraulic fracturing or “fracking”. Fracking is associated with a range of environmental impacts some of which are not fully documented or understood. In addition, it appears that the greenhouse gas “footprint” of shale gas production may be significantly greater than for conventional gas and is claimed to be even worse than for coal.
A Sustainable EU 27 Energy Outlook