This paper investigates the implications of an
intertemporally dependent demand structure in the market
for an exhaustible resource. The demand structure is
derived endogenously in a partial equilibrium model where
price-taking users combine the resource with capital to
produce final output. It is shown that, when demand for the
resource is modelled explicitly as a derived demand, the
common assumption of an intertemporally independent
sequence of instantaneous demand relationships is justified
if there is a perfect rental market for capital equipment
and there are no internal adjustment costs associated with
either adding to the stock of equipment or subtracting from
it. In the more realistic case where changes in capital
stocks incur adjustment costs, the time-profile of demand
is determined by the underlying programme of
(dis)investment. In this case, changes in the resource
price over time induce a lagged demand response.
The paper goes on to study the properties of an
intertemporal competitive equilibrium, with emphasis on the
demand structure with underlying adjustment costs. Agents
are assumed to transact on perfectly functioning forward
markets, so expectations about the resource price are
always fulfilled a post, The principal results to emerge
from the analysis are that the resource utilization rate
declines to zero in the long term as processes that use the
resource in question are replaced by others; however, the
precise time-path of substitution depends sensitively on
the nature of adjustment costs. For example, if adjustment
costs exhibit non-convexities, substitution away from
processes that use the resource occurs in "pulses", in
contrast to the smooth substitution programme under convex
adjustment costs