The dairy farming sector of European Agriculture is currently under
considerable economic pressure so the aim of each farmer should be
to produce saleable milk, at the lowest cost. One important area
of concern is the expenditure on hot water for hygiene, as to be
acceptable to the buyer the milk must have a low level of
contaminants. Clean milk is produced from clean, healthy udders by
means of equipment which is adequately and appropriately cleaned.
To facilitate this hygienic milk production most dairies are
eguipped with heaters to provide water at 40°C (for cleaning
udders) and 80- 100°C (for plant cleaning). The practice of udder
washing is a subjective process as it depends on the operator's
judgement of a 'clean' udder and his view of necessity. In England
and Wales there are two only accepted methods of plant cleaning,
circulation cleaning and Acidified Boiling Water (A. B. W.). Prior
to the. audit described it was expected that water and electricity
consumption for plant cleaning would be predictable.
To date there has been little information on the volume and
temperature of water used on commercial dairy farms and the
electricty consumed to produce this hot water. It is therefore
difficult for farmers to make informed judgement on methods of
reducing their electricity costs.
Thirteen farms in South Devon have been monitored, to establish
current practice: farmers were questioned about their water use;
electricity and water consumption were metered for two years; and
cleaning practices were observed. This survey has revealed that
many non-standard cleaning methods are used on dairy farms, making
the prediction of water and electricity consumption difficult. The
management of equipment has been revealed as the most important
aspect in determining the energy used.
A computer model has been produced to simulate water heating in the
farm dairy, which can be used to advise farmers as to the energy
cost of their cleaning practices. This model has .been successfully
used on several of the farms surveyed, on one farm its use resulted
in energy savings in excess of 400 kWh per month.The Electricity Counci
