The programme began when Nissan took on production of the Micra car at its Sunderland works. In order to maintain profitability and keep the price of the Micra as low as possible, it had to operate at no net costs beyond those normally associated with environmental protection.
However, Nissan decided that cash saved by one environmental initiative could be redeployed to pay for others, and it was this innovative feature and the achievements to date which won it the Royal Society of Arts' annual environmental management award in June.
The programme's components are "plant environment", covering workplace improvements such as noise and health and safety; "plant impact", including solvent emissions and effluent treatment; waste management; conservation of energy and other resources; and neighbourhood protection. The amortised annual costs incurred to date are:
The largest cost, that of plant impact, is due largely to Nissan's move to water-based paints. This also includes the cost of an effluent treatment plant and the use of fluidised bed pyrolysis for cleaning contaminated plant items, making caustic cleaning chemicals redundant.
Nissan claims to be the first UK manufacturer to use a novel water-based paint process that reduces paint losses, although Volvo in Sweden was the first world-wide. It is based on applying an electrostatic charge to the paint particles so as to attract them to the car surface and reduce losses to drain. Paint transfer efficiencies are typically of the levels attained with solvent spraying, although the machine efficiency is only 90%, compared with 95% for machines using solvents.
The relatively poor efficiency of the machine, the higher capital expenditure involved, and the increase in energy needed to cure the paint means that the water-based system costs more than conventional processes. But unlike existing methods, it will comply with limits on emissions of volatile organic compounds which come into effect later in the decade under the Environmental Protection Act 1990.
Offsetting these extra costs were savings in recycling fuel tank cut-offs for reuse in new fuel tanks. Besides conserving raw materials, this project also reduced Nissan's landfill disposal costs.
Another significant saving came from improving the distribution system. Traditionally, 22 suppliers in the Midlands shipped their components separately to Nissan. These are now collected from the suppliers and delivered to Sunderland in consolidated loads, saving 3.9 million miles annually - an 80% reduction.
Nissan's energy conservation programme saves £58,000 per year through improved oven insulation, more efficient energy usage in the casting plant, and new automatic lighting controls. A further £65,000 is saved annually by a recovery system for swarf and cutting fluids which produces a scrap product that is cleaner and easier to process into ingots.