Sustainable development and green national accounts
Defining sustainable development as non-declining utility, the relationship between sustainable development and optimal growth is examined critically in Part 1. The operation of the Hartwick rule for an exhaustible resource is explored under different values of the elasticity of substitution between capital and resources. The Hartwick rule is then extended to the case of fossil fuels, where carbon dioxide emissions arise as an externality. Optimal growth paths with exhaustible resources are shown to be non-sustainable for positive pure rates of time preference or if produced capital depreciates. For linked environment-economy models where pollution stocks dissipate, the optimal steady state is characterized and feasibility conditions for the steady state derived. When resources are renewable and production leads to emissions that damage the resource, the restrictions on the feasible resource stock size in the steady state are determined. Part 2 considers the problem of measuring sustainable development, deriving 'green NNP' as a transformation of the Hamiltonian function for an optimal control problem. Two problems in accounting for exhaustible resources are developed: resource discoveries and heterogeneous resource deposits. The key issue of the treatment of pollution and pollution abatement in green national accounts is explored through a series of six models: flow pollutants, stock pollutants, impairment of pollution dissipation, fossil fuels and carbon dioxide, living resources and acid rain, and household defensive expenditures. The models of flow accounts are extended to green wealth accounting, where it is shown that stocks of pollution can be treated as liabilities in the national balance sheet. Empirical measures of sustainable development are presented in Part 3, with a discussion of the policy implications of green national accounting. Estimates of the value of pollution and 'genuine' savings rates are presented for the UK and selected European countries. The genuine savings analysis is extended to resource depletion and carbon emission damages for over 50 developing countries, revealing significant dissaving in Subsaharan Africa.