Reducing Greenhouse Gas Production in NSW
Together, coal burning and transport generate most of the State’s greenhouse gasses.
World-wide, oil produces more greenhouse gasses than coal but in NSW coal is our major energy source supplying about twice-as-much energy as oil and gas combined. The production of carbon dioxide from coal burning therefore outweighs the production of oil sourced greenhouse gasses. 47% of this total energy is consumed by industry, most in primary metals and materials production.
In New South Wales, coal-burning power stations are the biggest consumer of coal - the next biggest consumer being the steel industry. Much of the industrial power generated in New South Wales is used by the aluminium industry.
Whereas most industrial and domestic energy is produced by coal (predominantly in the Central Coast, Hunter and Central Western regions), oil (petroleum) is the principal energy source for the transport sector. Cars consume 50% of petroleum fuels, trucks and vans 27%, aircraft and ships 17% and public transport and other minor users 6%.
37% of New South Wales’s energy is consumed by the transport sector which also produces 26% of the carbon dioxide[7], and in addition, produces most of the carbon monoxide and nitrogen oxides[8].
Under present technology, coal produces more carbon dioxide per unit of electric power output than other fossil fuels (and of course very much more than non-fossil sources). The reason that petroleum based fuels produce less carbon dioxide than coal for a given energy output is twofold. Coal is not pure carbon and some of its other constituents reduce combustion efficiency (and produce ash – approximately 25% by weight depending on coal type). Petroleum contains about 27% hydrogen that efficiently burns to water.
Although at first impression it would seem that transport is relatively blameless in the greenhouse picture (as opposed to electricity generation or industrial burning of coal) when conversion efficiencies are taken into account this is not the case.
Present vehicles consume more than four times the energy that is actually delivered as mechanical energy to the wheels. Many commentators believe that vehicle efficiency gains of up to 50% are feasible (but at a cost that is currently prohibitive using existing technology). The inefficiency of internal combustion engines also contributes to excessive weight and materials consumption. Savings in these areas would lead to a significant reduction in the industrial energy consumption involved in manufacturing and processing the materials and in manufacturing the vehicles themselves.
In addition, a great deal of energy is currently wasted because of less than ideal traffic design and the inadequacies of the present road system. These produce variations in traffic speed, requiring frequent braking and acceleration, and impose other inefficiencies, such as steep gradients and poorly designed corners. These factors are very evident in comparisons of town and country fuel consumption rates[9]. The large number of ageing and poorly tuned vehicles on our roads also contributes to this waste and accompanying pollution.
The impact of burning fossil fuels for energy goes beyond small contributions to the global greenhouse effect and include; ozone layer depletion, the production of SO2 and NOx pollutants leading to acid rain, the warming of streams and lakes, and radioactive emissions from flue gas and ash. Emissions from coke ovens exacerbate the local environmental impacts of steelworks.
New South Wales has a multi-billion dollar investment in large-scale conventional coal burning power stations and metallurgical plants. Coal exported to overseas power stations and steel works is a major employer and the nation's principal export. In the coming decade these will increasingly come under pressure as a major contributor to greenhouse gas and other pollutants.