Resource use
Fuel use
Our fossil fuel-fired power stations all need a regular and reliable source of fuel. Numerous and complex factors determine our sourcing of fuel and can include various legal restrictions (such as the amount of sulphur in coal), as well as the more obvious economic drivers. The proportion of fuels used from one year to the next will vary to reflect these factors.
Fuel use by generation, Mtce*
| 2001 | 2002 | 2003 | 2004 | 2005 | |
| Coal | 5.94 | 6.81 | 9.97 | 8.49 | 8.52 |
| Oil | 0.07 | 0.06 | 0.03 | 0.23 | 0.51 |
| Gas | 6.47 | 5.86 | 5.78 | 5.48 | 5.55 |
During 2005, there was an overall increase in generation, in part due to the acquisition of Enfield Power Station during the year. High wholesale gas prices over the course of 2005 made gas-fired generation less economically competitive. As a result our coal-fired generation increased over this period. The increase in oil used is largely due to the increased use of our Grain power station to meet peak demand and ensure security of supply.
Fuel use by generation/useful product supplied, Mtce/TWh*
| 2001 | 2002 | 2003 | 2004 | 2005 |
| 0.32 | 0.30 | 0.34 | 0.33 | 0.33 |
Electricity generation efficiency, in terms of fuel used per unit of useful product supplied, has changed little over the past six years, remaining at around 0.33 million tonnes of coal equivalent per terawatt hour (Mtce/TWh).
Transport fuel use
We also use fuel for our commercial vehicles and business travel. The Central Networks and Energy Services commercial fleet vehicles use a significant amount of fuel to carry out their operational activities.
Central Networks commercial diesel use, litres
| 2002 | 2003 | 2004 | 2005 |
| 598,379 | 549,490 | 4,213,301 | 3,146,976 |
The apparent reduction in fuel consumption in 2005 is a result of a number of factors including the rationalisation of reporting systems and the removal of some company cars and pool vehicles from the monitoring systems. The increase in commercial diesel fuel use since 2003 is due to the inclusion of Central Networks West (acquired in 2004). This region has much higher numbers of internal staff carrying out field operations and distances between sites of work tend to be greater because of the rural nature of the area. Furthermore, the data also include the metering business that was acquired at the same time, which has a large number of field staff.
Information on the steps we are taking to reduce our business mileage is available here.
Water use
Our power stations generally use water as a coolant, which requires abstraction of large amounts of water. Power stations are therefore usually located by a river or on the coast. The water used in the cooling process is then returned to its original source. A proportion is lost to the atmosphere as water vapour from power stations with cooling towers. Whilst a degree of modification often occurs, the overall quality of the process water we return to source is close to that abstracted. In previous years we have reported water used by our thermal power stations and other uses as a whole. Changes in operation, however, mean that we no longer feel that this number accurately reflects our pattern of water use.
By far the greatest user of water within E.ON UK is Rheidol hydro-electric power station. Of the water used at Rheidol, almost all is unmodified and returned after use.
Unmodified water use - Rheidol, million cubic metres
| 2001 | 2002 | 2003 | 2004 | 2005 |
| 171 | 170 | 132 | 187 | 165 |
The volume of process and cooling water used by our thermal power stations depends on their pattern of usage. The volume of water we abstract directly from rivers and sources other than the mains supply is not directly measured. Previously it was calculated from plant running time and water pump capacities. Our plants tend now to be used to meet peak demands rather than operating at baseload. This means that it is increasingly difficult to accurately measure water usage in this way. Much of the water used in our plants is reused a number of times before finally being discharged. Water efficiency audits are planned to run over the next couple of years as part of the Integrated Pollution Prevention and Control (IPPC) improvement programme.
Like any other business with office-based operations, our staff and buildings also use a significant amount of potable water. In 2005 our offices, including the Power Technology Centre, used some 111,000 cubic metres of water, as calculated from our utility bills. Our Facilities department monitors water usage statistics through a buildings management programme and is assessing ways in which water consumption might be reduced.
Full details of the environmental performance of each of our sites is available here and detailed environmental trend data going back to 1990 is available here.
