ELEMENTS WHICH REDUCE VALUE Bt
While not endeavoring to set up a rule for the determination
of the extent to which it may be proper to take future requirements
 into account in planning any installation, attention is
called to the fact that any such provision for anticipated future
service adds to the investment of capital and thereby makes
higher earnings necessary than would be required, if, at all
times, the plant capacity could be kept exactly at the momentary
 requirement. Here then is an additional call upon the
rate-payers, which, naturally, will fall heaviest upon those of
the early years, at which time the disparity between actual
demand and the provided capacity is generally greatest. There
lies herein a further reason why the rate-payer in the early years
of the life of any public utility should be relieved, as elsewhere
suggested, of the requirement to meet amortization of capital.
These rate-payers will ordinarily have done their full share if
they contribute operating expenses, interest on the investment,
and whatever may be necessary to anticipate and to meet replacements
 of discarded parts as such replacements become
necessary.
Property not in Use. — Guided by the decisions of the courts
and by the rulings of public service boards and commissions,
it has become customary to discriminate with care between the
property of a public utility which is in use and the property
which may not strictly be regarded as in use. Property which
is in no way related to the service rendered and which is of no
prospective necessity will be left out of consideration in this
discussion. But there is another type of property owned, but
not in use, as for example a reservoir site, acquired by a water
works owner at a favorable moment but not likely to be made
a part of the system for an indefinite period, or a terminal right
of way for a railroad, or an undeveloped water-power which
according to sound judgment must be regarded as necessary for
future expansion though not in active use as a part of the
present system. The wisdom of early acquisition of such properties
 at opportune moments can hardly be questioned. How
to deal with them in making an appraisal for rate-fixing purposes

8.